JP2011009805A - Optical wireless communication terminal unit, optical wireless communication system, optical wireless communication method, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem that a conventional optical wireless communication terminal unit cannot bidirectionally exchange information between a device for transmitting information by optical wireless communication and a device for receiving information.SOLUTION: The optical wireless communication terminal unit includes a light source position detection section 102 for detecting an optical wireless communication light source within a photographed image that a photographing section 101 has obtained by photographing light sources including the optical wireless communication light source, and acquiring position information on the optical wireless communication light source, an information acquisition section 103 for acquiring information on a position where communication light impinges on, namely information on an incidence position of the light of the optical wireless communication light source from the position information, and acquiring information to be transmitted that is transmitted from the optical wireless communication light source at a position indicated by the information by optical wireless communication, an output section 104 for outputting the information, a section 105 for receiving information transmitted to a terminal for receiving information transmitted to the terminal, namely a transmission destination, and a section 107 for transmitting information transmitted to a terminal for transmitting information transmitted to the terminal from a light source 106 for transmission by optical wireless communication.

Description

  The present invention relates to an optical wireless communication terminal apparatus that receives information transmitted by optical wireless communication using light such as visible light.

  Conventionally, an LED light source for illumination, a power line for supplying power to the LED light source, information modulation means for modulating and multiplexing a plurality of pieces of information on the power line and superimposing them on a power waveform, and on the power line Broadcasting system having filter means for selectively separating one or more from a plurality of modulated information and controlling the light quantity or blinking of the LED light source, and transmitting information by changing or blinking the light quantity of the LED light source (For example, refer to Patent Document 1).

  In this broadcasting system, information transmitted by visible light communication is received using a light receiving terminal.

Japanese Unexamined Patent Publication No. 2004-147063 (first page, FIG. 1 etc.)

  However, in a situation where a light source that performs optical wireless communication such as visible light communication, a light source that does not perform optical wireless communication, and ambient light such as indirect illumination and natural light, etc. are mixed, When the information transmitted from the light source is received by optical wireless communication, the light receiving terminal cannot selectively receive only the light emitted from the light source that performs optical wireless communication. The light emitted by other light sources that are not performed is also received. For this reason, light emitted from a light source that does not perform optical wireless communication is received in a mixed manner with light emitted from a light source that performs optical wireless communication, so that information transmitted by optical wireless communication can be received with high accuracy. There was a problem that it was not possible.

  In addition, since the light receiving terminal can only receive information transmitted by optical wireless communication, information input to the light receiving terminal, information held by the light receiving terminal itself, and the like are transmitted to an apparatus that transmits information by optical wireless communication. There was a problem that it was not possible to communicate. For this reason, information cannot be exchanged bidirectionally between the light receiving terminal and an apparatus that transmits information by optical wireless communication.

  An optical wireless communication terminal device according to the present invention includes an imaging unit that acquires an image by capturing one or more light sources including an optical wireless communication light source that is a light source that performs optical wireless communication, and an image that is an image acquired by the imaging unit. From the position information of the optical wireless communication light source detected by the optical wireless communication light source in the image, and the position information of the optical wireless communication light source acquired by the light source position detection unit. Communication light incident position information, which is information of a position where light output from the optical wireless communication light source is incident, is acquired and transmitted from the optical wireless communication light source by optical wireless communication at the position indicated by the communication light incident position information. An information acquisition unit that acquires light source transmission target information that is information, an output unit that outputs information acquired by the information acquisition unit, and terminal transmission target information reception that receives terminal transmission target information that is information to be transmitted Optical communication terminal apparatus comprising: a transmission light source for transmitting the terminal transmission target information; and a terminal transmission target information transmission unit for transmitting the terminal transmission target information from the transmission light source by optical wireless communication It is.

  With this configuration, information transmitted from a light source that performs optical wireless communication can be accurately received, and bidirectional information can be exchanged with a device that includes a light source that performs optical wireless communication. it can.

  An optical wireless communication system of the present invention is an optical wireless communication system including an optical wireless communication terminal device and an optical wireless communication light source device having one or more optical wireless communication light sources that are light sources for performing optical wireless communication, The optical wireless communication terminal device includes: an imaging unit that acquires an image by capturing one or more light sources including an optical wireless communication light source included in the optical wireless communication light source device; and a captured image that is an image acquired by the imaging unit A light source position detection unit that detects a position of the optical wireless communication light source and obtains position information that is position information of the optical wireless communication light source; and a position information of the optical wireless communication light source acquired by the light source position detection unit; Communication light incident position information that is information on a position where light output from the communication light source is incident is acquired, and optical wireless communication that is a light source of the optical wireless communication light source device at a position indicated by the communication light incident position information An information acquisition unit that acquires light source transmission target information that is information transmitted by optical wireless communication from a source, an output unit that outputs information acquired by the information acquisition unit, and terminal transmission target information that is information to be transmitted Terminal transmission target information receiving unit, a transmission light source for transmitting the terminal transmission target information, and a terminal transmission target information transmission unit for transmitting the terminal transmission target information from the transmission light source by optical wireless communication The optical wireless communication light source device includes: a terminal transmission target information receiving unit that receives terminal transmission target information transmitted by optical wireless communication from the optical wireless communication terminal device; and a terminal transmission received by the terminal transmission target information receiving unit. A reception information transmission unit that transmits target information; and a light source transmission target information reception unit that receives light source transmission target information that is information to be transmitted to the optical wireless communication terminal device; One or more optical wireless communication light sources that are light sources that perform optical wireless communication for transmitting the light source transmission target information, and the light source transmission target information received by the light source transmission target information receiving unit are the optical wireless communication light sources. To an optical wireless communication system including a light source transmission target information transmitting unit that transmits the optical wireless communication.

  With this configuration, the optical wireless communication terminal apparatus can accurately receive information transmitted from the light source that performs optical wireless communication, and between the optical wireless communication terminal apparatus and the optical wireless communication light source apparatus. , It is possible to exchange information in both directions

  In the optical wireless communication system according to the present invention, in the optical wireless communication system, the optical wireless communication light source device further includes an identification information storage unit in which identification information that is information for identifying the device itself can be stored. The information transmitting unit is an optical wireless communication system that transmits terminal transmission target information received by the terminal transmission target information receiving unit in association with identification information of the own device.

  With this configuration, the optical wireless communication light source device that has received the terminal transmission target information transmitted from the optical wireless communication terminal device can be identified using the identification information, and the optical wireless communication terminal device that has transmitted the terminal transmission target information As a result.

  According to the optical wireless communication terminal device and the like according to the present invention, it is possible to accurately receive information transmitted from a light source that performs optical wireless communication, and to both devices with a light source that performs optical wireless communication. Can exchange information on the desired direction.

1 is a conceptual diagram of an optical wireless communication system according to an embodiment of the present invention. Block diagram of the same optical wireless communication terminal device Block diagram of the same optical wireless communication light source device Block diagram of the server 30 Flowchart for explaining the operation of the optical wireless communication terminal device Flowchart for explaining the operation of the optical wireless communication terminal device Flowchart for explaining the operation of the optical wireless communication light source device Flow chart explaining operation of the server Schematic diagram showing the relationship between marker signal and sampling period in the same optical wireless communication system Schematic diagram for explaining a specific example of the optical wireless communication system The figure which shows an example of the program information management table | surface of the server 30 The figure which shows an example of the basic information of the server 30 The figure which shows the picked-up image which the optical wireless communication terminal device image | photographed The figure which binarized and showed the picked-up image which the same optical wireless communication terminal unit photographed The figure which shows an example of the light source coordinate management table | surface of the same optical wireless communication terminal device The figure which shows an example of the visible light communication light source management table | surface of the same optical wireless communication terminal device The figure which shows the permeation | transmission area | region of a liquid crystal panel for demonstrating operation | movement of the optical wireless communication terminal device The figure which shows the state in which the light which permeate | transmitted the liquid crystal panel is received for demonstrating operation | movement of the optical wireless communication terminal device The figure which shows the example of a display of the same optical wireless communication terminal device The figure which shows the example of a display of the same optical wireless communication terminal device Schematic diagram showing an example of the external appearance of the computer system The figure which shows an example of a structure of the computer system

  Hereinafter, embodiments of an optical wireless communication terminal device and the like will be described with reference to the drawings. In addition, since the component which attached | subjected the same code | symbol in embodiment performs the same operation | movement, description may be abbreviate | omitted again.

(Embodiment)
FIG. 1 is a conceptual diagram of an optical wireless communication system according to the present embodiment.

  The optical wireless communication system 1 includes an optical wireless communication terminal device 10, an optical wireless communication light source device 20, and a server 30. The optical wireless communication light source device 20 and the server 30 are connected so as to be communicable via a power communication line, a network, or the like. In this conceptual diagram, the case where the optical wireless communication terminal device 10 is a portable device and the server 30 is a computer is shown as an example. It may be a device. In addition, here, the case where there is one optical wireless communication terminal device 10 and one optical wireless communication light source device 20 has been described as an example, but two or more of each may be provided.

  Optical wireless communication is a device that transmits data by changing the intensity of light emitted from a light source in accordance with a signal obtained by modulating data to be transmitted. In other words, it is a technique for transmitting information by fluctuations in light intensity. The fluctuation of light intensity is a concept including blinking of light. However, the blinking of light here may be considered as a change in light intensity. The light used for optical wireless communication may be visible light or not visible light. Optical wireless communication is a concept including visible light communication in which communication is performed using visible light.

  In the present embodiment, in particular, the optical wireless communication system is a visible light communication system that performs visible light communication, and the optical wireless communication terminal device 10 performs visible light communication, a visible light communication terminal device, and an optical wireless communication light source. A case where the device 20 is a visible light communication light source device that performs visible light communication will be described as an example. However, the present invention can also be applied to devices that perform optical wireless communication other than visible light communication. Here, a light source that performs visible light communication is referred to as a visible light communication light source. In the present embodiment, the visible light communication light source is preferably an LED (Light Emitting Diode) light source. In addition, in order to prevent a false detection in which a light source other than a visible light communication light source is erroneously detected as a visible light communication light source, a light source other than a visible light communication light source is also a light source with little flickering, for example, other than a fluorescent lamp. An LED light source or an incandescent lamp is preferred. Since the visible light communication technique such as a configuration for transmitting information via the visible light communication light source is a known technique, a detailed description thereof will be omitted.

  FIG. 2 is a block diagram for explaining the configuration of the optical wireless communication terminal apparatus 10. The optical wireless communication terminal device 10 includes an imaging unit 101, a light source position detection unit 102, an information acquisition unit 103, an output unit 104, a terminal transmission target information reception unit 105, a transmission light source 106, a terminal transmission target information transmission unit 107, a first A lens 111 and a beam splitter 112 are provided. The optical wireless communication terminal device 10 is a device that can receive information transmitted from the light source of the optical wireless communication light source device 20 and further transmit information to the optical wireless communication light source device 20.

  The imaging unit 101 includes an image sensor 1011 and image processing means 1012.

  The light source position detection unit 102 includes a light source detection unit 1021 and a light source selection unit 1022.

  The information acquisition unit 103 includes incident position information acquisition means 1031, selective transmission means 1032, light receiving means 1033, information acquisition means 1034, and a second lens 113.

  The selective transmission means 1032 includes a liquid crystal panel 10321 and a light shielding control means 10322.

  The terminal transmission target information transmission unit 107 includes a modulation unit 1071 and a transmission unit 1072.

  The first lens 111 is a condensing unit that condenses light emitted from one or more light sources including a light source used for visible light communication and enters the optical wireless communication terminal device 10. In this embodiment, the light source used for visible light communication is specifically the light source included in the optical wireless communication light source device 20. The light condensed by the first lens 111 is incident on the photographing unit 101. Instead of the first lens 111, other condensing means such as a concave mirror may be provided. When the optical wireless communication terminal device 10 is held in a state that can be operated by the user or the like, the first lens 111 has an optical axis in the direction in which the light source is arranged, for example, usually the light source is arranged. It is preferable to install in the optical wireless communication terminal device 10 so as to face the ceiling.

