TWI782053B - Optical device - Google Patents

Abstract

The optical device of the present invention has: a base, which has a main surface; a movable part, which has an optical function part; The method of moving in the first vertical direction supports the movable part. The elastic supporting part has: a rod; a first twist supporting part extending along a second direction perpendicular to the first direction and connected between the rod and the movable part; and a second twist supporting part extending along the second direction Extended and connected between the rod and the base. The torsional spring constant of the first torsion support part is larger than the torsion spring constant of the second torsion support part.

Description

optical device

The present invention relates to an optical device configured, for example, as a MEMS (Micro Electro Mechanical Systems) device.

As a MEMS device, there is known an optical device comprising: a base; a movable part having an optical function part; The movable part is supported in a movable manner (for example, refer to Patent Document 1). In such an optical device, there may be cases where the elastic support portion includes a twist support portion that is twisted and deformed when the movable portion moves along the movement direction.

Prior art literature patent documents

Patent Document 1: Specification of U.S. Patent Application Publication No. 2008/0284078

In the optical device as described above, a configuration is considered in which the width of the twist support portion is reduced so that the twist support portion can be easily twisted so that the movable portion can move largely in the moving direction. However, in such a configuration, when the shape of the torsion support portion is deviated due to manufacturing errors or the like, the movable portion is inclined from the target posture when the movable portion moves in the moving direction, and as a result, the optical characteristics may be degraded.

The object of the present invention is to provide a method that can suppress the shape of the support part from twisting. Optical devices with reduced optical properties caused by unevenness.

An optical device according to an aspect of the present invention includes: a base having a main surface; a movable part having an optical function part; and an elastic supporting part connected between the base and the movable part, and the movable part can The movable part is supported by moving in the first direction perpendicular to the main surface; the elastic support part has: a rod; the first twist support part extends along the second direction perpendicular to the first direction, and is connected to the rod and the movable part Between; and the second torsion support part, which extends along the second direction and is connected between the rod and the base; the torsional spring constant of the first torsion support part is greater than the torsion spring constant of the second torsion support part.

In this optical device, the torsional spring constant of the first torsion supporting part connected between the rod and the movable part is larger than the torsional spring constant of the second torsion supporting part connected between the rod and the base. Thereby, even when the shape of at least one of the first torsion support portion and the second torsion support portion deviates due to manufacturing errors or the like, it is possible to suppress the movable portion from the target posture when the movable portion moves in the first direction. tilt. Therefore, according to this optical device, it is possible to suppress a reduction in optical characteristics caused by variations in the shape of the twist support portion.

In the optical device according to one aspect of the present invention, when viewed from the first direction, the width of the first twist supporting portion may be wider than the width of the second twist supporting portion. In this case, it is preferable to make the torsional spring constant of the first torsion support part larger than the torsion spring constant of the second torsion support part.

In the optical device according to an aspect of the present invention, when viewed from the first direction, the length of the first twist supporting portion may be shorter than the length of the second twist supporting portion. In this case, the torsional spring constant of the first torsion support portion can be further preferably made larger than the torsion spring constant of the second torsion support portion.

In the optical device according to an aspect of the present invention, the base, the movable part, and the elastic support part may also be formed of an SOI (Silicon On Insulator, silicon-on-insulator) substrate. In this case, in the optical device formed by the MEMS technology, it is possible to suppress a decrease in optical characteristics caused by unevenness in the shape of the twist support portion.

The optical device according to one aspect of the present invention may further include: a fixed comb-tooth electrode provided on the base and having a plurality of fixed comb-tooth electrodes; and a movable comb-tooth electrode provided on the above-mentioned movable part and the above-mentioned elastic support part At least one of them has a plurality of movable comb teeth arranged alternately with the plurality of fixed comb teeth. In this case, the actuator unit for moving the movable unit can be simplified and power consumption can be reduced.

An optical device according to an aspect of the present invention may only have a pair of elastic supporting parts. In this case, for example, compared with the case where only one elastic supporting part is provided, the movement of the movable part can be stabilized. Also, for example, the total number of torsion support parts can be reduced compared to the case where three or more elastic support parts are provided. As a result, the spring constant of each torsion support portion can be ensured, and it is less likely to be affected by variations in the shape of the torsion support portion.

According to an aspect of the present invention, it is possible to provide an optical device capable of suppressing a decrease in optical characteristics caused by variations in the shape of the twist support portion.

1: Optical module

2: mirror unit

3: Beam splitter unit

4: Optical resin

10: Optical device

11: Movable mirror (movable part)

11a: mirror surface (optical function department)

12: base

12a: main surface

12b: main surface

12c: opening

13: Drive Department

14: The first elastic support department

15: The second elastic support department

16:Actuator part

17: The first optical function department

18: The second optical function department

21: fixed mirror

21a: mirror surface

22: Support body

22a: surface

22c: surface

23: Sub-installation substrate

24: Encapsulation

25: Lead pin

26: wire

31: Semi-reflective mirror surface

32: Total reflection mirror

33a: Optical surface

33b: Optical surface

33c: Optical surface

33d: optical surface

50: SOI substrate

51: Support layer

52: Device layer

53: middle layer

111: body part

112: frame part

112a: the second body part

112b: The second beam part

113: linking part

113a: The third body part

113b: The third beam part

114: central part

115: Outer edge

115a: the first body part

115b: The first beam part

116: Bracket

117: Bracket

121: electrode pad

122: electrode pad

141: Rod

141a: end

141b: end

141c: protrusion

142: Connecting rod

143: Connecting rod

144: Bracket

145: The first torsion bar (the first torsion support part)

146: The second torsion bar (the second torsion support part)

147: electrode support part

151: Rod

151a: end

151b: end

151c: protrusion

152: Connecting rod

153: Connecting rod

154: Bracket

155: The first torsion bar (the first torsion support part)

156: The second torsion bar (the second torsion support part)

157: electrode support part

161: fixed comb electrode

161a: fixed comb teeth

162: Movable comb electrode

162a: Movable comb teeth

163: fixed comb electrode

163a: fixed comb teeth

164: Movable comb electrode

164a: Movable comb teeth

241: bottom wall

242: side wall

243: top wall

243a: surface

L0: measuring light

L1: measuring light

P1: optical path

P2: light path

R1: axis

R2: axis

S: space

Fig. 1 is a longitudinal sectional view of an optical module provided with an optical device according to an embodiment.

FIG. 2 is a top view of the optical device shown in FIG. 1 .

Fig. 3 is an enlarged plan view of a part of Fig. 2 .

