JPH0220833A - Optical arithmetic unit - Google Patents

Abstract

PURPOSE:To perform logical arithmetic operations in parallel at a high speed by deflecting light emitted by the light source of a 1st plane and light emitted by a 2nd plane and driving optical function elements of the 1st and 2nd planes. CONSTITUTION:Data inputted to the unit is controlled by driving devices 4 and 5. Light emitted by an optical threshold element array 1 is deflected by an optical deflecting element and converged on an optical threshold element array 2. At this time, an output-side optical threshold element emits light only at the part where the light from >=1 optical threshold element is incident when the threshold level is at L or the part where light beams from two optical threshold elements overlap with each other when at H to generate 1 when the light is emitted and 0 when not, thereby performing desired logical arithmetic operations. The light emitted by the optical threshold element is incident reversely on the optical deflecting element and converged on the optical threshold element array 1 similarly to perform the plural arithmetic operations like a catch ball. Consequently, the logical arithmetic operations are performed in parallel at a high speed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an optical arithmetic device that performs logical operations in parallel and at high speed using light.

(Prior art and its problems) Light has a spatial expanse and its physical properties do not interfere with each other, so operations using light have excellent parallelism. As means for modulating light, amplitude, phase, frequency, polarization, etc. can be considered, and spatial light modulators are being developed.

However, many of the conventional optical calculation methods aimed at speeding up are not suitable for parallel calculations, and many of them are aimed at parallelization and require complex coding before calculation, making them impractical. Regarding methods aimed at increasing speed, there have been reports that it was possible to perform picosecond calculations using optical semiconductor devices as a single device, but there has been no systematic study and the device has not yet been developed. On the other hand, methods aimed at parallelization are, for example, published in magazines, Optical Engineering
) Vol. 26, 1987, pp. 28-33, "Binary Logic Using Spatial Filtering (Bina
ry logic by spatial filter
mentioned in the month of ring. This method uses a spatial light modulator to control the direction of polarization, and currently no device has been found that can perform this task at high speed.

(Objective of the Invention) An object of the present invention is to provide an optical operation method and apparatus for executing logical operations in parallel and at high speed using optical interconnection.

(Means for Solving the Problems) The optical processing device of the present invention includes a first surface in which a plurality of optical functional elements each having a light emitting section and a light receiving section arranged adjacent to each other are arranged, and each light emitting section on the first surface emits light. FIG. 2 shows the first surface arranged facing the first surface so that the light emitted from each light-emitting section enters the light-receiving section, and the light emitted from each light-emitting section enters each light-receiving section on the first surface; and a beam deflecting means placed between the first surface and the second surface for deflecting a beam of light emitted from the light source of the first surface and a beam of light emitted from the second surface;
It is characterized by comprising a la control means for driving the optical functional element on the surface.

(Operation) The operation of this invention will be explained with reference to FIG. 2. FIG. 2 is a diagram showing the relationship between input data and an input surface. Two-dimensional binary input data 101 (a, b, c, d,
e, 0 and the inverted data of those input data (a
, b, c, d, e, and 0 are arranged in an array to form an input surface 102. Prepare two sets of input surfaces like this,
As shown in FIG. 3, the human output surfaces 201 and 202 are placed facing each other. The light emitted from the light emitting part of the input/output surface 201 is deflected by the optical deflection element 203 and
The light is focused on the second light receiving section. Furthermore, the light emitted from the light emitting section of the input/output surface 202 is deflected by the optical deflection element 203 and focused on the light receiving section of the input/output surface 201 .

FIG. 4 shows an example of the relationship between data and the light emitting section. Figure 4 (
As shown in a), one set of calculations is performed using four light emitting parts, input data A is displayed in the upper right corner of the figure, its inverted data A is displayed in the upper left corner, manual data B is displayed in the lower right corner, and its inverted data B is displayed in the lower left corner of the figure. It is expressed by the light emitting part of. The light emitted from these light emitting parts is deflected by a light deflection element and focused on a light receiving part having a structure as shown in FIG. 4(b).

By electrically binarizing the light detected by the light receiving section, or by configuring the light receiving section with an optical threshold element,
The received light signal can be binarized.

FIG. 5 shows the structure of the human power side of the optical threshold element, the optical deflection element, and the output side of the optical threshold element. (a) shows the structure of the light emitting part, (b) shows the structure of the light deflection element, and (c) shows the structure of the light receiving part. The light emitting part is 11.12.21.22, and each element of the optical deflection element is aa, ab, ba, bb,
Let the light receiving parts be c and d. At this time, light source 1 of the optical threshold element
1.12.21.22 are input data A and A, respectively.
,B.