  The beam splitter 112 transmits the light incident through the first lens 111 and causes the light to enter the imaging unit 101, and further reflects the incident light to enter the information acquisition unit 103 described later. Specifically, the beam splitter 112 causes the transmitted light to enter the image sensor 1011. In addition, the beam splitter 112 inputs the reflected light to the selective transmission unit 1032 of the information acquisition unit 103 described later, more specifically, the liquid crystal panel 10321. Here, the half mirror is also considered as one of the beam splitters 112. In the present embodiment, a structure is provided that allows light incident through the first lens 111 to be incident on both the photographing unit 101 and the information acquisition unit 103 simultaneously or by switching. If so, a configuration other than the beam splitter 112 may be provided. For example, light that is incident through the first lens 111 is provided by providing a flip-up type mirror used for a so-called single-lens reflex camera or the like instead of the beam splitter 112 and controlling the timing of raising the mirror. May be switched and made incident on both the imaging unit 101 and the information acquisition unit 103. In addition, the positional relationship among the imaging unit 101, the information acquisition unit 103, and the first lens 111 is relatively moved, and the imaging unit 101 and the information acquisition unit 103 are switched and arranged on the optical axis of the first lens 111. You may be able to do it.

  The imaging unit 101 captures one or more light sources including a visible light communication light source that is a light source that performs visible light communication, and acquires an image. In this embodiment, the visible light communication light source described here is specifically a visible light communication light source included in the optical wireless communication light source device 20. Here, an image captured and acquired by the imaging unit 101 is referred to as a captured image. The imaging unit 101 captures one or more light sources including a visible light communication light source via the first lens 111, and acquires information on an image obtained by capturing the one or more light sources. In addition, light sources other than a visible light communication light source are light sources, such as normal illumination in which information is not transmitted using light. The captured image may be a color image as long as the position of the light source that performs visible light communication can be detected by the light source position detection unit 102 described later, or an image having two or more gradations, for example, a grayscale image. Alternatively, it may be an image representing only the brightness of the image. The photographing unit 101 may photograph a still image or a photographed image that is a moving image composed of a plurality of frames. In this embodiment, the configuration of the imaging unit 101 will be described by taking as an example a case where the imaging unit 101 includes the image sensor 1011 and the image processing unit 1012. The imaging unit 101 can usually be realized by an imaging device, a GPU (Graphics Processing Unit), an MPU, a memory, or the like. The processing procedure of the photographing unit 101 is usually realized by software, and the software is recorded on a recording medium such as a ROM. However, it may be realized by hardware (dedicated circuit).

  The image sensor 1011 outputs an electrical signal corresponding to the incident light. The imaging element 1011 is an element configured by arranging a plurality of light receiving elements (not shown). Specifically, the image sensor 1011 is a so-called image sensor. The image sensor 1011 is, for example, a CCD or a CMOS. The image sensor 1011 converts incident light into an electric signal corresponding to the intensity of the light, and outputs an electric signal whose waveform changes according to a change in the intensity of the incident light. Specifically, each light receiving element constituting the image sensor 1011 outputs an electrical signal corresponding to the intensity of the incident light. As a result, the image sensor 1011 is on the light receiving surface of the image sensor 1011. An electric signal corresponding to the intensity distribution of the incident light is output. In general, the image sensor 1011 can extract only an electric signal obtained by a light receiving element in a desired region according to the received light. In the present embodiment, the light emitted from the subject and the light reflected by the subject are collected by the first lens 111 and the like, and are incident on the image sensor 1011. A color filter such as RGB is usually provided on the incident surface of the image sensor 1011, and the color image is finally selected by selecting the color of light incident on each light receiving element by the color filter. Is configurable. However, the color filter may be omitted as necessary in the structure of the image sensor 1011 and the light source detection. The color filter may be changed to a filter that transmits only light of a specific wavelength.

  The image processing unit 1012 receives an electrical signal output from the image sensor 1011 and configures an image of a subject. Specifically, the subject image is an image obtained by photographing one or more light sources including a visible light communication light source that is a light source that performs visible light communication. Specifically, the image processing unit 1012 demodulates an electrical signal output from the image sensor 1011 and converts it into a digital signal or the like to constitute information of the captured image. The process in which the image processing unit 1012 configures the information of the captured image is a known technique, and thus detailed description thereof is omitted. The image configured by the image processing unit 1012 is, for example, a moving image including one or more still images and a plurality of frames. The file format of the image that the image processing unit 1012 configures is not limited. The image processing unit 1012 temporarily stores information on the configured image in a storage medium such as a memory (not shown). The image processing unit 1012 can be realized by, for example, a DSP (Digital Signal Processor), a GPU, a memory, or the like. The processing procedure of the image processing means 1012 is usually realized by software, and the software is recorded on a recording medium such as a ROM. However, it may be realized by hardware (dedicated circuit).

  The light source position detection unit 102 detects a visible light communication light source in a captured image that is an image acquired by the imaging unit 101. And the positional information which is the information of the position of the detected visible light communication light source is acquired. The position of the visible light communication light source described here is the position of all or some of the pixels in the region where the image of the visible light communication light source exists in the photographed image, or the image of the visible light communication light source in the photographed image. The position of the center point of the area to be processed, the position of the outline of the area, the position representing the area such as each corner, and the like. The position information acquired by the light source position detection unit 102 is, for example, information on coordinates in the captured image indicating the position of the detected visible light communication light source. The unit of the coordinate information is, for example, a pixel unit or a relative value with respect to the vertical or horizontal length of the captured image. Also, information indicating the position of a light receiving element (not shown) in the image sensor 1011 that is an output source of an electrical signal used for obtaining a pixel of a visible light communication light source in a captured image, for example, information on coordinates. Also good.

  For example, the light source position detection unit 102 detects the positions of all the light sources including the visible light communication light source in the captured image. Then, it is determined whether each detected light source is a light source whose light intensity varies. If the light intensity varies, the detected light source is determined as a visible light communication light source, and the detected light source Is obtained as position information of the visible light communication light source. The light source position detection unit 102 may detect the visible light communication light source by a method other than the above. For example, a visible light communication light source emits light of a predetermined color different from other light sources, and a region where pixels close to this color exist in a captured image is searched and searched. The position indicating the area may be detected as the position of the area of the visible light communication light source. The light of a predesignated color is a concept that includes light from which a color of a specific wavelength is excluded. In addition, a marker indicating that the visible light communication light source has been specified in advance, on the surface of the visible light communication light source or in the vicinity thereof, is provided in advance, and the specified shape is obtained by pattern matching or the like. A process of detecting a matching shape may be executed in the captured image, and a matching image or a region where pixels in the vicinity thereof having high luminance exist may be detected as a visible light communication light source. This marker is preferably a marker having a color that is easy to detect, such as a red LED. Alternatively, the shape or arrangement of the visible light communication light source is designated in advance, the shape matching the designated shape or arrangement is detected in the captured image by pattern matching or the like, and the region of the matching shape is You may judge that it is a visible light communication light source. In the case where the visible light communication light source performs visible light communication by turning on and off the light completely, when a moving image is used as a captured image used for detecting the position of the visible light communication light source, the captured image is not necessarily displayed. Since not all frames contain an image of a visible light communication light source, even if the above visible light communication light source is detected for one frame image, the visible light communication light source is not necessarily detected reliably. It is not always possible. Therefore, the visible light communication light source is detected with the color and shape as described above for each of the plurality of frames, and all the information on the position where the visible light communication light source is detected at least once is used as the position information of the visible light communication light source. It is preferable to obtain. That is, it is preferable to obtain the logical sum of the position information of the visible light communication light source acquired from each of the plurality of frame images. Alternatively, the position information of the visible light communication light source may be acquired from an image obtained by combining a plurality of frames of a moving image in advance. When a still image is used as a captured image, it is preferable to use a still image captured with an exposure time sufficiently longer than the on / off cycle of the light source for visible light communication. In addition, it is preferable that the light source position detection unit 102 continuously and repeatedly acquires the position information of the image of the visible light communication light source in the captured image, and constantly updates the position information to the latest information. By doing in this way, even if the position of the optical wireless communication terminal device 10 is changed due to movement or the like, it is possible to always obtain accurate position information of the visible light communication light source. The light source position detection unit 102 can be usually realized by an MPU, a memory, or the like. The processing procedure of the light source position detection unit 102 is usually realized by software, and the software is recorded on a recording medium such as a ROM. However, it may be realized by hardware (dedicated circuit).

  In the present embodiment, in particular, the light source position detection unit 102 includes a light source detection unit 1021 and a light source selection unit 1022, which are used to acquire position information of a visible light communication light source from a captured image. Will be described as an example.

  Here, as an example, information to be transmitted by visible light communication from an external visible light communication light source and a marker signal that is a signal used to detect the position of the visible light communication light source are superimposed. Assume that information is being sent. Information to be transmitted by visible light communication transmitted from an external visible light communication light source is referred to herein as light source transmission target information. The light source transmission target information is, for example, information transmitted by visible light communication from the visible light communication light source 205 of the optical wireless communication light source device 20 described later. The light source transmission target information may be any information, and may be any information such as image data, audio data, text data, and an execution file. The marker signal is a signal having a predetermined frequency and a value whose value fluctuates in a predetermined pattern. The marker frequency is usually binary data in which a predetermined pattern is repeated at a predetermined cycle. Here, the frequency of the marker signal is referred to as a marker frequency. Assume that the marker frequency is a frequency at which the image sensor 1011 can also acquire information. On the other hand, the light source transmission target information transmitted by visible light communication may be information having a frequency higher than the frequency that can be received by the image sensor 1011 as long as the light receiving unit 1033 described below can receive light. In addition, here, as an example, the light output from the visible light communication light source transmits information due to fluctuations in the intensity of light, and is normally turned on when transmitting information. To do.

  The light source detection unit 1021 detects a light source in a captured image that is an image acquired by the imaging unit 101. The light source to be detected here is a light source including a visible light communication light source and a light source other than the visible light communication light source. For example, the light source detection unit 1021 detects a region with high luminance from a captured image captured by the image sensor 1011. When the captured image is a color image, the luminance described here may be a luminance for a specific color or color component, for example, a blue luminance. Further, a color region in a specific range may be detected. The areas detected in this way are areas determined as all light sources including the visible light communication light source in the captured image. For example, the light source detection unit 1021 determines that an area in which a high-luminance pixel in the captured image, for example, a pixel having a luminance value equal to or higher than the threshold exists adjacent to the number of pixels specified in advance is a light source. You may do it. The light source detection unit 1021 may detect the position of the light source by other methods. For example, when the area of a color specified in advance, for example, the color of light emitted from the light source is known in advance, by specifying this color, the area where pixels close to this color in the photographed image exist can be used as the light source. It can be determined that there is. Alternatively, when the shape of the light source can be specified in advance, the light source may be detected from the captured image by pattern matching. The light source detection unit 1021 can be usually realized by an MPU, a memory, or the like. The processing procedure of the light source detection means 1021 is usually realized by software, and the software is recorded on a recording medium such as a ROM. However, it may be realized by hardware (dedicated circuit).

  The light source selection unit 1022 selects a visible light communication light source among the light sources detected by the light source detection unit 1021 in the captured image, and acquires position information of the selected visible light communication light source. In general, the visible light communication light source performs visible light communication, and thus the light intensity fluctuates in a short time. However, in other light sources, the light intensity hardly fluctuates in a short time in many cases. Accordingly, if the light source other than the visible light communication light source is a light source such as an LED light source whose light intensity does not vary with time, the light intensity of the light source captured in the captured image varies. The light source is a visible light communication light source. Therefore, for example, the light source selection unit 1022 obtains position information of an image of a visible light communication light source that is an image of a light source whose light intensity varies with time from among the light source images detected by the light source detection unit 1021. May be.

  Here, the response speed of the image sensor 1011 which is an image sensor such as a CCD or CMOS is slower than that of a photodetector or the like, and the frequency of the electric signal detectable from the electric signal output from the image sensor 1011 is currently about 100 KHz. Thus, it is not possible to detect fluctuations in the electrical signal having a frequency of about 100 MHz as in the case of using a photodetector with a high response speed. Therefore, in the case where transmission target information modulated at a high frequency is transmitted by visible light communication in order to increase the bandwidth of visible light communication, the image processing means 1012 is used to transmit only the transmission target information. It is difficult to detect fluctuations in light intensity from light of optical communication. For this reason, the marker signal described above having a relatively low frequency is superimposed on information to be transmitted by visible light communication and transmitted from the visible light communication light source. This marker signal can also be detected from an electrical signal output from the image sensor 1011 having a slow response speed. For this reason, here, the light source selection unit 1022 separates and extracts a marker frequency signal, that is, a signal having the same frequency as the marker signal, from the electrical signal output from the image sensor 1011 according to the light transmitted from each light source, By determining whether or not this signal is a marker signal whose value varies, it is determined whether or not the light source is a visible light communication light source that transmits information superimposed with the marker signal by visible light communication.