Fig. 4 is a sectional view along line IV-IV of Fig. 2 .

Fig. 5 is a graph showing the inclination of the mirror surface during movement in Examples and Comparative Examples.

Hereinafter, an embodiment of one aspect of the present invention will be described in detail with reference to the drawings. In addition, in the following description, the same code|symbol is used for the same or equivalent element, and repeated description is abbreviate|omitted.

[Composition of Optical Module]

As shown in FIG. 1 , the optical module 1 includes a mirror unit 2 and a beam splitter unit 3 . The mirror unit 2 has an optical device 10 and a fixed mirror 21 . The optical device 10 includes a movable mirror (movable unit) 11 . In the optical module 1 , the spectroscopic mirror unit 3 constitutes an interference optical system for the measurement light L0 by the movable mirror 11 and the fixed mirror 21 . The interferometric optical system is here a Michelson interferometric optical system.

The optical device 10 includes a base 12 , a drive unit 13 , a first optical function unit 17 , and a second optical function unit 18 in addition to the movable mirror 11 . The base 12 has a main surface 12a. The movable mirror 11 has a mirror surface (optical function part) 11a along a plane parallel to the main surface 12a. The movable mirror 11 is supported by the base 12 so as to be movable along the Z-axis direction (direction parallel to the Z-axis, first direction) perpendicular to the main surface 12a. The driving unit 13 moves the movable mirror 11 along the Z-axis direction. When viewed from the Z-axis direction, the first optical function part 17 is disposed on one side of the movable mirror 11 in the X-axis direction (direction parallel to the X-axis, third direction) perpendicular to the Z-axis direction. The second optical function part 18 is disposed on the other side of the movable mirror 11 in the X-axis direction when viewed from the Z-axis direction. Each of the 1st optical function part 17 and the 2nd optical function part 18 is the light passage opening part provided in the base 12, and it opens to one side and the other side in the Z-axis direction. Furthermore, in the optical module 1, the second optical function part 18 is not used as the light passage opening. When applying the optical device 10 to other devices, at least one of the first optical function part 17 and the second optical function part 18 can be used as an optical function part, or the first optical function part 17 and the second optical function part 17 can be used as optical function parts. 2 Both of the optical function parts 18 are not used as optical function parts.

The fixed mirror 21 has a plane (perpendicular to the Z-axis direction) along a plane parallel to the main surface 12a. plane) extending mirror surface 21a. The position of the fixed mirror 21 relative to the base 12 is fixed. In the mirror unit 2, the mirror surface 11a of the movable mirror 11 and the mirror surface 21a of the fixed mirror 21 face one side in the Z-axis direction (the beam splitter unit 3 side).

The mirror unit 2 includes a support 22 , a submount substrate 23 , and a package 24 in addition to the optical device 10 and the fixed mirror 21 . The package 24 accommodates the optical device 10 , the fixed mirror 21 , the support 22 and the submount substrate 23 . The package body 24 includes a bottom wall 241 , a side wall 242 and a top wall 243 . The package 24 is formed in, for example, a rectangular parallelepiped box shape. The package body 24 has a size of about 30×25×10 (thickness) mm, for example. The bottom wall 241 and the side wall 242 are formed integrally with each other. The top wall 243 is opposite to the bottom wall 241 along the Z-axis direction, and is fixed to the side wall 242 . The top wall 243 is transparent to the measurement light L0. In the mirror unit 2 , a space S is formed by the package body 24 . The space S is opened to the outside of the mirror unit 2 through, for example, a vent hole or a gap provided in the package body 24 . When the space S is not an airtight space, it is possible to suppress contamination or staining of the mirror surface 11a caused by outgassing of the resin material in the package 24 or moisture in the package 24 . Furthermore, the space S may be an airtight space maintained at a relatively high degree of vacuum, or an airtight space filled with an inert gas such as nitrogen.

On the inner surface of the bottom wall 241 , the support body 22 is fixed via the spacer mounting substrate 23 . The support body 22 is formed in, for example, a rectangular plate shape. The support 22 has translucency with respect to the measurement light L0. The base 12 of the optical device 10 is fixed on the surface 22 a of the support 22 opposite to the submount substrate 23 . That is, the base 12 is supported by the support body 22 . A recess 22 b is formed on the surface 22 a of the support 22 , and a gap (part of the space S) is formed between the optical device 10 and the top wall 243 . Thereby, when the movable mirror 11 moves along the Z-axis direction, the movable mirror 11 and the driving part 13 are prevented from contacting the supporting body 22 and the top wall 243 .

In the submount substrate 23, an opening 23a is formed. The fixed mirror 21 is located in the open The inside of the opening 23a is disposed on the surface 22c of the support 22 on the side of the sub-mount substrate 23 . That is, the fixed mirror 21 is disposed on the surface 22 c of the support body 22 opposite to the base 12 . When viewed from the Z-axis direction, the fixed mirror 21 is disposed on one side of the movable mirror 11 in the X-axis direction. When viewed from the Z-axis direction, the fixed mirror 21 overlaps the first optical function part 17 of the optical device 10 .

The mirror unit 2 further has a plurality of lead pins 25 and a plurality of wires 26 . Each lead pin 25 is fixed on the bottom wall 241 in a state of penetrating the bottom wall 241 . Each lead pin 25 is electrically connected to the driving part 13 via a wire 26 . In the mirror unit 2 , electrical signals for moving the movable mirror 11 along the Z-axis direction are given to the drive unit 13 through a plurality of lead pins 25 and a plurality of wires 26 .

The beam splitter unit 3 is supported by the top wall 243 of the package body 24 . Specifically, the spectroscopic mirror unit 3 is fixed on the surface 243 a of the top wall 243 opposite to the optical device 10 by the optical resin 4 . The optical resin 4 has translucency with respect to the measurement light L0.

The spectroscopic mirror unit 3 has a half reflection mirror surface 31, a total reflection mirror surface 32 and a plurality of optical surfaces 33a, 33b, 33c, 33d. The spectroscopic mirror unit 3 is constituted by bonding a plurality of optical blocks. The half mirror surface 31 is formed by, for example, a dielectric multilayer film. The total reflection mirror surface 32 is formed by, for example, a metal film.

The optical surface 33a is, for example, a surface perpendicular to the Z-axis direction, and overlaps the first optical function part 17 of the optical device 10 and the mirror surface 21a of the fixed mirror 21 when viewed from the Z-axis direction. The optical surface 33a transmits the measurement light L0 incident along the Z-axis direction.

