JPS6191779A - Optical information processor - Google Patents

Abstract

PURPOSE:To perform high-speed, complicate information processing by coupling plural light guide elements which have input/output characteristics controlled with external control light. CONSTITUTION:Light guide elements 31-1-31-3 change in propagation state of light between input and output with irradiation light from outside the light guide and arranged in a matrix on an LiNbO3 substrate 10 for the light guide. The light guide elements are coupled together through light guides 32-1-32-3 and controlled with external irradiation light beams 33-1-33-3 and light propagation among the elements is controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an optical information processing device that processes information using light.

[Prior Art] As a conventional optical information processing device of this kind, for example, as shown in FIG. 3
.

..., and optical waveguides or optical waveguide surfaces 22-1, 22-2, 22-3, . . . are formed between these elements. ..., and a control electrode 23 is connected to each of the optical waveguide elements 211, ....
-1.23-2.23-3°... are attached to each element 21-1.21-2. ...is controlled externally by electrical signals. As a result, these optical waveguide elements 21-1
．． 21-2. ...There is an attempt to process information by modulating waveguide light that propagates sequentially within the waveguide.

However, this method has the following drawbacks. That is, (1) A control electric signal is transmitted to each optical waveguide element 21-1.
．． 21-2. The corresponding wiring 23-1, 23-2. ... must be formed for each optical waveguide element, and signal interference is likely to occur between these wirings.

(2) Similarly, these wirings tend to pick up electromagnetic noise from the outside.

(3) When the number of optical waveguide devices is large, the wiring becomes complicated, and therefore the design and formation of the wiring, as well as the IC
It is difficult to

(4) The wiring itself is fixed and cannot be changed during use.

[Objective] Therefore, an object of the present invention is to overcome the above-mentioned drawbacks by appropriately controlling waveguide light without using electrical wiring to supply electrical signals to each leading waveguide element, and to achieve better results. An object of the present invention is to provide an optical information processing device that processes optical information at high speed.

Another object of the present invention is to provide an optical information processing device with improved insulation between control signals and input/output.

Still another object of the present invention is to provide an optical information processing device in which the information processing architecture is simplified by utilizing the spatial arrangement of optical waveguide elements.

[Structure of the Invention] In order to achieve the above object, the present invention includes an input waveguide, an output waveguide, and a controlled output light input from the input waveguide in response to external illumination light. Arranging a plurality of optical waveguide elements each having a control part for taking out the waveguide from the waveguide on an optical waveguide substrate, and irradiating external illumination light from outside the optical waveguide element to each control part of the plurality of optical waveguide elements. Accordingly, guided light propagating between a plurality of optical waveguide elements is controlled.

C Example The present invention will be described in detail below with reference to the drawings.

FIG. 1 shows the basic configuration of the optical information processing apparatus of the present invention, where 31-1.31-2.31-3. . . . is a leading waveguide element in which the propagation state of light between input and output changes under the control of illumination light from outside the waveguide.
It is placed on the o3 substrate 10. 32-1.32-2゜3
2-3, . . . are waveguides or waveguide surfaces that couple these elements, 33-1.33-2.33-3. ... is each element 31-1.31-2°31-3. ... are individually irradiated onto the waveguides 32-1, 32-2. ...This is external illumination light that controls the propagation of light between them.

Each optical waveguide element 31-1.31-2.31-3. ...
is light from outside the waveguide 33-1.33-2.33-3.・
... and each input/output characteristic is controlled by the waveguides 32-1.32-2.32-3. The processing of optical information is completed while the guided light of... propagates sequentially through these optical waveguide elements.

Each element constituting the optical information processing apparatus of the present invention will be described in detail below.

As shown in FIG. 3(a), the waveguide light used in the present invention generally has most of its power on the surface of the guiding waveguide substrate 10, which has a refractive index higher than that of the substrate 10. Confined within the layer 11, the optical waveguide substrate 1
It propagates in a direction parallel to the main surface of 0. Here, such a waveguide is called a planar waveguide. Alternatively, as shown in FIG. 3(b) or (C), a striped waveguide 12 may be arranged on the substrate 10, or the guided light may be
It may be a structure in which a striped waveguide IOA is formed integrally with the substrate 10 and is confined in a direction perpendicular to the substrate surface and a direction perpendicular to the propagation direction of the guided light. In the following, a waveguide having such a structure will be referred to as a rectangular waveguide.

