JPH03268352A - Optical integrated circuit - Google Patents

Abstract

PURPOSE:To make an optical integrated circuit to be applied easily to a neural network device by providing a means which makes input light to incident to an optical switching element from the outside and another means which makes the output light of the optical switching element to incident to the photoreceptor element of another device to each of a plurality of specific semiconductor optical devices. CONSTITUTION:The semiconductor optical switching element S of each semicon ductor optical device U is connected with a semiconductor photoreceptor element R in parallel or series and with a required power source 4 and input light is made incident to the element S from the outside through an input light incident means. The output light of the element S is made incident to the semiconductor photoreceptor element R of another semiconductor optical device through an output light incident means. Then, the element R is set to a state where the element R has a low end-to-end resistance only. Accordingly, the element S can be turned off when, for example, the element R is connected with the ele ment S in parallel and the optical switching element S of the another semicon ductor optical device is on and emits its output light. Therefore, this optical integrated circuit can be applied easily to a neural network device.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to an optical integrated circuit that can be applied to a neural network device.

[Conventional technology]

Conventionally, optical integrated circuits that can be applied to neural network devices have been proposed, but they have not been put into practical use due to their complexity and large size. Therefore, the present invention aims to propose a novel optical integrated circuit that can be easily applied to a neural network device as a practical device.

[Means to solve the problem]

The optical integrated circuit according to the first invention of the present application includes: (1) a semiconductor optical switch element arranged one-dimensionally or two-dimensionally and having a memory function; or a plurality of semiconductor optical devices having semiconductor light-receiving elements connected in series, and (1) Input light input for inputting light from the outside into the semiconductor optical switch element of the semiconductor optical device for each of the plurality of semiconductor optical devices. (1) output light obtained from a semiconductor optical switch element of the first semiconductor optical device with respect to one semiconductor optical device among the plurality of semiconductor optical devices and other semiconductor optical devices arranged around it; output light input means for inputting the output light into some or all of the semiconductor light receiving elements in the other semiconductor optical device. Further, the optical integrated circuit according to the second invention of the present application is the optical integrated circuit according to the first invention of the present application, in which each of a part or all of the semiconductor optical devices among the plurality of semiconductor optical devices is It has another output light input means for making a part of the output light obtained from the semiconductor optical switch element enter the semiconductor light receiving element of its own semiconductor optical device as bias light.

[Action/effect]