The half mirror surface 31 is, for example, a surface inclined at 45 degrees relative to the optical surface 33a, and overlaps the first optical function part 17 of the optical device 10 and the mirror surface 21a of the fixed mirror 21 when viewed from the Z-axis direction. The half mirror surface 31 makes the measurement light incident on the optical surface 33a along the Z-axis direction A part of L0 is reflected along the X-axis direction, and the rest of the measurement light L0 is transmitted through the fixed mirror 21 side along the Z-axis direction.

The total reflection mirror surface 32 is a surface parallel to the half reflection mirror surface 31, and overlaps the mirror surface 11a of the movable mirror 11 when viewed from the Z-axis direction and overlaps the half-reflection mirror surface 31 when viewed from the X-axis direction. The total reflection mirror surface 32 reflects a part of the measurement light L0 reflected by the half reflection mirror surface 31 to the side of the movable mirror 11 along the Z-axis direction.

The optical surface 33b is a surface parallel to the optical surface 33a, and overlaps the mirror surface 11a of the movable mirror 11 when viewed from the Z-axis direction. The optical surface 33b allows a part of the measurement light L0 reflected by the total reflection mirror surface 32 to pass through the movable mirror 11 side along the Z-axis direction.

The optical surface 33c is a surface parallel to the optical surface 33a, and overlaps the mirror surface 21a of the fixed mirror 21 when viewed from the Z-axis direction. The optical surface 33c allows the rest of the measurement light L0 transmitted through the half mirror surface 31 to pass through the fixed mirror 21 side along the Z-axis direction.

The optical surface 33d is, for example, a surface perpendicular to the X-axis direction, and overlaps the half-reflection mirror surface 31 and the total reflection mirror surface 32 when viewed from the X-axis direction. The optical surface 33d transmits the measurement light L1 along the X-axis direction. The measurement light L1 is a part of the measurement light L0 which is sequentially reflected by the mirror surface 11a of the movable mirror 11 and the total reflection mirror surface 32 and passes through the half reflection mirror surface 31, and the measurement light L0 which is sequentially reflected by the mirror surface 21a of the fixed mirror 21 and the half reflection mirror surface 31 The rest of the interference light.

In the optical module 1 configured as above, if the measurement light L0 enters the spectroscopic mirror unit 3 from the outside of the optical module 1 through the optical surface 33a, a part of the measurement light L0 is reflected by the semi-reflective mirror surface 31 and the total reflection. The mirror surface 32 is sequentially reflected and then moves toward the mirror surface 11a of the movable mirror 11 . Then, part of the measurement light L0 is reflected by the mirror surface 11 a of the movable mirror 11 , travels in the opposite direction on the same optical path (optical path P1 described below), and passes through the half mirror surface 31 of the beam splitter unit 3 .

On the other hand, the rest of the measurement light L0 passes through the half reflection of the beam splitter unit 3 After entering the mirror surface 31, it passes through the first optical function part 17, and then passes through the support body 22, and then advances toward the mirror surface 21a of the fixed mirror 21. Then, the rest of the measurement light L0 is reflected by the mirror surface 21 a of the fixed mirror 21 , travels in the opposite direction on the same optical path (optical path P2 described below), and is reflected by the half-reflective mirror surface 31 of the beam splitter unit 3 .

Part of the measurement light L0 passing through the half-reflection mirror surface 31 of the spectroscope unit 3 and the remaining part of the measurement light L0 reflected by the half-reflection mirror surface 31 of the spectroscope unit 3 become interference light, that is, measurement light L1, and the measurement light L1 passes through the spectroscope. The unit 3 emits to the outside of the optical module 1 through the optical surface 33d. According to the optical module 1, since the movable mirror 11 can be reciprocated at high speed along the Z-axis direction, a compact and high-precision FTIR (Fourier Transform infrared spectroscopy) can be provided.

The supporting body 22 corrects the optical path difference between the optical path P1 between the beam splitter unit 3 and the movable mirror 11 and the optical path P2 between the beam splitter unit 3 and the fixed mirror 21 . Specifically, the optical path P1 is an optical path from the semi-reflective mirror surface 31 to the mirror surface 11a of the movable mirror 11 at the reference position via the total reflection mirror surface 32 and the optical surface 33b sequentially, and is an optical path through which a part of the measurement light L0 advances. The optical path P2 is an optical path from the semireflective mirror surface 31 to the mirror surface 21a of the fixed mirror 21 through the optical surface 33c and the first optical function part 17 sequentially, and is an optical path through which the rest of the measurement light L0 advances. The support body 22 is based on the optical path length of the optical path P1 (considering the optical path length of the refractive index of the medium that the optical path P1 passes through) and the optical path length of the optical path P2 (considering the optical path length of the refractive index of the various media that the optical path P2 passes through) In such a way that the difference becomes smaller (for example, disappears), the optical path difference between the optical path P1 and the optical path P2 is corrected. Furthermore, the support body 22 can be formed of the same translucent material as that of each optical block constituting the beam splitter unit 3 , for example. In this case, the thickness (length in the Z-axis direction) of the support 22 may be the same as the distance between the half-reflection mirror surface 31 and the total reflection mirror surface 32 in the X-axis direction.

[Structure of optical device]

As shown in Fig. 2, Fig. 3 and Fig. 4, the part other than the mirror surface 11a, the base 12, the driving part 13, the first optical function part 17 and the second optical function part 18 in the movable mirror 11 are made by SOI (Silicon On Insulator) substrate 50. That is, the optical device 10 is constituted by the SOI substrate 50 . The optical device 10 is formed in, for example, a rectangular plate shape. The optical device 10 has a size of about 15×10×0.3 (thickness) mm, for example. The SOI substrate 50 has a support layer 51 , a device layer 52 and an intermediate layer 53 . The supporting layer 51 is the first silicon layer. The device layer 52 is the second silicon layer. The intermediate layer 53 is an insulating layer disposed between the supporting layer 51 and the device layer 52 .

The submount 12 is formed by a support layer 51 , a device layer 52 and a part of an intermediate layer 53 . The main surface 12 a of the base 12 is the surface on the opposite side to the intermediate layer 53 in the device layer 52 . The main surface 12 b of the base 12 opposite to the main surface 12 a is the surface of the supporting layer 51 opposite to the intermediate layer 53 . In the optical module 1, the main surface 12a of the base 12 and the surface 22a of the support 22 are bonded to each other (see FIG. 1).

