JPH0245815A - Optical neuro-computer - Google Patents

Abstract

PURPOSE:To enable an optical system to be one system by converting the transmitted light of a space optical modulator to an electric signal and after that, separating the signal. CONSTITUTION:Now, a space optical modulator 10 is modulated simultaneously to a positive value Tij<(+)> of a Tij matrix and a negative value Tij<(-)> by angular frequencies omega1 and omega2 respectively. Namely, it can be expressed that [Tij<(+)>cosomega1 t+Tij<(-)>cosomega2t]. When a (j)-th row of the space optical modulator 10 is irradiat ed with a (j)-th light emitting diode 1 and the light of an (i)-th row in the space optical modulator 10 is received in an (i)-th photo-detecting element 3, a signal is obtained so as to be Ui=SIGMATijVj=SIGMA(Tij<(+)>Vjcocomega1t+Tij<(-)>Vjcosomega2t). This signal is passed through a band pass filter 11 and the components of the angular frequencies omega1 and omega2 are separated. After that, the signal is rectified by a rectifier 12 and it is obtained that Ui<(+)>=SIGMATij<(+)>Vj, Ui<(-)>=SIGMATijTij<(-)>Vj. These signals are subtracted by a differential amplifier 4 and threshold processing is executed by a comparator 5. Then, the signals are fed back to the light emitting diode 1.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention imitates the neural network of living things and achieves the use of light wave technology in computers (eurocomputers) having associative functions, pattern recognition functions, etc. This is related to a light neurocomputer.

[Conventional technology]

Figure 3 shows, for example, a publication (IEICE Optical and Quantum Electronics Study Group Material 0QE87-174 (1988
)) is a configuration diagram of a conventional light-associative neurocomputer shown in FIG. In the figure (1a).

(1b) Fi light emitting diode array, (2a),
(2b) is an optical mask, (5a) and (5b) are light receiving element plays, (4) is a differential amplifier, (5) is a comparator,
(6) is incomplete information input.

+71 is complete information output.

Next, the operation will be explained. FIG. 3 shows the basic configuration of a light-associative neurocomputer. Light-emitting diode plays (1a) and (lb) irradiate fan-shaped light onto optical masks (2a) and (2b). The light emitting diode play (1a), (1b) is a kind of vector V=(Vl, V2...vi) representing the state of 1 or 0, depending on whether each element is lit or clear.

vn). Optical mask (2a), (2
b) is divided into nxrl elements, and each element has a different light transmittance.
ij), and the light receiving element array (3b), (sb
) is a kind of nohect/l/U:=(Ul, U2. ””
Ul-...Un). The first light emitting diode illuminates the j-th row of the optical mask, and the i-th row of the optical mask
When the i-th light receiving element receives the light in the column.

Ui = ΣTijVj Vector and matrix operations can be performed.

A neurocomputer stores information on the connection strength between each neuron. In this light-associative neurocomputer, information is stored in the transparent straw T of the optical mask. The information storage rules are based on the Hop field model.

Tij : Σ(2yIsl −t ) (2yj(
s) is given by 1). Tij can take both positive and negative values, but since negative values cannot be handled optically, the positive value TiJ (+1 and negative value Ti
Two optical systems (Ui(+l U
If-)) is produced, and the difference Ui: IJi(+1-Ui(-1) is obtained by the differential amplifier (4). This output signal is subjected to threshold processing by the comparator (5) as vi=θ(Ui ) however.

After 1 light emitting diode array (1a), (1b)
are providing feedback.

In this way, 0, for example, the optical mask (2a).

If three types of information corresponding to alphabets A, J, and H are stored in (2b), the light emitting diode (1a
), (+b) even if you input incomplete information 0, for example A', K after repeating feedback.

The output displays the information A closest to the input information A' as the complete output.

To put this in other words, when the energy of the system takes a minimum value with accumulated information A, J, and E, and incomplete information is given, the entire system changes so that the energy near that value takes a minimum value. (by changing the blinking state of the light emitting diode play).

[The problem that the invention attempts to solve! Problem] Since the conventional optical neurocomputer is configured as described above,
There is a problem in that two optical systems are required to correspond to the positive and negative values of the Tij matrix, and the system is complicated.

The present invention was made to solve the above-mentioned problems, and an object of the present invention is to obtain an optical neurocomputer that can have a single optical system.

[Means to solve the problem]

The optical neurocomputer according to the present invention includes a light emitting element array that blinks according to the state vector of neurons, a frequency or phase that is different for positive values and negative values of stored information, or the above-mentioned positive values.

A correlation matrix is realized by multiplexing and driving negative values by alternating time division, and the light from the light emitting element array is modulated to transmit the product signal light of the state vector of the neuron and the correlation matrix. A spatial light modulator, a light-receiving element that receives the transmitted light from the spatial light modulator and obtains the sum of the product signals, and discriminates the output signal of the light-receiving element array to obtain the positive value.

A signal processor that obtains a signal corresponding to a negative value, a differential amplifier that obtains the difference between the positive value obtained by this signal processor, a signal corresponding to a negative value, and a value of the difference obtained by this differential amplifier. It is equipped with a comparator that performs threshold processing and feeds back to the light emitting element array.