B, and the light receiving parts c and d each have output data 0.
．． Corresponds to 1. For example, if the optical deflection element is manufactured so that the light emitted from 12.22 is focused on d and the light emitted from 11.21 is focused on C, an AND operation is performed. Table 1 shows the connection slam of the optical deflection element and the binarization level of the optical threshold element, which determine the relationship between human power and output for 14 types of logical operations. L represents the level at which light is emitted when the light equivalent to one or more light threshold elements is incident, and H represents the level at which light is emitted when the amount of light from two light threshold elements is incident. In the table, ○
A mark indicates a relationship that is connected to each other, and a no mark indicates a relationship that is not connected.

Further, in the table, 0 and 1 in the left column indicate calculation results for human data. For example, in the case of AND operation, 11.
The light emitted from 21 is aa and ba, respectively, to C, and the light emitted from 12.22 is ab, respectively.

Branched to d by bb. The light receiving part C binarizes the light equivalent to one optical threshold element, and the light receiving part d binarizes the light equivalent to two optical threshold elements.Therefore, if a light deflection element corresponding to each operation is created, the light for executing the own operation is generated. A computing device is obtained.

(Example) The present invention will be explained in detail below.

FIG. 1 is a perspective view showing an example of an embodiment for realizing the optical arithmetic device of the present invention. This optical processing device is a two-dimensional array of optical bistable elements such as VSTEP and laser, or optical threshold elements that combine photodetectors and electronic circuits, which switch and emit light when a certain level of light is incident. In an optical processing device having a configuration higher than that of a device consisting of an optical threshold element array 1.2, an optical deflection element 3 such as a hologram, and a circuit for applying a voltage to the optical threshold element, the data input to the device is Controlled by devices 4,5. The light emitted from the optical threshold element array is deflected by the optical deflection element according to the branching rules in Table 1, and is focused on the optical threshold element array 2. At this time, if the threshold level is L, one or more light threshold elements on the input side
In the case of , the output-side optical threshold element emits light only in the portion where the light from the two optical threshold elements overlap. 1 if it emits light,
By setting the value to 0 when the value is not used, a desired logical operation can be executed. The output of the optical threshold element is equal to the input light for the next operation, and these operations can be cascaded. The light emitted from the optical threshold element is reversely incident on the optical deflection element, and is similarly focused on the optical threshold element array 1, like a catch pole, so that a plurality of logical operations can be executed.

FIG. 6 shows the structure of VSTEP. This element is an AI
It has a layered structure of GaAs and GaAs, and when a voltage is applied between the anode and cathode and light of a certain level or higher is applied thereto and absorbed, the generated current is amplified by a positive feedback effect and switched, causing light emission. do. The amount of incident light required for switching can be controlled by the applied voltage, and can be used as a light threshold element.

A hologram used as a light deflection element can be produced using a computer generated hologram technique. Since a hologram is an interference pattern between a reference beam and an object beam, the pattern can be determined as follows. Since the light emitted from the optical threshold element on the input side and the light diffracted by the hologram can be regarded as spherical waves, the interference pattern of these waves can be expressed as follows: the amplitude per unit distance of the spherical wave is a1, the wave number is k,
Letting r be the distance from the element to each point on the hologram, it is expressed by the following equation.

A hologram is obtained by binarizing the pattern expressed by equation (1) using the average value and drawing it on a dry plate using an electron beam or the like.

Note that the tip optical element is not limited to a hologram, but can also be represented by a prism or the like.

(Effects of the Invention) As detailed above, by using the optical arithmetic device of the present invention, logical operations can be executed in parallel and at high speed.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of the optical calculation method of the present invention;
FIG. 2 is a diagram showing the relationship between input data and the input surface, and is a diagram showing the structure of each element, and FIG. 6 is a diagram showing the structure of VSTEP. In the figure, 1.2... Optical threshold element array, 3.203... Optical deflection element, 4°5... Drive device, 101... Input data, 102... Input surface, 201, 202 ...Input/output surface.

Claims (1)

[Claims] A first surface in which a plurality of optical functional elements are arranged in which a light emitting part and a light receiving part are arranged adjacent to each other, and light emitted from each light emitting part on the first surface enters each light receiving part and is emitted from each light emitting part. a second surface disposed facing the first surface so that light enters each light receiving portion of the first surface; and a first surface disposed between the first surface and the second surface. A beam deflecting means for deflecting a beam of light emitted from the light source on the surface and a beam of light emitted from the second surface, and a set of control means for driving the optical functional elements on the first surface and the second surface. An optical computing device characterized by: