KR970003002B1 - Optical path regulating apparatus - Google Patents

Abstract

a substrate which has transistors of matrix type, and has conduction wire patterns on its surface, and contact terminals formed on some part of the conduction wire patterns; an actuator array where M x N actuators comprising a transformation part, a first electrode and a second electrode, are arranged; reflective mirrors built in the top of the projection part of the actuators; and an anisotropic conductive glue tape which glues the substrate and the actuators and contacts between the contact terminals(35) and the first electrodes electrically.

Description

Light Path Control

1 is a cross-sectional view of a conventional optical path control device.

2 is a cross-sectional view of the optical path control apparatus according to the present invention.

* Explanation of symbols for main parts of the drawings

30: optical path control device 31: substrate

33: wire pattern 35: contact terminal

37: anisotropic conductive adhesive tape 38: conductive particles

39: insulating adhesive tape 40: actuator array

41: deformation portion 43: internal electrode

44: groove 45: external electrode

46: Actuator 47: Reflector

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical path adjusting device used in a projection image display device, and more particularly, to an optical path adjusting device capable of facilitating electrical connection between a conductor pattern in a substrate and a signal electrode of an actuator so that actuators are driven independently.

An image display apparatus is classified into a direct view type image display apparatus and a projection type image display apparatus according to a display method. The timely image display device includes a CRT (Cathode Ray Tube). The CRT image display device has good image quality, but there are limitations in implementing a large screen due to problems such as an increase in weight and thickness and an expensive price as the screen is enlarged. . Projection type image display apparatuses include a large crystal display (hereinafter referred to as an LCD). Such a large display LCD can be thinned to reduce weight. However, such LCDs have a high loss of light due to the polarizing plate, and thin film transistors for driving the LCD are formed for each pixel, so that there is a limit to increase the aperture ratio (light transmission area), and thus the efficiency of light is very low.

In order to make up for the shortcomings of LCDs, a projection type image display apparatus using an Actuated Mirror Array (hereinafter referred to as AMA) has been developed by Aura, USA. A projection image display apparatus using AMA separates white light emitted from a light source into red, green, and blue light beams, and then reflects these light beams to reflectors that are inclined by the deformation of actuators. paths, and adjusts the amount of light beams to project on the screen to display an image. The AMA is classified into a one-dimensional AMA having an actuator of M × 1 and a two-dimensional AMA having an M × N according to the driving method. The actuator includes a deformable part and electrodes formed of a piezoelectric material or a warping material, and deforms when an electric field is generated to tilt the mirror on the top.

1 is a cross-sectional view of a conventional optical path control device 10.

The optical path control apparatus 10 includes a substrate 11, an actuator array 20, and a reflector 27.

The substrate 11 is made of an insulating material or a semiconductor such as silicon, and on the surface of the substrate, active transistors (not shown) and lead patterns 13 are formed. A portion of the conductive pattern 13 is exposed on the surface of the substrate 11, and contact terminals 15 made of metal are formed on the exposed conductive pattern 13.

The actuator array 20 includes deformation portions 21 formed of piezo electric ceramic polarized in either direction of the x-axis. The deformable parts 21 include internal electrodes 23 used as signal electrodes between adjacent deformable parts, and external electrodes 25 used as common ground electrodes on the inner surface of the grooves 24 formed thereon. have. The half portions of the two side deformation parts 21 around the inner electrodes 23 form the iron actuator unit actuators 26 including the external electrodes 25. Protrusions are formed around the internal electrodes 23 at the lower portions of the actuators 26, and low resistance contacts 19 contacting the internal electrodes 23 by applying a conductive adhesive to the lower surfaces of the protruding portions are formed. The actuator array 20 described above is mounted on the substrate 11 such that the low resistance contacts 19 are in contact with the contact terminals 15.

The reflectors 27 are mounted on the surface of the actuators 26 of the actuator array 20.

