KR19990012823A - Optical logic device and logic operation method using same - Google Patents

Abstract

Disclosed are an optical logic device using an actuated mirror array (AMA) device and a logic operation method using the same. The first logic input unit includes a first AMA element made of mirror pixels deformed to modulate a light beam generated from a light source by an applied electrical signal, and a first light receiving element for applying an electrical signal to the first AMA element. Include. The second logic input unit includes a second AMA element made of mirror pixels deformed to modulate the light beam by an applied electrical signal, and a second light receiving element for applying an electrical signal to the second AMA element. The optical path changing member changes the optical path so that light rays generated from the light source are sequentially modulated by the first AMA element and the second AMA element. The projection lens projects light rays that sequentially pass through the first and second logic input units to a logic output unit. Independent logic operations may be performed for each mirror pixel of the AMA device, and thus a large amount of data may be processed simultaneously.

Description

Optical logic device and logic operation method using same

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical logic element and a logic operation method using the same. More specifically, a large amount of logic operation is simultaneously performed using an Actuated Mirror Array (AMA) element. The present invention relates to an optical logic device that can be performed and a logic operation method using the same.

In general, spatial light modulators, which are devices for projecting optical energy onto a screen, can be applied to various fields such as optical communication, image processing, and information display devices. Typically, such devices are classified into a direct-view image display device and a projection-type image display device according to a method of displaying optical energy on a screen.

An example of a direct-view image display device is a CRT (Cathode Ray Tube). The CRT device is called a CRT, which has excellent image quality but increases in weight and volume as the screen is enlarged, leading to an increase in manufacturing cost. There is.

Projection type image display apparatuses include liquid crystal displays (hereinafter referred to as LCDs), deformable mirror devices (hereinafter referred to as DMDs), and actuated mirror arrays (hereinafter referred to as AMAs). And the like). Such projection image display devices can be further divided into two groups according to their optical characteristics. That is, devices such as LCDs can be classified as transmissive spatial light modulators, while DMD and AMA can be classified as reflective spatial light modulators.

Transmission optical modulators, such as LCDs, have a very simple optical structure, which makes them thinner, lighter in weight, and smaller in volume. However, due to the polarity of the light, the light efficiency is low, there is a problem inherent in the liquid crystal material, for example, there is a disadvantage that the response speed is slow and the inside is easy to overheat. In addition, the maximum light efficiency of existing transmission light modulators is limited to a range of 1-2% and requires dark room conditions to provide acceptable display quality.

Optical modulators such as DMD and AMA have been developed to solve the problems of the aforementioned LCD type optical modulators.

DMD shows a relatively good light efficiency of about 5%, but serious fatigue problems are caused by the hinge structure employed in the DMD. In addition, there is a disadvantage that a very complicated and expensive driving circuit is required.

In the AMA, each of the mirrors installed therein reflects light incident from the light source at a predetermined angle, and the reflected light is projected on the screen through an aperture such as a slit or a pinhole. It is a device that can adjust the speed of light to form an image. Therefore, the structure and operation principle are simple, and high light efficiency (more than 10% light efficiency) can be obtained compared with LCD and DMD. In addition, contrast can be improved to obtain a bright and clear image.

Each actuator of the AMA generates a deformation in accordance with the electric field generated by the applied electric image signal and the bias voltage. As the actuator deforms, each of the mirrors mounted thereon is tilted. Accordingly, the inclined mirrors reflect light incident from the light source at a predetermined angle to form an image on the screen. Piezoelectric materials such as PZT (Pb (Zr, Ti) O ₃ ), or PLZT ((Pb, La) (Zr, Ti) O ₃ ) are used as actuators for driving the respective mirrors. The actuator may also be configured as a warping material such as PMN (Pb (Mg, Nb) O ₃ ).

These AMAs are largely divided into bulk type and thin film type. Bulk AMA is disclosed in US Pat. No. 5,085,497 to Gregory Um et al. The bulk AMA is made by thinly cutting a multilayer ceramic to mount a ceramic wafer having a metal electrode formed therein in an active matrix in which a transistor is built, and then processing by a sawing method and installing a mirror thereon. However, bulk AMA requires very high precision in design and manufacture, and has a disadvantage of slow response of the strained layer. Accordingly, recently, a thin film type AMA that can be manufactured using a semiconductor manufacturing process has been developed. For example, such a thin film type AMA is disclosed in Korean Patent Application No. 95-13353 (name of the invention: a method for manufacturing an optical path control device), filed by the applicant with the Korean Patent Office.

