JP2014067177A - Information code reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily achieve a configuration for enhancing the sealing property of a case and effectively removing the blur of a plate disposed in a light reception path.SOLUTION: An information code reader 1 includes a case 2 which includes a reading port 2a, an imaging part 3 which is stored in the case 2 and can image an information code C outside the case 2 through the reading port 2a, a light-transmitting plate 5 which is arranged between the reading port 2a and the imaging part 3 and seals the opening of the case 2, a substrate 10 on which an antenna 11 is mounted and which is arranged close to and opposite to the plate 5, a heating element 12 which is arranged as a part of the antenna 11 or in such a configuration that the heating element 12 is electrically connected to the antenna 11, in the substrate 10 and generates heat, during energization to the antenna 11, and a current-carrying part which flows an electric current to the antenna 11, to generate the heat in the heating element 12, when a predetermined energization condition is established.

Description

  The present invention relates to an information code reader.

  Conventionally, information code readers for reading barcodes and two-dimensional codes have been widely provided. This type of information code reader generally captures an information code outside the case through a reading port formed in the terminal, and reads the content recorded in the information code by analyzing the captured image. . As another type of information processing terminal, there is also a non-contact communication terminal as disclosed in Patent Document 1, and in recent years, a terminal having these functions is also provided.

JP 2007-104092 A

  By the way, in the information code reader, a transparent plate is often provided so as to block the vicinity of the reading port for dust prevention or the like. In this case, the imaging unit arranged in the case is arranged near the reading port. The information code outside the case is imaged by receiving the light passing through the plate. According to this configuration, the information code outside the case can be imaged and read while enhancing the sealing of the case.

  However, in this configuration, it is inevitable that the captured image becomes unclear when the plate is clouded. When the information code is imaged and read in such a state that the plate is clouded, each module is read. May not be accurately recognized and may become unreadable. In particular, the information code reader is often used in a humid place such as outdoors, and various cases are expected to cause the above problem. Therefore, a configuration that can effectively solve the above problem is strongly demanded. . However, if a large-scale configuration is adopted to remove fogging, the device configuration is increased in size and weight, so it is desirable to solve the above problem with a simpler and lighter configuration.

  The present invention has been made to solve the above-described problem, and in an information code reader having both a function of reading an information code and a function of reading a non-contact communication medium, the sealing performance of the case can be improved. It is another object of the present invention to more easily realize a configuration that can effectively remove fogging of a plate disposed in a light receiving path.

The present invention has been made to solve the above-described problems,
A case with a reading port;
An imaging unit that is housed inside the case and can image an information code outside the case through the reading port;
A light transmissive plate disposed between the reading port and the imaging unit and closing the opening of the case;
A decoding unit for decoding the information code based on the captured image obtained by the imaging unit;
A substrate on which an antenna is mounted and which is disposed oppositely in the vicinity of the plate;
A heating element that is arranged as a part of the antenna or electrically connected to the antenna on the substrate, and generates heat when the antenna is energized,
A communication unit that transmits and receives electromagnetic waves via the antenna and communicates with a non-contact communication medium through the electromagnetic waves;
A current-carrying part that causes a current to flow to the antenna when a predetermined energization condition is satisfied, and heats the heating element;
It is characterized by having.

  According to the first aspect of the present invention, in the information code reader having both the function of reading the information code and the function of reading the non-contact communication medium, the imaging unit is housed inside the case and transparent to close the case opening. Since the plate is placed between the reading port and the imaging unit, it enhances the sealing of the case to prevent dust, etc., and receives the light entering through the plate and images the information code outside the case. It becomes possible to read. In such a configuration, since the heating element is provided as a part of the antenna or electrically connected to the antenna, a current flows through the heating element near the antenna even when the plate is fogged. Thus, the heat generating element can generate heat, and this heat can be transmitted to adjacent plates. Then, the fog generated on the plate is effectively removed by this heat. In addition, since the heating element is arranged on the substrate as a part of the antenna or electrically connected to the antenna, the heating element can be heated using the energization path of the antenna without providing a special energization path. Is possible. Accordingly, it is easy to simplify the device configuration, reduce the number of parts, and reduce the weight of the device as compared with a configuration in which independent current-carrying portions are provided.

  In the invention of claim 2, the substrate or the component fixed to the substrate is arranged in contact with the inner surface of the plate. According to this configuration, when the heat generating element generates heat, heat can be more reliably transmitted to the plate from the substrate on which the antenna is mounted or a component on the substrate, and the fog generated on the plate can be better removed. it can.

