KR100209941B1 - Thin-film optical path control device with large driving angle - Google Patents

Abstract

A thin film type optical path adjusting device capable of increasing the driving angle of a mirror is disclosed. The device includes an active matrix having a pad, a plug, a protective layer and an etch stop layer thereon, and an actuator formed on the active matrix. The actuator is composed of at least two actuators having a lower electrode, a deformable portion, an upper electrode and a membrane and driving in opposite directions to each other. Therefore, the mirror can be driven at a driving angle of 2 to 3 times or more even in a small area, thereby improving the light efficiency of the light incident from the light source, and improving the contrast.

Description

Thin-film optical path control device with large driving angle

The present invention relates to AMA (Actuated Mirror Arrays), a thin film type optical path control device, and more particularly, to an AMA device capable of increasing a driving angle of a built-in mirror while having a small area.

An optical path adjusting device or an optical modulator capable of adjusting the light flux may be variously applied to optical communication, image processing, and information display apparatus. In general, such devices are classified into two types according to their optical properties. One type is a direct view type image display device, such as a CRT (Cathode Ray Tube), and the other type is a projection type image such as a liquid crystal display (LCD), an AMA, and a deformable mirror device (DMD). It is a display device. Although the CRT apparatus has excellent image quality, as the screen is enlarged, the weight and volume of the apparatus increase, thereby increasing the manufacturing cost. In contrast, a liquid crystal display (LCD) has a simple optical structure and can be formed thin so that the weight can be reduced and the volume can be reduced. However, the liquid crystal display device is inferior in efficiency to have a light efficiency of 1 to 2% due to polarized light, has a disadvantage in that the response speed is slow and the liquid crystal material therein tends to overheat. Therefore, in order to solve the above problem, a thin film type image display apparatus such as AMA or DMD has been developed. Currently, AMA devices can achieve 10% or more light efficiency, while DMD devices have about 5% light efficiency.

The AMA device is a device that can adjust the luminous flux so that each mirror installed therein reflects the light flowing from the light source at a predetermined angle, and the reflected light passes through a slit to form an image on the screen. to be. Therefore, the structure and operation principle thereof are simple, and high light efficiency can be obtained compared to a liquid crystal display device, a DMD device, or the like. In addition, the AMA device can improve contrast to produce a brighter and clearer image, and is not affected by the polarity of the incident light flux and also does not affect the polarity of the reflected light flux. The mirrors embedded in the AMA device are inclined by the electric field generated by corresponding to the slits. Therefore, the luminous flux incident from the light source is adjusted at a predetermined angle to form an image on the screen. In general, each actuator causes deformation in accordance with the electric field generated by the applied electric image signal and the bias voltage. When the actuator causes deformation, each of the mirrors mounted on top of the actuator is inclined. Accordingly, the inclined mirrors can reflect light incident from the light source at a predetermined angle. 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. In addition, an electrostrictive material such as PMN (Pb (Mg, Nb) O ₃ ) may be used as a constituent material of the actuator.

Such AMA devices are largely classified into bulk type devices and thin film type devices. The bulk optical path control device is disclosed in, for example, US Pat. No. 5,085,497 (issued to Gregory Um, et al.) 5,159,225 (issued to Gregory Um), 5,175,465 (issued to Gregory Um, et al. have. The bulk optical path adjusting device is to cut a thin layer of multilayer ceramic, mount a ceramic wafer having a metal electrode formed therein in an active matrix in which a transistor is built, and then process it by sawing. This is done by installing a mirror. However, since the bulk light path control device must separate the actuators by a sawing method, very high precision is required in design and manufacturing, and the response speed of the deformation part is slow. Therefore, a thin film type optical path control apparatus that can be manufactured using a semiconductor manufacturing process has been developed.

The thin film type optical path control device is disclosed in Korean Patent Application No. 95-13358 (name of the invention: optical path control device) filed by the applicant to the Korean Intellectual Property Office.

FIG. 1 shows a plan view of the thin film type optical path adjusting device described in the above prior application, and FIG. 2 shows a cross-sectional view taken along the line AA ′ of the device shown in FIG. 1. As shown in Fig. 1 and Fig. 2, the thin film type optical path adjusting device is composed of an active matrix 1 and an actuator 3 formed on the active matrix 1.