The movable mirror 11 is arranged with the intersection point of the axis R1 and the axis R2 as a center position (center of gravity position). The axis R1 is a straight line extending in the X-axis direction. The axis R2 is a straight line extending in the Y-axis direction (the direction parallel to the Y-axis, the second direction) perpendicular to the X-axis direction and the Z-axis direction. When viewed from the Z-axis direction, the optical device 10 has a shape that is line-symmetric to the axis R1 and line-symmetric to the axis R2.

The movable mirror 11 has a body portion 111 , a frame portion 112 and a pair of connecting portions 113 . The main body part 111 has a circular shape when viewed from the Z-axis direction. The main body portion 111 has a central portion 114 and an outer edge portion 115 . On the surface on the main surface 12b side of the central portion 114, for example, a circular mirror surface 11a is provided by forming a metal film. The central portion 114 is formed by a portion of the device layer 52 . The outer edge portion 115 surrounds the central portion 114 when viewed from the Z-axis direction. The outer edge portion 115 has a first body portion 115a and a first beam portion 115b. The first body part 115a is connected by the device layer 52 formed as part of it.

The first beam portion 115 b is formed by a part of the supporting layer 51 and the intermediate layer 53 . The first beam portion 115b is provided on the surface on the main surface 12b side of the first main body portion 115a. The first beam portion 115b is formed such that the thickness of the outer edge portion 115 in the Z-axis direction is thicker than the thickness of the central portion 114 in the Z-axis direction. When viewed from the Z-axis direction, the first beam portion 115b has an annular shape and surrounds the mirror surface 11a. When viewed from the Z-axis direction, the first beam portion 115 b extends along the outer edge of the main body portion 111 . In this embodiment, when viewed from the Z-axis direction, the outer edge of the first beam portion 115b extends along the outer edge of the main body portion 111 at a certain interval from the outer edge of the main body portion 111 . When viewed from the Z-axis direction, the inner edge of the first beam portion 115b extends along the outer edge of the mirror surface 11a at a certain interval from the outer edge of the mirror surface 11a.

When viewed from the Z-axis direction, the frame portion 112 surrounds the body portion 111 with a certain interval from the body portion 111 . The frame portion 112 is annular when viewed from the Z-axis direction. The frame part 112 has the 2nd main body part 112a and the 2nd beam part 112b. The second body portion 112 a is formed by a part of the device layer 52 .

The second beam portion 112b is formed by a part of the supporting layer 51 and the intermediate layer 53 . The second beam portion 112b is provided on the surface on the main surface 12b side of the second main body portion 112a. The second beam portion 112b is formed such that the thickness of the frame portion 112 in the Z-axis direction is thicker than the thickness of the center portion 114 in the Z-axis direction. When viewed from the Z-axis direction, the second beam portion 112b has an annular shape. When viewed from the Z-axis direction, the outer edge of the second beam portion 112b extends along the outer edge of the frame portion 112 at a certain interval from the outer edge of the frame portion 112 . When viewed from the Z-axis direction, the inner edge of the second beam portion 112b extends along the inner edge of the frame portion 112 at a predetermined interval from the inner edge of the frame portion 112 .

The thickness of the second beam portion 112b in the Z-axis direction and the thickness of the first beam portion in the Z-axis direction The thickness of 115b is equal. When viewed from the Z-axis direction, the width of the second beam portion 112b is wider than the width of the first beam portion 115b. The so-called width of the first beam portion 115b when viewed from the Z-axis direction refers to the length of the first beam portion 115b in a direction perpendicular to the extending direction of the first beam portion 115b. In this embodiment, it is the length of the first beam portion 115b. 1 Length of the first beam portion 115b in the radial direction of the beam portion 115b. In this respect, the same applies to the width of the second beam portion 112b when viewed from the Z-axis direction.

Each of the pair of connecting parts 113 connects the main body part 111 and the frame part 112 to each other. The pair of connecting parts 113 are respectively disposed on one side and the other side in the Y-axis direction with respect to the main body part 111 . Each connection part 113 has the 3rd main body part 113a and the 3rd beam part 113b. The third body portion 113 a is formed by a part of the device layer 52 . The third body part 113a is connected to the first body part 115a and the second body part 112a.

The third beam portion 113b is formed by a part of the support layer 51 and the intermediate layer 53 . The third beam portion 113b is connected to the first beam portion 115b and the second beam portion 112b. The third beam portion 113b is provided on the surface on the main surface 12b side of the third main body portion 113a. The third beam portion 113b is formed such that the thickness of the connection portion 113 in the Z-axis direction is thicker than the thickness of the central portion 114 in the Z-axis direction. The thickness of the third beam portion 113b in the Z-axis direction is equal to the thickness of each of the first beam portion 115b and the second beam portion 112b in the Z-axis direction. The width of the 3rd beam part 113b is larger than the width of each of the 1st beam part 115b and the 2nd beam part 112b. The width of the third beam portion 113b refers to the length of the third beam portion 113b along the extending direction of the first beam portion 115b.

The movable mirror 11 further has a pair of brackets 116 and a pair of brackets 117 . Each standoff 116 and each standoff 117 are formed by a portion of the device layer 52 . Each bracket 116 extends along the Y-axis direction, and is rectangular when viewed from the Z-axis direction. One bracket 116 protrudes from the side of the frame portion 112 toward one side in the Y-axis direction, and the other bracket 116 protrudes from the side of the frame portion 112 toward the other side in the Y-axis direction. A pair of brackets 116 are disposed on the same plane parallel to the Y-axis direction. center line. Each holder 116 extends from the end of the frame part 112 on the side of the first optical function part 17 .

Each bracket 117 extends along the Y-axis direction, and is rectangular when viewed from the Z-axis direction. One bracket 117 protrudes from the side of the frame portion 112 toward one side in the Y-axis direction, and the other bracket 117 protrudes from the side of the frame portion 112 toward the other side in the Y-axis direction. The pair of brackets 117 are arranged on the same center line parallel to the Y-axis direction. Each holder 117 extends from an end of the frame portion 112 on the second optical function portion 18 side (opposite side to the first optical function portion 17 ).

The drive unit 13 has a first elastic support unit 14 , a second elastic support unit 15 , and an actuator unit 16 . The first elastic support part 14 , the second elastic support part 15 and the actuator part 16 are formed by the device layer 52 .

Each of the first elastic support part 14 and the second elastic support part 15 is connected between the base 12 and the movable mirror 11 . The first elastic support part 14 and the second elastic support part 15 support the movable mirror 11 so that the movable mirror 11 can move along the Z-axis direction.