  Specifically, the light source selection unit 1022 includes a light receiving element (not shown) included in an area in the image sensor 1011 corresponding to one of the areas that the light source detection unit 1021 determines to be a light source. An electric signal output in response to the incidence of light is continuously acquired for a predetermined time. The electrical signal output from the light receiving element included in the area corresponding to the light source in the image sensor 1011 is one or more light receiving elements included in the area corresponding to the light source among the plurality of light receiving elements constituting the image sensor 1011. May be a value obtained by adding an electrical signal output from the signal, or an average value of electrical signals output by a plurality of light receiving elements. The light source selection unit 1022 extracts marker frequency information from the electrical signal continuously acquired from one region. At this time, if one region is a visible light communication region, the obtained electrical signal is a signal of information obtained by superimposing transmission target information and a marker signal as described above.

  The light source selection unit 1022 acquires a predetermined number of voltage values at a predetermined sampling period from the extracted marker frequency information, and determines whether or not the acquired voltage values have changed. For example, it is determined whether the difference between the maximum value and the minimum value of the acquired voltage is equal to or greater than a threshold value. If the difference is equal to or greater than the threshold value, it is determined that fluctuation has occurred. Judge. When it is determined that fluctuation has occurred, for example, when the difference between the maximum value and the minimum value is greater than or equal to the threshold value, it can be considered that the electrical signal acquired from one region includes a marker signal. , It is determined that one region is a light source for visible light communication. Conversely, if no fluctuation occurs, it is determined that the light source is another light source whose light intensity does not change. Then, by performing the same processing for other regions that the light source detection unit 1021 determines to be light sources, it is possible to determine whether each light source captured in the captured image is a visible light communication light source. it can. Then, the light source selection unit 1022 acquires information indicating the position of the light source determined to be the visible light communication light source in the captured image as the position information of the visible light communication light source. In addition, instead of acquiring information indicating the position of the light source determined to be the visible light communication light source in the captured image as the position information of the visible light communication light source, the image sensor 1011 is the visible light communication light source. You may make it acquire the information which shows the position of the area | region which receives the light which injects from the determined light source as positional information on a visible light communication light source.

  In order to reliably detect the marker signal by a predetermined number of times of sampling, the frequency and pattern of the marker signal may be determined based on the relationship between the marker signal and the sampling period as described below, for example.

  FIG. 9 is a schematic diagram showing the relationship between the marker signal and the sampling period. In the figure, a sampling period 41 indicates the timing for sampling. Here, sampling is performed at regular time intervals. The marker signals 42a to 42j are signals having binary values “H” and “L”, respectively. Here, “H” is indicated by diagonal lines, and “L” is indicated by plain color. Here, assuming that the sampling interval indicated by the sampling period 41 is “1”, the period of the marker signals 42a to 42j and the ratio of the period in which the binary value that is the pattern of the marker signals 42a to 42j appears is represented. For example, the marker signal 42a is a signal whose frequency is 1/3 of the sampling period 41, the period of “H” is 1/3, and the period of “L” is 2/3. The marker signal 42b is a signal whose frequency is 1/3 of the sampling period 41, the period of “H” is 1/3, and the period of “L” is 1/3. The marker signal 42c is a signal whose frequency is ½ of the sampling period 41, the “H” period is ½, and the “L” period is 1.

  For example, in the marker signal 42a, when sampling is performed at the sampling period 41, only one data is always detected, for example, “H” only. For this reason, when the marker signal 42a is used, it is not possible to detect a marker signal that is a signal whose value varies. On the contrary, in the marker signal 42b, when sampling is performed at the sampling period 41, signals of “H” and “L” are detected alternately. Therefore, when the marker signal 42a is used, when the signal extracted at the marker frequency is a signal whose value fluctuates between “H” and “L”, the marker signal is detected. Therefore, the light source position detection unit 102 can determine whether the light source is a visible light communication light source. In order to reliably detect the marker signal by sampling a predetermined number of times, the sampling period may be changed. The light source selection unit 1022 can usually be realized by an MPU, a memory, or the like. The processing procedure of the light source selection unit 1022 is usually realized by software, and the software is recorded on a recording medium such as a ROM. However, it may be realized by hardware (dedicated circuit).

  When the image captured by the image capturing unit 101 is a moving image composed of a plurality of frame images, first, the light source detection unit 1021 has a high luminance from one frame image captured by the image sensor 1011. When a region has been detected and it is determined whether or not there is a variation in the brightness values acquired for each of the detected high-luminance regions for a plurality of frame images after that. One region may be determined as a light source for visible light communication in which the light intensity changes. In addition, when detecting the position of the visible light communication light source from the frame image in this way, as in the above, the change in the luminance of the visible light communication light source can be reliably detected using a plurality of frame images. It is necessary to set the pattern and frequency at which the value changes according to the frame rate of the captured image. In this case, it may be considered that the frame rate is the sampling rate described above.

  The information acquisition unit 103 acquires communication light incident position information, which is information on a position where light output from the visible light communication light source is incident, from the position information of the visible light communication light source acquired by the light source position detection unit 102. Information transmitted by visible light communication from the visible light communication light source is acquired at the position indicated by the communication light incident position information. The information transmitted by the visible light communication from the visible light communication light source is the above-described light source transmission target information. Specifically, the visible light communication light source described here is a visible light communication light source included in the optical wireless communication light source device 20. Specifically, the information acquisition unit 103 indicates a correspondence relationship between a region where light having passed through the first lens 111 is incident on the information acquisition unit 103 and a captured image obtained by photographing the light having passed through the first lens 111. Information is stored in a storage medium or the like in advance, and the information acquisition unit 103 corresponding to the position information of the visible light communication light source in the captured image acquired by the light source position detection unit 102 using the information indicating the correspondence relationship. Information on a position on a region where light having passed through the first lens 111 is incident is acquired. Then, only light incident on the acquired position is selectively received, and transmission target information is acquired from the received light. Specifically, the region where light having passed through the first lens 111 of the information acquisition unit 103 is incident is a region where light on a liquid crystal panel 10321 described later is incident. In addition, the information acquisition unit 103 receives light output from the visible light communication light source every time the light source position detection unit 102 acquires the position information of the visible light communication light source or the position information changes, for example. Communication light incident position information that is information indicating the position is acquired, and light source transmission target information transmitted from the visible light communication light source is acquired at the position indicated by the communication light incident position information.

  When the light source position detection unit 102 acquires communication light incident position information corresponding to two or more visible light communication light sources, the information acquisition unit 103 receives two or more visible light communication light sources from a reception unit (not shown). Receiving a selection instruction, which is an instruction to select any one of the position information, obtaining communication light incident position information corresponding to the position information of the visible light communication light source specified by the selection instruction, and entering the communication light You may make it acquire the transmission object information transmitted by visible light communication from the visible light communication light source in the position which position information shows. Moreover, you may make it acquire the communication light incident position information corresponding to the positional information of the visible light communication light source with the largest area in a picked-up image. Alternatively, the transmission target information may be alternately acquired at a specific timing or an unspecified predetermined timing at two or more positions indicated by communication light incident positions corresponding to two or more visible light communication light sources.

  Here, the information acquisition unit 103 includes an incident position information acquisition unit 1031, a selective transmission unit 1032, a second lens 113, a light receiving unit 1033, and an information acquisition unit 1034, which are used to generate a visible light communication light source. The case where the transmitted light is selectively received and the transmission target information transmitted from the visible light communication light source is acquired will be described below.

  The incident position information acquisition unit 1031 is a visible light communication light source in a region where light output from the visible light communication light source of the information acquisition unit 103 is incident based on the position information of the visible light communication light source acquired by the light source position detection unit 102. The communication light incident position information, which is information on the position where the light output from is incident, is acquired. Specifically, the photographed image taken by the photographing unit 101 and the shape of the area where the light that has passed through the first lens 111 in the information acquisition unit 103 is incident are similar, and the coordinate axes of the two are the first lens. 111, the coordinate information of the visible light communication light source of the photographed image is used by using the similarity ratio between the photographed image and the region where the light is incident. From the position information, the light source position information which is the coordinate information of the position where the light from the visible light communication light source is incident in the region where the light passing through the first lens 111 in the information acquisition unit 103 is incident is acquired. For example, when the position information is coordinate information, when the similarity ratio is 1: 1, the incident position information acquisition unit 1031 uses the coordinate information of the visible light communication light source in the captured image acquired by the light source position detection unit 102. As it is, the information acquisition unit 103 acquires the information as the coordinate information which is the information on the incident position in the region where the light is incident. Further, when the similarity ratio between the photographed image and the light incident area is 2 to 1, the values of the x-axis and y-axis of the coordinate information of the visible light communication light source in the photographed image are each 1/2. The obtained coordinate information is acquired as coordinate information that is information on an incident position in the region where light is incident in the information acquisition unit 103. That is, when the similarity ratio between the captured image and the light incident area is n (n is an arbitrary positive number) to 1, the x-axis and y-axis of the coordinate information of the visible light communication light source in the captured image The coordinate information whose value is 1 / n is acquired as coordinate information that is information on the incident position in the region where light is incident in the information acquisition unit 103. In addition, information that associates one or more pixels in the captured image with information indicating the position of the region where light is incident in the information acquisition unit 103, for example, coordinate information, is managed in advance. From the information, information indicating the position in the region where the light is incident in the information acquisition unit 103 corresponding to the pixel in which the visible light communication light source is detected in the captured image may be acquired as the communication light incident position information. . In the present embodiment, as will be described later, a case where the region where the light having passed through the first lens 111 of the information acquisition unit 103 is incident is a liquid crystal panel 10321 will be described as an example. For this reason, instead of using the coordinate information in the liquid crystal panel 10321 as the communication light incident position information, information specifying a pixel (not shown) in the liquid crystal panel 10321, for example, an ID or a number of the pixel may be used. . For example, information in which one or more pixels in the captured image are associated with one or more pixels in the liquid crystal panel 10321 is managed in advance, and the visible light communication light source in the captured image is determined based on the associated information. Information specifying the pixel of the liquid crystal panel 10321 corresponding to the detected pixel may be acquired. In addition, when the captured image captured by the imaging unit 101 and the shape of the region where the light that has passed through the first lens 111 in the information acquisition unit 103 is not completely similar, acquisition is performed according to the difference in shape. What is necessary is just to correct | amend position information. Note that the position information of the visible light communication light source acquired by the light source position detection unit 102 is position information of a part of the visible light communication light source such as the position information of the center position of the visible light communication light source in the captured image. In this case, the incident position information acquisition unit 1031 sets the area including the area around the position corresponding to the position information in the area where the light is incident in the information acquisition unit 103 as the communication light incident position. May be. The incident position information acquisition unit 1031 can be usually realized by an MPU, a memory, or the like. The processing procedure of the incident position information acquisition unit 1031 is usually realized by software, and the software is recorded on a recording medium such as a ROM. However, it may be realized by hardware (dedicated circuit).

  The selective transmission means 1032 selectively transmits only the light incident on the position indicated by the communication light incident position information acquired by the incident position information acquisition means 1031 among the light incident through the first lens 111. Specifically, the selective transmission means 1032 has a filter, an aperture, or the like that can form a region that can transmit light only in an arbitrary region within the region where the light having passed through the first lens 111 is incident. By controlling the filter and the diaphragm, an area where light can be transmitted is formed only at the position indicated by the incident position information acquired by the incident position information acquiring unit 1031. Here, a case where the selective transmission means 1032 includes the liquid crystal panel 10321 and the light shielding control means 10322 and the above processing is performed using these will be described.

  The liquid crystal panel 10321 changes the orientation of the liquid crystal by applying a voltage to the liquid crystal with a plurality of arranged electrodes, and controls whether to transmit light for each segment provided with the electrode, thereby transmitting light. The shape of the area to be controlled can be controlled. Here, for example, a liquid crystal panel in which segments are arranged in a lattice shape is used. This segment is called a pixel here. The liquid crystal panel 10321 may be a color liquid crystal panel such as an RGB color, or a binary or gray scale liquid crystal panel such as black and white. The liquid crystal panel 10321 only needs to be able to display two colors, a color that allows light to pass through and a color that does not allow light to pass, and the number of gradations that can be displayed only needs to be two or more. By using a color liquid crystal panel as the liquid crystal panel 10321, the color of the region through which light is transmitted can be set to an arbitrary color, for example, blue. By doing in this way, it becomes possible to permeate | transmit only the arbitrary colors of the light from a visible light communication light source, for example, only blue. The liquid crystal panel 10321 is disposed at a position where light having passed through the first lens 111 is incident.