The active matrix 1 is formed of a semiconductor such as silicon (Si), and includes M × N (M, N is an integer) MOS transistors (not shown). In addition, the active matrix 1 can be formed using an insulating material such as glass or alumina (Al ₂ O ₃ ).

The pad 5 is formed on one side of the active matrix 1. The pad 5 is electrically connected to the MOS transistor embedded in the active matrix 1.

The actuator 3 is composed of a membrane 7, a plug 9, a lower electrode 11, a deformable portion 15, and an upper electrode 17. The membrane 7 is laminated to have a thickness of about 0.01 to 1.0 탆 using an insulating material such as nitride. As shown in FIG. 1, the membrane 7 has a rectangular concave portion formed on one side thereof with a central portion thereof, and a quadrangular protrusion portion corresponding to the concave portion formed on the other side thereof. The concave portion of the membrane 7 is fitted with a rectangular protrusion of the membrane of the adjacent actuator, and the protrusion of the membrane 7 is fitted with the concave portion of the adjacent membrane. 2, the membrane 7 is formed such that one side is in contact with the top of the active matrix 1 and the other side is parallel to the active matrix 1 via an air gap 8. do.

The plug 9 is formed perpendicular to the portion of the membrane 7 in which the pad 5 is formed. The plug 9 is formed by filling a metal such as tungsten (W) or titanium (Ti) and is electrically connected to the pad 5.

The lower electrode 11 is stacked on the membrane 7 so as to have a thickness of about 500 to about 2000 kPa using platinum (Pt) or titanium. On one side of the lower electrode 11, a stripe 13 for improving light efficiency is formed by a sawing method so that the membrane 7 is exposed. The stripe 13 uniformly operates the lower electrode 11 and the upper electrode 17 to prevent the incident light beam from being diffusely reflected.

The deformable portion 15 is laminated on the lower electrode 11 to have a thickness of about 0.01 to 1.0 탆 using piezoelectric materials such as PZT or PLZT, or electrodistortion materials such as PMN. The deformable portion 15 is formed to fill the stripe 13 formed on one side of the lower electrode 11.

The upper electrode 17 is stacked on the deformable portion 15 to have a thickness of about 500 to 1000 mW using a metal having good electrical conductivity and reflective properties such as aluminum (Al) or silver (Ag). A bias voltage is applied to the upper electrode 17, and at the same time, the upper electrode 17 also functions as a reflective layer reflecting the incident light beam.

In the above-described thin film type optical path adjusting device, the image signal generated from the MOS transistor embedded in the active matrix 1 is applied to the lower electrode 11 through the pad 5 and the plug 9. At the same time, a bias voltage is applied to the upper electrode 17 to generate an electric field between the upper electrode 17 and the lower electrode 11. Therefore, the deformable portion 15 contracts in a direction perpendicular to the electric field, and the actuator 3 including the deformable portion 15 is bent in a direction opposite to the direction in which the membrane 7 is formed, and thus the upper portion of the actuator 3 The upper electrode 17 is also inclined in the same direction. The light beam incident from the light source is reflected by the upper electrode 17, and the reflected light beam is projected onto the screen through the slit to form an image.

However, in the above-described thin film type optical path adjusting device described above, the driving angle is reduced and the light efficiency is lowered by reflecting the light beam by driving only a part of the upper electrode. In addition, since the displacement of the actuator including the deformable portion is small, there is a disadvantage that the contrast of the image is reduced because the driving angle of the mirror is small. In addition, there is a problem in the design of the system, such as the gap between the light source and the screen is narrowed because the driving angle of the mirror is small.

Accordingly, an object of the present invention is to provide a thin film type optical path control apparatus that can form an actuator including at least two actuators driving in opposite directions to increase a driving angle of a mirror while having a narrow area.

1 is a plan view of a thin film type optical path adjusting device described in the applicant's prior application.

FIG. 2 is a cross-sectional view taken along line a′a ′ of the apparatus shown in FIG. 1.

3 is a plan view of a thin film type optical path control device according to a first embodiment of the present invention.

FIG. 4 is a cross-sectional view of the apparatus shown in FIG. 3 taken along line b′b ′.

FIG. 5 is a cross-sectional view of the apparatus shown in FIG. 3 taken along line c-c '.

