JPH02242238A - System for direct transmission of information in multimode light guide image - Google Patents

Abstract

PURPOSE:To allow the direct transmission of image informations by using a piece of multimode light guide by adding optical filters consisting of plural optical fiber elements which allow the transmission or reflection of light rays of different wavelengths to a signal transmission side and reception side. CONSTITUTION:A transmitted light signal 2 from the optical image information 1 is divided to sub-transmitted light signals 2-1 to 2-4 coupled to the optical filter elements 17-1 to 17-4 of the transmission side optical filter 17 and thereafter, the signal passes the respective optical filter elements 17-1 to 17-4 and is made incident on the multimode light guide 4 in which the signal propagates. The received light signal 5 propagated therein is separated to sub-light signals 5-1 to 5-4 coupled to the four optical filter elements 18-1 to 18-4 of the reception side optical filter 18; thereafter, the signals are coupled to a photodetecting element array 7. The electric signal 19 obtd. in the array 7 is processed in a neural network 8 and an output signal 9 is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a multimode optical waveguide image information direct transmission system that directly transmits optical image information using a multimode optical waveguide.

[Prior Art] Conventional technologies of this type include Japanese Patent Application No. 63-244391 entitled "Optical Image Information Direct Transmission System" which was separately proposed by the inventor of the present invention, or disclosed by the inventor of the present invention. This was shown in a paper (Matsumoto, Noguchi, "Direct transmission of multimode optical guide image information using neural processing", Institute of Electronics, Information and Communication Engineers, Optical Communication Systems Study Group material, March 1989).

In this type of conventional technology, for example, as shown in FIG.
A transmitted optical signal 2 from optical image information 1 to be transmitted on the transmitting side was directly coupled to a multimode optical waveguide 4 via a lens system 3. Furthermore, on the receiving side, the received optical signal 5, which is the light emitted from the multimode optical waveguide 4, is directly coupled to the photodetector array 7 via the lens system 6. The output of the photodetector array 7 was processed through a neural network 8, and a final output signal 9 was obtained from the output port 10.

Figure 8 shows typical 4Ps of neural network 8.
Here, 11 is a human-powered boat, I2 is a processing element, and 13 is an addition I that constitutes the processing element 12.
14 is a nonlinear processing section that also constitutes the processing element 12; 15 is a connection element that connects the processing elements 12; and 16 is an output port. The addition IN processing section 13 has a function of weighting signals input from a plurality of connection elements 15 connected thereto and adding them. In addition, the nonlinear processing unit 14 performs nonlinear processing on the signal input from the addition processing unit 13, that is, for example, when the level of the input signal is higher than a certain threshold, it outputs an output signal “B”, When it is small, processing is performed to output an output signal "0".

In the example shown in FIG. 8, the input boat 11 and output boat 16 are separated;
Neural networks with other structures, such as those in which 11 and 16 are shared, have also been proposed.

As is well known, a neural network can freely set the relationship between input signals and output signals by appropriately setting internal parameters. In addition, neural networks can also prevent output signals from changing in response to small changes in input signals, as seen in functions such as associative memory and recognition.

Furthermore, as seen in the learning function, by exemplifying several input/output signal combinations to the neural network, internal parameters can be automatically changed to obtain a desired input/output relationship. Therefore, according to the configuration shown in FIG. 7, image information disturbed by the multimode optical waveguide l can be restored by the neural network 8.

In the transmission system shown in FIG. 7, if the light rays from each pixel of optical image information 1 are set to enter the multimode optical waveguide 4 at different incident angles, it is possible to directly transmit this optical image information 1. Become. However, in this case, the linear light beam emitted from one pixel of the transmitting side optical image information 1 is observed as a conical light beam when emitted from the multimode optical waveguide 4 on the receiving side. Therefore, for example, even if the character pattern "6" as shown in FIG. 9 is transmitted, the emitted light pattern observed on the receiving side will be a concentric circle pattern as shown in FIG. 10, and the original character pattern "6" will be transmitted. It will be significantly different from 6″. However, after this concentric pattern is detected by the photodetecting element array 7, signal processing is performed by the neural network 8, so that the original character pattern can be reproduced.

[Problems to be Solved by the Invention] The problem with such conventional technology is that even though the character patterns on the transmitting side are different, the concentric circle patterns on the receiving side are the same, resulting in the signal being distorted. For example, it may become impossible to play the 9th
The character pattern “6” in the figure and the character pattern “9” in Figure 11
This is the case with “0”. Since both character patterns are rotationally symmetric, the concentric patterns on the receiving side are the same pattern. 0 Even if the character patterns are not rotationally symmetric, for example, in the case of the character patterns “U” and “C” etc., the respective receiving side concentric circle patterns are extremely similar patterns. For this reason, there is a limit to the ability to transmit a large number of various types of optical image information using conventional techniques.

Therefore, an object of the present invention is to provide a multi-mode optical waveguide for direct image information transmission, which has high resolution and can directly transmit optical image information without being affected by disturbance, in a transmission system using a multi-mode optical waveguide. The aim is to provide a system.