  The light blocking control unit 10322 controls the liquid crystal panel 10321 so that a region other than the incident position indicated by the incident position information acquired by the incident position information acquiring unit 1031 of the liquid crystal panel 10321 is a region that blocks light. In this case, the incident position information acquired by the incident position information acquiring unit 1031 is preferably information that can specify one or more pixels of the liquid crystal panel 10321. Specifically, a control signal for controlling each pixel of the liquid crystal panel 10321 is output to the liquid crystal panel 10321, and the pixel of the liquid crystal panel 10321 corresponding to the communication light incident position acquired by the incident position information acquisition unit 1031 transmits light. The liquid crystal panel 10321 is controlled so as to be a possible pixel and pixels in other regions to be pixels that block light. As a result, of the light incident on the liquid crystal panel 10321 through the first lens 111, only the light input to the communication light incident position, that is, only the light from the visible light communication light source is transmitted through the liquid crystal panel 10321. Become. A transmissive pixel is a pixel that can transmit light from visible light communication. The transmissive pixel may be, for example, a pixel that is transparent or translucent, or may be a pixel that transmits only a specific color of light. For example, when the liquid crystal panel 10321 is a color liquid crystal panel, the pixel corresponding to the communication light incident position acquired by the incident position information acquisition unit 1031 of the liquid crystal panel 10321 is set as a blue pixel, and the other area is set as black or the like. Thus, only blue light can be selectively transmitted from the pixel position corresponding to the communication light incident position. The shading control means 10322 can be usually realized by an MPU, a memory, or the like. The processing procedure of the shading control means 10322 is usually realized by software, and the software is recorded on a recording medium such as a ROM. However, it may be realized by hardware (dedicated circuit).

  The second lens 113 is a condensing unit for condensing the light transmitted through the selective transmission unit 1032, specifically, the liquid crystal panel 10321 and causing the light to enter the light receiving unit 1033. The second lens 113 needs to be installed so that light transmitted through any position of the selective transmission means 1032, specifically, the liquid crystal panel 10321 is incident on the light receiving means 1033. Instead of the second lens 113, other condensing means such as a concave mirror may be provided. Further, when the light transmitted through the selective transmission unit 1032 can be incident on the light receiving unit 1033 without being condensed, such as when the size of the light receiving unit 1033 is sufficiently large, the second lens 113 can be omitted. is there.

  The light receiving means 1033 receives light incident on the incident position indicated by the incident position information and converts it into an electrical signal. Specifically, light selectively extracted by the selective transmission means 1032, specifically, the liquid crystal panel 10321 is collected by the second lens 113 and is incident on the light receiving means 1033. The light receiving means 1033 converts the intensity of the incident light in this way into an electric signal. The light receiving means 1033 is a light receiving element having a high response speed, specifically a photodetector. The light receiving means 1033 may be composed of a plurality of photodetectors as long as it functions as a single photodetector. By using one photodetector as the light receiving means 1033, light can be converted into an electrical signal at high speed, and visible light communication light that fluctuates at high speed can be received with high accuracy.

  The information acquisition unit 1034 acquires information transmitted by visible light communication from the electrical signal converted by the light receiving unit 1033. For example, the information acquisition unit 1034 demodulates the electrical signal converted by the light receiving unit 1033 at a predetermined frequency specified in advance, and extracts information. Further, AD conversion or the like may be appropriately performed on the extracted information. The configuration and the like of the information acquisition unit 1034 are the same as the information acquisition unit and the like used in a receiving terminal of a normal visible light communication system, and thus detailed description thereof is omitted. The information acquisition unit 1034 can usually be realized by an MPU, a memory, or the like. The processing procedure of the information acquisition unit 1034 is usually realized by software, and the software is recorded on a recording medium such as a ROM. However, it may be realized by hardware (dedicated circuit).

  The output unit 104 outputs the information acquired by the information acquisition unit 103. Specifically, the terminal transmission target information acquired by the information acquisition unit 103 is output. Output described here includes display on a display, printing on a printer, sound output, transmission to an external device, storage in a recording medium, delivery of processing results to another processing device or other program, etc. It is a concept that includes. The output unit 104 may or may not include an output device such as a display or a printer. The output unit 104 can be implemented by output device driver software, or output device driver software and an output device.

  The terminal transmission target information receiving unit 105 receives information to be transmitted by the optical wireless communication terminal device 10 through visible light communication. This information to be transmitted is called terminal transmission target information here. The terminal transmission target information is, for example, information transmitted using the optical wireless communication light source device 20 as a transmission destination. The terminal transmission target information may be any information such as image information, text information, identification information of the optical wireless communication terminal device 10 itself, or identification information of the user. The reception described here is, for example, reception from an input unit, reception of an input signal transmitted from another device, reading of information from a recording medium, or the like. The terminal transmission target information input means may be anything such as a numeric keypad, keyboard, mouse or menu screen. The terminal transmission target information receiving unit 105 can be realized by a device driver for input means such as a numeric keypad or a keyboard, control software for a menu screen, and the like.

  The transmission light source 106 includes a light emitter (not shown) such as an LED, an incandescent lamp, or a fluorescent lamp. The transmission light source 106 is a light source for transmitting information by visible light communication. The transmission light source 106 may be any light source such as a flashlight. However, in order to increase the amount of information to be transmitted, it is preferable to use, for example, an LED that can blink at high speed. The emission intensity of the transmission light source 106 is adjusted by adjusting the voltage supplied to the transmission light source 106. The intensity of the light emitted from the transmission light source 106 is varied according to the information received by the terminal transmission target information receiving unit 105, for example, by blinking, so that the information received by the terminal transmission target information receiving unit 105 is visible light communication. Can be transmitted.

  The terminal transmission target information transmission unit 107 transmits the terminal transmission target information received by the terminal transmission target information reception unit 105 from the transmission light source 106 by visible light communication. The terminal transmission target information transmission unit 107 can be realized by a communication unit or the like used for general visible light communication. In this specific example, a case where the terminal transmission target information transmission unit 107 performs transmission processing using the modulation unit 1071 and the transmission unit 1072 will be described as an example.

  Modulating means 1071 modulates terminal transmission target information received by terminal transmission target information receiving section 105 with a predetermined frequency. The frequency to be modulated here is a frequency that can be processed by the light receiving means of the optical wireless communication light source device 20, and is preferably a frequency at which a sufficient data transfer rate can be obtained. For example, the frequency to be modulated is a frequency of several tens to several hundreds of MHz.

  The transmission unit 1072 controls the transmission light source 106 according to the terminal transmission target information modulated by the modulation unit 1071, and transmits the terminal transmission target information from the transmission light source 106 by visible light communication. For example, the terminal transmission target information is output from the light source 106 by supplying the terminal transmission target information modulated by the modulation unit 1071 to the transmission light source 106.

  FIG. 3 is a block diagram for explaining the configuration of the optical wireless communication light source device 20. The optical wireless communication light source device 20 includes a terminal transmission target information reception unit 201, an identification information storage unit 202, a reception information transmission unit 203, a light source transmission target information reception unit 204, one or more visible light communication light sources 205, and light source transmission target information. A transmission unit 206 is provided.

  The terminal transmission target information receiving unit 201 includes a light receiving unit 2011 and an information acquiring unit 2012.

  The light source transmission target information transmission unit 206 includes a modulation unit 2061, a marker signal output unit 1062, a superimposition unit 2063, and a transmission unit 2064.

  The terminal transmission target information receiving unit 201 receives terminal transmission target information transmitted from the optical wireless communication terminal apparatus 10 by visible light communication. Specifically, light output from the transmission light source 106 of the optical wireless communication terminal device 10 is received, and terminal transmission target information is extracted from the received light. The terminal transmission target information receiving unit 201 only needs to have the same configuration as the receiving unit of a normal visible light communication apparatus. Here, as an example, a case will be described in which the terminal transmission target information reception unit 201 receives terminal transmission target information transmitted by visible light communication using the light receiving unit 2011 and the information acquisition unit 2012.

  The light receiving unit 2011 receives light output from the transmission light source 106 of the optical wireless communication terminal apparatus 10 and converts it into an electrical signal. The configuration of the light receiving unit 2011 is the same as that of the light receiving unit 1033 described above except that the incident light is different. The optical wireless communication light source device 20 has a lens (not shown) for condensing the light output from the transmission light source 106 of the optical wireless communication terminal device 10 and inputting it to the light receiving surface of the light receiving means 1033. You may have. This lens may be, for example, the same lens as the first lens 111 and the second lens 113 described above. The light receiving means 2011 is preferably arranged in the vicinity of the visible light communication light source 205.

  The information acquisition unit 2012 acquires terminal transmission target information transmitted by visible light communication from the electrical signal converted by the light receiving unit 2011. Since the configuration of the information acquisition unit 2012 is the same as that of the information acquisition unit 1034 described above, detailed description thereof is omitted.

  The identification information storage unit 202 can store identification information that is information for identifying the device itself. The identification information for identifying the device itself may be any information, such as the MAC address of the optical wireless communication light source device 20, address information on the network, or the like. It may be information indicating a physical position in which it is arranged. Also, it may be unique information assigned to the optical wireless communication light source device. The process of accumulating identification information does not matter. The identification information storage unit 202 is preferably a non-volatile recording medium, but can also be realized by a volatile recording medium.

  The reception information transmitting unit 203 transmits the terminal transmission target information received by the terminal transmission target information receiving unit 201 in association with the identification information of the own device. Specifically, the reception information transmission unit 203 reads the identification information of the own device stored in the identification information storage unit 202, and transmits the identification information in association with the terminal transmission target information. Note that the identification information and the terminal transmission target information only need to be transmitted so that it can be understood that they are associated with each other. For example, the identification information and the terminal transmission target information are combined into one transmission information. The identification information and the terminal transmission target information may be transmitted separately together with the information for managing the correspondence. The reception information transmission unit 203 performs transmission via a network, a power communication line, or the like. The transmission destination is, for example, the server 30. The reception information transmitting unit 203 is preferably a wireless communication unit, but can also be realized by a broadcast receiving unit or a wired communication unit. In addition, when transmission is performed by power line communication via a power communication line, the reception information transmission unit 203 may include a so-called power line communication modem or the like.

  If the reception information transmitting unit 203 does not need to transmit the identification information of its own device, the identification information storing unit 202 may be omitted so that the identification information is not transmitted in association with the terminal transmission target information. Also good.

  The light source transmission target information receiving unit 204 receives light source transmission target information that is information to be transmitted to the optical wireless communication terminal device 10. The light source transmission target information receiving unit 204 receives light source transmission target information transmitted from the server 30 or the like via a network, a power communication line, or the like. The light source transmission target information receiving unit 204 is preferably a wireless communication unit, but can also be realized by a broadcast receiving unit or a wired communication unit. Moreover, when receiving via a power communication line by power line communication, the light source transmission target information receiving unit 204 may include a so-called modem for power line communication.

  The visible light communication light source 205 is a light source that performs visible light communication for transmitting light source transmission target information. The configuration of the visible light communication light source 205 is the same as that of the transmission light source 106, and thus description thereof is omitted here.

  The light source transmission target information transmission unit 206 transmits the light source transmission target information received by the light source transmission target information reception unit 204 from the visible light communication light source 205 by optical wireless communication. In this embodiment, in particular, a case will be described in which the light source transmission target information transmission unit 206 further outputs the above-described marker signal in addition to the light source transmission target information. The light source transmission target information transmission unit 206 can be realized by communication means used for general visible light communication. In this specific example, a case where the light source transmission target information receiving unit 204 performs transmission processing using the modulation unit 2061, the marker signal output unit 2062, the superimposition unit 2063, and the transmission unit 1064 is taken as an example. I will explain.

  The modulation unit 2061 modulates the light source transmission target information acquired by the light source transmission target information receiving unit 204 with a predetermined frequency. The frequency to be modulated here is preferably a frequency that can be processed by the light receiving means 1033 such as a photodetector of the optical wireless communication terminal device 10 described above, and a frequency at which a sufficient data transfer rate can be obtained. For example, the frequency to be modulated is a frequency of several tens to several hundreds of MHz.