6A to 6C are manufacturing process diagrams of the apparatus shown in FIG. 4.

7A to 7B are manufacturing process diagrams of the apparatus shown in FIG. 5.

8 is a plan view of a thin film type optical path control apparatus according to a second embodiment of the present invention.

FIG. 9 is a cross-sectional view of the apparatus shown in FIG. 8 taken along line e′e ′.

FIG. 10 is a cross-sectional view taken along the line f ′ f ′ of the apparatus shown in FIG. 8.

<Explanation of symbols on the main parts of the drawings>

21: active matrix 23: protective layer

25: etching prevention layer 27: victim layer

29: first lower membrane 31: lower electrode

33: deformation part 37, 38: 1st actuating part

39: first upper membrane 41: second actuating portion

43: Mirror 45, 46: Third actuating part

47: second upper membrane 49, 50: fourth actuating part

51: 5th actuating part 53: 2nd lower membrane

55: third lower membrane

In order to achieve the above object, the present invention,

An active matrix having M × N (M, N is an integer) transistors and pads formed on one side thereof; And

Iii) a lower electrode stacked on one side in contact with an upper portion of the active matrix and the other side parallel to the active matrix via a first air gap, ii) a deformed portion stacked on top of the lower electrode, and iii) the deformed portion. Provided is a thin film type optical path control device including an actuator having a plurality of upper electrodes stacked on top of each other and having at least two actuators driving in opposite directions.

The active matrix may include: i) a protective layer stacked on top of the active matrix and the pad, ii) an etch stop layer stacked on top of the protective layer, and iii) the etch stop layer and the protective layer from the etch stop layer. It further comprises a plug vertically formed to the pad.

According to the first embodiment of the present invention, the actuator includes two first actuators having a first lower membrane stacked in parallel with the etch stop layer via a first air gap at a lower end of the lower electrode, A second actuator having a first upper membrane stacked on the upper electrode and a central portion in contact with an upper portion of the upper electrode and having a mirror formed on the other side in parallel with the first upper membrane via a second air gap; Includes more wealth.

Preferably, the mirror is formed of a flat plate having a groove having a 'U' shape at the center and is composed of silver (Ag) or aluminum (Al).

For example, the first actuating portions are formed on both sides of the active matrix with the first lower membrane, and the second actuating portion has the first upper membrane and the mirror to form the active matrix. It is formed integrally with the first actuating parts in the upper center, the first actuating parts and the second actuating part together have a 'W' shape on the same plane.

Preferably, the first actuating parts and the second actuating part are driven in opposite directions.

In addition, according to the second embodiment of the present invention, the actuator may include two third actuators each having a second lower membrane stacked in parallel with the etch stop layer through a first air gap at a lower end of the lower electrode. Two fourth actuators each having a second upper membrane stacked on the upper electrode, and a third lower stacked parallel to the etch stop layer via a first air gap at a lower end of the lower electrode; The apparatus further includes a fifth actuator having a central portion in contact with one side of the membrane and the upper electrode and having a mirror formed at one side thereof in parallel with the upper electrode.

Preferably, the third actuators are formed on both sides of the active matrix, and the fifth actuators are integrally formed with the third actuators on the center of the active matrix. The fourth actuating parts are integrally formed with the third actuating parts and the fifth actuating part between the third actuating parts and the fifth actuating part, and the third actuating parts. The fourth actuator and the fifth actuator have a shape in which 'U', 'T', and 'U' are sequentially coupled on the same plane.

Preferably, the third actuating parts, the fifth actuating part and the fourth actuating part are driven in opposite directions to each other.

In the above-described thin film type optical path adjusting device according to the first embodiment of the present invention, an image signal is applied to the lower electrode, and a bias voltage is applied to the upper electrode. Therefore, an electric field is generated between the upper electrode and the lower electrode. By this electric field, the deformation portion between the upper electrode and the lower electrode causes deformation. The deformable portion contracts in a direction perpendicular to the electric field, thereby causing the first actuating portions to deform with a driving angle having a magnitude of θ. The first actuating parts are bent in a direction opposite to the direction in which the first lower membrane is formed. In addition, when an image signal is applied to the lower electrode and a bias voltage is applied to the upper electrode, the deformed portion of the second actuating portion also causes contraction in a direction perpendicular to the electric field. Accordingly, the second actuating part also causes deformation with a driving angle of θ size. The second actuating portion is bent in a direction opposite to the direction in which the first upper membrane is formed. The driving angles of the first actuating parts and the second actuating parts are the same in magnitude and the driving directions are opposite to each other. Therefore, the sum of the driving angles of the first actuating parts and the second actuating parts is 2θ. Since the mirror reflecting the light beam incident from the light source is formed on the second actuating part, the mirror is driven with a driving angle of 2θ.