According to the optical integrated circuit according to the first invention of the present application, one semiconductor optical device among a plurality of semiconductor optical devices (generally referred to as U,
) and other semiconductor optical devices (generally referred to as U) arranged around it, the semiconductor optical switch elements of each semiconductor optical device are connected in parallel or in series with the semiconductor photodetector. If input light is made to enter the semiconductor optical switch element of one semiconductor optical device U8 from the outside through the input light input means while the semiconductor optical device U8 is connected to a required power source, The semiconductor optical switch element of the - semiconductor device @Ua can be brought into an on state from which light emission is obtained as output light, and the output light obtained from the semiconductor optical switch element of the - semiconductor device @U can be turned on. is transmitted to some or all of the semiconductor optical devices (generally referred to as U) in other semiconductor optical devices U through the output light input means.
It is possible to make the semiconductor light receiving element of the semiconductor device IU' have a low resistance at both ends. Therefore, when the semiconductor light receiving element of each semiconductor optical device is connected in parallel with the semiconductor optical switch element, the semiconductor optical switch element of the semiconductor optical device U' is in an on state emitting output light. Therefore, when input light enters the semiconductor optical switch element of the semiconductor optical device U from a state in which a relatively large current is flowing through the semiconductor optical switch element,
The current that has so far flowed through the semiconductor optical switch element of the semiconductor device itu flows into the semiconductor light receiving element of the semiconductor device stu,', and thus the semiconductor optical device U. The current that has been flowing through the semiconductor optical switch element of the semiconductor optical device U' becomes a sufficiently small value or stops flowing, and as a result, the semiconductor optical switch element of the semiconductor optical device U' changes from the on state to the off state where no output light is emitted. can be put into a state. Furthermore, when the semiconductor light receiving element of each semiconductor optical VC device is connected in parallel with the semiconductor optical switch element, the semiconductor optical switch element of the semiconductor optical device U' is in an off state in which it does not emit output light, and therefore Even if input light enters the semiconductor optical switch element of the semiconductor optical device Ua from a state where the current is flowing at a sufficiently small value or is almost not flowing through the semiconductor optical switch element, the semiconductor optical device u,'
It is possible to keep the semiconductor optical switch device in an off state. Further, when the semiconductor light receiving element of each semiconductor optical device is connected in series with the semiconductor optical switch element, the semiconductor optical switch element of the semiconductor optical device U' is in an on state emitting output light, From a state in which a relatively large current is flowing through the semiconductor optical switch element, input light enters the semiconductor optical switch element of the semiconductor optical device Ua, causing current to flow through the semiconductor optical switch element of the semiconductor device @Ub. Since the current flows at a larger value than the current current, the output light from the semiconductor optical switch element of the semiconductor optical device U' can be obtained with a lower intensity than that which has been obtained up to now. Furthermore, in the case where the semiconductor light receiving element of each semiconductor optical device is connected in series with the semiconductor optical switch element, the semiconductor optical switch element of the semiconductor optical device U is in an off state in which it does not emit output light, so that Even if input light is incident on the semiconductor optical switch element of semiconductor device aU when the current is flowing at a sufficiently small value or is almost not flowing through the semiconductor optical switch element, the semiconductor optical switch element of semiconductor optical device u' It can be kept in the off state. From the above, according to the optical integrated circuit according to the first invention of the present application, a plurality of semiconductor optical devices can be put into practical use as a neural network device in a manner that corresponds to a processor corresponding to a neuron in a neural network. It can be easily applied as Further, the optical integrated circuit according to the second invention of the present application is the optical integrated circuit according to the first invention of the present application, in which each of a part or all of the semiconductor optical devices among the plurality of semiconductor optical devices is The light according to the first invention of the present application, except that it has another output light input means for making a part of the output light obtained from the semiconductor optical switch element enter the semiconductor light receiving element of its own semiconductor optical device as bias light. It has the same configuration as an integrated circuit, and is a semiconductor device @(
When the semiconductor optical pinch element of the semiconductor optical device U' is in an on state emitting output light, a part of the output light from the semiconductor optical pinch element of the semiconductor optical device U' is transmitted to the semiconductor via another output light input means. Since the bias light can be incident on the semiconductor light-receiving element of the optical device U', the same operation and effect as in the case of the optical integrated circuit according to the first invention of the present application can be obtained, and in this case, Regarding the optical integrated circuit according to the first aspect of the present application, the operation when input light enters the semiconductor switch element of the semiconductor optical device U from the ON state in which the semiconductor optical switch element of the semiconductor device MUb described above emits output light. can be carried out effectively. [Embodiment] Next, an embodiment of the optical integrated circuit according to the present invention will be described with reference to FIGS. 1 and 2. The optical integrated circuit according to the present invention shown in FIGS. 1 and 2 has the following configuration. That is, it has a substrate 1 that is transparent to light obtained from a semiconductor optical switch element of a semiconductor optical device, which will be described later, and a plurality of semiconductor optical devices are arranged on a first main surface 1a of the substrate 1. U represents a relationship in which one semiconductor optical device and six other semiconductor optical devices are arranged at six vertices of a hexagon centered on the center point where the first semiconductor optical device is arranged. It is arranged so that it can be obtained. In this case, each semiconductor optical device U includes a semiconductor optical switch element S having a memory function and the semiconductor optical switch element S.
It has semiconductor light-receiving elements R disposed in an annular shape in close proximity to the semiconductor light-receiving elements R and connected in parallel as shown in FIG. 3 or in series as shown in FIG. In this case, as the semiconductor optical switch element S, a known optical thyristor, for example, a pnpn type optical thyristor, which has a current-voltage characteristic exhibiting a negative characteristic as shown in FIG. 5, can be used. In addition, as the semiconductor light receiving element S, the well-known p
In addition to using an npn type optical thyristor, a known photodiode or phototransistor may be used. Furthermore, a window W is left on the second main surface 1b facing the first main surface 1a of the substrate 1, through which the semiconductor optical switch element S of each semiconductor device LTU is exposed to the outside through the thickness of the substrate 1. The reflective film 2 is formed as shown in FIG. The above is the configuration of the embodiment of the optical integrated circuit according to the present invention. According to such an optical integrated circuit according to the present invention, one semiconductor optical device among a plurality of semiconductor optical devices U (generally referred to as Ua