  The marker signal output unit 2062 outputs a marker signal that is information used by the optical wireless communication terminal apparatus 10 to detect the position of the visible light communication light source 205. The marker signal is a signal having a frequency that can be received by the image sensor 1011 such as an image sensor of the optical wireless communication terminal device 10 as described with reference to FIG. 9. This frequency is, for example, about several tens KHz to several hundred KHz. The marker signal is information that changes the magnitude of the signal in, for example, a certain pattern. The marker signal output means 2062 may generate a marker signal having a predetermined frequency, or read out a digital marker signal stored in advance in a storage medium (not shown), etc., modulates it at a predetermined frequency, and outputs it. May be.

  The superimposing unit 2063 superimposes one or more modulated light source transmission target information output from the modulating unit 2061 and the marker signal output from the marker signal output unit 2062.

  The transmission unit 2064 controls the visible light communication light source 205 in accordance with the light source transmission target information and the marker signal superimposed by the superimposing unit 2063, and the visible light communication light source 205 makes the light source transmission target information and the marker signal visible. Transmit by light. For example, the transmitting unit 2064 supplies the visible light communication light source 205 with the voltage corresponding to the terminal transmission target information and the marker signal superimposed by the superimposing unit 2063, so that the light source transmission target information and the marker signal are transmitted from the visible light communication light source 205. Outputs light according to.

  In addition, when the optical wireless communication terminal device 10 does not detect the position of the visible light communication light source 205 using the marker signal, the configuration for transmitting the marker signal of the light source transmission target information transmission unit 206 may be omitted. For example, the marker signal output unit 2062 and the superimposing unit 2063 may be omitted.

  Further, when the marker signal and the light source transmission target information are transmitted in time division, the superimposing unit 2063 may be omitted.

  FIG. 4 is a block diagram for explaining the configuration of the server 30. The server 30 includes a server storage unit 301, a server information acquisition unit 302, a server transmission unit 303, a server reception unit 304, and a server processing unit 305.

  Note that the server 30 shown here is an example, and in the present invention, the server 30 receives the information transmitted by the reception information transmitting unit 203 of the optical wireless communication light source device 20 and sends it to the optical wireless communication light source device 20. As long as it is a device capable of transmitting information, a device having a configuration other than the above may be used.

  The server storage unit 301 can store one or more pieces of light source transmission target information. It does not matter what kind of information the light source transmission target information is. The server storage unit 301 is preferably a nonvolatile recording medium, but can also be realized by a volatile recording medium.

  The server information acquisition unit 302 acquires the light source transmission target information stored in the server storage unit 301. It does not matter how the server information acquisition unit 302 determines the light source transmission target information to be read. For example, light source transmission target information determined by a server processing unit 305, which will be described later, may be read out, or light source transmission target information may be read out according to a predetermined order. Further, the server information acquisition unit 302 may configure and acquire new light source transmission target information using the light source transmission target information stored in the server storage unit 301. For example, the server information acquisition unit 302 may create information indicating a list of light source transmission target information stored in the server storage unit 301 and acquire the information of this list as light source transmission target information. The server information acquisition unit 302 can be usually realized by an MPU, a memory, or the like. The processing procedure of the server information acquisition unit 302 is usually realized by software, and the software is recorded on a recording medium such as a ROM. However, it may be realized by hardware (dedicated circuit).

  The server transmission unit 303 transmits the light source transmission target information acquired by the server information acquisition unit 302 to the optical wireless communication light source device 20 via a network, a power communication line, or the like. The server transmission unit 303 can be realized by communication means used for general visible light communication. Further, when transmission is performed via a power communication line by power line communication, the server transmission unit 303 may include a so-called power line communication modem or the like.

  The server reception unit 304 receives terminal transmission target information transmitted from the optical wireless communication light source device 20 and identification information of the optical wireless communication light source device 20 via a network, a power communication line, or the like. The server reception unit 304 can be realized by a communication unit or the like used for general visible light communication. Further, when receiving via the power communication line by power line communication, the server reception unit 304 may include a so-called modem for power line communication.

  The server processing unit 305 performs predetermined processing on the terminal transmission target information and identification information received by the server receiving unit 304. This predetermined process may be any process, may be a process of accumulating received terminal transmission target information and identification information in a storage medium (not shown), or the terminal transmission target from the received identification information. The optical wireless communication light source device 20 that has received the information or the position of the optical wireless communication light source device 20 may be detected, and the position information may be acquired. The optical wireless communication light source device 20 that has received the terminal transmission target information from the received identification information. Server information acquisition unit 302 so as to read out and transmit the light source transmission target information corresponding to the received terminal transmission target information from the server storage unit 301 to the detected optical wireless communication light source device 20. Or a process for controlling the server transmission unit 303 or the like. The server processing unit 305 can usually be realized by an MPU, a memory, or the like. The processing procedure of the server processing unit 305 is usually realized by software, and the software is recorded on a recording medium such as a ROM. However, it may be realized by hardware (dedicated circuit).

  Next, the operation of the optical wireless communication terminal apparatus 10 in the present embodiment will be described using the flowchart of FIG. Here, from the visible light communication light source 205 of the optical wireless communication light source device 20, information in which a marker signal having a different frequency and light source transmission target information that is a target of visible light communication are superimposed is transmitted by visible light communication. A case will be described as an example.

  (Step S501) The imaging unit 101 captures an image and acquires a captured image. The captured image may be a still image or a moving image composed of a plurality of frame images.

  (Step S502) The light source position detection unit 102 acquires position information of the visible light communication light source in the captured image acquired in step S501. Details of this processing will be described later.

  (Step S503) The incident position information acquisition unit 1031 acquires communication light incident position information corresponding to the position information of the visible light communication light source acquired in Step S502. Specifically, using information indicating the correspondence between the captured image and the liquid crystal panel, the position information on the liquid crystal panel 10321 corresponding to the position of the visible light communication light source in the captured image is obtained from the position information of the visible light communication light source. get.

  (Step S504) The light blocking control unit 10322 controls the liquid crystal panel 10321 using the communication light incident position information acquired in step S503, and light is transmitted only through the pixel at the position indicated by the communication light incident position information of the liquid crystal panel 10321. As a possible state, pixels in other regions are made to block light. For example, the liquid crystal panel 10321 displays an image in which only the region indicated by the communication light incident position information is a transmissive region and the other regions are black that does not transmit light. As a result, only the light output from the visible light communication light source is transmitted through the region constituted by the pixel at the position indicated by the communication light incident position information of the liquid crystal panel 10321, and the other light is blocked by the liquid crystal panel 10321.

  (Step S505) The information acquisition unit 1034 starts acquisition of information transmitted by visible light communication from the electrical signal output by the light receiving unit 1033 that has received the light transmitted through the liquid crystal panel 10321. The acquired information is temporarily stored in a storage medium such as a memory (not shown).

  (Step S506) The terminal transmission target information reception unit 105 determines whether terminal transmission target information has been received. If accepted, the process proceeds to step S507. If not accepted, the process proceeds to step S508.

  (Step S507) The terminal transmission target information transmitting unit 107 modulates the terminal transmission target information received in Step S506, and transmits the modulated information from the transmission light source 106 by visible light communication.

  (Step S508) The optical wireless communication terminal apparatus 10 determines whether to stop receiving light source transmission target information and terminal transmission target information transmitted by visible light communication. The optical wireless communication terminal apparatus 10 may determine whether to receive the light source transmission target information and stop transmitting the terminal transmission target information according to any trigger. For example, when an instruction to stop transmission / reception is received from an unillustrated reception unit or the like, it may be determined to stop transmission / reception, or when an instruction to turn off the optical wireless communication terminal device 10 is received, If the optical wireless communication terminal device 10 is in a standby state after a predetermined time has elapsed without any operation, it may be determined to stop reception. If the reception is to be canceled, the process is terminated. If the reception is not to be canceled, the process returns to step S501.

  If it is determined in step S508 that transmission / reception is not stopped, the same communication light incident position information is returned to step S505 until a predetermined time elapses after the position of the visible light communication light source is acquired. The transmission target information may be repeatedly acquired at the position indicated by, and when a predetermined time has elapsed, the process returns to step S501 and the position of the visible light source may be acquired again.

  Further, when it is determined in step S508 that transmission / reception is not stopped, the process returns to step S501. However, the information acquisition unit 103 started in step S505 is visible even during the subsequent processing after step S501. You may make it perform the process which receives the information transmitted by optical communication in parallel.

  Note that immediately after step S502, the incident position information acquisition unit 1031 may determine whether or not the position information of a plurality of visible light communication light sources has been acquired in step S502. Then, when the position information of a plurality of visible light communication light sources is acquired, the position information of one visible light communication light source is selected from the plurality of visible light communication light sources, and the selected visible light communication is performed. Communication light incident position information corresponding to the position information of the light source may be acquired. For selecting the position information of the visible light communication light source, for example, an instruction to select one of the visible light communication light sources from the user is accepted, and the position information of the visible light communication light source corresponding to the instruction is selected. Also good. Moreover, you may make it select the position information of any one visible light communication light source according to the rule designated beforehand. This rule may be any rule, for example, position information may be selected at random, or position information closer to the center of the captured image may be selected. Moreover, you may make it select the one where the intensity | strength of the light obtained from each positional information is higher. Further, the position information of the visible light communication light source having the largest size may be selected. If position information of a plurality of visible light communication light sources has not been acquired, the process may proceed to step S503.

  Next, details of processing for acquiring position information of the visible light communication light source using the above-described captured image will be described using the flowchart of FIG. This process is a process corresponding to the process of step S502.

  (Step S601) The light source detection unit 1021 detects a light source in the captured image acquired in step S501 described above. As a specific example, a light source is usually composed of pixels with a high luminance value in a photographed image, and therefore, for each pixel constituting the photographed image, a light value and a pixel constituting the light source are discriminated. The threshold is sequentially compared. Then, a pixel having a luminance value equal to or higher than the threshold is determined to be a light source pixel. A region in which pixels determined to be light source pixels continuously exist is sequentially detected as one light source. Then, the coordinate information of each pixel constituting the light source is stored in a storage medium (not shown) in association with identification information for identifying the light source, for example. Here, a set of coordinate information of one or more pixels constituting one light source is set as position information indicating the position of the one light source. It should be noted that the center coordinates, the barycentric coordinates, the coordinates defining the contour, and the like of the area constituting one light source may be used as the light source position information. The position of the light source may be detected by other methods. For example, when the shape of the light source is determined in advance, it may be detected by performing pattern matching on the shape of the light source. Note that the captured image used here may be a still image or an image of one frame in a moving image, or may be an image obtained by combining a plurality of moving image images. Although the brightness value of the captured image is used here, the light source may be detected based on the color or the like in the captured image, or the value of a specific channel in the captured image, for example, R channel or G The light source may be detected using the channel and B channel values.

  (Step S602) The light source selection unit 1022 substitutes 1 for the counter q.

  (Step S603) The light source selection unit 1022 determines whether or not the qth light source is present in the light sources detected in step S601. If there is, the process proceeds to step S604. If not, the acquired information on the position of the visible light communication light source is returned to the upper process.

  (Step S604) The light source selection unit 1022 acquires an electric signal obtained at a position corresponding to the q-th light source of the image sensor 1011. Specifically, the light source selection unit 1022 acquires an electrical signal output from one or more light receiving elements arranged at a position corresponding to the position of the qth light source in the captured image of the imaging element 1011. In addition, since the captured image is created from the electrical signal output from each light receiving element of the image sensor 1011, the position of each pixel in the captured image and one or more electrical signals that are used to create the pixel are output. Since the correspondence relationship with the position of the light receiving element is designated in advance, it is possible to acquire the position of the light receiving element corresponding to the pixel constituting the qth light source by using information indicating this correspondence relationship. is there. Here, unlike the case of shooting, the electric signal output from the image sensor 1011 is continuously acquired without scanning the image sensor 1011. Thereby, the light output from the q-th light source can be converted into a continuous electric signal.

  (Step S605) The light source selection unit 1022 acquires a signal having a marker frequency, which is the frequency of the marker signal, from the electrical signal acquired from Step S603. In addition, since the technique which takes out the signal of a predetermined frequency from an electrical signal is a well-known technique, description is abbreviate | omitted here.