The first elastic supporting part 14 has a pair of rods 141, a connecting rod 142, a connecting rod 143, a pair of brackets 144, a pair of first torsion bars (the first torsion supporting part) 145, a pair of the second torsion bars (the second torsion bar) support part) 146, and a pair of electrode support parts 147. The pair of rods 141 are arranged on both sides of the first optical function part 17 in the Y-axis direction. Each rod 141 has a plate shape extending along a plane perpendicular to the Z-axis direction. In this embodiment, each rod 141 extends along the X-axis direction.

The link 142 is spanned between the ends 141 a of the pair of rods 141 on the side of the movable mirror 11 . The link 142 has a plate shape extending along a plane perpendicular to the Z-axis direction. The link 142 extends along the Y-axis direction. The link 143 is spanned between the ends 141 b of the pair of rods 141 on the opposite side to the movable mirror 11 . The link 143 has a plate shape extending along a plane perpendicular to the Z-axis direction, and extends along the Y-axis direction. In this embodiment, the first optical function part 17 is an opening defined by a pair of rods 141 , a link 142 , and a link 143 . When viewed from the Z-axis direction, the first optical function part 17 is rectangular shape. The first optical function part 17 is, for example, a cavity. Alternatively, a material having translucency with respect to the measurement light L0 may be disposed in the opening constituting the first optical function portion 17 .

Each bracket 144 is rectangular when viewed from the Z-axis direction. Each bracket 144 is provided on the surface of the link 142 on the movable mirror 11 side so as to protrude toward the movable mirror 11 side. One bracket 144 is disposed near one end of the connecting rod 142 , and the other bracket 144 is disposed near the other end of the connecting rod 142 .

A pair of first torsion bars 145 are respectively erected between the front end of one bracket 116 and one bracket 144 , and between the front end of the other bracket 116 and the other bracket 144 . That is, the pair of first torsion bars 145 are respectively connected between the pair of rods 141 and the movable mirror 11 . Each first torsion bar 145 extends along the Y-axis direction. The pair of first torsion bars 145 are arranged on the same center line parallel to the Y-axis direction.

A pair of second torsion rods 146 are erected between the end 141b of one rod 141 opposite to the movable mirror 11 and the base 12, and between the end 141b of the other rod 141 opposite to the movable mirror 11 and the other rod 141. Between the base 12. That is, the pair of second torsion bars 146 are respectively connected between the pair of rods 141 and the base 12 . Each second torsion bar 146 extends along the Y-axis direction. The pair of second torsion bars 146 are arranged on the same center line parallel to the Y-axis direction. At the end 141b of each rod 141, a protruding portion 141c protruding outward in the Y-axis direction is provided, and the second torsion bar 146 is connected to the protruding portion 141c.

Each electrode supporting portion 147 extends along the Y-axis direction, and has a rectangular shape when viewed from the Z-axis direction. One electrode support part 147 extends from the middle part of one rod 141 toward the side opposite to the first optical function part 17 . The other electrode support part 147 protrudes from the middle part of the other rod 141 to the side opposite to the first optical function part 17 . When viewed from the Z-axis direction, the pair of electrode support portions 147 are arranged on the same center line parallel to the Y-axis direction.

The 2nd elastic supporting part 15 has a pair of rods 151, a connecting rod 152, a connecting rod 153, a pair of brackets 154, a pair of first torsion bars (the first torsion supporting part) 155, a pair of the second torsion bars (the second torsion bar) support part) 156, and a pair of electrode support parts 157. The pair of rods 151 are arranged on both sides of the second optical function part 18 in the Y-axis direction. Each rod 151 has a plate shape extending along a plane perpendicular to the Z-axis direction. In this embodiment, each rod 151 extends along the X-axis direction.

The link 152 is spanned between the ends 151 a of the pair of rods 151 on the side of the movable mirror 11 . The link 152 has a plate shape extending along a plane perpendicular to the Z-axis direction. The link 152 extends along the Y-axis direction. The link 153 is spanned between the ends 151b of the pair of rods 151 on the opposite side to the movable mirror 11 . The link 153 has a plate shape extending along a plane perpendicular to the Z-axis direction, and extends along the Y-axis direction. In this embodiment, the second optical function part 18 is an opening defined by a pair of rods 151 , a link 152 , and a link 153 . When viewed from the Z-axis direction, the second optical function part 18 has a rectangular shape. The second optical function part 18 is, for example, a cavity. Alternatively, a material having translucency with respect to the measurement light L0 may be disposed in the opening constituting the second optical function portion 18 .

Each bracket 154 is rectangular when viewed from the Z-axis direction. Each bracket 154 is provided on the surface of the link 152 on the movable mirror 11 side so as to protrude toward the movable mirror 11 side. One bracket 154 is disposed near one end of the connecting rod 152 , and the other bracket 154 is disposed near the other end of the connecting rod 152 .

A pair of first torsion bars 155 are respectively erected between the front end of one bracket 117 and one bracket 154 , and between the front end of the other bracket 117 and the other bracket 154 . That is, the pair of first torsion bars 155 are respectively connected between the pair of rods 151 and the movable mirror 11 . Each first torsion bar 155 extends along the Y-axis direction. The pair of first torsion bars 155 are arranged on the same center line parallel to the Y-axis direction.

A pair of the 2nd torsion bar 156 is erected respectively in a bar 151 and movable mirror 11 Between the end 151b on the opposite side and the base 12 , and between the end 151b on the opposite side to the movable mirror 11 of the other rod 151 and the base 12 . That is, the pair of second torsion bars 156 are respectively connected between the pair of rods 151 and the base 12 . Each second torsion bar 156 extends along the Y-axis direction. The pair of second torsion bars 156 are arranged on the same center line parallel to the Y-axis direction. At the end 151b of each rod 151, a protruding portion 151c protruding outward in the Y-axis direction is provided, and the second torsion bar 156 is connected to the protruding portion 151c.

Each electrode supporting portion 157 extends along the Y-axis direction, and has a rectangular shape when viewed from the Z-axis direction. One electrode support part 157 extends from the middle part of one rod 151 toward the side opposite to the second optical function part 18 . The other electrode support part 157 protrudes from the middle part of the other rod 151 to the side opposite to the second optical function part 18 . When viewed from the Z-axis direction, the pair of electrode support portions 157 are arranged on the same center line parallel to the Y-axis direction.

The actuator unit 16 moves the movable mirror 11 along the Z-axis direction. The actuator unit 16 has a pair of fixed comb-shaped electrodes 161 , a pair of movable comb-shaped electrodes 162 , a pair of fixed comb-shaped electrodes 163 , and a pair of movable comb-shaped electrodes 164 . The positions of the fixed comb electrodes 161 and 163 are fixed. The movable comb electrodes 162 and 164 move along with the movement of the movable mirror 11 .