Thin film type AMA is manufactured using thin film processes well known in the semiconductor industry. Thin film type AMA was developed to transmit enough light on the screen to display a digital image at high brightness and high contrast under normal room lighting conditions. Thin film type AMA is a reflective light modulator using thin film piezo-electric actuators with respect to microscopic mirrors of 100 μm-100 μm. Thin-film AMAs have been developed to have a high degree of inclination for high contrast, sufficient light efficiency for high brightness, and uniformity of large-scale integration over 300,000 pixels of a single panel mirror. The thin-film AMA consists of panels of 640x480 pixels, each representing red, green and blue. The pixels are designed as cantilever structures to maximize the mirror surface area to increase light efficiency. The cantilever structure largely includes an active matrix to which an image signal voltage is applied and a cantilever mirror operated by an applied signal voltage.

On the other hand, in recent years, a study on an optical logic device for forming a logic device made by attaching an input terminal and an output terminal to a single device to perform an operation as a logic circuit by using an information transmission method using an optical fiber Is actively underway. Here, the logic circuit refers to a circuit used to perform arithmetic by logical algebra, which represents a logical relation of various conditions as a logical symbol and deals with algebraic operations in the form of an expression.

It is a first object of the present invention to provide an optical logic device capable of simultaneously performing a large amount of logic operations using an AMA device.

A second object of the present invention is to provide a logic operation method using the optical logic element.

1 is a schematic diagram showing an optical logic device using an actuated mirror array device according to an embodiment of the present invention.

FIG. 2 is a logic table showing an exclusive OR operation by the optical logic element shown in FIG. 1.

Explanation of symbols for main parts of the drawings

100: optical logic element 112: light source

114: source stop 115: optical path change member

116a, 116b: first and second field lenses

118a, 118b: first and second AMA elements

120a and 120b: first and second light receiving elements

122a, 122b: first and second optical fiber bundles

125a, 125b: first and second logic inputs

126: projection stop 128: projection lens

130: logic output unit

In order to achieve the first object of the present invention described above, the present invention, a light source for generating a light ray; A first logic input unit comprising a first AMA element comprising mirror pixels deformed to modulate the light beam by an applied electrical signal, and a first light receiving element for applying an electrical signal to the first AMA element; A second logic input unit comprising a second AMA element made of mirror pixels deformed to modulate the light beam by an applied electrical signal, and a second light receiving element for applying an electrical signal to the second AMA element; Optical path changing means for changing an optical path such that light rays generated from the light source are sequentially modulated by the first AMA element and the second AMA element; And a projection lens for projecting light rays passing through the first and second logic input units sequentially to a logic output unit.

The present invention also provides an AMA device including an active matrix to which an electrical signal is applied, and actuators operated by receiving an electrical signal from the active matrix; And an array of light receiving elements connected to the active matrix so as to correspond to respective actuators of the AMA device, and converting light transmitted from the optical fiber bundle into an electrical signal to apply the electrical signal to the active matrix. A light modulator is provided.

In order to achieve the above-described second object of the present invention, the present invention provides a first logic including a first AMA element and a first light receiving element made up of a plurality of mirror pixels through light path changing means for light rays generated from a light source. Irradiating an input unit; Deforming mirror pixels of the first AMA device by applying an electrical signal from the first light receiving device to the first AMA device; Irradiating, by the optical path changing means, light rays reflected from each mirror pixel of the first AMA element to a second logic input unit including a second AMA element consisting of a plurality of mirror pixels and a second light receiving element; Deforming mirror pixels of the second AMA device by applying an electrical signal from the second light receiving device to the second AMA device; And performing a logic operation by projecting light rays reflected from each mirror pixel of the AMA element to a logic output unit through a projection lens.

As described above, according to the present invention, two logic input units are configured by using an optical modulation device comprising an AMA element, a light receiving element for applying an electrical signal to the AMA element, and an optical fiber bundle for applying light to the light receiving element. do. In addition, a half mirror coated prism is used to direct the light rays generated from the light source through the two logic inputs sequentially to a logic output including an optical fiber bundle.

According to a preferred embodiment of the present invention, the optical axis of the light source and the source stop is deviated from the optical axis of the first logic input unit, and the optical axis of the projection stop and the projection lens is coincident with the optical axis of the second logic input unit, thereby exclusive. OR operation). For example, when the mirror of the AMA device is tilted as state 1 and the non-tilted state as state 0, when the states of the first logic input unit and the second logic input unit are different from each other, that is, the first and The state of the output becomes 1 when the AMA mirror pixel of any of the second logic input units is tilted.