  (Step S606) The light source selection unit 1022 samples, or digitizes, the electrical signal acquired in Step S605 at a predetermined cycle specified in advance.

  (Step S607) The light source selection unit 1022 determines whether or not a predetermined time has elapsed from the start of the process of step S604 for the qth light source. Specifically, the predetermined time is information that specifies a period during which a signal for detecting a marker signal is received from one light source. If the predetermined time has elapsed, the process proceeds to step S608, and if not, the process returns to step S603. Note that after the electrical signal output from the image sensor 1011 is received for a predetermined time, the received electrical signal may be sampled.

  (Step S608) The light source selection unit 1022 detects whether or not the signal acquired at the marker frequency is a marker signal. The detection of the marker signal here may be considered as detecting the detection of a signal whose signal magnitude is characteristic of the marker signal. Specifically, in step S606, the light source selection unit 1022 determines whether or not the intensity value of the electrical signal acquired by sampling within the predetermined time described above has fluctuated. It is determined that the signal is a marker signal, and if it is not changed, it is determined that the signal is not a marker signal. Whether or not it fluctuates may be determined in any way. For example, it fluctuates when the difference between the maximum value and the minimum value of values sampled within a predetermined time is larger than a preset threshold value. You may judge that Alternatively, it may be determined that the sampled value fluctuates when at least one value greater than a preset maximum value and one less than a preset minimum value are included. If the marker signal is detected, the process proceeds to step S609, and if the marker signal is not detected, the process proceeds to step S610.

  (Step S609) The light source detection unit 1021 acquires information on the position of the qth light source among the light sources detected in step S601 as position information of the visible light communication light source. For example, the coordinate information of one or more pixels constituting the qth light source is acquired as the position information of the visible light communication light source. Then, the acquired position information is temporarily stored in a storage medium (not shown) or the like in association with, for example, information for identifying the visible light communication light source. The temporarily stored position information of the visible light communication light source is the position information of the visible light communication light source acquired by the light source position detection unit 102.

  (Step S611) The light source selection unit 1022 increments the value of the counter q by 1. Then, the process returns to step 303.

  In the flowchart described with reference to FIG. 5, once the position of the visible light communication light source is detected, the image capturing unit 101 repeatedly captures an image as shown in step S <b> 501, and the above-described image is obtained in the newly acquired captured image. Similarly to the processing in step S601, the position of the light source is newly detected from the luminance of the pixel and the like, and the newly detected light source has a high correlation with the visible light communication light source detected immediately before or has been detected immediately before. You may make it detect the light source etc. with the shortest distance with a visible light communication light source as a position of the visible light communication light source in the newly image | photographed image. The visible light communication information may be received using the detected position information of the visible light communication light source. As a result, even when the position of the visible light communication light source changes, it is possible to detect the position after the change at high speed and to receive information communicated by visible light following the change in position.

  Next, the operation of the optical wireless communication light source device 20 will be described using the flowchart of FIG.

  (Step S701) The light source transmission target information receiving unit 204 determines whether or not the light source transmission target information has been received via a network or the like. If received, the process proceeds to step S702. If not received, the process proceeds to step S704.

  (Step S702) The light source transmission target information transmission unit 206 superimposes the light source transmission target information received in step S701 and the marker signal output by the marker signal output unit 2062.

  (Step S <b> 703) The light source transmission target information transmission unit 206 transmits the information obtained by superimposing in step S <b> 702 by visible light using the visible light communication light source 205. Then, the process returns to step S701.

  (Step S704) The terminal transmission target information receiving unit 201 determines whether terminal transmission target information has been received. Specifically, it is determined whether the information acquisition unit 2012 has received the terminal transmission target information from the light received by the light receiving unit 2011. If received, the process proceeds to step S705. If not received, the process returns to step S701.

  (Step S <b> 705) The reception information transmission unit 203 reads the identification information from the identification information storage unit 202.

  (Step S706) The reception information transmitting unit 203 associates the terminal transmission target information received in Step S704 with the identification information received in Step S705, and transmits it to the server 30. Thereby, from the associated identification information, the server 30 or the like can detect which optical wireless communication light source device 20 has received the terminal transmission target information. Then, the process returns to step S701.

  In the flowchart of FIG. 7, the process ends when the power is turned off or the process ends.

  Next, the operation of the server 30 will be described using the flowchart of FIG.

  (Step S801) The server information acquisition unit 302 determines whether to transmit light source transmission target information. The server information acquisition unit 302 may determine whether to transmit the light source transmission target information according to any timing or trigger. For example, when a predetermined timing or the like is reached, it may be determined to transmit light source transmission target information designated in advance. In addition, when the server reception unit 304 receives terminal transmission target information including an instruction to transmit light source transmission target information, it may be determined to transmit the light source transmission terminal information. Further, transmission of the light source transmission terminal information may be determined under the control of the server processing unit 305. When transmitting, it progresses to step S802, and when not transmitting, it progresses to step S804.

  (Step S <b> 802) The server information acquisition unit 302 reads the light source transmission target information from the server storage unit 301. For example, the server information acquisition unit 302 reads light source transmission target information designated by a preset schedule or an instruction output by the server processing unit 305.

  (Step S803) The server transmission unit 303 transmits the light source transmission target information read in step S802. The server transmission unit 303 may determine how to transmit the light source transmission target information. For example, the light source transmission target information may be transmitted to one or more optical wireless communication light source devices 20 specified in advance, or identification information associated with the terminal transmission target information received by the server reception unit 304 is indicated. The light source transmission target information may be transmitted only to the optical wireless communication light source device 20. Then, the process returns to step S801.

  (Step S804) The server reception unit 304 determines whether or not terminal transmission target information has been received. If received, the process proceeds to step S805. If not received, the process returns to step S801.

  (Step S805) The server processing unit 305 acquires the identification information transmitted in association with the terminal transmission target information received in step S804.

  (Step S806) The server processing unit 305 performs a predetermined process according to the terminal transmission target information and the identification information received in steps S804 and S805. This process may be any process. For example, when the terminal transmission target information is information that requests certain light source transmission target information, the server processing unit 305 instructs the server information acquisition unit 302 to acquire the requested information from the server storage unit 301. May be output to the server information acquisition unit 302. And the instruction | indication which transmits the information which the server information acquisition part 302 acquired to the server transmission part 303 according to this instruction | indication to the optical wireless communication light source device 20 which the identification information acquired in step S805 shows may be output. . Then, the process returns to step S801.

  In the flowchart of FIG. 8, the process ends when the power is turned off or the process is terminated.

  Hereinafter, a specific operation of the optical wireless communication system in the present embodiment will be described. A conceptual diagram of the optical wireless communication terminal apparatus is shown in FIG.

  FIG. 10 is a schematic diagram for explaining a specific example of the optical wireless communication system. Here, it is assumed that the optical wireless communication terminal device 10 constitutes at least a part of an optical wireless communication portable terminal 10a which is a portable portable terminal. The optical wireless communication portable terminal 10a is, for example, a telephone, a PDA, a portable music player, a portable video player, or the like. As an example, the optical wireless communication terminal apparatus 10 includes a display device 1051 that is an output device. It is assumed that a transmission light source 106 is provided next to the first lens 111 of the optical wireless communication portable terminal 10a. Here, it is assumed that the transmission light source 106 is a flashlight composed of LEDs. In addition, it is assumed that LED light sources 51 to 54 are installed on the ceiling of the room where the optical wireless communication terminal device 10 exists. Here, in particular, it is assumed that the LED light source 51 is the visible light communication light source 205 of the optical wireless communication light source device 20. The optical wireless communication light source device 20 is assumed to be communicably connected to the server 30 by power line communication (PLC) or the like. Further, it is assumed that the light receiving means 2011 of the optical wireless communication light source device 20 is installed downward next to the LED light source 51.

  Here, in the server 30 in the server 30, as the light source transmission target information, program information that is information of a plurality of television programs that the server 30 can provide to the user in advance, and a list of the program information that can be provided It is assumed that basic information, which is information indicating, is stored. The program information is, for example, moving image information.

  FIG. 11 is a diagram showing an example of a program information management table for managing program information stored in the server storage unit 301. The program information management table has items of “program ID” and “program data”. “Program ID” is identification information for managing program information. “Program information” is program information of a television program to be transmitted.

  FIG. 12 is a diagram illustrating an example of basic information stored in the server storage unit 301. The basic information includes items “program name”, “program ID”, and “preview”. “Program name” is the name of the program that is the content. “Program ID” is program identification information. “Preview” is a preview image of a television program to be transmitted. The “program ID” corresponds to the “program ID” in FIG. The format of basic information is not limited.

  First, the server information acquisition unit 302 acquires basic information as illustrated in FIG. 12 from the server storage unit 301. And the server transmission part 303 transmits the basic information which the server information acquisition part 302 acquired to the optical wireless communication light source device 20 via an electric power communication line (not shown). This basic information is one of the light source transmission target information.

  The light source transmission target information receiving unit 204 of the optical wireless communication light source device 20 receives basic information that is light source transmission target information transmitted from the server 30 via the power communication line. The light source transmission target information transmission unit 206 modulates the received basic information, superimposes the marker information, and transmits the basic information from the visible light communication light source 205 by visible light communication. Here, the frequency of the marker signal is 28.8 KHz, and the frequency of the basic information is 40 MHz. The transmission of basic information is assumed to be repeated here.

  Next, when the user holds the first lens 111 facing the ceiling, for example, when the power is turned on, the photographing unit 101 of the optical wireless communication terminal device 10 causes the image of the ceiling to pass through the first lens 111. Shoot. Here, the number of pixels of the image captured by the image capturing unit 101 is assumed to be 320 × 240 pixels as an example for the sake of explanation. Note that the greater the number of pixels, the more accurately the light source is detected, but the processing is slowed accordingly.

  FIG. 13 is a diagram illustrating a captured image captured by the capturing unit 101. In this captured image, all LED light sources that are lit are photographed. In the figure, the same reference numerals as those in FIG. 10 indicate images of the same light source. In the image of FIG. 13, the upper left is the coordinate (0, 0), the right direction of the coordinate is the x-axis direction, and the lower direction of the coordinate is the y-axis direction. The unit of coordinates is assumed to be pixels.

  Next, the light source detection unit 1021 acquires a captured image, and detects a light source in the captured image. Here, the luminance value of each pixel of the photographed image is compared with a threshold value of a luminance value specified in advance, and a pixel having a luminance value equal to or higher than the threshold value is determined as a light source pixel. Here, it is assumed that the luminance is higher as the luminance value is larger. Then, it is determined that a region where luminance values equal to or greater than the threshold value are continuous is one light source.

  For example, if the acquired photographed image is a still image as shown in FIG. 13, an area where pixels having a luminance value equal to or higher than the threshold value of this image are white, and an area where pixels having a luminance value less than the threshold value are present. FIG. 14 shows an oblique line, that is, this image binarized by the threshold value of the luminance value. By the process of detecting the light source as described above, it is determined that the four independent areas 51a to 54a represented in white in FIG. 14 are the light sources. The areas 51a to 54a are areas corresponding to the light sources 51 to 54, respectively.

  The detected coordinate information of the pixels constituting each light source is temporarily stored in a storage medium such as a memory (not shown) together with identification information given to each light source.

  FIG. 15 is a light source coordinate management table for managing the light source and the coordinate information of the pixels constituting the light source. The light source coordinate management table has an item “light source ID” which is identification information given to the light source and an item “coordinate” which is the coordinates of the pixels constituting the light source. Here, it is assumed that “001” to “004” are associated as “area IDs” with the pixels constituting the areas 51a to 54a, respectively.

  Next, the light source selection unit 1022 first receives an electric signal output by the light receiving element in the area in the imaging element 1011 corresponding to the area where the “light source ID” of the captured image is “001”, that is, the area 51a. . For example, when the imaging element 1011 and the captured image have a similar relationship, the light receiving element in the region on the imaging device 1011 that has a similar relationship to the region where the “light source ID” of the captured image is “001” Only the electrical signal output according to the intensity of the received light is continuously received.

  The light source selection unit 1022 separates the frequency of the marker signal, here a signal of 28.8 KHz, from the received electrical signal. Then, the separated signal is sampled at a predetermined sampling period. In this specific example, the relationship between the sampling period and the marker signal is set so that the marker signal can be reliably detected as described with reference to FIG.