[Effect]

In the spatial light modulator of this invention, the positive and negative values of the Tij matrix are expressed in a multiplexed manner. One system is sufficient.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, (1) is a light emitting element array, that is, a light emitting diode array, and (3) is a light receiving element array.

(4) is a differential amplifier, (5) is a comparator, and α0 is a spatial light modulator.

all is a signal processor, that is, a bandpass filter, α2
is a rectifier, and α3 is a driver for a spatial light modulator.

Next, the operation will be explained. The basic principle is the same as the conventional example. In this embodiment, a spatial light modulator a1 that can be modulated by an external signal is used instead of an optical mask. Now, the spatial light modulator αe is set to the positive value Ti of the T11 matrix (+)
and the negative value Ti j (-1, respectively, the angular frequency ω
1. Simultaneously modulate at ω2. Namely.

It is expressed as When the j-th light emitting diode (1) illuminates the j-th row of the spatial light modulator αG, and the i-th light receiving element (3) receives the light from the i-th column of the spatial light modulator a, IJi = !
A signal 'Ti j Vj' is obtained. This signal is filtered through a bandpass filter f
After separating the components of angular frequencies ω1 and ω2 through i9, they are rectified by a rectifier α2.

Namely.

The signals U, (+l == , Tij (+l vJ) are obtained. These signals are subtracted by the differential amplifier (41) to obtain the signal (4"l, (-1 Ui=Ut Ul), which is is subjected to threshold processing using a comparator (5).

Feedback to the light emitting diode array (1).

In the above embodiment, the spatial light modulator (I [I) is driven by a frequency multiplexed signal, but if the signals have the same frequency but different phases, for example, a positive value of Tij is: , f+
1 T13 CQSωt, negative value is Tij'-'sinωt
It may also be driven as follows. At this time, positive values and negative values of 'l''ij can be distinguished by phase (phase modulation method).

Also, the school may open at 9 o'clock. An example is shown in FIG.

In the figure, (0) is a light emitting diode playback, (3) is a light receiving element array, (4) is a differential amplifier, and (5) is a comparator.

No is a spatial light modulator, (14a) and (14b) are spatial light modulator drivers, (1sa) and (15b) are pulse generators, and (16a) and (16b) are H sample and hold amplifiers.

Spatial light modulator ai#:t its driver (14a) (1
4b), the pulsers (15a) and (15b) alternately pulse drive with Tij(+) and Ti](-) signals. At this time, the output of the light receiving element +31 is sent to the spatial light modulator a.
It is recommended to sample and hold in synchronization with the 1B drive signal pulse.

7ij matrix positive value Tij (+1. negative value Tij (-
1 can be separated. The subsequent operation is the same as the embodiment shown in FIG.

〔Effect of the invention〕

As described above, according to the present invention, there is provided a light emitting element array that blinks in accordance with the state vector of a neuron.

A correlation matrix is realized by driving the positive values and negative values of the stored information at different frequencies or phases, or by multiplexing and driving the positive values and negative values by mutual time division, and the light emitting element A spatial light modulator that modulates the light from the play and transmits the product signal light of the state vector of the neuron and the correlation matrix, and a light receiving element that receives the transmitted light from the spatial light modulator and obtains the sum of the product signals. array, a signal processor that discriminates the output signal of this light receiving element array to obtain signals corresponding to the positive and negative values, and a difference that obtains the difference between the signals corresponding to the positive and negative values obtained by this signal processor. Since it is equipped with a dynamic amplifier and a comparator that thresholds the difference value obtained by this differential amplifier and feeds it back to the light emitting element array, only one optical system is required, which simplifies the device and reduces the size of the device. This has the effect of facilitating scale-up.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an optical neurocomputer according to an embodiment of the present invention, FIG. 2 is a block diagram showing an optical neurocomputer according to another embodiment of the present invention, and FIG. 3 is a block diagram showing a conventional optical neurocomputer. In the figure, ill, (1a) and (1b) are light emitting diode arrays, (2a) and (2b) are optical-qX arrays, and tag, (5a). (5b) is a photodetector array, (4) is a differential amplifier, (5
) is a comparator, (61 is an incomplete information input, (7) is a complete information output. aG is a spatial light modulator, all is a bandpass filter, a
ri is a rectifier, +13. (14a), (14b
) is driver @ (15a). (15b) Fi pulse generator, (16a), (1
6b) is a sample and hold amplifier. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims] An optical neurocomputer that performs a product-sum operation of a neuron state vector and a correlation matrix, comprising: a light emitting element array that blinks in accordance with the neuron state vector; and positive and negative values of stored information. The correlation matrix is realized by multiplexing and driving the positive and negative values at different frequencies or phases, or by alternating time division, and the light from the light emitting element array is modulated to generate the neuron. a spatial light modulator that transmits a product signal light of a state vector and a correlation matrix; a light receiving element array that receives the transmitted light from this spatial light modulator and obtains the sum of the product signals; and a valve that receives the output signal of this light receiving element array. A signal processor that separately obtains signals corresponding to the positive and negative values, a differential amplifier that obtains the difference between the signals corresponding to the positive and negative values obtained by this signal processor, and An optical neurocomputer comprising a comparator that performs threshold processing on the difference value and feeds it back to the light emitting element array.