) and other semiconductor optical devices (generally referred to as U) arranged around it, the semiconductor optical switch element S of each semiconductor optical device U is replaced by the semiconductor light receiving element R.
and are connected in parallel as shown in Figure 3 or in series as shown in Figure 4, and the load resistor 3 is connected as required.
Input light L1 is input from the outside on the main surface 1b side of the substrate 1 to the semiconductor optical switch element S of one semiconductor optical device U8 while the input light L1 is connected to the required electric current m4 through the window W. , the maximum voltage extreme value of the current-voltage characteristic of the semiconductor optical switch element S of the first semiconductor optical device Ua becomes so small that it does not cross the load line of the semiconductor optical switch element S. , the semiconductor optical switch element S can be brought into an on state from which light emission is obtained as output light L2, and the output light L2 obtained from the semiconductor optical switch element of the first semiconductor optical device U can be Via the output light input means of the reflective film 2, it is transmitted to the semiconductor light-receiving element R of a semiconductor device If (generally referred to as U') in a part or all (a part in the figure) of another semiconductor device IUb. The semiconductor light-receiving element R of the semiconductor device IU' can be made to have only a low resistance at both ends. Therefore, when the semiconductor light receiving element R of each semiconductor device 11LI is connected in parallel with the semiconductor optical switch element S as shown in FIG. The semiconductor optical device U is in the on state in which it emits light, and therefore a relatively large current flows through the semiconductor optical switch element S (operating at the operating point B in FIG. 4). As a result of the input light 1 being incident on the semiconductor optical switch element S of the semiconductor optical device U', the current flowing through the semiconductor optical switch element of the semiconductor optical device U' is transferred to the semiconductor light receiving element R1 of the semiconductor optical device U': ! Therefore, the current that has been flowing in the semiconductor optical switch element S of the semiconductor device mu,' becomes a sufficiently small value or stops flowing, and therefore the semiconductor optical device U
’ from the on state to the output light L
2 can be placed in an off state (operating at operating point A in FIG. 5) in which no light is emitted. Furthermore, when the semiconductor light receiving element R of each semiconductor device MU is connected in parallel with the semiconductor optical switch element S as shown in FIG. 3, the light L2 output by the semiconductor optical switch element S of the semiconductor optical device U' is The semiconductor optical switch element S is in an off state in which no light is emitted, and therefore a sufficiently small current or almost no current is flowing through the semiconductor optical switch element S (operating at operating point A in Fig. 5). Even if the input light L1 is incident on the semiconductor optical switch element S of the WIUa, the semiconductor optical switch element S of the semiconductor optical device U' can be kept in the off state. Further, when the semiconductor light receiving element R of each semiconductor optical device U is connected in series with the semiconductor optical switch element S as shown in FIG. 4, the semiconductor optical switch element S of the semiconductor optical device U' receives the output light b L2. In the on state in which the light is emitted, the operating point B is shown in Fig. 5.
Therefore, when the input light L1 enters the semiconductor optical switch element S of the semiconductor optical device U8 from a state in which a current is flowing at a relatively large value through the semiconductor optical switch element S, , the current flows through the semiconductor optical switch element S of the semiconductor device IU' at a value larger than that previously flowing, so that the output light L2 from the semiconductor optical switch element of the semiconductor optical device Ub' has not been obtained until now. obtained with higher strength than Furthermore, when the semiconductor light receiving element R of each semiconductor optical device U is connected in series with the semiconductor optical switch element S as shown in FIG. It is in the off state M where L2 is not emitted (operating at operating point B in Fig. 5), and therefore the semiconductor optical switch element S is in a state where the current is flowing at a sufficiently small value or almost no current. Even if the input light L1 is incident on the semiconductor optical switch element S of the semiconductor optical device U, the semiconductor optical switch element S of the semiconductor device tU' can be kept in the off state. From the above, according to the optical integrated circuit according to the present invention shown in FIGS. 1 and 2, in a neural network device, a plurality of semiconductor devices MU are made to correspond to processors corresponding to neurons in a neural network. It can be easily applied as something that can be put into practical use. Note that the above description has only shown one example of the present invention, and detailed description of the drawings is omitted, but for each of some or all of the semiconductor optical devices Ub among the plurality of semiconductor optical devices U, the semiconductor device WU, Except for having another output light input means for making a part of the output light obtained from the semiconductor optical switch element S of the semiconductor optical device U enter the semiconductor light receiving element R of the own semiconductor optical device U as bias light. It may also have a configuration similar to the optical integrated circuit according to the present invention described above in FIG. 2, and in that case, the semiconductor optical device Ub
When the semiconductor optical switch element S of ' is in the ON state emitting output light, a part of the output light from the semiconductor optical switch element S of the semiconductor device @U ' is transmitted to another output light input means. Through the semiconductor optical device U. Since the bias light can be incident on the semiconductor light-receiving element R of , it is possible to obtain the same operation and effect as in the case of the optical integrated circuit according to the present invention described above in FIGS. 1 and 2, and in this case, , from the on state in which the semiconductor optical switch element S of the semiconductor optical device U described above for the optical integrated circuit described above in FIGS. 1 and 2 emits output light,
The operation when input light is incident on the semiconductor optical switch element S of the semiconductor device ILIa can be performed effectively. Further, as shown in FIG. 6, an anti-reflection film 4 is provided inside the window W, and the semiconductor optical switch element S of the semiconductor optical device Ua is
It is also possible to prevent the output light from entering the own semiconductor optical device tJa or other undesired semiconductor optical devices ub unnecessarily. Furthermore, in the above description, the reflection I! as the output light input means! Although we have described the case where i12 is formed on the flat main surface 1b of the substrate 1 and they form a flat mirror, the output light input means may be a convex mirror as shown in FIG. The output light L from the semiconductor optical switch element S of the semiconductor layer element Ua may be a concave mirror as shown in FIG.
2 is the semiconductor light receiving element R of the semiconductor optical device Ub at a predetermined position.
Alternatively, the output light L2 may be made to enter the semiconductor optical device Ub at a desired position with high or low intensity. Various other modifications and changes may be made without departing from the spirit of the invention.