In any case, Fig. 3(d) and (
As shown in e), other buffer layers 13 and 14 can be stacked above and below the planar waveguide 77711, or buffer layers 15 can be placed on both sides of the ridge-shaped waveguide 12, if necessary. Furthermore, any known waveguide of any structure can be used, such as a graded index waveguide.

The material of the optical waveguide substrate IO is the above-mentioned LiNbO3.
In addition to dielectric materials such as GaAs and the like, semiconductors such as GaAs can also be used depending on the purpose.

Optical waveguide element 31-1.31-2゜3 used in the present invention
1-3. The waveguides 32-1, 32-3, .
...Light illuminated from outside 33-1, 33-2.33
-3. The physical quantities that can be input or output include light intensity, light phase, light wavelength, light polarization plane, light spatial position and shape, A waveguide mode of light or the like can be used, and each of these physical quantities represents the information to be processed. Furthermore, the physical mechanism for modulating the guided light with the control light may be direct modulation or a case where the guided light is modulated after being converted into another physical quantity such as an electrical quantity. Alternatively, so-called optical bistability can also be used.

Specific examples of the planar waveguide type optical waveguide element used in the present invention are shown below.

In FIG. 4(a), 41 is a planar waveguide made of a material whose refractive index changes according to external irradiation light, and spatially uniform input guided light 42 is incident from the left. are doing. When there is no external irradiation light, the input waveguide light 42 passes through this optical waveguide element 41 as it is and outputs uniform waveguide light 43. By imaging control light 44 having a lens-like shape from the outside on this optical waveguide element 41 as shown in FIG. 4(b), the refractive index of a portion 41A irradiated with the control light changes. And this part 4
The guided light passing through 1A undergoes a phase change according to the product of its refractive index change and the distance of the passing portion. Therefore, the input guided light 42 is subjected to a lens action in the control light irradiation section 41A, and the output guided light 45 is spatially converged. here,
The lens-shaped control light can be generated using a light source 46 that emits light in a lens shape or an optical system 47 such as a surface light source, a slit, and a lens, as shown in the figure. Note that when the light source is close to the element 41, the optical system N can be omitted.

By focusing the control light 5o having a folded grating shape, the optical waveguide element 41 can function as a diffraction grating for the input waveguide light. Utilizing the diffraction of the input guided light by such a diffraction grating, the light intensity ratio between the undiffracted light and the diffracted light of each order (one diffracted light in the case of a Bragg type diffraction grating) in the output guided light, etc. can be controlled. It goes without saying that other known functions of general diffraction gratings, such as coupling of input guided light beams with two different propagation directions, can also be performed.

In the above two examples, the case where the intensity of the control irradiation light on the optical waveguide element is uniform has been described, but the irradiation light intensity may have a distribution.

That is, as shown in FIG. 4(d), the optical system 5 is emitted from the light source 51 having the distribution in the X direction as shown in FIG. 4(e).
When the control light 53 is made incident through the optical waveguide element 4
The refractive index in the X' force direction perpendicular to the propagation direction of the input waveguide light 42 of the portion 54 within 1 becomes as shown in FIG. The guided light 42 is spatially converged to obtain output light as in the case of FIG. 4(b). Note that the shape and intensity distribution of the control irradiation light used in this optical waveguide element are not limited to the illustrated example.

In this example, the substrate 41 can be formed of a phase-changing reversible photosensitive material such as thermoplastic.

In the example of the optical waveguide element above, we have described an element whose refractive index changes depending on the externally irradiated light, and therefore the phase of the guided light. However, this is just an example; , an optical waveguide element that changes the wavelength, polarization plane, waveguide mode, etc. can also be used. For example, $5 figure (a),
As shown in FIG. 5(b), it is also possible to attenuate a part of the incident guided light 59 by the irradiation light 58 as shown in FIG. 5('b).

In this example, the substrate 41 can be formed of a reversible photosensitive material with variable absorption rate, such as photochromics.

A specific example of the generation of control light for controlling the optical waveguide element used in the present invention will be described.