  According to a third aspect of the present invention, an opening is formed in the substrate, the imaging unit is configured to be able to image the information code through the opening, the heating element is made of a resistance element, and the antenna has a resistance element having an opening. In an annular form arranged continuously in a configuration that at least partially surrounds. If the resistance elements are continuously arranged in such a configuration surrounding the opening, heat from the heating element is easily transmitted uniformly to the portion near the opening in the plate, and near the center of the plate where the heating element is difficult to face ( Heat is easily transmitted to the portion corresponding to the opening region. As a result, it is possible to more effectively remove the haze in the vicinity of the center as well as the vicinity of the opening in the plate.

  In the invention of claim 4, an opening is formed in the substrate, the imaging unit is configured to be able to image the information code through the opening, the heating element is composed of a resistance element, and the antenna is composed of a plurality of resistance elements. They are connected in series at intervals, and are arranged in a ring shape in a configuration surrounding the opening. If a plurality of resistance elements are connected in series at such an interval, the heat generation part can be dispersed over a wide range while suppressing the resistance value, and the heat from the heat generation element is uniformly transmitted to the part near the opening in the plate. It becomes easy. Further, heat is easily transferred to the vicinity of the central portion of the plate where the heating elements are difficult to face each other (the portion corresponding to the opening region), and the clouding around the central portion as well as the opening portion of the plate is more effectively removed. be able to.

  According to the invention of claim 5, a temperature sensor is provided inside or outside the case, and the energization section generates a heat by flowing a current to the antenna on condition that the temperature detected by the temperature sensor reaches a predetermined temperature. The device is configured to generate heat. According to such a configuration, the plate can be heated when the temperature near the case reaches a predetermined temperature and clouding is likely to occur, and the clouding can be efficiently removed in an environment where clouding is likely to occur. Can do.

  In the invention of claim 6, a temperature sensor capable of detecting the temperature inside and outside the case is provided, and the energization section is provided on the condition that the temperature difference between the inside and outside of the case detected by the temperature sensor reaches a predetermined value. A current is passed through the antenna to generate heat from the heating element. According to such a configuration, the plate can be warmed when the temperature difference between the inside and outside of the case reaches a predetermined value and clouding is likely to occur, and the situation where clouding is likely to occur can be grasped more accurately and efficiently. The fog can be removed.

  In a seventh aspect of the present invention, the energization section is configured to cause a current to flow through the antenna and heat the heating element on condition that a suspension time of energization to the antenna reaches a certain time. According to such a configuration, it is possible to periodically remove heat by causing the heat generating element to generate heat, and it is easy to maintain a state in which fog does not occur.

  The invention of claim 8 further includes a fog detection unit that detects the degree of fogging of the plate based on an image outside the plate obtained by the imaging unit, and the antenna is provided on the condition that a predetermined fog detection result is obtained by the fog detection unit. In this configuration, current is supplied to the heater element to generate heat. According to such a configuration, since the imaging unit can be used for clouding detection, the configuration of the apparatus can be simplified as compared with a configuration in which clouding detection is performed using only dedicated components. Further, since the image outside the plate reflects the state of light obtained through the plate, it is easy to accurately grasp the actual degree of fogging of the plate.

According to a ninth aspect of the present invention, there is provided a case provided with a reading port, an imaging unit that is housed in the case and can image an information code outside the case through the reading port, and between the reading port and the imaging unit. A light-transmitting plate that closes the opening of the case, a decoding unit that decodes the information code based on the captured image obtained by the imaging unit, an antenna, and an antenna that is placed close to each other A substrate that transmits and receives electromagnetic waves via an antenna, and a communication unit that communicates with a non-contact communication medium using the electromagnetic wave as a medium, and clouding that detects the degree of cloudiness of the plate based on an image outside the plate obtained by the imaging unit It has a configuration including a detection unit and a heating unit that generates heat on the condition that a predetermined clouding detection result is obtained by the clouding detection unit.
In this configuration, in the information code reading apparatus having both the function of reading the information code and the function of reading the non-contact communication medium, the imaging unit is housed in the case and the transparent plate that closes the opening of the case is read. Because it is arranged between the mouth and the imaging unit, it is possible to capture and read the information code outside the case by receiving light entering through the plate while improving the sealing of the case for dust prevention etc. Become. In such a configuration, the imaging unit can also be used for clouding detection, so that the configuration of the apparatus can be simplified as compared with a configuration in which clouding detection is performed using only dedicated components. Further, since the image outside the plate reflects the state of light obtained through the plate, it is easy to accurately grasp the actual degree of fogging of the plate.

  According to the invention of claim 10, a design portion formed of a predetermined shape, pattern, color, or combination thereof is formed as a part of the case or a portion fixed to the case at a position facing the plate outside the plate. The imaging unit is configured to be able to image the design part via the plate, and the fog detection unit is configured to detect the degree of fogging of the plate based on the imaging result of the design part by the imaging unit. Yes. According to such a configuration, it is possible to accurately determine how the image of the design portion is changed according to the degree of fogging, with the design portion as a reference portion, and consequently, the degree of cloudiness of the plate can be accurately determined. Can be detected.