Therefore, a micro optical logic gate can be manufactured using the AMA device. In addition, since independent logic operations may be performed for each mirror pixel of the AMA device, a large amount of data may be processed simultaneously.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic diagram showing an optical logic device using an AMA device according to an embodiment of the present invention.

Referring to FIG. 1, the optical logic device 100 includes a light source 112, a source stop 114, an optical path changing member 115, first and second field lenses 116a and 116b, and first and second AMAs. Elements 118a and 118b, first and second light receiving elements 120a and 120b, first and second optical fiber bundles 122a and 122b, first and second logic inputs 125a and 125b, and projection stops ( 126, projection lens 128, and logic output 130.

The light source 112 is preferably a light emitting diode (LED). The light emitting diode 112 is a device that emits light when a current flows, and when a small number of carriers are injected into a pn junction of a semiconductor by flowing a current, the energy possessed when the electrons are excited at a higher energy level and then returned to a stable state is light. A device that emits as electromagnetic waves with a wavelength band of.

The source stop 114 is an optically opaque member and has an aperture formed to pass light rays. The source stop 114 determines the amount of light that forms the image. According to a preferred embodiment of the present invention, the optical axes of the light source 112 and the source stop 114 do not coincide with the optical axes of the first logic input unit 125a in order to perform an exclusive OR operation.

The optical path changing member 115 is preferably a half mirror coated prism. That is, when a thin metal such as aluminum is coated on the prism, half of the light incident on the prism is reflected and the other half is transmitted. Using the prism 115, light rays generated from the light source 112 may sequentially pass through the first logic input unit 125a and the second logic input unit 125b, and finally, one quarter of the initial light amount may be It is directed to the logic output unit 130.

The first and second field lenses 116a and 116b allow the light rays passing through the optical path changing member 115 to be irradiated to the first and second AMA elements 118a and 118b by parallel light. Preferably, the focal length f of the first field lens 116a and the focal length f of the second field lens 116b are the same.

The first logic input unit 125a is configured to provide light to the first AMA element 118a, the first light receiving element 120a for applying an electrical signal to the first AMA element 118a, and the first light receiving element 120a. It includes a first optical fiber bundle (122a) for applying. The second logic input unit 125b is configured to light the second AMA element 118b, the second light receiving element 120b for applying an electrical signal to the second AMA element 118b, and the second light receiving element 120b. And a second optical fiber bundle 122b for applying the light. Here, the mirror pixels of the first AMA element 118a and the mirror pixels of the second AMA element 118b are disposed to be tilted in opposite directions. Thus, the light rays reflected from each mirror of the first AMA element 118a are changed such that the light path is directed to the second AMA element 118b when reflected by the light path changing member 115.

The AMA elements 118a and 118b include an active matrix to which an electrical signal is applied and actuators that operate by receiving an electrical signal from the active matrix. The active matrix is a semiconductor wafer from which a simple metal oxide semiconductor (MOS) switch array, preferably a P-MOS switch array, is made and is similar to the active matrix used on a liquid crystal panel (LCD panel). The actuator may include a support layer formed on the active matrix, a lower electrode formed on the support layer and serving as a signal electrode, a strained layer formed on the lower electrode, and deformable on the lower electrode, and formed and incident on the strained layer. And an upper electrode that reflects light rays.

The light receiving elements 120a and 120b are formed in an array so as to correspond to the actuators of the AMA elements 118a and 118b, and are preferably formed as a charge coupled device (CCD). Light transmitted through the bundles 122a and 122b of the optical fiber connected to each of the light receiving elements 120a and 120b is converted into an electrical signal by the light receiving elements 120a and 120b, and then the electrical signal is converted into an AMA element 118a. 118b). When the electrical signal is applied from the MOS transistor embedded in the active matrix to the lower electrode, which is a signal electrode, and a bias voltage is applied to the upper electrode, an electric field is generated between the upper electrode and the lower electrode. By this electric field, the strained layer laminated between the upper electrode and the lower electrode causes deformation. The strained layer contracts in a direction perpendicular to the electric field, and actuators including the strained layer are bent in a direction opposite to the direction in which the support layer is formed. Thus, the upper electrode serving as a mirror at the top of each actuator is also tilted in the same direction to reflect the incident light beam.

The projection stop 126 is an optically opaque member and has an optically reflective surface and an opening formed to pass a light beam. The projection lens 128 functions to project the light beams passing through the opening of the projection stop 126 to the logic output unit 130. According to a preferred embodiment of the present invention, the optical axes of the projection stop 126 and the projection lens 128 coincide with the optical axes of the second logic input unit 125b in order to perform an exclusive OR operation.