In the example shown in FIG. 6(a), a light beam 81 from a laser light source 60 or the like passes through an optical modulator 62, an optical system 63 such as a mirror or a lens, and then is irradiated onto the element 41 as control light 64. Instead of such a configuration, the light source 6
It is also possible to guide the light from 0 to a desired position of the element 41 using an optical fiber. In the example shown in FIG. 6(b), a light pattern 65 to be irradiated onto the optical waveguide element 41 is irradiated with uniform irradiation light from, for example, a surface light source using a liquid crystal display device itself that is optically or electrically controlled. By modulating the light through a spatial modulator such as a shutter, or by lighting up a light source array in which a plurality of point light sources are two-dimensionally arranged, which corresponds to a desired pattern, the The optical system 66 forms an image of the optical waveguide element 41 at a predetermined location.

In FIG. 6(c), in order to obtain illumination light 67 for controlling the optical waveguide element 41, a laser beam 68 or the like is passed through a light wave conversion element 68 such as a hologram.

Next, we will discuss the input/output configuration of the guiding waveguide element when the guided light used in the present invention is confined also in a direction perpendicular to the propagation direction of the guided wave, such as in a square-shaped waveguide. explain. In this case, the optical waveguide element can be provided with a plurality of mutually independent inputs, referred to as input channels; it can likewise be provided with a plurality of output channels. Therefore, this type of optical waveguide device can be classified according to the number of input and output channels. The most practically important ones are shown in Figure 7(a).

Each is schematically illustrated in (b).

FIG. 7(a) shows a one-manpower, one-output device, and FIG. 7(b) shows a two-manpower, two-output device. The one-power, one-output element 70 has one input channel for receiving one input light 71 and one output channel for taking out one output light 72, and has two
The two output elements 73 have two input channels receiving two input lights 74 and 75 and two output lights 76 and 77.
It has an output channel to take out the . 78 is a control light to the element 70 or 73. The simplest example of the 1-input, 1-output element 70 is one in which the light amount ratio of the output guided light 72 to the input guided light 71 changes depending on the light amount of the control light 78, as shown in FIG. It is a kind of modulator.

On the other hand, the two-manufactured two-output element 73 generally has complicated input/output characteristics, but to give one example, the input light 74.
The light quantity ratio of the four combinations from 5 to 713.77 is as shown in FIG. 8(b). Such characteristics can be changed depending on the configuration of the element, for example, as shown in FIG. 8(C).
You can also do it like this.

The elements shown in FIGS. 7(a) and 7(b) can be constructed, for example, as will be described in detail later with reference to FIGS. 10(b) and 8, respectively.

Such an element can be realized by combining a photovoltaic element and a waveguide type optical coupler as shown in FIG. That is, in FIG. 9, optical waveguides 80 and 81 formed by Ti diffusion are arranged on a LiNbO3 substrate 10 so that some portions thereof are close to each other and parallel to each other, as shown in the figure.

Modulation electrodes 82 and 83 are arranged in parallel portions 80A and 81A, respectively. 84 is an amorphous silicon photovoltaic element integrated on the same substrate 10, 85 is its load resistance, and the electromotive force generated by inputting the control light 86 into the element 84 is applied to the electrodes 82 and 83. to control the ratio at which the two input lights are output to the two output channels.

In addition, in the explanation of these elements, input light.

Although both the output light is an analog quantity that can take any value,
The relationship between input and output can also be determined digitally by setting the value of the input light amount to a constant value.

Furthermore, it is clear that various general waveguide modulators controlled by electrical signals can be used in combination with the photovoltaic element as shown in FIG.

A first embodiment of the present invention is shown in FIG. 10(a).

This means that when X and al (i = 0.1, 2...=N) are given, aNXN+a, -, X'-'+ -+a,
This is part of a polynomial calculator whose purpose is to find +&6. Here, a waveguide 90 is placed on the LiNbO3 substrate 10.
-N,...,90-(ill).

9l-i-2;... and an adder such as a directional coupler.
....

-2, 94-i-1 and 94-i-2 are formed, and these branch waveguides are merged to form a waveguide..., 131-
Connect to (ill)-2°9l-i-2,... Planar electrodes 85 to 87 are provided at the branch part as shown in FIG. 10(b).
Place. ....