  In the invention of claim 11, the design portion is formed with a light and dark pattern including a light color pattern and a dark color pattern on the plate side, and the cloudiness detection portion is a cloudiness of the plate based on the imaged result of the light and dark pattern by the imaging portion. It is the structure which detects a degree. In this configuration, when the degree of cloudiness on the plate changes, the relationship between the brightness of the image obtained from the light color pattern and the brightness of the image obtained from the dark color pattern (for example, the brightness difference) changes greatly. By doing so, it becomes easy to grasp the cloudiness degree with high accuracy.

FIG. 1 is a sectional view schematically showing an information code reading apparatus according to the first embodiment of the present invention. FIG. 2 is a block diagram schematically illustrating an electrical configuration of the information code reader according to the first embodiment of the present invention. FIG. 3 is a plan view schematically illustrating an antenna, a substrate, and the like used in the information code reader of FIG. FIG. 4 is an explanatory diagram for explaining a state in which the substrate side is viewed from the imaging unit side in the information code reader of FIG. FIG. 5 is an explanatory diagram for explaining an image signal generated based on an imaging result when a specific part near the opening is imaged by the imaging unit in the information code reading apparatus of FIG. 1. FIG. 5 is a diagram for explaining an image signal in a state where fog is not generated, and FIG. 5B is a diagram for explaining an image signal when fog is generated. FIG. 6 is a flowchart illustrating the flow of the defogging process. FIG. 7 is a plan view schematically illustrating an antenna, a substrate, and the like used in the information code reader according to the second embodiment of the present invention.

[First embodiment]
Hereinafter, a first embodiment embodying the present invention will be described with reference to the drawings.
The information code reader 1 according to the first embodiment is configured as, for example, a stationary information communication terminal, and functions as an information code reader that reads an information code C such as a barcode or a two-dimensional code, and non-contact communication. It has a function as a non-contact reader that reads a medium T (an IC card or other wireless tag capable of non-contact communication), and is configured to be able to read in two ways.

(overall structure)
As shown in FIG. 1, the information code reading device 1 includes a case 2 in which a CCD sensor (imaging unit) 3, a substrate 10, and a plate 5 are accommodated. A reading port 2a for conducting light is formed. The case 2 has, for example, a box shape configured in a square shape or a rectangular shape in plan view, and in the example of FIG. 1, the reading port 2a is provided in a form in which one side is open. In the present embodiment, in the case 2 configured in a box shape, the side on which the reading port 2a is provided is the upper side, and the opposite side is the lower side.

  The CCD sensor 3 corresponds to an example of an imaging unit, and is arranged in a configuration in which a light receiving unit is provided on the upper surface. The CCD sensor 3 is disposed inside the case 2 so as to face the reading port 2a, and can capture an information code C outside the case 2 through the reading port 2a and an opening 10a of the substrate 10 described later. It is arranged in. That is, when the information code C is arranged toward the reading port 2a, the reflected light from the information code C is received by the CCD sensor 3 through the reading port 2a and the opening 10a. Although not shown, a lens for condensing light entering from outside the case is arranged. This lens has an optical axis in the vertical direction, and condenses the reflected light from the information code C to collect the CCD. The image is formed on the light receiving surface of the sensor 3. In the example of FIG. 1, the range (light reception viewing angle) that can be imaged by the CCD sensor 3 via the lens is indicated by θ. Further, the imageable range outside the case 2 is indicated by AR. Further, the center (light receiving optical axis) of the light receiving range of the light receiving system constituted by the lens and the CCD sensor 3 is indicated by the symbol G, and the light receiving optical axis G is set to be in the vertical direction.

  The substrate 10 is configured in a plate shape with the vertical direction as the thickness direction, and is mounted with an antenna 11 (to be described later) and opposed to the plate 5 in close proximity. Specifically, the upper surface of the substrate 10 or a component fixed to the upper surface of the substrate 10 is arranged in contact with the inner surface (lower surface) of the plate 5. 1 shows an example in which the antenna 11 is directly fixed to the lower surface of the substrate 10. However, if the antenna 11 is configured to be fixed to the lower surface of the substrate 10, the antenna 11 is indirectly connected via another member. May be fixed. Further, the substrate 10 is provided with an opening 10a that penetrates in the vertical direction and opens in an opening range slightly wider than the opening range of the reading port 2a of the case 2. The opening 10a has a rectangular shape when viewed in plan, for example.

  The plate 5 is configured as a light-transmitting (specifically, transparent) plate made of, for example, a resin material or a glass material, and is disposed between the reading port 2a of the case 2 and the CCD sensor 3, and from the reading port 2a. It is arranged slightly below and is configured to close the opening on one side (upper side) of the case 2.

  As shown in FIG. 2, the information code reader 1 includes a control circuit 20 that performs overall control. The control circuit 20 includes a communication processing unit 30, a temperature detection circuit 52, a reading processing unit 40, and an illumination LED 44. Is connected. In addition, the information code reader 1 includes a circuit board 60 on which various electronic components are mounted. The circuit board 60 is configured as a board different from the board 10 on which the antenna 11 is mounted. In the example of FIG. 1, the CCD sensor 3 is mounted on the circuit board 60.

  The control circuit 20 is composed mainly of a microcomputer, has a CPU, a system bus, an input / output interface, and the like, and functions as an information processing apparatus. The communication processing unit 30, the temperature detection circuit 52, the reading processing unit 40, and the illumination LED 44 are all configured to be controlled or acquired by the control circuit 20.

  As illustrated in FIG. 1, the reading processing unit 40 includes an AD conversion circuit 41 and a decoding processing unit 42, and reads an information code attached to an object to be read in cooperation with the control circuit 20. To function. In the example of FIG. 2, QR code (registered trademark) C is exemplified as the information code. However, other two-dimensional codes such as a data matrix code may be used, and a known one-dimensional code such as a barcode may be used. It may be.

When reading is performed by the reading processing unit 40, first, illumination light is emitted from the illumination LED 44 that has received a command from the control circuit 20, and this illumination light passes through the reading port 2a (see FIG. 1) and is to be read (illustrated). (Omitted). The reflected light of the illumination light reflected by the information code C is taken into the apparatus through the reading port 2a, and is received by the CCD sensor 3 through an imaging lens (not shown). An imaging lens (not shown) arranged between the reading port 2a and the CCD sensor 3 is configured to form an image of the information code C on the CCD sensor 3. The CCD sensor 3 outputs a light reception signal corresponding to the image of the information code C. The received light signal output from the CCD sensor 3 is converted from an analog signal to a digital signal by the AD conversion circuit 41, and further decoded by the decode processing unit 42.
In the present embodiment, the CCD sensor 3 corresponds to an example of an “imaging unit”, and is accommodated inside the case 2 and functions to image the information code C outside the case via the reading port 2a. The reading processing unit 40 and the control circuit 20 correspond to an example of a “decoding unit”, and function to decode the information code C based on the captured image obtained by the CCD sensor 3.

The communication processing unit 30 cooperates with the antenna 11 and the control circuit 20 to perform electromagnetic wave communication with the non-contact communication medium T, read data stored in the non-contact communication medium T, or non-contact communication medium. It functions to write data to T.
In the present embodiment, the communication processing unit 30 and the control circuit 20 correspond to an example of a “communication unit”, which transmits and receives electromagnetic waves via the antenna 11 and performs wireless communication with the non-contact communication medium T through the electromagnetic waves. To function.

  The communication processing unit 30 is configured, for example, as a circuit that performs transmission using a known radio wave method, and includes a transmission circuit 32, a modulation circuit 31, a reception circuit 33, a demodulation circuit 34, and the like as illustrated in FIG. . Among these, the control circuit 20 includes a carrier oscillator, an encoding unit, and the like, and is configured to output a carrier (carrier wave) having a frequency of 953 MHz, for example, from the carrier oscillator. The encoding unit is configured to encode transmission data stored in the control circuit 20 and output it to the modulation circuit 31.

  The modulation circuit 31 receives a carrier (carrier wave) from the carrier oscillator and transmission data from the encoding unit, and transmits a command to the communication target with respect to the carrier (carrier wave) output from the carrier oscillator. A modulated signal that is ASK (Amplitude Shift Keying) modulated by the encoded transmission code (modulated signal) output from the encoding unit is generated and output to the transmission circuit 32. The transmission circuit 32 includes an amplifier, a transmission unit filter, and the like. The amplifier amplifies an input signal (a modulated signal modulated by the modulation unit) with a predetermined gain, and the amplified signal is transmitted to the transmission unit filter. The transmitter filter outputs a transmission signal obtained by filtering the amplified signal from the amplifier to the antenna 11. When a transmission signal is output to the antenna 11 in this way, the transmission signal is radiated to the outside from the antenna 11 as an electromagnetic wave.

  On the other hand, a radio signal received by the antenna 11 (radio signal from the non-contact communication medium T) is input to the receiving circuit 33. The reception circuit 33 is configured by a reception unit filter, an amplifier, and the like. The signal received via the antenna 11 is filtered by the reception unit filter, then amplified by the amplifier, and the amplified signal is output to the demodulation circuit 34. To do. The demodulation circuit 34 includes a demodulation unit, a binarization processing unit, a decoding unit, and the like. When an amplified signal is input, the demodulation unit demodulates the amplified signal. Then, the demodulated signal waveform is binarized by the binarization processing unit and decoded by the decoding unit, and then the decoded signal is output to the control circuit 20 as reception data.

  The non-contact communication medium T is configured as a known non-contact IC card or other types of RFID tags in terms of hardware, and includes, for example, an antenna, a power supply circuit, a demodulation circuit, a control circuit, a memory, a modulation circuit, and the like. ing. Here, the power supply circuit rectifies and smoothes a transmission signal (carrier signal) from a communication terminal received via an antenna to generate an operation power supply. The operation power supply includes a control circuit and the like. Supply to each component. The demodulating circuit demodulates data superimposed on the transmission signal (carrier signal) and outputs the demodulated data to the control circuit. The memory is composed of various semiconductor memories such as ROM and EEPROM. For example, tag identification information (tag ID) for identifying a control program and an RFID tag, data set by a user according to the use of the RFID tag ( Merchandise data, logistics data, etc.) are stored. The control circuit is configured to read the above information and data from the memory and output it to the modulation circuit as transmission data. The modulation circuit load modulates the carrier signal with the transmission data and transmits it as a reflected wave from the antenna. Is configured to do.

  A temperature detection element 50 (temperature sensor (eg, a thermistor)) is connected to the temperature detection circuit 52, and the detection result of the input temperature detection element 50 is output to the control circuit 20 as a temperature signal. ing. The temperature detection element 50 is provided inside the case 2 or outside the case 2 (in the example of FIG. 3, an example disposed on the substrate 10 is illustrated), and the temperature at the installation position of the temperature detection element 50 is determined. Configured to detect.

(Characteristic configuration)
As shown in FIG. 3, the substrate 10 includes an antenna 11, a coil 13, a capacitor 14, a connector 15, and a temperature detection element 50. The antenna 11 includes a resistance element 12a made of a known thin film resistor or thick film resistor (the resistance element 12a corresponds to an example of a heating element or a heating part) and a wiring part 12b made of metal wiring. Are arranged in a ring shape so as to surround the opening 10a of the substrate 10 (for example, a configuration such as a loop antenna). The resistance element 12a is configured as a part of the antenna 11, and is configured to generate heat when a current flows when the antenna 11 is energized.

  More specifically, a plurality of resistance elements 12a are arranged in a ring around the opening 10a at intervals, and each wiring portion 12b is provided so as to conduct between the resistance elements. . As described above, the antenna 11 is configured by the configuration in which the plurality of resistance elements 12a and the wiring portion 12b are connected in series. In the example of FIG. 3, both the resistance element 12a and the wiring portion 12b are configured as a pattern formed on the substrate surface. However, the resistance antenna 12a and the wiring portion 12b may form a loop antenna. It is not limited to this example. In addition, a coil 13 is connected to the antenna 11 in series, and an antenna current is supplied from the transmission circuit 32 via the coil 13. In the example of FIG. 3, a connector 15 for connecting the wiring of the transmission circuit 32 and the antenna 11 is provided on the substrate 10, and the connector 15 includes one end portion and the other end portion of the antenna 11. Are connected to each other, and a capacitor 14 is connected between the integrated portion and the other end portion. Further, the temperature detection element 50 is also provided on the substrate 10 and connected to the temperature detection circuit 52 (FIG. 2) via the connector 15.

  As shown in FIG. 4, when the information code reading device 1 is viewed from the CCD sensor 3 side (that is, the lower side) from the substrate 10 side, the information code reading device 1 is located at a position facing the plate 5 outside the plate 5 (reading port 2 a side). The design part 7 which consists of predetermined | prescribed shape, a pattern, a color, or these combination is formed as a part fixed to the case 2 as a part of the case 2. FIG. In the example of FIGS. 1 and 4, the design portion 7 is configured to show a light and dark pattern including a light color pattern and a dark color pattern, and faces the plate 5 as a part of the inner wall of the case 2 (lower surface side). Is formed. In the example of FIG. 4, the dark color pattern 7 a constituting the design portion 7 is arranged in an annular manner at intervals so as to follow the inner edge of the opening 10 a when viewed from the lower side. A portion 7b composed of a bright color is disposed between the two. That is, in this configuration, when viewed from the lower side, the light color pattern and the dark color pattern are alternately arranged in the vicinity of the opening 10a.

  Then, the CCD sensor 3 images the design portion 7 via the plate 5, and the clouding detection unit described later detects the degree of cloudiness of the plate 5 based on the imaging result of the design portion 7 (light / dark pattern) by the CCD sensor 3. Is configured to do. The captured image of the CCD sensor 3 is not only an image captured through the reading port 2a as shown by a one-dot chain line A2 in FIG. 4, for example, but also a specific part (specifically, near the opening 10a on the case inner wall side) In addition, an image of the design portion 7 and its vicinity) is always included. In the image of the design portion 7, the luminance value of the specific line A2 is converted into a waveform as shown in FIG. A waveform can be obtained.