In addition, in the above-described thin film type optical path control apparatus according to the second embodiment of the present invention, a process in which an electric field is generated to cause deformation of the deformation part is the same as in the first embodiment. Therefore, the deformable parts of the third actuating parts contract in a direction perpendicular to the electric field, and thus the third actuating parts are bent at a driving angle having a magnitude of θ. The third actuating parts are bent in a direction opposite to the direction in which the second lower membrane is formed. At the same time, the deformed portions of the fourth actuating portions also cause contraction in a direction perpendicular to the electric field. Accordingly, the fourth actuators also cause deformation with a driving angle of θ. The fourth actuating parts are bent in a direction opposite to the direction in which the second upper membrane is formed. In addition, the deformation portion of the fifth actuating portion also causes deformation. Therefore, the fifth actuating part also causes deformation with a driving angle of θ. The fifth actuating part is bent in a direction opposite to the direction in which the third lower membrane is formed. The magnitude and the driving direction of the driving angles of the third and fifth actuators are the same. In contrast, the fourth actuating parts have the same driving angle but the driving direction is opposite to the driving directions of the third actuating parts and the fifth actuating parts. Therefore, the sum of the driving angles of the third actuating parts, the fourth actuating part, and the fifth actuating part is 3θ. Since the mirror reflecting the light beam incident from the light source is formed on the fifth actuator, the mirror is driven with a driving angle of 3θ.

Therefore, the above-described thin film type optical path adjusting device according to the present invention can drive the mirror at a driving angle of 2 to 3 times or more as compared to the optical path adjusting device described in the preceding application while having a narrow area. As a result, the light efficiency of the light beam incident from the light source can be increased, and the contrast can be improved to form a bright and clear image. Also, in the design of the system, it is possible to facilitate the design of the system by widening the distance between the light source and the screen.

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

Example 1

3 is a plan view showing a thin film type optical path adjusting device according to a first embodiment of the present invention, FIG. 4 is a cross-sectional view taken along line bb ′ of the device shown in FIG. 3, and FIG. 5 is shown in FIG. 3. A cross-sectional view of a device cut in cc 'lines is shown. 6A to 6C are manufacturing process diagrams of the apparatus shown in FIG. 4, and FIGS. 7A to 7B are manufacturing process diagrams of the apparatus shown in FIG. 5. 4 and 5, the same reference numerals are used for the same members as in FIG.

Referring to FIG. 3, the thin film type optical path adjusting device according to the present embodiment includes the active matrix 21 and the two first actuating parts 37 and 38 formed on both sides of the active matrix 21 and the active matrix. And a second actuating portion 41 formed at the center upper portion of the 21.

3 and 4, the active matrix 21 may include a pad 22 formed on one side of the active matrix 21, an active matrix 21, and a protective layer 23 stacked on the pad 22. ), An etch stop layer 25 formed on the passivation layer 23, and a plug 24 formed vertically from the surface of the etch stop layer 25 to the pad 22 through the passivation layer 23. do.

The two first actuating parts 37 and 38 are respectively in contact with the etch stop layer 25, and the other side thereof is stacked in parallel with the etch stop layer 25 via the first air gap 26. The lower electrode 31, the first lower membrane 29 formed at the lower end of the lower electrode 31, the deformable part 33 formed on the lower electrode 31, and the upper part of the deformable part 33. It consists of an upper electrode 35 formed in.

The second actuating part 41 includes a lower electrode 31, a deformable part 33, an upper electrode 35, a first upper membrane 39, and a mirror 43. The lower electrode 31, the deformable part 33, and the upper electrode 35 of the second actuating part 41 are respectively the lower electrode 31 and the deformable part of the first actuating parts 37 and 38. 33) and members formed integrally with the upper electrode 35. The first upper membrane 39 of the second actuating part 41 is stacked on the upper electrode 35. In addition, a central portion is in contact with an upper portion of the upper electrode 35 of the second actuating portion 41, and one side of the second actuating portion 41 is disposed in parallel with the first upper membrane 39 via the second air gap 42. 43) is formed. The mirror 43 is formed of a flat plate having a groove having a 'U' shape in a central portion, and one side of the mirror 43 covers the first upper membrane 39 and the other side covers a portion of an adjacent actuator. Also, referring to FIGS. 3 and 5, the two first actuating parts 37 and 38 and the second actuating part 41 are formed together with a 'W' shape on the same plane to form an actuator. Configure.

Hereinafter, a manufacturing process of the thin film type optical path control device according to the present embodiment will be described with reference to the drawings.

Referring to FIG. 6A, a pad 22 is formed on an active matrix 21 in which an M × N (M, N is an integer) MOS transistor (not shown) is formed. The pad 22 is made of tungsten or the like and is electrically connected to the MOS transistor embedded in the active matrix 21. A protective layer 23 composed of Phosphor Silicate Glass (PSG) is laminated on the active matrix 21 and the pad 22. The protective layer 23 is formed to have a thickness of about 1.0 to about 2.0 μm using a chemical vapor deposition (CVD) method. The protective layer 23 prevents the active matrix 21 from being damaged from subsequent processes. The etch stop layer 25 is deposited to have a thickness of about 2000 kPa on the upper portion of the protective layer 23 by using a low pressure chemical vapor deposition (LPCVD) method. The etch stop layer 25 prevents the active matrix 21 from being etched and damaged when etching the sacrificial layer 27 formed later. Subsequently, after etching the portion of the anti-etching layer 25 and the protective layer 23 on which the pads 22 are formed, the metal, such as tungsten or titanium, is plugged using a lift-off method. To form (24). The plug 24 is electrically connected to the pad 22 to transfer the image signal generated from the transistor embedded in the active matrix 21 to the lower electrode 31.

Silicate glass (PSG) on top of the etch stop layer 25 and the plug 24 to have a thickness of about 1.0 ~ 2.0㎛ by using the Atmospheric Pressure CVD (APCVD) method. The sacrificial layer 27 is laminated. In this case, the sacrificial layer 27 made of in-silicate glass (PSG) covers the upper portion of the active matrix 21 in which the MOS transistor is embedded, so that the surface flatness is very poor. Accordingly, the surface of the sacrificial layer 27 is planarized by using a spin on coating (SOG) method or a chemical mechanical polishing (CMP) method. Subsequently, a portion of the sacrificial layer 27 is etched to expose a portion where the plug 24 is formed in the etch stop layer 25.

Referring to FIG. 6B, a first lower membrane 29 made of nitride is stacked on one side of the sacrificial layer 27. The first lower membrane 29 has a thickness of about 1.0 to 1.0 μm using a low pressure chemical vapor deposition (LPCVD) method on the sacrificial layer 27 except for the portion where the etch stop layer 25 is exposed. Form to have.

Subsequently, the lower electrode 31 is stacked such that one side contacts the exposed portion of the etch stop layer 25 and the other side contacts the upper portion of the first lower membrane 29. The lower electrode 31 is formed to have a thickness of about 500 to 2000 micrometers by using a sputtering method of platinum (Pt) or titanium (Ti). Accordingly, the lower electrode 31 is electrically connected to the transistor embedded in the active matrix 21 through the pad 22 and the plug 24.

Referring to FIG. 6C, the deformation part 33 is stacked on the lower electrode 27. The deformable portion 33 is formed to have a thickness of about 0.01 to 1.0 µm using piezoelectric ceramics such as PZT or PLZT, or electrodistortion ceramics such as PMN. The deformable portion 33 is formed by using a sol-gel method, and then subjected to a phase change by heat treatment using a rapid thermal annealing (RTA) method. The upper electrode 35 is stacked on the deformable portion 33. The upper electrode 35 is formed of a metal having excellent electrical conductivity, such as aluminum or silver, to have a thickness of about 500 to 2000 kW using a sputtering method. In addition, the sacrificial layer 27 is etched by an etching method using hydrogen fluoride (HF) vapor to form a first air gap 26 to complete the first actuating part 37.

In the process of manufacturing the second actuating part 41, except for the process of forming the first lower membrane 29, the lower electrode 31, the deformable part 33, and the upper electrode 35 are stacked. The process is the same as the process of manufacturing the first actuating unit 37. In Figs. 7A to 7B, the same reference numerals are used for the same members as Figs. 6A to 6C.

Referring to FIG. 7A, a first upper membrane 39 is stacked on the upper center of the upper electrode 35. The first upper membrane 39 is formed of the same material as that of the first lower membrane 29 of the first actuating portion 37 by using a low pressure chemical vapor deposition (LPCVD) method. Form to have a thickness of about.

Referring to FIG. 7B, a mirror 43 is formed on one side of the upper electrode 35 to complete the second actuating part 41. The mirror 43 is formed of a metal such as aluminum or silver to have a thickness of about 500 to 1000 mm by using a conventional photolithography method and sputtering method. The mirror 43 is in the form of a flat plate formed with a 'U' shaped groove in the center. The mirror 43 has a central portion in contact with an upper portion of one side of the upper electrode 35, and one side thereof is formed to be parallel to the first upper membrane 39 via the second air gap 42. The mirror 43 has a shape of a flat plate having a U-shaped groove in a central portion thereof, and is formed to cover a portion of the first upper membrane 39 and an adjacent actuator.

In the above-described thin film type optical path control device according to the present embodiment, an image signal generated from a MOS transistor (not shown) embedded in the active matrix 21 is applied to the lower electrode 31, and to the upper electrode 35. A bias voltage is applied. Therefore, an electric field is generated between the upper electrode 35 and the lower electrode 31. The deformation part 33 between the upper electrode 35 and the lower electrode 31 causes deformation by this electric field. The deformable portion 33 contracts in a direction perpendicular to the electric field, thereby causing the first actuating portions 37 and 38 to deform with a driving angle of θ. The first actuating parts 37 and 38 are bent in the opposite direction to the direction in which the first lower membrane 29 is formed. Further, when the image signal generated from the MOS transistor in the active matrix 21 is applied to the lower electrode 31 and the bias voltage is applied to the upper electrode 35, the deformable portion 33 of the second actuating portion 41 is applied. Contraction occurs in the direction perpendicular to the electric field. Accordingly, the second actuating part 41 also causes deformation with a driving angle of θ. The second actuating portion 41 is bent in a direction opposite to the direction in which the first upper membrane 39 is formed. The driving angles of the first actuating parts 37 and 38 and the second actuating part 41 are the same in magnitude and the driving directions are opposite to each other. Therefore, the sum of the driving angles of the first actuating parts 37 and 38 and the second actuating part 41 is 2θ. Since the mirror 43 reflecting the light beam incident from the light source is formed on the second actuating part 41, the mirror 43 is driven with a driving angle of 2θ.

Example 2

FIG. 8 is a plan view showing a thin film type optical path adjusting device according to a second embodiment of the present invention. FIG. 9 is a sectional view taken along line ee ′ of the device shown in FIG. 8, and FIG. The cross-sectional view which cut | disconnected the apparatus shown by the ff 'line is shown. 8 is a cross-sectional view of the apparatus shown in FIG. 8 taken along the line d-d '. In Figs. 8, 9 and 10, the same reference numerals are used for the same members as Figs. 3, 4 and 5.

Referring to FIG. 8, the thin film type optical path adjusting device according to the present embodiment includes an active matrix 21, two third actuating parts 45 and 46 formed on both sides of the active matrix 21, and an active matrix ( A fifth actuating part 51 integrally formed with the two third actuating parts 45 and 46 and a third actuating part 45 and 46 and a first part in a central upper portion of the 21; Two fourth actuating parts 49 formed integrally with the two third actuating parts 45 and 46 and the fifth actuating part 51 between the five actuating parts 51 ( 50). Accordingly, the third actuating parts 45 and 46, the fourth actuating parts 49 and 50, and the fifth actuating part 51 may be 'U', 'T', on the same plane. In addition, the 'U' has a shape in which it is coupled in turn.