  The light source selection unit 1022 ends the reception and sampling of the electrical signal when a predetermined time, for example, 1/10 to 1/30 second, has elapsed from the start of the reception of the electrical signal, and the marker signal is received from the electrical signal. It is determined whether or not it is detected, that is, whether or not the signal separated from the electrical signal at the frequency of the marker signal is a marker signal whose value varies. For example, it is determined whether or not two values “H” and “L” are included in a value obtained by binarizing a plurality of values obtained by sampling with a predetermined threshold value. Here, if binary values are included, the light source selection unit 1022 determines that a marker signal has been detected. Then, the light source selection unit 1022 uses the information indicating the position of the region where the “light source ID” of the captured image is “001”, here the coordinate information of the pixels included in the region 51a as an example, and the position information of the visible light communication light source. And stored in a memory or the like (not shown).

  Next, similarly, an electric signal output by the light receiving element in the area in the image sensor 1011 corresponding to the area where the “light source ID” of the captured image is “002”, that is, the area 52a is received. And the signal of the frequency of a marker signal is isolate | separated from this electric signal, and it samples. Then, similarly to the above, it is determined whether or not the sampled value is a marker signal. Here, it is assumed that the sampled value does not include binary values. The light source selection unit 1022 determines that the marker signal is not detected, and does not acquire the position information of the region where the “light source ID” of the captured image is “002” as the position information of the visible light communication light source.

  Hereinafter, the same processing is performed for the areas with “003” and “004” as the “light source ID”. As a result of these processes, it is assumed that only the coordinate information of the pixels constituting one light source 51 whose “light source ID” is “001” is acquired as the position information of the visible light communication light source.

  FIG. 16 is a visible light communication light source management table for managing position information of visible light communication light sources. The visible light communication light source management table has an item “light source ID” that is identification information of a visible light communication light source and an item “position information” that is coordinate information of each pixel constituting the visible light communication light source. . Here, “light source ID” corresponds to “light source ID” in the light source coordinate management table of FIG. 17, and light sources having the same value are assumed to be the same light source.

  Next, using the position information of the visible light communication light source shown in FIG. 16, the incident position information acquisition unit 1031 is information on the position where light transmitted from the visible light communication light source on the liquid crystal panel 10321 is incident. Acquire communication light incident position information. Here, as an example, it is assumed that the number of pixels of the liquid crystal panel 10321 is 320 × 240 pixels, which is the same as the number of pixels of the captured image, the optical path length until the light passing through the first lens 111 reaches the image sensor 1011, and the first lens It is assumed that the light path length that the light passing through 111 is reflected by the beam splitter 112 and reaches the liquid crystal panel is the same. Then, it is assumed that an image in the same photographing range as the photographed image shown in FIG. 13 is incident on the liquid crystal panel 10321. That is, the coordinate information of the liquid crystal panel 10321 and the coordinate information of the captured image have a one-to-one correspondence. Therefore, the incident position information acquisition unit 1031 acquires the position information of the visible light communication light source as it is as the communication light incident position information. With such a configuration, the process of calculating the communication light incident position information from the position information of the visible light communication light source detected by the light source position detection unit 102 can be omitted, and the processing speed can be increased. Therefore, the communication light incident position information acquired here is the same as that shown in FIG. When the number of pixels of the captured image is different from the number of pixels of the liquid crystal panel 10321, each pixel in the captured image and one or more liquid crystal panels 10321 at positions where the same image as the image indicated by the pixels is projected in advance. A correspondence table showing the correspondence with the pixels may be prepared in a storage medium (not shown), and the communication light incident position information may be acquired from the position information of the visible light communication light source using the correspondence table. . Alternatively, coordinate conversion or the like may be performed.

  Next, the light shielding control unit 10322 controls the liquid crystal panel 10321 so that a region other than the position indicated by the acquired communication light incident position information among the pixels of the liquid crystal panel 10321 is a region that shields light. . Specifically, the liquid crystal panel 10321 is controlled such that only the pixel having the coordinates indicated by the communication light incident position information is a pixel that transmits light. As a result, as shown in FIG. 17, only the position indicated by the communication light incident position information 10321 of the liquid crystal panel becomes the light transmission region 1010. This region is a position where light emitted from the light source 51 that is a visible light communication light source is incident on the liquid crystal panel 10321.

  As a result, as shown in FIG. 18, the liquid crystal panel selectively receives only light emitted from the light source 51 that is a visible light communication light source through the transmission region 1010 that is the region indicated by the communication light incident position information 10321. Is input. The light receiving means 1033 continuously outputs an electrical signal corresponding to the input light.

  Unlike the image sensor 1011, the light receiving unit 1033 such as a photodetector simply outputs an electrical signal corresponding to the intensity of light, and thus can perform high-speed processing. Therefore, information having a higher frequency than that of the image sensor 1011 can be extracted from the electrical signal output by the light receiving unit 1033 according to the incident light.

  Here, if it is set in advance to extract basic information, the information acquisition unit 1034 first extracts the basic information from the electric signal output from the light receiving element 1033 for about 20 milliseconds in order to extract the basic information. A signal of 40 MHz that is a frequency is separated and extracted. Further, the basic information is extracted by demodulating the separated signal. The extracted basic information is temporarily stored in a storage medium (not shown). Here, the basic information acquired by the information acquisition unit 1034 is information indicating a list of program information that can be provided by the server 30 as shown in FIG.

  Next, using the basic information as shown in FIG. 12 acquired by the information acquisition unit 1034, the output unit 104 displays information on a list of programs indicated by the basic information, such as a preview image, on the monitor 1051. A message prompting the user to select a program to view, for example, “Please select a program” is displayed. A display example of the output unit 104 is shown in FIG.

  Next, if the user operates a button or touch panel (not shown) to select a program “News 007”, the terminal transmission target information receiving unit 105 of the optical wireless communication terminal device 10 includes the information acquisition unit 1034. In the acquired basic information as shown in FIG. 12, “S087643” that is an attribute value of “program ID” associated with “news 007” is received. The value of this “program ID” is terminal transmission target information. Then, the terminal transmission target information transmission unit 107 transmits “S087643”, which is the “program ID” received by the terminal transmission target information reception unit 105, using visible light communication using the transmission light source 106. It is assumed that the frequency used at this time is a frequency designated in advance. At this time, since the first lens 111 of the optical wireless communication portable terminal 10a is directed to the ceiling side, the transmission light source 106 is also directed to the ceiling side, and visible light communication light is also emitted toward the ceiling. It becomes.

  When the light receiving means 2011 of the optical wireless communication light source device 20 receives light emitted from the optical wireless communication portable terminal 10a, the information acquisition means 2012 transmits from the optical wireless communication portable terminal 10a from the electrical signal output from the light receiving means 2011. Obtained terminal transmission target information “S087643” is acquired. The reception information transmission unit 203 makes a pair of the terminal transmission target information “S087643” and the identification information of the optical wireless communication light source device 20 stored in advance in the identification information storage unit 202 to the power transmission line to the server 30. Send via. For example, the reception information transmission unit 203 transmits the identification information added to the header of the terminal transmission target information. In this specific example, this identification information is the IP address of the optical wireless communication light source device 20 and is, for example, “192.168.1.31”.

  The server reception unit 304 of the server 30 receives the identification information “LP001” and the terminal transmission target information “S087643” transmitted from the optical wireless communication light source device 20. The server processing unit 305 sends the program information corresponding to the terminal transmission target information “S087643” received by the server receiving unit 304 to the optical wireless communication light source device 20 corresponding to the identification information “192.168.1.31”. An instruction to transmit is given to the server information acquisition unit 302 and the server transmission unit 303.

  In response to this instruction, the server information acquisition unit 302 acquires program information whose “program ID” is “S087643” using the image information management table shown in FIG. 11. This program information is program information whose program name is “News 007”. The server transmission unit 303 sends the program information having the “program ID” acquired by the server information acquisition unit 302 to “S087643” to the optical wireless communication light source device 20 having the IP address “192.168.1.031”. To send. This program information to be transmitted is light source transmission target information.

  The optical wireless communication light source device 20 receives program information transmitted from the server 30 by designating the IP address “192.168.1.31”, that is, light source transmission target information, and receives the received program information by visible light communication. Send. Here, it is assumed that the light source transmission target information transmission unit 206 transmits the program information at 80 MHz. However, the basic information as described above may be transmitted at the same frequency of 40 MHs.

  Since the optical wireless communication portable terminal 10a receives program information in accordance with the operation of the above-described program list, visible light communication is performed from the optical wireless communication light source device 20 by the same operation as that when receiving the basic information. Among the information transmitted in the above, the program information transmitted at a frequency designated in advance as the frequency at which the program information is transmitted, in this case, 80 MHz is acquired.

  The output unit 104 displays “News 007”, which is the received program information, on the display device 1051. FIG. 20 shows a display example of program information “News 007” by the display device 1051.

  The light source position detection unit 102 repeatedly performs the process of acquiring the position information of the visible light communication light source using the second captured images sequentially captured by the image capturing unit 101, and the visible light with respect to the optical wireless communication portable terminal 10a. Even if the relative position of the communication light source changes, the position information of the visible light communication light source is newly acquired at the changed position. Then, communication light incident position information is acquired from the newly acquired position information, and the position of the transmission region of the liquid crystal panel 10321 is adjusted. As a result, it is possible to reliably receive the light output from the visible light communication light source. In particular, in this embodiment, since the position of the transmissive region is adjusted using the liquid crystal panel 10321, no physical operation is necessary, so that the position adjustment can be performed quickly. In addition, mechanical failure is unlikely to occur. Further, even if the shape of the light source is diversified, the transmissive region can be freely changed in accordance with the shape of the light source and the like, so that there is an advantage of high adaptability.

  In the above specific example, when basic information is unnecessary, for example, when the user has a list of programs in advance, transmission and reception of basic information may be omitted. .

  As described above, according to the present embodiment, the position information of the visible light communication light source is acquired from the captured image, and the communication light that is the position information on which the light output from the visible light communication light source is incident using the position information. By acquiring incident position information and acquiring transmission target information that is information transmitted by visible light communication from the visible light communication light source at the position indicated by the communication light incident position information, there is another light source. Transmitted from a single light source that performs visible light communication even when light output from a light source other than the photographed light source, such as light from ambient light, indirect illumination, or the like is incident. Information can be received with high accuracy.

  In this embodiment, a liquid crystal panel 10321 is particularly provided as means for selectively receiving light transmitted from the visible light communication light source. Then, a transmission region is formed in the liquid crystal panel 10321 in accordance with the position of the visible light communication light source, so that light transmitted from the visible light communication light source is selectively received. In such a configuration, the display image of the liquid crystal panel 10321 may be controlled so that the transmission region is formed at a position corresponding to the position where the visible light communication light source is detected in the captured image of the liquid crystal panel 10321. Therefore, calculations such as the direction of the visible light communication light source and the shape and size of the light from the light source are unnecessary. As a result, the processing speed can be increased. In addition, since a physical mechanism for selectively receiving light can be omitted, it is possible to make it difficult for a malfunction to occur due to wear or the like.

  In the present invention, the liquid crystal panel 10321 may be arranged at a position where light having passed through the first lens 111 is incident, and the arrangement is not limited. For example, as in the above-described embodiment, it may be disposed between the beam splitter 112 and the second lens 113, or may be disposed between the second lens 113 and the light receiving means 1033. Further, the liquid crystal panel 10321 may be disposed on the light receiving means 1033. Even when the liquid crystal panel 10321 is arranged at any position, similarly to the above embodiment, areas other than the incident position indicated by the incident position information acquired by the incident position information acquiring means 1031 by the light shielding control means 10322 block light. By controlling the liquid crystal panel 10321 so as to be in the region, the same effect as in the above embodiment can be obtained. In particular, since the liquid crystal panel 10321 is disposed between the second lens 113 and the light receiving means 1033, the transmission of the light converged by the second lens 113 may be controlled. Therefore, the size of the liquid crystal panel 10321 is reduced. Thus, the cost can be reduced.

  In addition, according to the present embodiment, the optical wireless communication terminal device 10 transmits the terminal transmission target information by visible light communication, so that the light source that performs optical wireless communication with the optical wireless communication terminal device 10 is provided. Bidirectional information can be exchanged with the optical wireless communication light source device 20, which is a device provided, for example, interactive information provision can be performed.