(Defrosting process)
Next, the fogging detection process of the plate 5 in the information code reading apparatus 1 configured as described above will be described with reference to the flowchart shown in FIG.
First, in step S1, the temperature of the installation position of the temperature detection element 50 is detected based on the signal from the temperature detection element 50. In the example of FIG. 1, for example, a temperature detection element 50 is disposed in proximity to the plate 5 with the substrate 10 interposed therebetween, so that the temperature in the vicinity of the plate 5 on the substrate 10 can be measured. Then, it is determined whether or not the temperature of the temperature detecting element 50 is equal to or higher than a predetermined temperature. Here, the predetermined temperature is, for example, a temperature at which the plate 5 is expected to be fogged, and in this apparatus, data (threshold data) specifying the predetermined temperature is stored in a storage unit (not shown). If the detected temperature detected by the temperature detecting element 50 is lower than a predetermined temperature set in advance, the process proceeds to No in S1, and the defogging process is terminated. On the other hand, if the temperature detected by the temperature detection element 50 is equal to or higher than the predetermined temperature, the process proceeds to Yes in S1. Note that the defogging process shown in FIG. 6 is performed every predetermined short time (for example, every several milliseconds, every few seconds, or every few minutes). That is, in the example of FIG. 6, the temperature in the vicinity of the plate 5 is detected every predetermined short time, and when the temperature is equal to or higher than the predetermined temperature, a specific cloudiness determination is performed assuming that the possibility of cloudiness is high. In this configuration, “the temperature detected by the temperature detection element 50 is equal to or higher than a predetermined temperature” is one of the energization conditions.

  When the process proceeds to Yes in S <b> 1, in S <b> 2, the CCD sensor 3 captures an image including the design portion 7 through the plate 5. As described above, in the CCD sensor 3, the area indicated by reference numeral A1 in FIG. 4 is always an imageable range. In S2, the image of the design portion 7 is obtained by capturing an image in such an area A1. To get.

In S <b> 3, the fogging degree of the plate 5 is analyzed based on the imaging result of the design portion 7 (image outside the plate 5) by the CCD sensor 3. In addition, since the image outside the plate 5 reflects the state of light obtained through the plate 5, it is easy to grasp the actual degree of cloudiness of the plate 5. Further, when the degree of fogging of the plate 5 changes, the relationship between the brightness of the image obtained from the bright color pattern of the design portion 7 and the brightness of the image obtained from the dark color pattern (for example, a brightness difference) greatly changes. If the luminance waveform is analyzed, the degree of cloudiness can be accurately grasped. Therefore, first, in S3, the luminance waveform of the design unit 7 is acquired. Specifically, as indicated by reference numeral A2 in FIG. 4, lines that alternately cross the dark color pattern 7a and the light color pattern 7b of the design portion 7 are set in advance in the image area. In the captured image of the CCD sensor 3, The luminance waveform of this line A2 is acquired. In a state in which the plate 5 is not fogged, the luminance waveform of the line A2 is, for example, as shown in FIG. 5A, a dark color pattern waveform (for example, a waveform of a concave portion) and a light color pattern waveform. It will appear alternately. In this waveform, for example, the difference between the maximum luminance of the image obtained from the light color pattern and the minimum luminance of the image obtained from the dark color pattern is the signal intensity amplitude a (reference amplitude). For example, when the luminance changes by a certain value or more. The pixel width is defined as a slope b (reference slope). On the other hand, in the state in which the plate 5 is cloudy, as shown in FIG. 5B, in the luminance waveform, the difference between the maximum luminance of the image obtained from the light color pattern and the maximum luminance of the image obtained from the dark color pattern. However, the amplitude A ′ is smaller than the amplitude a, and the pixel width (inclination) when the luminance changes by a certain value or more becomes an inclination B ′ larger than the inclination b (the edge is rounded). For this reason, in this embodiment, the plate 5 is fogged when the ratio of amplitude and inclination in the image signal in each state is satisfied and the condition of A ′ / a <C or b / B ′ <D is satisfied. Is determined. Specifically, a, b, C, and D are values for specifying the degree of fogging in the cloudy state and are constants that can be arbitrarily determined. Therefore, in S4, A ′ is When it is smaller than the predetermined amplitude threshold value and B ′ is larger than the predetermined inclination threshold value, it is determined as cloudy. Note that the determination example of S4 is not limited to this. For example, when A ′ is smaller than another amplitude threshold, it is determined to be cloudy, or when B ′ is larger than another inclination threshold, it is determined to be cloudy. Good.
In the present embodiment, the control circuit 20 corresponds to an example of a “cloudiness detection unit”, and functions to detect the degree of cloudiness of the plate 5 based on the result of imaging a bright and dark pattern by the CCD sensor 3.