A fixed comb-teeth electrode 161 is disposed on the surface of the device layer 52 of the submount 12 opposite to the electrode supporting portion 147 . Another fixed comb electrode 161 is disposed on the surface of the device layer 52 opposite to the other electrode supporting portion 147 . Each fixed comb-teeth electrode 161 has a plurality of fixed comb-teeth 161a extending along a plane perpendicular to the Y-axis direction. The fixed comb teeth 161a are arranged at specific intervals in the Y-axis direction.

One movable comb electrode 162 is provided on the surface of both sides in the X-axis direction in one electrode supporting portion 147 . Another movable comb electrode 162 is provided on the surface of both sides in the X-axis direction in the other electrode supporting portion 147 . Each movable comb electrode 162 has a direction along the Y axis A plurality of movable comb teeth 162a extending in a vertical plane. The movable comb teeth 162a are arranged at specific intervals in the Y-axis direction.

In one fixed comb-teeth electrode 161 and one movable comb-teeth electrode 162, a plurality of fixed comb teeth 161a and a plurality of movable comb teeth 162a are arranged alternately. That is, each fixed comb tooth 161 a of a fixed comb tooth electrode 161 is located between the movable comb teeth 162 a of a movable comb tooth electrode 162 . In the other fixed comb-teeth electrode 161 and the other movable comb-teeth electrode 162, a plurality of fixed comb teeth 161a and a plurality of movable comb teeth 162a are arranged alternately. That is, each fixed comb-teeth 161 a of the other fixed comb-teeth electrode 161 is located between the movable comb-teeth 162 a of the other movable comb-teeth electrode 162 . Among the pair of fixed comb-teeth electrodes 161 and the pair of movable comb-teeth electrodes 162, the adjacent fixed comb teeth 161a and the movable comb teeth 162a are opposite to each other in the Y-axis direction. The distance between adjacent fixed comb teeth 161a and movable comb teeth 162a is, for example, about several μm.

A fixed comb-teeth electrode 163 is disposed on the surface of the device layer 52 of the submount 12 opposite to the electrode supporting portion 157 . Another fixed comb electrode 163 is disposed on the surface of the device layer 52 opposite to the other electrode supporting portion 157 . Each fixed comb electrode 163 has a plurality of fixed comb teeth 163 a extending along a plane perpendicular to the Y-axis direction. The fixed comb teeth 163a are arranged at specific intervals in the Y-axis direction.

One movable comb electrode 164 is provided on the surface of both sides in the X-axis direction in one electrode support portion 157 . Another movable comb-teeth electrode 164 is provided on the surface of both sides in the X-axis direction in the other electrode support portion 157 . Each movable comb electrode 164 has a plurality of movable comb teeth 164 a extending along a plane perpendicular to the Y-axis direction. The movable comb teeth 164a are arranged at specific intervals in the Y-axis direction.

In one fixed comb-teeth electrode 163 and one movable comb-teeth electrode 164, a plurality of fixed comb teeth 163a and a plurality of movable comb teeth 164a are arranged alternately. That is, a fixed comb Each fixed comb tooth 163 a of the electrode 163 is located between the movable comb teeth 164 a of a movable comb tooth electrode 164 . In the other fixed comb-teeth electrode 163 and the other movable comb-teeth electrode 164, a plurality of fixed comb teeth 163a and a plurality of movable comb teeth 164a are arranged alternately. That is, each fixed comb-teeth 163 a of the other fixed comb-teeth electrode 163 is located between the movable comb-teeth 164 a of the other movable comb-teeth electrode 164 . Among the pair of fixed comb electrodes 163 and the pair of movable comb electrodes 164 , adjacent fixed comb teeth 163 a and movable comb teeth 164 a are opposite to each other in the Y-axis direction. The distance between the fixed comb teeth 163a and the movable comb teeth 164a adjacent to each other is, for example, about several μm.

A plurality of electrode pads 121 , 122 are disposed on the base 12 . Each electrode pad 121 , 122 is formed on the surface of the device layer 52 in the opening 12 c formed on the main surface 12 b of the base 12 so as to reach the device layer 52 . Each electrode pad 121 is electrically connected to the fixed comb-shaped electrode 161 or the fixed comb-shaped electrode 163 via the device layer 52 . Each electrode pad 122 is electrically connected to the movable comb-shaped electrode 162 or the movable comb-shaped electrode 164 via the first elastic support portion 14 or the second elastic support portion 15 . The wires 26 are erected between the electrode pads 121 , 122 and the lead pins 25 .

In the optical device 10 configured as above, if a voltage is applied between the plurality of electrode pads 121 and the plurality of electrode pads 122 through the plurality of lead pins 25 and the plurality of wires 26, for example, in the Z-axis direction The way that the upper side moves the movable mirror 11 is generated between the fixed comb-teeth electrodes 161 and the movable comb-teeth electrodes 162 facing each other, and between the fixed comb-teeth electrodes 163 and the movable comb-teeth electrodes 164 facing each other. electrostatic force. At this time, in the first elastic support part 14 and the second elastic support part 15, each first torsion bar 145, 155 and each second torsion bar 146, 156 are twisted, and the first elastic support part 14 and the second elastic support part 15 produces elastic force. In the optical device 10, by giving periodic electrical signals to the drive unit 13 through a plurality of lead pins 25 and a plurality of wires 26, the movable mirror 11 can be reciprocated along the Z-axis direction at its resonance frequency level. move. In this way, the drive unit 13 functions as an electrostatic actuator.

[Detailed structure of torque bar]

Each of the first torsion bars 145 and each of the second torsion bars 146 has a flat plate shape perpendicular to the X-axis direction. Each first torsion bar 145 is formed to have a length (length in the Y-axis direction) of 30 μm to 300 μm, a width (length in the X-axis direction) of 5 μm to 30 μm, and a thickness (length in the Z-axis direction) of 30 μm to 100 μm, for example. Each second torsion bar 146 is formed, for example, to have a length (length in the Y-axis direction) of 30 μm to 300 μm, a width (length in the X-axis direction) of 5 μm to 30 μm, and a thickness (length in the Z-axis direction) of about 30 μm to 100 μm.