[Means for Solving the Problems] In order to achieve such an object, the present invention provides a multimode optical waveguide capable of simultaneously transmitting a plurality of modes, and a plurality of optical filters that transmit or reflect light of different wavelengths. - A first optical filter composed of elements, each of which serves as a plurality of sub-optical image information signals in which the optical image information signal is spatially divided at one end of the multimode optical waveguide. a first optical filter configured to be guided by a plurality of optical filter elements; a first optical means for inputting a plurality of sub-optical image information signals output from the first optical filter into a multimode optical waveguide; a second optical means for receiving an optical image information signal propagating within the multimode optical waveguide and obtained as an output at the other end of the multimode optical waveguide;
a second optical filter comprising a plurality of optical filter elements that transmit or reflect light of different wavelengths, the output light from the second optical means being spatially separated into each of the plurality of optical filter elements; a second optical filter that is guided as a plurality of sub-optical image information signals in the form of a plurality of sub-optical image information signals; A neural network is a neural network that includes a detectable photodetector array and a neural network that has a recognition and learning function for input signals and receives electrical signals obtained from the photodetector array. - It is characterized by using the signal obtained from the network as the final output signal.

[Function] In the present invention, a multimode optical waveguide is used, and a signal obtained from the emitted light is passed through a neural network to reproduce optical image information. , an optical filter composed of a plurality of optical filter elements that transmit or reflect light of different wavelengths is arranged. In contrast, in conventional optical image information direct transmission systems using multimode optical waveguides and neural networks, no optical filters are placed on the transmitting or receiving sides, and the optical image information to be transmitted is multimode. The optical image information received from the multimode optical waveguide was directly coupled to the light receiving element array.

However, here, the neural network refers to multiple processes realized by an addition processing section that weights and adds signals from multiple human-powered boats, and a nonlinear processing section that performs nonlinear processing on input signals. It is a signal processing network configured by a plurality of connection elements that connect these plurality of processing elements.

According to the present invention, image information can be directly transmitted using one multimode optical waveguide. Therefore, compared to methods using conventional optical communication technology, there is no need to prepare an optical-to-electrical converter or an electric-to-optical converter on the input end side of the optical waveguide, and the configuration of the transmission system can be simplified. can.

[Embodiments] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, where 1 is optical image information, 2 is a transmitted optical signal, 3 is a lens system, 4 is a multimode optical waveguide, 5 is a received optical signal, and 6 is a lens system. , 7 is a photodetector array, 8 is a neural network, 9 is an output signal, ! 0 is an output port, 1f is a transmitting side optical filter, 18 is a receiving side optical filter, and 19 is a photodetector array output. In the example of FIG. 1, the transmitting side optical filter 17 and the receiving side optical filter 18 are each composed of four optical filter elements l to 17-4 and 18-1 to 18-4. Optical filter element 17-1.
18-1 is wavelength λ1, optical filter element 17-2
．． l11-2 is wavelength λ2, optical filter element 17
-3.18-3 is wavelength λ3, optical filter element 1
7-4.18-4 each has a characteristic of transmitting light of wavelength λ4.

The transmitted optical signal 2 from the optical image information 1 is sent to the transmitting side optical filter 1
7 four optical filter elements 17-1 to 17-4
After being divided into sub-transmission optical signals 2-1 to 2-4 to be coupled to the respective optical filter elements 17-1 to 1
7-4, enters the multimode optical waveguide 4, and propagates therein. For example, if the optical image information is a character pattern “6”
When the character pattern is "9", each sub-optical number 2-1 to 2-4 becomes a divided signal as shown in FIGS. 2 and 3.

The received optical signal 5 after propagating through the multimode optical waveguide 4 is
Sub-optical signals 5-1 to 5- coupled to four optical filter elements 18-1 to 18-4 of the receiving side optical filter 18
After being separated into 4 parts, the photodetecting element array 7 is coupled to the photodetecting element array 7. The electrical signal 19 obtained by the photodetector array 7 is guided to the neural network 8. These electrical signals 19 are processed within the neural network 8, so that
An output signal 9 is obtained from the output boat 10. Optical image information 1
Lens systems 3 and 6 may be provided between the multimode optical waveguide 4 and the multimode optical waveguide 4 and the photodetector array 7, respectively, to focus the light as necessary. .

FIG. 4 shows another embodiment of the present invention. Here, in the multimode optical waveguide 4, even if the optical image information 1 is a two-dimensional pattern as shown in FIG. 9 or FIG. wave path 4
Since information elements with the same propagation angle within are mixed with each other, the image information becomes essentially one-dimensional information in the radial direction, as shown in FIG. 10. From this, The photodetecting element array 7 of the receiving section may be a photodetecting element array arranged in a two-dimensional array as shown in FIG. 1, or may be a photodetecting element array arranged in a one-dimensional array as shown in FIG. Arrays 7-1 to 7-4 may be arranged radially at intervals of 90 degrees for each optical filter element 18-1 to 18-4.