The optical path control device 10 described above, when an image signal is applied to the internal electrodes 25 of the actuators 26 from the conductive wire patterns 13 through the contact terminals 15, the electric field is applied to the deformation parts 21. Is generated to deform the actuators 26. Therefore, the reflector mounted on the surface of the actuator 26 is inclined to change the light path of the reflected light with respect to the incident light. When the image signal is applied to the internal electrodes 23, the deformation parts 21 may be formed at the protrusions on the deformation parts 21 by the voltage difference between the internal electrodes 23 and the external electrodes 25. Electric field is generated. Therefore, in the upper protrusions of the deformable parts 21, electric fields in opposite directions with the neighboring protrusions are generated with the internal electrodes 23 interposed therebetween. Therefore, the deformable parts 21 forming the protrusions in the actuators 26 are contracted in the -y direction by matching the electric field direction and the polarization direction on one side and extending in the y direction opposite to the other side, so that the reflector 27 is It will tilt. The inclination of the reflectors 27 is proportional to the magnitude of the image signal applied to the internal electrodes 23. In the above, the low resistance contact portions 19 improve the operating characteristics by improving the electrical connection between the contact terminals 15 and the internal electrodes 23. The conductive adhesive is contacted by a method such as a silk screen. It is formed by applying on top of the terminal or by dipping the lower protrusions of the actuators into a conductive adhesive.

However, when the actuator array is mounted on the substrate, the conductive contacts for forming the low resistance contact are spread, so the actuator distances of the actuators due to the increase in the number of pixels become narrow, so that the actuators are electrically shorted and difficult to operate independently. there was.

Accordingly, an object of the present invention is to provide an optical path control apparatus that can prevent the actuators from being electrically shorted and malfunctioning.

According to an aspect of the present invention, there is provided an optical path control apparatus, comprising: a substrate having transistors in a matrix form and having conductive patterns on a surface thereof, and contact terminals formed on predetermined portions of the conductive patterns; Mounted on the substrate, and having a deformed portion, the first electrode between the deformable portion and the second electrode applied to the inner surface of the grooves formed on the deformable portion, the center of the deformable portion An actuator array having M × N arrangements of iron-shaped actuators composed of halves and second electrodes; Reflectors mounted on top of protrusions of the actuators; An anisotropically conductive adhesive tape interposed between the substrate and the actuator array to bond the substrate and the actuator and to provide anisotropic electrical contact between the contact terminals and the first electrodes.

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

2 is a cross-sectional view of the optical path control device 30 according to an embodiment of the present invention.

The optical path control device 30 includes a substrate 31, an anisotropic conductive adhesive tape 37, an actuator array 40, and a reflector 47.

The substrate 31 is made of an insulating material such as glass or Al ₂ O ₃ including active matrix transistors (not shown) and the conductive wire pattern 33. In addition, the substrate 31 may be formed of a silicon wafer. A portion of the conductive pattern 33 is exposed on the surface of the substrate 31, and contact terminals 35 made of a metal such as aluminum (Al) are formed on the exposed conductive pattern 33. have. The conductive line patterns 33 transmit an image signal applied from an external circuit (not shown) to corresponding pixels, and the contact terminals 35 each of the pixels corresponding to the conductive line patterns 33. Connect electrically well.