In the present embodiment, the configuration and manufacturing method of the third actuating parts 45 and 46 is a first actuating part according to the first embodiment of the present invention shown in Figs. 4 and 6a to 6c. Same as (37). In addition, the fourth actuating part 49 according to the present embodiment shown in FIG. 9 is the second actuating part shown in FIGS. 5 and 7A to 7B except that the mirror 43 is formed on the upper portion. The composition 41 and its construction and manufacturing method are the same.

8 and 9, the fourth actuating parts 49 and 50 according to the present exemplary embodiment may include the lower electrode 31 and the deformable part of the third actuating parts 45 and 46. 33) and a lower electrode 31, a deformable portion 33, and an upper electrode 35, which are integrally formed with the upper electrode 35. The second upper membrane 47 is stacked on the upper electrode 35. The construction and manufacturing method of the second upper membrane 47 is the same as the first upper membrane 39 of the second actuating portion 41 according to the first embodiment of the present invention shown in FIG. 7A.

8 and 10, the fifth actuating part 51 according to the present embodiment includes the third actuating parts 45 and 46 and the fourth actuating parts 49 and 50. The lower electrode 31, the deformable part 33, and the lower electrode 31, the deformable part 33, and the upper electrode 35 formed integrally with the upper electrode 35, respectively. As shown in FIG. 10, the fifth actuating part 51 has a first actuating part 37 according to the first embodiment of the present invention, except that a mirror 43 is formed on the upper part of the fifth actuating part 51. The configuration and manufacturing method are the same.

A third lower membrane 55, which is the same as the first lower membrane 29 of the first actuating unit 37, is formed at a lower end of the lower electrode 33 of the fifth actuating unit 51. The material and the manufacturing method of the third lower membrane 55 are the same as the first lower membrane 29 of the first actuating portion 37 according to the first embodiment. A mirror 43 is formed on one side of the upper electrode 35 of the fifth actuating part 51. The material and the manufacturing method of the mirror 43 are the same as the mirror 43 of the second actuating part 41 according to the first embodiment shown in FIG.

In the above-described thin film type optical path control device according to the present embodiment, a process in which the deformation part 33 causes deformation by generating an electric field is the same as in the first embodiment. Therefore, the deformable portion 33 of the third actuating parts 45 and 46 contracts in a direction perpendicular to the electric field, so that the third actuating parts 45 and 46 are driven at a driving angle of θ. To cause deformation. The third actuating parts 45 and 46 are bent in a direction opposite to the direction in which the second lower membrane 53 is formed. At the same time, the deformation part 33 of the fourth actuating parts 49 and 50 also causes contraction in the direction perpendicular to the electric field. Accordingly, the fourth actuating parts 49 and 50 also cause deformation with a driving angle of θ. The fourth actuating parts 49 and 50 are bent in the opposite direction to the direction in which the second upper membrane 47 is formed. In addition, the deformation part 33 of the fifth actuating part 51 also causes deformation. Therefore, the fifth actuating part 51 also causes deformation with a driving angle of θ. The fifth actuating part 51 is bent in the opposite direction to the direction in which the third lower membrane 55 is formed. The magnitude and the driving direction of the driving angles of the third actuating parts 45 and 46 and the fifth actuating part 51 are the same. In contrast, the fourth actuating parts 49 and 50 have the same driving angle but the driving direction is the same as the driving direction of the third actuating parts 45 and 46 and the fifth actuating part 51. In the opposite direction. Therefore, the sum of the driving angles of the third actuating parts 45 and 46, the fourth actuating parts 49 and 50, and the fifth actuating part 51 is 3θ. Since the mirror 43 reflecting the light beam incident from the light source is formed on the fifth actuator 51, the mirror 43 is driven at a driving angle of 3θ.

When the same method as the first and second embodiments of the present invention is applied, a thin film type optical path control device having a driving angle of 4θ can be made by being composed of seven actuators. Moreover, the thin film type optical path adjusting device having the driving angle of 5θ can be manufactured by being composed of nine actuating parts, and the thin film type optical path adjusting device having the larger driving angle can be manufactured by being composed of more actuators in the above manner. The device may be manufactured.

Therefore, the thin film type optical path adjusting device according to the present invention described above can drive the mirror with a driving angle of 2 to 3 times or more as compared with the optical path adjusting device described in the preceding application while having a narrow area. Therefore, the light efficiency of the light beam incident from the light source can be increased, and the contrast can be improved to form a bright and clear image. Also, in the design of the system, it is possible to facilitate the design of the system by widening the distance between the light source and the screen.