  If it is determined in S4 that no fog has occurred, the process proceeds to No in S4, and the fog removal process is terminated. On the other hand, if it is determined in S4 that fog is occurring, the energization process of the antenna 11 is performed in S5, and the process of removing the fog of the plate 5 is performed. Specifically, the control circuit 20 and the transmission circuit 32 cause a current (a constant current or a current that can fluctuate) to flow through the antenna 11 for a certain period of time, causing at least the resistance element (heating element) 12a to generate heat in the antenna 11, By transferring the heat to the adjacent plate 5, the fog generated on the plate 5 is removed using heat. Then, when the energization process of S5 ends, the defogging process ends.

  Note that the control circuit 20 and the transmission circuit 32 correspond to an example of an “energization unit”, and a current is passed through the antenna 11 on the condition that a predetermined clouding detection result is obtained by the clouding detection unit. The heating element) 12a functions to generate heat. In addition, an energization circuit such as a constant current circuit may be provided separately from the transmission circuit 20, and a constant current or the like may be supplied to the antenna 11 by the constant current circuit during the energization process in S5.

[Second Embodiment]
Next, a second embodiment will be described with reference to FIG.
In the second embodiment, as shown in FIG. 7, the configuration of the antenna 111 is different from that of the first embodiment, and other configurations are the same as those of the first embodiment. Therefore, configurations other than these (same points as in the first embodiment) are denoted by the same reference numerals as those in the first embodiment, and detailed description thereof is omitted.
As shown in FIG. 7, the antenna 111 of the second embodiment has an annular shape in which a resistance element (heating element) 112 a is continuously arranged in a configuration that at least partially surrounds the opening 10 a of the substrate 10. . If the resistance element 112a is continuously arranged in such a configuration that surrounds the opening 10a of the substrate 10, the heat from the heating element 112a is easily transmitted to the portion of the plate 5 in the vicinity of the opening 10a. Heat is also easily transmitted to the vicinity of the center portion of the plate 5 that is difficult to be opposed (portion corresponding to the opening region). As a result, in the plate 5, not only the vicinity of the opening 10a but also the fog near the center can be more effectively removed.

[Other Embodiments]
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.

  In the first embodiment, the temperature detected by the temperature detection element 50 is equal to or higher than a predetermined temperature, and further, the plate 5 is clouded based on the imaging result of the design portion 7 by the CCD sensor 3. Although it is configured to perform the energization process of the antenna 11 when determined by the clouding detection unit, it may be configured to perform the energization process of the antenna 11 without performing the clouding detection determination when the temperature is equal to or higher than a predetermined temperature. Good. That is, in the flowchart shown in FIG. 6, the process of S2 to S4 is omitted and the defogging process is performed. In this processing example, when the temperature detected by the temperature detection element 50 is equal to or higher than the predetermined temperature, the process proceeds to Yes in S1, and in S5, the energization process of the antenna 11 is performed and the fogging of the plate 5 is removed. I do. In such a configuration, the plate 5 can be warmed when the temperature near the case 2 reaches a predetermined temperature and clouding is likely to occur, and the clouding can be efficiently removed in an environment where clouding is likely to occur. Can do.

  In the first embodiment, the temperature detected by the temperature detection element 50 is equal to or higher than a predetermined temperature, and further, the plate 5 is clouded based on the imaging result of the design portion 7 by the CCD sensor 3. When it is determined by the clouding detection unit, the antenna 11 is energized. However, the energization unit flows current to the antenna 11 on the condition that the suspension time of energization of the antenna 11 reaches a certain time, The heating element 12a may be configured to generate heat. That is, in the flowchart shown in FIG. 6, instead of the processes of S <b> 1 to S <b> 4, a process for determining whether or not the suspension time of energization to the antenna 11 has reached a certain time is performed. In such a configuration, it is possible to periodically remove the fog by causing the heating element 12a to generate heat, and it is easy to maintain a state in which fog does not occur.

  In the first embodiment, the temperature detection element 50 detects the temperature at a predetermined position in the case 2 and determines whether or not the temperature is higher than the predetermined temperature (that is, the temperature at the predetermined position in the case 2). However, the temperature detection element 50 is provided inside and outside the case 2 so that the temperature difference between the inside and outside of the case 2 is greater than or equal to the predetermined value. It is good also as a structure which determines whether it is (that is, the structure which determines whether the electricity supply conditions that the temperature difference inside and outside of case 2 becomes more than a predetermined value are satisfied). That is, in the flowchart shown in FIG. 6, instead of the process of S <b> 1, a process for determining whether or not the temperature difference detected by the temperature detection element 50 inside and outside the case 2 has reached a predetermined value is performed. With such a configuration, the plate 5 can be warmed when the temperature difference between the inside and outside of the case 2 reaches a predetermined value and clouding is likely to occur, and the situation where clouding is likely to occur can be grasped more accurately and efficiently. The fog can be removed.

  In the first embodiment, the heat generating element configured as a part of the antenna 11 is illustrated as a method of transferring heat to the plate 5, but is not limited to this example. For example, although the heating element does not function as an antenna, a heating element that is electrically connected to the antenna 11 and generates heat when a current flows through the antenna 11 may be used.