Logic output 130 preferably includes an optical fiber bundle. The optical fiber bundle 130 may be used alone to serve as a light receiving element, or may be used as an input of another logic circuit.

Referring to the logic operation method using the optical logic device 100 according to the present invention having the above-described structure in more detail as follows.

First, the light rays emitted from the light emitting diodes 112 pass through the source stop 114 and are incident on the optical path changing member 115. Since the optical path changing member 115 is composed of a half mirror coated prism, one half of the incident light amount passes through the optical path changing member 115 to be parallel to the first light through the first field lens 116a. The input unit 125a is irradiated.

When light transmitted through the first optical fiber bundle 122a is incident on the first light receiving element 120a, the first light receiving element 120a converts the light into an electrical signal and then converts the light into an electrical signal. ) Is applied. Each mirror of the first AMA element 118a is tilted by an applied electrical signal.

The light rays reflected from the first AMA element 118a of the first logic input unit 125a are again passed through the first field lens 116 and irradiated to the optical path changing member 115. One half of the amount of light irradiated to the optical path changing member 115 is returned to the light emitting diode 112, and the other half of the amount of light is reflected to reflect the second logic input unit 125b through the second field lens 116b. Is investigated.

When light transmitted through the second optical fiber bundle 122b is incident on the second light receiving element 120b, the second light receiving element 120b converts the light into an electrical signal and then converts the light into an electrical signal. 118b). Each mirror of the second AMA element 118b is tilted by an applied electrical signal.

Light rays reflected from the second AMA element 118b of the second logic input unit 125b are directed to the projection stop 126 via the second field lens 116b and the optical path changing member 115. In this case, the optical axes of the light emitting diodes 112 and the source stop 114 deviate from the optical axes of the first logic input unit 125a and the optical axes of the projection stop 126 and the projection lens 128 are the second logic input unit. Since the light axis coincides with the optical axis of 125b, the light beam passes through the opening of the projection stop 126 only when the mirror pixel of any one of the first and second AMA elements 118a and 118b is tilted. This will be described in more detail with reference to FIG. 2 as follows.

FIG. 2 is a logic table showing an exclusive OR operation by the optical logic element of the present invention shown in FIG. 1.

Referring to FIG. 2, when the mirror of the AMA device is tilted as state 1 and when the mirror is not tilted as state 0, when the states of the first logic input unit 125a and the second logic input unit 125b are different from each other, The logic output unit 130 is in a state of 1.

That is, when the mirror of any one of the first AMA element 118a and the second AMA element 118b is tilted, the light beams sequentially reflected from the first logic input unit 125a and the second logic input unit 125b are used. Is projected by the projection lens 128 to the logic output 130 after passing through the opening of the projection stop 126.

On the other hand, if both the mirror of the first AMA element 118a and the mirror of the second AMA element 118b are not tilted or tilted, they are sequentially reflected from the first logic input unit 125a and the second logic input unit 125b. The light beam is phased out of the projection stop 126 and thus cannot reach the logic output unit 130.

In this manner, the optical logic device of the present invention performs an exclusive OR operation.

As described above, the present invention configures two logic input units using an optical modulation device including an AMA device, a light receiving device for applying an electrical signal to the AMA device, and an optical fiber bundle for applying light to the light receiving device. A half mirror coated prism is also used to direct light rays from the light source through the two logic inputs sequentially to a logic output including the fiber bundles.

Therefore, according to the present invention, it is possible to fabricate a micro optical logic gate using an AMA device. In addition, since independent logic operations may be performed for each mirror pixel of the AMA device, a large amount of data may be processed simultaneously.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed within the scope of the present invention without departing from the spirit and scope of the invention described in the claims below. I can understand that you can.