As mentioned above, although the present invention has been described and illustrated in detail by the preferred embodiments, the present invention is not limited thereto, and it is possible for a person skilled in the art to modify or improve the present invention within a normal range. .

Claims (15)

An active matrix 21 in which M × N (M and N are integer) transistors are formed and a pad 22 is formed on one side; And (B) lower electrodes 31 stacked on one side of the active matrix 21 and parallel to the active matrix 21 via the first air gap 26; 31) a deformable portion 33 stacked on top of each other, and iii) at least two actuating portions each including an upper electrode 35 stacked on top of the deformable portion 33 and driven in opposite directions. Thin film type optical path control device comprising an actuator having. 2. The active matrix 21 according to claim 1, wherein the active matrix 21 is: i) a protective layer 23 stacked on top of the active matrix 21 and the pad 22; And a plug 24 formed perpendicularly from the etch stop layer 25 to the pad 22 through the etch stop layer 25 and the protective layer 23. Thin film type optical path control device characterized in that. The actuator of claim 1, wherein the actuator has two first lower membranes 29 stacked in parallel with the etch stop layer 25 via a first air gap 26 at a lower end of the lower electrode 31. The thin film type optical path control device further comprises a first actuating part (37) (38). 4. The actuator of claim 3, wherein the actuator has a first upper membrane 39 stacked on the upper electrode 35, a central portion in contact with an upper portion of one side of the upper electrode 35, and the second air gap ( And a second actuating portion (41) having a mirror (43) formed to be parallel to the first upper membrane (39) via the thin film type optical path control device. 5. The thin film type optical path adjusting device according to claim 4, wherein the mirror (43) is formed of a flat plate having a 'U' shaped groove in the center portion. 5. The thin film type optical path adjusting device according to claim 4, wherein the mirror (43) is made of silver (Ag) or aluminum (Al). The method of claim 4, wherein the first actuating parts 37 and 38 are formed on both sides of the active matrix 21 with the first lower membrane 29, and the second actuating part ( 41 is formed integrally with the first actuating parts 37 and 38 on the center of the active matrix 21 with the first upper membrane 39 and the mirror 43. Thin film type optical path control device. 8. The apparatus of claim 7, wherein the first actuating parts (37) (38) and the second actuating part (41) together have a 'W' shape on the same plane. 9. The apparatus of claim 8, wherein the first actuating parts (37) and the second actuating part (41) are driven in opposite directions. 2. The actuator of claim 1, wherein each of the actuators has a second lower membrane 53 stacked in parallel with the etch stop layer 25 via a first air gap 26 at a lower end of the lower electrode 31. Thin film type optical path control device further comprises three third actuating portion (45) (46). 11. The actuator of claim 10, wherein the actuator further comprises two fourth actuating parts (49) (50), each having a second upper membrane (47) stacked on top of the upper electrode (35). Thin film type optical path control device. The upper electrode of claim 11, wherein the actuator is stacked in parallel with the etch stop layer 25 via a first air gap 26 at a lower end of the lower electrode 31. The thin film type optical path control device, characterized in that it further comprises a fifth actuating part (51) having a mirror (43) formed in parallel with the upper electrode (35) on one side of the upper portion of the upper side (35). The method of claim 12, wherein the third actuating parts 45 and 46 are formed on both sides of the active matrix 21, and the fifth actuating part 51 is formed on the active matrix 21. It is formed integrally with the third actuating parts 45 and 46 at the center, and the fourth actuating parts 49 and 50 are connected to the third actuating parts 45 and 46. Thin film type optical path control device, characterized in that formed between the fifth actuator (51) and the third actuator (45) (46) and the fifth actuator (51) integrally. 13. The method of claim 12 wherein the third actuating portions 45, 46, the fourth actuating portions 49, 50, and the fifth actuating portion 51 are together coplanar '. A thin film type optical path control device having a shape in which a U 'letter, a' T 'letter, and a' U 'letter are sequentially combined. The driving mechanism of claim 12, wherein the third actuating parts 45 and 46 and the fifth actuating part 51 and the fourth actuating parts 49 and 50 are driven in opposite directions. Thin film type optical path control device, characterized in that.