  The antenna 11 and the heating element 12a may be arranged on the plate 5 side. In this case, it is desirable that the heating element 12a is in close contact with the plate 5 in order to transmit the temperature.

DESCRIPTION OF SYMBOLS 1 ... Information code reader 2 ... Case 2a ... Reading port 3 ... CCD sensor (imaging part)
DESCRIPTION OF SYMBOLS 5 ... Plate 7 ... Design part 10 ... Board | substrate 10a ... Opening part 11, 111 ... Antenna 12a, 112 ... Resistance element (heating element, heating part)
20 ... Control circuit (decoding unit, energization unit, fogging detection unit, heating unit, communication unit)
30 ... Communication processing unit (communication unit)
32 ... Transmission circuit (energization section)
40 ... Reading processing unit (decoding unit)
50. Temperature detecting element (temperature sensor)
C ... Information code T ... Non-contact communication medium

Claims (11)

A case with a reading port;
An imaging unit that is housed inside the case and can image an information code outside the case through the reading port;
A light transmissive plate disposed between the reading port and the imaging unit and closing the opening of the case;
A decoding unit for decoding the information code based on the captured image obtained by the imaging unit;
A substrate on which an antenna is mounted and which is disposed oppositely in the vicinity of the plate;
A heating element that is arranged as a part of the antenna or electrically connected to the antenna on the substrate, and generates heat when the antenna is energized,
A communication unit that transmits and receives electromagnetic waves via the antenna and communicates with a non-contact communication medium through the electromagnetic waves;
A current-carrying part that causes a current to flow to the antenna when a predetermined energization condition is satisfied, and heats the heating element;
An information code reading device comprising:   The information code reader according to claim 1, wherein the substrate or a component fixed to the substrate is disposed in contact with an inner surface of the plate. An opening is formed in the substrate,
The imaging unit is configured to be able to image the information code through the opening,
The heating element comprises a resistance element,
3. The information code reading device according to claim 1, wherein the antenna has an annular shape in which the resistance element is continuously arranged in a configuration that at least partially surrounds the opening. An opening is formed in the substrate,
The imaging unit is configured to be able to image the information code through the opening,
The heating element comprises a resistance element,
3. The antenna according to claim 1, wherein the antenna includes a plurality of the resistance elements connected in series at intervals, and is arranged in a ring shape so as to surround the opening. 4. Information code reader. A temperature sensor is provided inside or outside the case,
The current-carrying unit causes a current to flow to the antenna and heats the heating element on condition that the temperature detected by the temperature sensor reaches a predetermined temperature. The information code reading device according to any one of the above. A temperature sensor capable of detecting the temperature inside and outside the case is provided;
The current-carrying unit causes a current to flow to the antenna and generate heat by causing the current to flow to the antenna on the condition that the temperature difference between the inside and outside of the case detected by the temperature sensor reaches a predetermined value. The information code reading device according to claim 4.   7. The heating unit according to claim 1, wherein the energization unit causes a current to flow through the antenna on the condition that a suspension time of energization to the antenna reaches a certain time, and causes the heating element to generate heat. An information code reading device according to claim 1. A haze detection unit that detects a haze degree of the plate based on an image outside the plate obtained by the imaging unit;
8. The heating device according to claim 1, wherein a current is supplied to the antenna and the heating element is heated on condition that a predetermined clouding detection result is obtained by the clouding detection unit. The information code reading device described. A case with a reading port;
An imaging unit that is housed inside the case and can image an information code outside the case through the reading port;
A light transmissive plate disposed between the reading port and the imaging unit and closing the opening of the case;
A decoding unit for decoding the information code based on the captured image obtained by the imaging unit;
A substrate on which an antenna is mounted and which is disposed oppositely in the vicinity of the plate;
A communication unit that transmits and receives electromagnetic waves via the antenna and communicates with a non-contact communication medium through the electromagnetic waves;
A fog detection unit that detects the degree of fogging of the plate based on an image outside the plate obtained by the imaging unit;
A heating part that heats the plate on the condition that a predetermined fogging detection result is obtained by the fogging detection part;
An information code reading device comprising: A design portion made of a predetermined shape, pattern, color, or combination thereof is formed as a part of the case or as a portion fixed to the case at a position facing the plate outside the plate. And
The imaging unit is configured to be able to image the design portion via the plate,
10. The information code reading device according to claim 8, wherein the fogging detection unit detects a degree of fogging of the plate based on an imaging result of the design unit by the imaging unit. The design part has a light and dark pattern including a light color pattern and a dark color pattern formed on the plate side,
The information code reading apparatus according to claim 10, wherein the fogging detection unit detects the degree of fogging of the plate based on the imaging result of the bright and dark pattern by the imaging unit.

Images