Claims (18)

A light source 112 for generating light rays; Applying an electrical signal to the first actuated mirror array (AMA) element 118a and mirrored to the first actuated mirror array element, the mirror element being modified to modulate the light beam by an applied electrical signal. A first logic input unit 125a including a first light receiving element 120a for the first; A second actuated mirror array element 118b consisting of mirror pixels deformed to modulate the light beam by an applied electrical signal and a second for applying an electrical signal to the second actuated mirror array element A second logic input unit 125b including a light receiving element 120b; Optical path changing means (115) for changing an optical path such that light rays generated from the light source are sequentially modulated by the first actuated mirror array element and the second actuated mirror array element; And And a projection lens (128) for projecting light rays passing through the first and second logic input units sequentially to the logic output unit (130). The light emitting device of claim 1, wherein the first logic input unit 125a further includes a first optical fiber bundle 122a connected to the first light receiving element 120a to apply light to the first light receiving element. The second logic input unit 125b further includes a second optical fiber bundle 122b connected to the second light receiving element 120b to apply light to the second light receiving element. . The method of claim 1, wherein the first light receiving element 120a is formed corresponding to each pixel of the first actuated mirror array element 118a, and the second light receiving element 120b is formed in the second actuating element. An optical logic element characterized in that it is formed corresponding to each pixel of the tilted mirror array element (118b). The optical logic device of claim 1, wherein the light source (112) is a light emitting diode (LED). The optical logic element according to claim 1, wherein the optical path changing means (115) is composed of a half mirror coated prism to transmit half of the incident light and reflect the other half. The optical logic device of claim 1, wherein the logic output unit (130) comprises an optical fiber bundle. The method of claim 1, wherein the mirror pixels of the first actuated mirror array element 118a and the mirror pixels of the second actuated mirror array element 118b are arranged to be tilted in opposite directions to each other. Optical logic device. The first actuated mirror array element 118a according to claim 1, wherein the light source passes through the source stop 114 and the optical path changing means 115 for concentrating the flux of the light rays generated from the light source 112. ), The first field lens 116a for irradiating with parallel light, the second field lens 116b for irradiating with parallel light to the second actuated mirror array element 118b, and the first and second And a projection stop (126) having an opening for passing light rays sequentially reflected from the logic inputs (125a, 125b). The optical axis of claim 8, wherein the optical axes of the light source 112 and the source stop 114 deviate from the optical axes of the first logic input unit 125a, and the optical axes of the projection stop 126 and the projection lens 128 are respectively. And an optical axis coinciding with the optical axis of the second logic input section (125b). The optical logic element of claim 8, wherein a focal length of the first field lens (116a) and a focal length of the second field lens (116b) are the same. An actuated mirror array (AMA) element comprising an active matrix to which an electrical signal is applied, and actuators that operate by receiving an electrical signal from the active matrix; And An array of light-receiving elements connected to the active matrix so as to correspond to respective actuators of the actuated mirror array element, and converting light transmitted from the optical fiber bundle into an electrical signal to apply the electrical signal to the active matrix; An optical modulation device, characterized in that. Irradiating light rays generated from the light source to a first logic input unit including a first actuated mirror array (AMA) element consisting of a plurality of mirror pixels and a first light receiving element through optical path changing means; Deforming mirror pixels of the first actuated mirror array element by applying an electrical signal from the first light receiving element to the first actuated mirror array element; A second logic including a second actuated mirror array element and a second light receiving element, the second actuated mirror array element comprising a plurality of mirror pixels through the optical path changing means for light rays reflected from each mirror pixel of the first actuated mirror array element; Irradiating an input unit; Deforming mirror pixels of the second actuated mirror array element by applying an electrical signal from the second light receiving element to the second actuated mirror array element; And And performing a logical operation by projecting light rays reflected from each mirror pixel of the second actuated mirror array element through a projection lens to a logic output unit. 13. The method according to claim 12, wherein the optical path changing means transmits half of the incident light and reflects the other half by using a half mirror coated prism. The method of claim 12, wherein applying the electrical signal from the first light receiving element to the first actuated mirror array element to modify the mirror pixels of the first actuated mirror array element, Applying light to the first light receiving element through a first optical fiber bundle connected to the first light receiving element; Converting the light into an electrical signal through the first light receiving element; And deforming the mirror pixels by applying the electrical signal to the first actuated mirror array element. The method of claim 12, wherein applying the electrical signal from the second light receiving element to the second actuated mirror array element to modify the mirror pixels of the second actuated mirror array element, Applying light to the second light receiving element through a second bundle of optical fibers connected to the second light receiving element; Converting the light into an electrical signal through the second light receiving element; And deforming the mirror pixels by applying the electrical signal to the second actuated mirror array element. The method of claim 12, wherein the mirror pixels of the first actuated mirror array element and the mirror pixels of the second actuated mirror array element are deformed in opposite directions to each other. 13. The method of claim 12 wherein the logical operation is an exclusive OR operation. 18. The logical operation method according to claim 17, wherein when the mirror pixel of either of the first and second actuated mirror array elements is deformed, only the light beams modulated therefrom reach the logic output. .