98-(ill), H-i,... are the substrates 10
Amorphous silicon photovoltaic device integrated in S
8 is its load resistance. Reference numeral 100 denotes an optical waveguide that performs optical delay, which is arranged closely or at a predetermined interval on the substrate IO, and in this waveguide, there is an optical tap that branches light to the element 88-1 corresponding to each element 98-1. , Directional coupler AS1. % + Kisukei 1 匈mu + / l + - j tunjin play seven j the control light with the sound of the sound, ..., x (t), x (t - τ
), . . . are sequentially converted into elements .
98-i, . . . and the electromotive force generated here is applied to the electrodes 95 to 87, and the branch portions .

94-i-1,... and..., 84-i-2,...
The intensity of the output light taken out to the waveguide 9l-i-2 is modulated by giving a phase difference between the waveguide 9l-i-2. In this example, the control light x(
Input waveguide light aHK'-'+aN-1 according to the light intensity of t)
! '+”alux+ al =-((…~C(aHx
"aN-+)x +aN-p+"' +81
+t)X”ai)x.In addition, the optical waveguide 100
Instead, an optical fiber may be used, and a light scattering portion may be provided corresponding to each element 98-1, which scatters only a portion of the light and transmits the other portion.

As a $2 embodiment of the present invention, a general-purpose optical crossbar switching device is shown in FIG. 11, in which waveguides 110-1,
110-2.・, 110-N,! :111-1,1
11-2.・, 111M are arranged in a grid pattern, and at each intersection there is a 2-man power, 2-output MX based on the principle shown in Figure 8.
N optical waveguide devices 112-11, 112-12.
..., 112-MN is provided. Reference numeral 113 denotes a light source array, for example, an LED array, which arranges light sources, for example, LEDs in a matrix, and controls the on/off of the control light 114 that is obtained through an optical system 115 to devices 112-11°... - Inject it into 112-MN.

In the illustrated example, the LED at the black circle in the light source array 113 lights up, the device at the corresponding position is irradiated with the control light 114, and the output direction of the input light changes.

As shown in FIG. 12, the optical waveguide device 112-IJ
Regarding, when the control light 114 from the outside is not irradiated, the input light to the input terminals ■ and ■ is output from the output terminals ■ and ■, respectively, but the control light 114 with a constant light amount
When 4 is irradiated, the input light to the input terminals ■ and ■ is taken out from the output terminals ■ and ■, respectively. Therefore, each input can be coupled to a corresponding output by irradiating the control light only to an element selected as necessary from among the NX8 devices 112-11 to 112-MW. In the case of FIG. 11, input l→output 2. The connections of input 2→output N and input N→output 1 are realized.

Such a general-purpose optical crossbar switching device is not only useful in many types of optical information processing, but can also be used as a switching device in general optical information transmission.

As an example of the optical information processing device of the present invention using the general-purpose optical crossbar switching device with the above configuration, in FIG. 11, the number of inputs and the number of outputs are set equal (NM),
By irradiating the control light so that one output is combined with one input in a ratio of 1:1, M-N outputs can be obtained by arbitrarily replacing N inputs. Such information processing can be used, for example, as a permutator in optical remainder processing operations.

Further, as an embodiment in which the present invention exhibits a more remarkable effect, a substituent for addition and subtraction in the above-mentioned optical remainder calculation will be described. Addition and subtraction in remainder operations can be realized using a circular permutation device. These facts make it possible to simplify the structure of the illumination light pattern in the aforementioned general-purpose optical crossbar switching device, and furthermore, it is possible to simply move the entire illumination light pattern spatially in one direction by means such as scanning. It is possible to change the addend or subtrahend in the remainder adder or remainder subtracter by simply FIG. 13(a) shows an example in which the addend is 2 in a remainder adder when the modulus of the remainder operation is 5. In the figure, the optical waveguide elements at the intersections of the gratings are They are arranged at equal intervals. Control light is irradiated onto the optical waveguide element indicated by a black circle. The input/output characteristics of each optical waveguide element change depending on the presence or absence of irradiation light, as explained in FIG. 12. For example, as shown in FIG. 13(b), by moving the entire control light pattern in the X direction by a distance corresponding to the spacing between the optical waveguide elements as shown by the arrow in FIG. 13(a), the addend is reduced to 3. It can be done. If the control light pattern is formed into linear patterns 120 and 121 as shown in FIG. 13(C), the accuracy of alignment will be significantly reduced. In this case as well, these control light patterns 12
0,121 in the X direction as shown by the arrow. In this way, according to this example, by spatially moving the predetermined control light pattern in one direction, the addend can be made variable. It is possible to do that.