5 and 6 show the pattern of the sub-reception optical signal 5-1 in the optical system according to the present invention, for example, the optical system shown in FIG. and are shown in correspondence with the character pattern "9". In the case of the prior art, the emitted light patterns corresponding to the character pattern "6" and the character pattern "9" are both shown in FIG. On the other hand, in the present invention,
As shown in FIGS. 5 and 6, it can be seen that the patterns of the sub-reception optical signal 5-1 are different for both character patterns. The same thing applies to other sub reception signals 5-2.
．． 5-3.5-4 is also true. Therefore, by combining these multiple sub optical signals to the photodetecting element array 7 to obtain the final output signal 9, rotationally symmetrical It can be seen that the optical image information transmission function of the transmission system can be improved, such as mutual identification of related optical image information.

In the above-described embodiment, the number of elements in the transmission-side optical filter 17 and the reception-side optical filter 18 was set to four, but the number of elements can be arbitrarily selected as long as it is two or more. In that case, the most effective method for dividing the transmitting (g-side optical filter 17 and receiving-side optical filter 18) into a plurality of elements is to divide them radially.

Furthermore, in the above-described embodiment, a configuration is shown in which transmission-type optical filters are used as the transmission-side optical filter 17 and the reception-side optical filter 18, but it goes without saying that a reflection-type optical filter such as a diffraction grating may also be used. It is also possible to use

Furthermore, when the neural network 8 is composed of hardware consisting of an electronic circuit or an optical circuit,
Alternatively, it also includes a case where the computer is configured by a computer having input/output terminals and controlled by software.

[Effects of the Invention] As described above, according to the present invention, image information can be directly transmitted using one multimode optical waveguide.

Therefore, compared to methods using conventional optical communication technology,
There is no need to place the optical/electrical converter or the electrical/optical converter at fJm on the incident end side of the optical waveguide, and the configuration of the transmission system can be simplified. Therefore, the present invention is effective when realizing a sensor for detecting two-dimensional image information.

In addition, with this type of conventional technology, it was impossible to identify image information that has a rotationally symmetrical relationship, but the present invention makes it possible to identify a large number of image information using one optical fiber. The present invention is effective when transmitting image information.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing one embodiment of the present invention, and FIG.
FIG. 3 is an explanatory diagram of the sub-transmission optical signal of the present invention corresponding to the character pattern "6"; FIG. 4 is an explanatory diagram of the sub-transmission optical signal of the present invention corresponding to the character pattern "9"; FIG. FIG. 5 is a block diagram showing another embodiment of the sub-reception optical signal 5-1 corresponding to the character pattern "6".
6 is an explanatory diagram of the pattern of the sub-reception optical signal 5-1 corresponding to the character pattern "9", and FIG. 7 is an explanatory diagram of the pattern of the sub-reception optical signal 5-1 corresponding to the character pattern "9". Figure 758 is a configuration diagram showing a typical example of the neural network. Figure 9 is an explanatory diagram of the character pattern "6" of optical image information on the transmitting side. Figure 10 is an illustration of the optical image information. FIG. 1 is an explanatory diagram of the emitted light pattern on the receiving side corresponding to the character pattern "6" of the information. FIG. 1 is an explanatory diagram of the character pattern "9" of the optical image information on the transmitting side. DESCRIPTION OF SYMBOLS 1... Optical image information, 2... Transmission optical signal, 2-1 to 2-4... Sub-transmission optical signal, 3... Lens system, 4... Multimode optical waveguide, 5... - Received optical signal, 6... Lens system, 7... Photodetecting element array, 7-1 to 7-2... One-dimensional array of photodetecting elements, 8... Neural network. , 9... Output signal, lO... Output port, 11... Input port, 12... Processing element, 13... Addition processing section, 14... Nonlinear processing section, 15... Connection Element, 1δ... Output port, 17... Transmission side optical filter,

Claims (1)

[Claims] 1) A first optical filter comprising: a multimode optical waveguide capable of simultaneously transmitting a plurality of modes; and a plurality of optical filter elements that transmit or reflect light of different wavelengths, At one end of the multimode optical waveguide, the optical image information signal is guided to the plurality of optical filter elements as a plurality of spatially divided sub-optical image information signals, respectively. a first optical filter; a first optical means for causing a plurality of sub-optical image information signals outputted from the first optical filter to enter the multimode optical waveguide; At the other end of the multimode optical waveguide, a second optical means for receiving the optical image information signal obtained as an output, and a second optical means comprising a plurality of optical filter elements for transmitting or reflecting light of different wavelengths. a second filter, wherein the output light from the second optical means is directed to each of the plurality of optical filter elements as a plurality of sub-optical image information signals in a spatially separated form; an optical filter; a photodetection element array capable of receiving a plurality of sub-optical image information signals output from the second optical filter and detecting the intensity distribution of light; and having a recognition and learning function for input signals. A neural network comprising a neural network that receives an electrical signal obtained from the photodetector array, and a signal obtained from the neural network is used as a final output signal. Mode optical waveguide image information direct transmission system.