  Further, according to the present embodiment, the reception information transmitting unit 203 of the optical wireless communication light source device 20 transmits the terminal transmission target information received by the terminal transmission target information receiving unit 201 in association with the identification information of the own device. By doing so, the server 30 can identify the optical wireless communication light source device 20 that has received the terminal transmission target information, and thereby the optical wireless communication terminal device 10 that has transmitted the terminal transmission target information is located at which optical wireless An optical wireless communication terminal that can determine whether it is in the vicinity of the communication light source device 20, or which optical wireless communication light source device 20 can be used to communicate with the optical wireless terminal device 10, etc. As a result, the device can be specified.

  In the above embodiment, the case where one optical wireless communication light source device 20 transmits information by optical wireless communication and receives information transmitted by optical wireless communication has been described. The optical wireless communication light source device may be realized by a plurality of devices as long as the optical wireless communication light source device can perform substantially the same processing as described above. You may implement | achieve by the combination with the apparatus which receives the information transmitted by radio | wireless communication.

  In addition, as described above, the optical wireless communication system of the present invention can be applied to optical wireless communication that can use light other than visible light, for example, infrared rays and ultraviolet rays. Also, the same effects as those of the above embodiment can be obtained. The optical wireless communication described here refers to communication using light waves having a very high frequency compared to radio waves, such as visible light, infrared light, and ultraviolet light.

  In the above embodiment, each processing (each function) may be realized by centralized processing by a single device (system), or may be realized by distributed processing by a plurality of devices. May be.

  In the above embodiment, two or more communication means (the reception information transmission unit 203 and the light source transmission target information reception unit 204, etc.) existing in one device may be physically realized by one medium. Needless to say.

  In the above embodiment, information related to processing executed by each component, for example, information received, acquired, selected, generated, transmitted, and received by each component. In addition, information such as threshold values, mathematical formulas, addresses, etc. used by each component in processing is retained temporarily or over a long period of time on a recording medium (not shown) even when not explicitly stated in the above description. It may be. Further, the storage of information in the recording medium (not shown) may be performed by each component or a storage unit (not shown). Further, reading of information from the recording medium (not shown) may be performed by each component or a reading unit (not shown).

  In each of the above embodiments, each component may be configured by dedicated hardware, or a component that can be realized by software may be realized by executing a program. For example, each component can be realized by a program execution unit such as a CPU reading and executing a software program recorded on a recording medium such as a hard disk or a semiconductor memory.

  In addition, the software which implement | achieves the optical wireless communication terminal device in each said embodiment is the following programs. In other words, this program causes a computer to capture one or more light sources including an optical wireless communication light source that is a light source that performs optical wireless communication, and to acquire an image, and a captured image that is an image acquired by the imaging unit A light source position detection unit that detects an optical wireless communication light source and acquires position information that is information on a position of the optical wireless communication light source, and a position information of the optical wireless communication light source acquired by the light source position detection unit. Information transmitted from the optical wireless communication light source by optical wireless communication at the position indicated by the communication light incident position information is obtained by acquiring communication light incident position information that is information on a position where light output from the wireless communication light source is incident. An information acquisition unit that acquires light source transmission target information, an output unit that outputs information acquired by the information acquisition unit, and a terminal transmission that receives terminal transmission target information that is information to be transmitted A target information receiving unit, a program for functioning as the terminal transmission target information transmitting unit that transmits the light at the terminal transmission target information from the transmission source is for performing optical radio communication by optical wireless communication.

  In the above program, in a transmission step for transmitting information, a reception step for receiving information, etc., processing performed by hardware, for example, processing performed by a modem or an interface card in the transmission step (only performed by hardware). Not included) is not included.

  In the program, the functions realized by the program do not include functions that can be realized only by hardware. For example, a function that can be realized only by hardware such as a modem or an interface card in an acquisition unit that acquires information or an output unit that outputs information is not included in the function realized by the program.

  Further, the computer that executes this program may be singular or plural. That is, centralized processing may be performed, or distributed processing may be performed.

  FIG. 21 is a schematic diagram illustrating an example of an external appearance of a computer that executes the program and realizes the optical wireless communication terminal device and the like according to the embodiment. The above-described embodiment can be realized by computer hardware and a computer program executed on the computer hardware.

  21, a computer system 900 includes a computer 901 including a CD-ROM (Compact Disk Read Only Memory) drive 905 and an FD (Floppy (registered trademark) Disk) drive 906, a keyboard 902, a mouse 903, a monitor 904, and the like. Is provided.

  FIG. 22 is a diagram showing an internal configuration of the computer system 900. In FIG. 22, in addition to the CD-ROM drive 905 and the FD drive 906, a computer 901 is connected to an MPU (Micro Processing Unit) 911, a ROM 912 for storing a program such as a bootup program, and the MPU 911. A RAM (Random Access Memory) 913 that temporarily stores program instructions and provides a temporary storage space, a hard disk 914 that stores application programs, system programs, and data, and an MPU 911 and a ROM 912 are interconnected. And a bus 915. The computer 901 may include a network card (not shown) that provides connection to the LAN.

  A program that causes the computer system 900 to execute the functions of the optical wireless communication terminal device and the like according to the above-described embodiment is stored in the CD-ROM 921 or FD 922, inserted into the CD-ROM drive 905 or FD drive 906, and the hard disk 914 may be forwarded. Instead, the program may be transmitted to the computer 901 via a network (not shown) and stored in the hard disk 914. The program is loaded into the RAM 913 when executed. The program may be loaded directly from the CD-ROM 921, the FD 922, or the network.

  The program does not necessarily include an operating system (OS) or a third party program that causes the computer 901 to execute the functions of the optical wireless communication terminal device according to the above-described embodiment. The program may include only a part of an instruction that calls an appropriate function (module) in a controlled manner and obtains a desired result. How the computer system 900 operates is well known and will not be described in detail.

  The present invention is not limited to the above-described embodiments, and various modifications are possible, and it goes without saying that these are also included in the scope of the present invention.

  As described above, the optical wireless communication terminal device according to the present invention is suitable as a device that performs communication by optical wireless communication, and is particularly useful as a device that performs communication by visible light communication.

DESCRIPTION OF SYMBOLS 1 Optical wireless communication system 10 Optical wireless communication terminal device 10a Optical wireless communication portable terminal 20 Optical wireless communication light source device 30 Server 101 Image pick-up part 102 Light source position detection part 103 Information acquisition part 104 Output part 105 Terminal transmission object information reception part 106 For transmission Light source 107 Terminal transmission target information transmission unit 111 First lens 112 Beam splitter 113 Second lens 201 Terminal transmission target information reception unit 202 Identification information storage unit 203 Reception information transmission unit 204 Light source transmission target information reception unit 205 Visible light communication light source 206 Light source Transmission target information transmission unit 301 Server storage unit 302 Server information acquisition unit 303 Server transmission unit 304 Server reception unit 305 Server processing unit 1011 Imaging element 1012 Image processing unit 1021 Light source detection unit 1022 Light source selection unit 1031 Incident position information acquisition unit 1032 Selective transmission means 1033 Light receiving element 1033, 2011 Light receiving means 1034, 2012 Information acquisition means 1051 Display device 2062 Marker signal output means 2063 Superimposition means 1071, 2061 Modulation means 1072, 2064 Transmission means 10321 Liquid crystal panel 10322 Light shielding control means

Claims (5)

A photographing unit that photographs one or more light sources including an optical wireless communication light source that is a light source that performs optical wireless communication;
A light source position detection unit that detects an optical wireless communication light source in a captured image that is an image acquired by the imaging unit, and acquires position information that is information on a position of the optical wireless communication light source;
From the position information of the optical wireless communication light source acquired by the light source position detection unit, communication light incident position information, which is information on a position where light output from the optical wireless communication light source is incident, is acquired, and the communication light incident position information An information acquisition unit that acquires light source transmission target information that is information transmitted by optical wireless communication from the optical wireless communication light source at the position indicated by:
An output unit for outputting the information acquired by the information acquisition unit;
A terminal transmission target information receiving unit that receives terminal transmission target information that is information to be transmitted;
A light source for transmission for transmitting the terminal transmission target information;
An optical wireless communication terminal apparatus comprising: a terminal transmission target information transmitting unit configured to transmit the terminal transmission target information from the transmission light source by optical wireless communication. An optical wireless communication system comprising: an optical wireless communication terminal device; and an optical wireless communication light source device having one or more optical wireless communication light sources that are light sources for performing optical wireless communication,
The optical wireless communication terminal device
A photographing unit that photographs one or more light sources including an optical wireless communication light source included in the optical wireless communication light source device;
A light source position detection unit that detects an optical wireless communication light source in a captured image that is an image acquired by the imaging unit, and acquires position information that is information on a position of the optical wireless communication light source;
From the position information of the optical wireless communication light source acquired by the light source position detection unit, communication light incident position information, which is information on a position where light output from the optical wireless communication light source is incident, is acquired, and the communication light incident position information An information acquisition unit that acquires light source transmission target information that is information transmitted by optical wireless communication from an optical wireless communication light source that is a light source included in the optical wireless communication light source device;
An output unit for outputting the information acquired by the information acquisition unit;
A terminal transmission target information receiving unit that receives terminal transmission target information that is information to be transmitted;
A transmission light source for transmitting terminal transmission target information;
A terminal transmission target information transmitting unit that transmits the terminal transmission target information from the transmission light source by optical wireless communication;
The optical wireless communication light source device is:
A terminal transmission target information receiving unit for receiving terminal transmission target information transmitted by optical wireless communication from the optical wireless communication terminal device;
A reception information transmitting unit for transmitting the terminal transmission target information received by the terminal transmission target information receiving unit;
A light source transmission target information receiving unit that receives light source transmission target information that is information to be transmitted to the optical wireless communication terminal device;
One or more optical wireless communication light sources which are light sources for performing optical wireless communication for transmitting the light source transmission target information;
An optical wireless communication system comprising: a light source transmission target information transmitting unit configured to transmit the light source transmission target information received by the light source transmission target information receiving unit from the optical wireless communication light source by optical wireless communication. The optical wireless communication light source device is:
An identification information storage unit that can store identification information that is information for identifying the device itself;
The optical wireless communication system according to claim 2, wherein the reception information transmitting unit transmits the terminal transmission target information received by the terminal transmission target information receiving unit in association with the identification information of the own device. An imaging unit, a light source position detection unit, an information acquisition unit, an output unit, a terminal transmission target information reception unit, a transmission light source that is a light source for performing optical wireless communication, and a terminal transmission target information transmission unit An optical wireless communication method performed using:
A photographing step in which the photographing unit photographs one or more light sources including an optical wireless communication light source that is a light source that performs optical wireless communication;
A light source position detecting unit that detects an optical wireless communication light source in a captured image that is an image acquired in the imaging step, and acquires position information that is position information of the optical wireless communication light source; and
The information acquisition unit acquires communication light incident position information, which is information of a position where light output from the optical wireless communication light source is incident, from the position information of the optical wireless communication light source acquired in the light source position detection step, An information acquisition step of acquiring light source transmission target information that is information transmitted by optical wireless communication from the optical wireless communication light source at the position indicated by the communication light incident position information;
An output step in which the output unit outputs the information acquired in the information acquisition step;
A terminal transmission target information receiving step in which the terminal transmission target information receiving unit receives terminal transmission target information which is information to be transmitted;
An optical wireless communication method comprising: a terminal transmission target information transmitting step in which the terminal transmission target information transmission unit transmits the terminal transmission target information from the transmission light source by optical wireless communication. Computer
A photographing unit that photographs one or more light sources including an optical wireless communication light source that is a light source that performs optical wireless communication;
A light source position detection unit that detects an optical wireless communication light source in a captured image that is an image acquired by the imaging unit, and acquires position information that is information on a position of the optical wireless communication light source;
From the position information of the optical wireless communication light source acquired by the light source position detection unit, communication light incident position information, which is information on a position where light output from the optical wireless communication light source is incident, is acquired, and the communication light incident position information An information acquisition unit that acquires light source transmission target information that is information transmitted by optical wireless communication from the optical wireless communication light source at the position indicated by:
An output unit for outputting the information acquired by the information acquisition unit;
A terminal transmission target information receiving unit that receives terminal transmission target information that is information to be transmitted;
The program for functioning as a terminal transmission object information transmission part which transmits the said terminal transmission object information by optical wireless communication from the light source for transmission which is a light source for performing optical wireless communication.

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