Another embodiment of the present invention is shown in FIG. 14(a). this is,
This is another embodiment of the transmitter described in the previous section, and can also be used as a remainder calculator. The optical waveguide elements 130, 131, and 132 used in this embodiment are two-power, two-output elements as shown in FIG. In the case where there is no control light irradiation from the outside, the input guided light becomes the corresponding output as A-+C and B→D, and when there is control light irradiation, the input guided light becomes the corresponding output as A4D, B, and C. FIG. 14(a) shows the basic structure of an embodiment of the remainder arithmetic unit when the modulus is 3. As shown in FIGS. 14(b) to (e).

Control light is not irradiated ((b) in the same figure), or only elements 130 and 131 ((c) in the same figure), 130 and 132 ((d) in the same figure)', and 131 ((e) in the same figure) are used. ))
By irradiating the control light to (the intersection of the irradiated elements is shown by a solid line), the input light propagates through the paths shown by the arrows, respectively, )), + 1 (same figure (C)), +2 (same figure (d)
)) , X 2 ((e) in the same figure) can be executed.

FIG. 15(a) shows an example of an optical systolic arithmetic unit as yet another embodiment of the present invention. Systolic computation using light is a computation method that is suitable for multiplication of vectors and matrices. In this example, a plurality of two-manufactured two-output optical waveguide devices 140 to 142 (here, the number of elements is 2) shown in FIG.
(3 pieces to show an example of multiplication of a vector and a 2x2 matrix)
Install in parallel. The input/output characteristics are determined, for example, as shown in FIG. 15(b) for the input/output terminals A to D shown in the element 140, and the input The intensity of the corresponding control light a1 multiplied by a constant proportional to the input y to input terminal B (here O
) is taken out from the output terminal, the input vector It is coupled to the output terminal of the element at the output port, and the coupling is performed for a time corresponding to the interval of the synchronizing clock signal. Alternatively, the waveguide 1
Instead of 47 to 150, the above-mentioned delay can also be realized by extending an optical fiber outside the substrate 10 and attaching it externally.

Note that the above example uses an element that effectively performs light-to-light control by performing photoelectric conversion within an optical waveguide element, as shown in Figure 8 or Figure 1O (b). Of course, it is also possible to use an element that uses a physical phenomenon that allows input light to be directly controlled by control light, such as an element that uses a medium that has a laser effect due to optical excitation or a medium that has optical bistability.

[Effects] As described above, according to the present invention, an optical information processing device is configured by combining a plurality of optical waveguide elements whose input/output characteristics are controlled by control light irradiated from the outside. Compared to the conventional case where each element is directly controlled by an electrical control signal, the above-mentioned disadvantages (1) to (4)
By overcoming this, it is possible to process more complex information at higher speeds, and it is also possible to improve the insulation between control signals and input/output. Furthermore, in the present invention, an optical waveguide element
The information processing architecture can be simplified using the spatial arrangement of . As described above, the present invention introduces a revolutionary technology to information processing using light, and is expected to greatly contribute to related industrial fields.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the basic configuration of the optical information processing device of the present invention, FIG. 2 is a perspective view showing an example of a conventional optical information processing device, and FIGS. FIGS. 4(a) to 4(d) are perspective views showing the planar waveguide type optical waveguide element of the present invention; FIGS. 4(e) and 4(f) are perspective views showing the structure of the waveguide used; FIGS. Characteristic curve diagram for explaining the function of the optical waveguide device shown in (d), FIG. 5(a)
, (b) is a perspective view showing an optical waveguide element of variable absorption rate according to the present invention; FIGS. 6(a) to (C) are perspective views showing three examples of control light input forms according to the present invention; Figures (a) and (b) are diagrams schematically showing the optical waveguide device according to the present invention, Figures 8 (a) to (c) are input/output characteristic curve diagrams thereof, and Figure 9 is a diagram showing the two-man operation according to the present invention. A perspective view showing an example of a two-output optical waveguide element, FIG. 10(a) is a diagram showing an example of the configuration of a polynomial calculator as an example of the present invention, and FIG. FIG. 11 is a diagram showing a general-purpose optical crossbar switching device as an example of the present invention; FIG. 12 is an explanatory diagram of the operation of the two-power dual-blade leading waveguide device; FIGS. 13(a) to (C) are diagrams showing configuration examples of a cyclic permutation calculator as an example of the present invention, and FIGS. 14(a) to (e) are diagrams showing a permutation calculator as an example of the present invention. FIG. 15(a) is a diagram showing an example of the configuration of an optical systolic arithmetic unit as an example of the present invention. FIG. 15(b) is an input/output characteristic diagram of the optical waveguide element. It is. 31-1.31-2.31-3... Optically controlled optical waveguide element, 32-1.32-2.32-3... Optical waveguide (
), 33-1.33-2.33-3... control illumination light. Fig. 1 10 ---- Grave viper 31-1βl- for Ikkou Tomeri
2, 31-3---a control type 燵茥 Scream 32-1.32-
2.32-3---One optical equal wave path (plane) 33-1.33-
2.33-3--・Control sight Fig. 6 (a) (b) Fig. 8 system formation light Fig. 10 (0) Fig. 10 (b) 1-i-1 Ginr,') Certification