In this embodiment, the length of the first torsion bar 145 is equal to the length of the second torsion bar 146 . The width of the first torsion bar 145 is wider than that of the second torsion bar 146 . The thickness of the first torsion bar 145 is equal to the thickness of the second torsion bar 146 . Furthermore, when at least one of the ends of the first torsion bar 145 on the side of the bracket 116 and the side of the bracket 144 is provided with a widening portion whose width becomes wider as it approaches the end, the so-called first torsion bar The length of 145 refers to the length of the first torsion bar 145 not including the widened part, and the width of the so-called first torsion bar 145 refers to the width of the first torsion bar 145 not including the widened part. . In addition, the width of the first torsion bar 145 refers to the width of the narrowest position (minimum width). These points are also the same for the first torsion bar 155 and the second torsion bars 146 and 156 .

The torsional spring constant of the first torsion bar 145 is greater than that of the second torsion bar 146 . The torsion spring constant of the first torsion bar 145 is, for example, about 0.00004 N‧m/rad. The torsion spring constant of the second torsion bar 146 is, for example, about 0.00003 N‧m/rad. The torsion spring constants of the first torsion bar 145 and the second torsion bar 146 are set within a range of about 0.000001 N‧m/rad to 0.001 N‧m/rad, for example. In this embodiment, the length and thickness of the first torsion bar 145 are equal to the length and thickness of the second torsion bar 146, and the width of the first torsion bar 145 is wider than the width of the second torsion bar 146, whereby the first torsion bar The torsion spring constant of the torsion bar 145 is greater than that of the second torsion bar 146 the torsional spring constant.

Each of the first torsion bars 155 and each of the second torsion bars 156 has a flat plate shape perpendicular to the X-axis direction. The first torsion bar 155 is formed, for example, in the same shape as the first torsion bar 145 . The second torsion bar 156 is formed, for example, in the same shape as the second torsion bar 146 . In this embodiment, the length of the first torsion bar 155 is equal to the length of the second torsion bar 156 . The width of the first torsion bar 155 is wider than that of the second torsion bar 156 . The thickness of the first torsion bar 155 is equal to the thickness of the second torsion bar 156 .

The torsional spring constant of the first torsion bar 155 is greater than that of the second torsion bar 156 . The torsion spring constant of the first torsion bar 155 is, for example, equal to the torsion spring constant of the first torsion bar 145 . The torsion spring constant of the second torsion bar 156 is, for example, equal to the torsion spring constant of the second torsion bar 146 . In this embodiment, the length and thickness of the first torsion bar 155 are equal to the length and thickness of the second torsion bar 156, and the width of the first torsion bar 155 is wider than that of the second torsion bar 156. The torsion spring constant of the torsion bar 155 is larger than the torsion spring constant of the second torsion bar 156 .

[Function and effect]

The function and effect of the optical device 10 will be described while referring to FIG. 5 . Fig. 5 is a graph showing the inclination of the mirror surface 11a during movement in Examples and Comparative Examples. The embodiment corresponds to the optical device 10 of the above-mentioned embodiment. In the embodiment, the width of the first torsion bar 145 is 18 μm, the width of the second torsion bar 146 is 15 μm, the width of the first torsion bar 155 is 18 μm, and the width of the second torsion bar 156 is 16 μm. Each of the first torsion bars 145, 155 and the second torsion bars 146, 156 has a length of 100 μm and a thickness of 70 μm.

In the comparative example, the width of the first torsion bar 145 was 16 μm, the width of the second torsion bar 146 was 17 μm, the width of the first torsion bar 155 was 16 μm, and the width of the second torsion bar 156 was 18 μm. Each of the first torsion bars 145, 155 and the second torsion bars 146, 156 The length is 100 μm, and the thickness is 70 μm. The other configurations of the comparative example are the same as those of the example.

In the embodiment, in the configuration where the width of the first torsion bars 145, 155 is 18 μm and the width of the second torsion bars 146, 156 is 16 μm, this corresponds to a case where the width of the second torsion bar 146 is narrowed by 1 μm. In the comparative example, when the width of the first torsion bars 145 and 155 is 16 μm and the width of the second torsion bars 146 and 156 is 18 μm, it corresponds to the case where the width of the second torsion bar 146 is narrowed by 1 μm.

In the configuration before the width of the second torsion bar 146 is narrowed in the embodiment, the torsion spring constant of the first torsion bar 145 is greater than that of the second torsion bar 146, and the torsion spring constant of the first torsion bar 155 is greater than that of the first torsion bar 155. 2 The torsion spring constant of the torsion bar 156. In the configuration before the width of the second torsion bar 146 is narrowed in the comparative example, the torsion spring constant of the first torsion bar 145 is smaller than that of the second torsion bar 146, and the torsion spring constant of the first torsion bar 155 is smaller than that of the first torsion bar 155. 2 The torsion spring constant of the torsion bar 156.

The variation in the shape of the second torsion bar 146 as described above occurs for the following reasons. The optical device 10 is formed on the SOI substrate 50 using MEMS technology (patterning and etching) or the like. In the second torsion bar 146, processing in the longitudinal direction is performed by patterning, and processing in the width direction is performed by etching. Therefore, there are cases where the length of the second torsion bar 146 is less likely to vary, while the width of the second torsion bar 146 may vary due to manufacturing errors or the like. Furthermore, since the processing in the thickness direction of the second torsion bar 146 is performed by etching using the intermediate layer 53 as an etching stopper layer, the thickness of the second torsion bar 146 is less likely to vary.

As shown in FIG. 5 , when the width of the second torsion bar 146 is narrowed as in the embodiment and the comparative example, the mirror surface 11 a (movable mirror 11 ) tilts from the target posture when the movable mirror 11 moves in the Z-axis direction. In the examples and comparative examples, the target posture is a posture in which the mirror surface 11a is perpendicular to the Z-axis direction Potential.

As shown in FIG. 5 , in the embodiment, the inclination of the mirror surface 11 a from the target posture is smaller than in the comparative example. Thus, by making the torsional spring constants of the first torsion bars 145, 155 larger than the torsion spring constants of the second torsion bars 146, 156, respectively, the inclination of the mirror surface 11a from the target posture can be suppressed. This situation is also clear in the embodiment according to the following situation: Even if the rate of change of the width of the second torsion bar 146 (the ratio of the deformation amount relative to the original length) is greater than the rate of change in the comparative example, compared with the comparative example , the inclination of the mirror surface 11a from the target posture is also small.