The actuator array 40 includes the deformable portions 41 and the internal and external electrodes 43 and 45, and includes M × N unit actuators 46 corresponding to one pixel. The deformation parts 41 are made of piezoceramic such as BaTiO ₃ , PZT (Pb (Zr, Ti) O ₃ ) or PLZT ((Pb, La) (Zr, Zi) O ₃ ), and are polarized in one direction of the x-axis. It is. In addition, the deformable portions 41 may be formed of an electrodistorted ceramic such as a solid solution time PMN-PT or the like in the PMN (Pb (Mg, Nb) O ₃ ) system. In addition, the internal electrodes 43 are formed between the predetermined deformation parts 41 and neighboring deformation parts to be used as signal electrodes, and the external electrodes 45 are formed in the grooves 44 formed on the deformation parts 41. It is applied to the inner surface and used as a common ground electrode. The half portions of the two side deformation parts 41 around the inner electrodes 43 become the iron actuator 46 including the external electrodes 45. The actuators 46 generate electric fields in opposite directions along the x-axis by the voltage difference between the internal electrodes 43 and the external electrodes 45. The deformation parts 41 on both sides of the unit actuators 46 generate electric fields in opposite directions with respect to the internal electrodes 43. therefore. When the image signals are applied to the internal electrodes 43, the actuators 46 made of piezoelectric ceramics are contracted along the y-axis, and the upper portions of the other deformation portions which do not coincide with each other are contracted along the y-axis. Stretch along the y axis. Thus, the actuators 46 are inclined toward one side deformations where the upper surface contracts along the y axis. The degree of inclination of the upper surface of the actuators 46 is proportional to the image signal level.

The anisotropically conductive adhesive tape 37 is made of an insulating adhesive tape 39 such as epoxy containing conductive particles 38 such as metal, and is interposed between the substrate 31 and the actuator array 40. The anisotropic conductive adhesive tape 37 has conductive particles 37 randomly distributed on a thin insulating adhesive tape 39, and the conductive particles 37 are insulated from each other by the insulating adhesive tape 39. The anisotropic conductive adhesive tape 37 is thermally compressed between the substrate 31 and the actuator array 40. The insulating adhesive tape 39 is melted by heat to bond the substrate 31 and the actuator array 40 to each other. Some of the conductive particles 37 are electrically connected to the contact terminals 35 and the internal electrodes 43 by contacting each other. Each of the actuators 46 is insulated by the insulating adhesive tape 39. That is, the anisotropically conductive adhesive tape 37 conducts on the y axis to electrically connect the contact terminals 35 and the internal electrodes 43 and insulate on the x axis to insulate the actuators 46, respectively.

The reflectors 47 are mounted on the surface of the protrusions of the actuators 46. The reflector 47 is inclined according to the deformation of the actuators 46 to change the optical path of the light reflected with respect to the incident light.

As described above, the anisotropically conductive adhesive tape made of an insulating adhesive tape in which conductive particles are arbitrarily distributed is thermocompressed to bond the substrate and the actuator array by the insulating adhesive tape, and the contact terminals and the internal electrodes are electrically connected by the conductive particles. Connect.

Therefore, the present invention can prevent the malfunction by driving the actuators independently even when the contact terminals 35 are very narrow by insulating the substrate and the actuator array by the insulating adhesive tape and insulating the conductive particles to be connected at the same time. There is an advantage.

Claims (4)

A substrate having transistors in matrix form and having conductive patterns formed on the surface thereof and contact terminals formed on predetermined portions of the conductive patterns; Mounted on the substrate. Deformed parts, first electrodes between the deformable parts and second electrodes coated on the inner surface of the grooves formed on the deformed parts, and having half of the deformed parts and the second electrodes centered on the first electrodes. An actuator array in which M × N pieces are formed of iron and shaped actuators; Reflectors mounted on top of protrusions of the actuators; An optical path having an anisotropically conductive adhesive tape disposed between the substrate and the actuator array to bond the substrate and the actuator and to provide anisotropic electrical contact between the contact terminals 35 and the first electrodes. Regulator. The optical path control device according to claim 1, wherein the deformation portion is formed of a piezoelectric ceramic such as BaTiO ₃ , PZT, or PLZT. The optical path control device according to claim 1, wherein the deformable portion is formed of an electrostrict ceramic such as PMT-PT. The optical path control device according to claim 1, wherein the anisotropic conductive adhesive tape has conductive particles, such as metal, arbitrarily distributed on an insulating adhesive tape such as epoxy.