Claims (1)

[Claims] 1) An input waveguide, an output waveguide, and control for controlling the optical input from the input waveguide to output controlled output light from the output waveguide in response to external illumination light. By arranging a plurality of optical waveguide elements having a section on an optical waveguide substrate, and irradiating the control section of each of the plurality of optical waveguide elements with the external illumination light from outside the optical waveguide element, An optical information processing device characterized in that guided light propagating between the plurality of optical waveguide elements is controlled. 2) Optical information according to claim 1, characterized in that an optical delay element is inserted between the optical waveguide elements to delay the transmission time of the guided light between the optical waveguide elements. Processing equipment. 3) The optical information processing device according to claim 3, wherein the optical delay element is an optical fiber. 4) The optical information processing device according to claim 2, wherein the plurality of optical waveguide elements are arranged so as to perform optical systolic calculations. 5) Claim 2, characterized in that the plurality of optical waveguide elements are arranged so as to perform polynomial calculations.
The optical information processing device described in Section 1. 6) The optical waveguide element has first and second waveguide light input terminals and first and second waveguide light output terminals, and when control light is not irradiated from outside the optical waveguide element, the first and second waveguide light input terminals
Guided waveguide light incident on the input terminal is guided to the first output terminal, guided waveguide light incident on the second input terminal is guided to the second output terminal, and when a predetermined control light is irradiated, the first input The optical waveguide elements are arranged in a lattice, and the waveguide elements are arranged in a lattice, and the waveguide light incident on the terminal is guided to a second output terminal, and the waveguide light incident on the second input terminal is guided to the first output terminal. For the elements other than the outer end, each first output terminal is coupled to the first input terminal of the element adjacent to the right, the second output terminal is coupled to the second input terminal of the element adjacent below, and the left edge of the grid The first element of
receiving light input to the device through an input terminal, and taking out the output of the device from a second output terminal of the element at the lower end of the grating;
The second input terminal of the element at the upper end of the grid is a non-input terminal, the first output terminal of the element at the right end of the grid is a non-reflection end, and input light information from a plurality of devices is inputted from a specific output terminal of each device that requires it. The optical information processing device according to claim 1, wherein the optical information processing device is adapted to be taken out. 7) A plurality of external illumination light patterns that illuminate diagonally adjacent optical waveguide elements among the plurality of optical waveguide elements are spatially directed in one direction along the main surface of the substrate while maintaining the pattern shape. 7. The optical information processing apparatus according to claim 6, wherein a cyclic permutation operation is realized by moving to . 8) The device input light corresponds to a remainder summand or subtractor in an adder or subtracter for optical remainder calculation, and the output of the device is a sum or a difference by controlling the addend or subtractor by the external illumination light. The optical information processing apparatus according to claim 7, characterized in that the optical information processing apparatus corresponds to the above. 9) The optical information processing device according to claim 7 or 8, wherein the optical pattern is a linear pattern.