KR970008376B1 - Optical path regulating apparatus - Google Patents

Abstract

An apparatus (30) for controlling an optical path is provided, which includes a substrate (31) having transistors and formed with conductive line patterns (33) in matrix form, an actuator array (44) mounted on the substrate and having deformation parts (39), first and second electrodes (41, 43), actuators (46) and low-level resistors (47), mirrors (45) mounted on protruded portions of the actuators and adhesive parts (35) for fixing the substrate and the actuator array and electrically contacting the conductive line patterns with the first electrodes, wherein the resistance between the inner electrodes and the adhesive parts may be reduced and maintained uniformly and the displacement amount of the deformation parts may be maintained uniformly so that the operational characteristics may be improved.

Description

Light Path Control

1 is a plan view of a conventional optical path control device.

2 is a cross-sectional view taken along the line AA of FIG. 1.

3 is a plan view of the optical path control apparatus according to the present invention.

4 is a cross-sectional view taken along the line B-B in FIG.

* Explanation of symbols for main parts of the drawings

30: optical path control device 31: driving substrate

33: actuator 35: contact terminal

37 support 39 plug

41: elastic portion 43, 47: signal and bias electrode

45: deformation 49: mirror surface

51: heatsink

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical path adjusting device for a projection display device, and more particularly, to an optical path adjusting device capable of cooling a driving substrate heated by a tube incident between mirror surfaces.

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 direct view type image display device includes a CRT (Cathode Ray Tube), but the CRT image display device has a good image quality, but there is a problem in that a large screen has an increase in weight and thickness, and a price is expensive. . Projection type image display apparatuses include a large crystal display (Liquid Crystal Display; LCD), and the like. Such a large-screen LCD can be thinned and can be reduced in weight. However, such LCDs have a high loss of light due to the flat plate, and thin film transistors for driving the LCD are formed for each pixel, so that there is a limit in increasing the aperture ratio (light transmission area).

In order to make up for the drawbacks of LCDs, a projection type image display apparatus using actuator mirror arrays (hereinafter referred to as AMAs) was developed by Aura, USA.

A projection image display device 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 tilted by the deformation of actuators, respectively. 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 at an electric field to tilt the mirror on the top.

FIG. 1 is a plan view of a conventional optical path control apparatus 10, and FIG. 2 is a cross-sectional view taken along line A-A of FIG.

The optical path control apparatus 10 includes a driving substrate 11, actuators 13 and a mirror surface 29.

The driving substrate 11 is made of an insulating material such as glass or alumina (Al ₂ O ₃ ) or a semiconductor such as silicon, and M × N (M and N are natural numbers) transistors (not shown) are formed in a matrix. It is built in the form of a matrix. In addition, contact terminals 15 electrically connected to the transistors are formed on the surface of the driving substrate 11.

The actuators 13 are composed of a support part 17, an elastic part 21, a plug 19, a deformable part 25, and signal and bias electrodes 23 and 27, in which N pieces are arranged in the longitudinal direction. M arrays are formed in which predetermined portions are connected.

The support part 17 is elongated in the vertical direction to cover the contact terminal 15 on a predetermined portion of the upper portion of the driving substrate 11, the elastic portion 21 is only a predetermined portion of the lower surface on the upper portion of the support portion 17 The remaining part is shaped to be exposed to the space, the exposed part being separated up to the adjacent actuators 13. In the above, the signal electrodes 23 are electrically separated from the actuators 13 adjacent to each other on the same array, and the bias electrodes 27 are electrically connected and grounded jointly. The plug 19 penetrates the support part 17 and the elastic part 21 to electrically connect the contact terminals 15 and the signal electrode 23.

The mirror surface 29 is formed by coating the surface of the bias electrode 27 with a metal having good reflection characteristics.

The optical path adjusting device 10 described above is perpendicular to the deformable portions 25 by an image signal applied to the signal electrodes 23 from the outside through the driving substrate 11 and a potential difference between the bias electrodes 27 in the ground state. An electric field is generated in one direction. Therefore, the deformable portions 25 are contracted in the horizontal direction, whereby stress is generated at the interface between the deformable portion 25 and the elastic portion 21. Therefore, the end of the deformable portion 25 is bent in the opposite direction to the elastic portion 21, whereby the mirror surfaces 29 are also bent to change and reflect the light path of the incident light beam.