[Brief explanation of drawings]

1 and 2 are a schematic plan view showing an embodiment of an optical integrated circuit according to the present invention, and a sectional view taken along the line 2--2 thereof. 3 and 4 are diagrams showing the electrical connection relationship between the semiconductor optical switch element and the semiconductor light receiving element in each semiconductor optical device of the optical integrated circuit according to the present invention shown in FIGS. 1 and 2. FIG. FIG. 5 is a diagram showing current-voltage characteristics of an optical thyristor that can be used as a semiconductor optical switch element in each semiconductor optical device of the optical integrated circuit according to the present invention shown in FIGS. 1 and 2. FIG. 6, 7, and 8 are partial cross-sectional views showing other embodiments of the optical integrated circuit according to the present invention.

Claims (1)

[Scope of Claims] [Claim 1] A semiconductor optical switch element arranged one-dimensionally or two-dimensionally and having a memory function, and a semiconductor optical switch element arranged close to the semiconductor optical switch element and electrically parallel or a plurality of semiconductor optical devices having semiconductor light receiving elements connected in series; and, for each of the plurality of semiconductor optical devices, input light input means for inputting input light from the outside into a semiconductor optical switch element of the semiconductor optical device; , regarding one semiconductor optical device among the plurality of semiconductor optical devices and other semiconductor optical devices arranged around it, the output light obtained from the semiconductor optical switch element of the one semiconductor optical device is 1. An optical integrated circuit comprising output light input means for inputting output light to some or all semiconductor light receiving elements of another semiconductor optical device. 2. A semiconductor optical switch element arranged one-dimensionally or two-dimensionally and having a memory function, and a semiconductor disposed close to the semiconductor optical switch element and electrically connected in parallel or in series. a plurality of semiconductor optical devices having a light receiving element; and for each of the plurality of semiconductor optical devices, input light input means for inputting input light from the outside into a semiconductor optical switch element of the semiconductor optical device; Regarding one semiconductor optical device in the apparatus and other semiconductor optical devices arranged around it, the output light obtained from the semiconductor optical switch element of the one semiconductor optical device is transferred to the other semiconductor optical device. An output light input means for making the light incident on some or all of the semiconductor light receiving elements; and an output obtained from the semiconductor optical switch element of the semiconductor optical device for each of the some or all of the semiconductor optical devices among the plurality of semiconductor optical devices. 1. An optical integrated circuit comprising another output light input means for inputting a part of the light to a semiconductor light receiving element of its own semiconductor optical device. 3. The optical integrated circuit according to claim 1 or 2, wherein the plurality of semiconductor optical devices are arranged on a first main surface of a substrate that is transparent to the output light. An optical integrated circuit, wherein the output light input means is provided on a second main surface of the substrate opposite to the first main surface.