However, the above-described conventional optical path adjusting device does not reflect the light beams incident between the mirror surfaces of the incident light beams, but is irradiated onto the driving substrate to heat the irradiated portion, and self-heats due to the dielectric loss of the deformable parts. There was a problem that the piezoelectric properties of the characteristics and deformation parts are lowered. In addition, since the bias line of the actuator array is connected and grounded in common, if the bias electrode of any one of the actuators is damaged and the electrical connection is broken, there is a problem that the array (COLUMN) direction may not operate in the array.

Accordingly, an object of the present invention is to reflect an optical flux irradiated onto a substrate without being reflected by mirror surfaces and to dissipate heat generated from the deformable portions, thereby preventing deterioration of characteristics of the transistors and deformed portions. In providing.

Another object of the present invention is to provide an optical path control apparatus capable of preventing all of the column arrays from operating even when the bias electrode of any actuator is damaged and the electrical connection is broken.

An optical path control apparatus according to the present invention for achieving the above objects includes a drive substrate having transistors embedded in a matrix and having contact terminals electrically connected to the transistors on a surface thereof; Surrounding the contact terminals on the driving substrate, the neighboring ones and the support parts separated from each other and the lower portion is in contact with the upper portion of the support portion so that the lower portion is in contact with the rest portion including the other end is exposed elastic space And deformable parts formed of a thin ceramic on the elastic parts and having first and second electrodes formed on both surfaces thereof, and electrically connecting the contact terminals and the first electrodes through the support parts and the elastic parts. Actuators formed of a plug and separated from neighboring ones, a mirror surface formed on the surface of the actuator, a predetermined portion of the upper portion of the drive substrate and the one surface of the actuators are formed.

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

3 is a plan view of the optical path control device 30 according to an embodiment of the present invention, Figure 4 is a cross-sectional view taken along the line B-B.

The optical path control device 30 includes a driving substrate 31, actuators 33, mirror surfaces 49, and a heat sink 51.

The driving substrate 31 is made of an insulating material such as glass or alumina (Al ₂ O ₃ ), or a semiconductor such as silicon, and M × N transistors (not shown) are embedded in a matrix form. In addition, connection terminals 35 electrically connected to the transistors are formed on the surface of the driving substrate 31.

Actuators 33 are formed on the driving substrate 31 to correspond to the transistors M × N pieces, each of the actuators 33 are the support portion 37, the elastic portion 41, the plug (plug: 39) ), The deformable portion 45 and the signal and bias electrodes 43 and 47 are completely separated from the neighboring actuators 34.

The support part 37 is formed to cover the contact terminal 35 on the driving substrate 31, and is separated from the support parts 37 of the adjacent actuators 33. The elastic portion 41 is formed such that only a predetermined portion of the lower surface is in contact with one end edge of the upper portion of the support portion 37 and the remaining portion including the other end is exposed to the space. The support portion 37 and the elastic portion 41 are formed by a method such as sputtering or chemical vapor deposition (hereinafter referred to as CVD) of an insulating ceramic such as silicon nitride or silicon oxide. The deformable portion 45 is formed on the surface of the elastic portion 41 via the signal electrode 43 formed on the lower surface, and the bias electrode 47 is formed on the upper surface of the deformable portion 45. The deformation part 45 may be a piezoelectric ceramic such as BaTiO ₃ , PZT (Pb (Zr, Ti) O ₃ ) or PLZT (Pb, La) (Zr, Ti) O ₃ ), or PMN (Pb (Mg, Nb). It is formed by applying a total distortion ceramic such as) O ₃ ) to a thickness of about 0.2 to 2 μm. The signal electrode 43 is formed by applying a bias electrode 47 platinum (Pt) or platinum / titanium (Pt / Ti) or the like to a thickness of about 500 to 2000 kPa by sputtering or vacuum deposition. The signal electrode 43 is formed so as not to be exposed to one edge of the elastic part 41 and the support part 37.

The plug 39 penetrates the support part 37 and the elastic part 41 to electrically connect the contact terminal 35 and the signal electrode 43 to be formed of tungsten (W) or titanium.

The mirror surface 49 is formed by applying a metal having good reflection characteristics such as aluminum or silver to the surface of the bias electrode 47 to a thickness of about 500 to 2000 kPa by sputtering or vacuum deposition. In the above, the mirror surface 49 may be formed on the surface of the deformable portion 45. In this case, the bias electrode 47 is not formed separately, and the mirror surface 49 simultaneously performs the function of the bias electrode.

The heat sink 51 is formed on the exposed surface of the driving substrate 31 and on one surface of the actuators 33. The heat sink 51 is formed of gold (Au), silver (Ag), copper (Cu), or aluminum (Al), which has good thermal and electrical conductivity and reflection characteristics. The heat sink 51 has a small mirror surface on the surface of the driving substrate 31. It should be equal to the spacing between the 49 and the one side surface of the actuators 33 should be electrically connected to the bias electrodes 47. Therefore, the heat sink 51 is not reflected by the mirror surfaces 49, but reflects the light beam irradiated to the driving substrate 31 therebetween to reduce the generation of heat. In addition, the heat sink 51 is formed on one side of the actuators 33 to dissipate the self-heating caused by the dielectric loss generated in the deformable parts 45 during driving, thereby deteriorating the piezoelectric characteristics of the deformable parts 45. It is also used as a common electrode for electrically connecting the bias electrodes 47 which are electrically separated, so that the remaining actuators 33 can be normally driven even if any of the actuators 33 are damaged.

As described above, the optical path control apparatus according to the present invention comprises: a driving substrate having transistors embedded in a matrix and having contact terminals electrically connected to the transistors on a surface thereof; Adjacent ones surrounding the contact terminals on the driving substrate are separated from each other, and elastic parts having a predetermined lower portion contacted with one side of the upper portion of the support portions and the remaining portion including the other end are exposed to the space. And a plug formed of a thin ceramic on the elastic parts and having first and second electrodes formed on both surfaces thereof, and electrically connecting the contact terminals and the first electrodes through the support parts and the elastic parts. Actuators are separated from the neighboring ones, and formed on the mirror surface formed on the actuator surface, a predetermined portion of the upper portion of the drive substrate and one side surface of the actuators.

Accordingly, the present invention prevents the generation of heat by reflecting the light beam irradiated on the surface of the driver between the mirror surface and to prevent the generation of heat and to dissipate the self-heating generated in the deformation parts by the dielectric loss to improve the characteristics of the transistors and deformation parts To prevent degradation. In addition, since the heat sink is electrically connected to the bias electrodes of the actuators that have been separated, there is an advantage in that the remaining actuators are normally driven even if any actuator is damaged.

As described above, the present invention has been described and illustrated with reference to a preferred embodiment. Those skilled in the art can make various modifications without departing from the spirit and scope of the invention.

Claims (6)

A driving substrate having transistors embedded in a matrix and having contact terminals electrically connected to the transistors on a surface thereof; Surrounding the contact terminals on the driving substrate, the neighboring ones and the support parts separated from each other and the lower portion is in contact with the upper portion of the support portion so that the lower portion is in contact with the remaining portion including the other end is exposed to the space And a deformation part formed of a thin ceramic on top of the elastic parts and having first and second electrodes formed on both surfaces thereof, and electrically connecting the contact terminals and the first electrodes through the support parts and the elastic parts. And an actuator separated from neighboring ones, a mirror surface formed on the surface of the actuator, a predetermined portion of the upper portion of the driving substrate, and a heat sink formed on one surface of the actuators. The optical path control device according to claim 1, wherein the deformable portion is made of a whole warp or piezoelectric ceramic. The optical path adjusting apparatus of claim 1, wherein the heat sink is formed wider than a distance between mirrors on the driving substrate. 4. The optical path control apparatus as claimed in claim 3, wherein the heat sink is electrically connected to a second electrode at one surface of the actuators. The optical path control device according to claim 4, wherein the heat sink is formed of a metal having thermal, electrical conductivity, and reflective properties. The optical path control device according to claim 5, wherein the heat sink is formed of gold, silver copper or aluminum.