As explained above, in the optical device 10, the torsion spring constant of the first torsion bar 145 connected between the rod 141 and the movable mirror 11 is larger than that of the second torsion bar 146 connected between the rod 141 and the base 12. Torsional spring constant. Thereby, even when the shape of at least one of the first torsion bar 145 and the second torsion bar 146 deviates due to manufacturing errors, etc., the movable mirror 11 can be suppressed from moving in the Z-axis direction. The target pose is tilted. Also, the torsion spring constant of the first torsion bar 155 connected between the rod 151 and the movable mirror 11 is greater than the torsion spring constant of the second torsion bar 156 connected between the rod 151 and the base 12 . Thereby, even when the shape of at least one of the first torsion bar 155 and the second torsion bar 156 deviates due to manufacturing errors, etc., the movable mirror 11 can be suppressed from moving in the Z-axis direction. The target pose is tilted. Thus, according to the optical device 10, it is possible to suppress a decrease in optical characteristics caused by variations in the shapes of the first torsion bars 145, 155 and the second torsion bars 146, 156. Furthermore, in the optical device 10, not only when the width of the second torsion bar 146 is narrowed, but also when the width of the second torsion bar 146 is widened, the tilting of the movable mirror 11 from the target posture can be suppressed. Also, when at least one of the length and thickness of the second torsion bar 146 deviates, the movable mirror 11 can be suppressed from tilting from the target posture. Similarly, not only when the shape of the second torsion bar 146 deviates, but also when at least one of the shapes of the first torsion bars 145, 155 and the second torsion bar 156 deviates , the tilting of the movable mirror 11 from the target posture can also be suppressed.

In addition, in the optical device 10, when viewed from the Z-axis direction, the width of the first torsion bars 145, 155 is wider than the width of the second torsion bars 146, 156. Thereby, the torsion spring constant of the first torsion bar 145, 155 can be preferably larger than the torsion spring constant of the second torsion bar 146, 156.

In addition, in the optical device 10 , the base 12 , the movable mirror 11 , the first elastic support portion 14 , and the second elastic support portion 15 are constituted by the SOI substrate 50 . Thereby, in the optical device 10 formed by the MEMS technology, it is possible to suppress the reduction of the optical characteristics caused by the uneven shape of the first torsion bars 145, 155 and the second torsion bars 146, 156.

Moreover, the optical device 10 is provided with: fixed comb-teeth electrodes 161, 163, which are arranged on the base 12, and have a plurality of fixed comb-teeth 161a, 163a; and movable comb-teeth electrodes 162, 164, which are arranged on the first elastic The supporting part 14 and the second elastic supporting part 15 have a plurality of movable comb teeth 162a, 164a arranged alternately with a plurality of fixed comb teeth 161a, 163a. Thereby, the actuator part 16 used for moving the movable mirror 11 can be simplified and power consumption can be reduced.

In addition, the optical device 10 includes a first elastic support portion 14 and a second elastic support portion 15 . This makes it possible to stabilize the movement of the movable mirror 11 compared to, for example, a case where only one elastic support portion is provided. Also, for example, the total number of torsion bars can be reduced compared to the case of having three or more elastic support portions. As a result, the spring constant of each torsion bar can be ensured, and it is less likely to be affected by the uneven shape of the torsion bar.

As mentioned above, although one embodiment of this invention was described, this invention is not limited to the said embodiment. The material and shape of each component are not limited to those mentioned above, and various materials and shapes can be used.

In the above-mentioned embodiment, it is also possible by making the width of the first torsion bar 145 and the width of the first torsion bar 145 The widths of the 2 torsion bars 146 are equal, and the length of the first torsion bar 145 is shorter than that of the second torsion bar 146, so that the torsional spring constant of the first torsion bar 145 is greater than that of the second torsion bar 146. Similarly, the width of the first torsion bar 155 is equal to the width of the second torsion bar 156, and the length of the first torsion bar 155 is shorter than the length of the second torsion bar 156, so that the first torsion bar 155 The torsional spring constant is greater than that of the second torsion bar 156.

Even in this case, similarly to the above-mentioned embodiment, it is possible to suppress a reduction in optical characteristics due to variations in shape of the first torsion bars 145 and 155 and the second torsion bars 146 and 156 . That is, as long as the torsional spring constant of the first torsion bar 145 is greater than that of the second torsion bar 146, the relationship between the length, width and thickness of the first torsion bar 145 and the second torsion bar 146 can be arbitrary. to choose. This point is also the same for the first torsion bar 155 and the second torsion bar 156 .

In the above embodiment, when viewed from the Z-axis direction, each of the main body portion 111 and the mirror surface 11a may have an arbitrary shape such as a rectangular shape or an octagonal shape. When viewed from the Z-axis direction, the frame portion 112 may be in any ring shape such as a rectangular ring, an octagonal ring, or the like. The frame portion 112 and the connection portion 113 may also be omitted. Each of the 1st beam part 115b, the 2nd beam part 112b, and the 3rd beam part 113b can be formed in arbitrary shapes, and can also be omitted. In the above-mentioned embodiment, the first torsion support part is constituted by the plate-shaped first torsion bar 145, but the configuration of the first torsion support part is not limited to this. The first torsion bar 145 may be in any shape such as a rod. The first torsion support portion may be configured by connecting a plurality of (for example, two) torsion bars in series via a connection portion. These points are also the same for the first torsion bar 155 and the second torsion bars 146 and 156 (second torsion supporting parts). For example, the second torsion support portion may be configured by connecting a plurality of (for example, three) torsion bars in series via a connection portion.

In the above-mentioned embodiment, the connecting rods 143 and 153 may also be omitted. in this case In this case, each of the first optical function part 17 and the second optical function part 18 may be constituted by openings formed in the SOI substrate 50 . Each of the 1st optical function part 17 and the 2nd optical function part 18 may have arbitrary cross-sectional shapes, such as a circular shape and an octagonal shape. The movable comb electrodes 162 and 164 may also be provided on the movable mirror 11 , for example, may also be arranged along the outer edge of the frame portion 112 . Instead of the movable mirror 11, the optical device 10 may include a movable part provided with an optical function part other than the mirror surface 11a. As another optical function part, a lens etc. are mentioned, for example. The actuator part 16 is not limited to an electrostatic actuator, For example, a piezoelectric actuator, an electromagnetic actuator, etc. may be sufficient. The optical module 1 is not limited to those that constitute FTIR, and may also constitute other optical systems. The optical device 10 may also be constituted by other than the SOI substrate 50, for example, may be constituted by a substrate composed only of silicon.

10‧‧‧optical device

11‧‧‧Movable mirror (movable part)

11a‧‧‧Mirror (Optical Function Department)

12‧‧‧base

12b‧‧‧main face

12c‧‧‧opening

13‧‧‧Drive Department

14‧‧‧The first elastic support department

15‧‧‧The second elastic support department

16‧‧‧Actuator Department

17‧‧‧The first optical function department

18‧‧‧The second optical function department

50‧‧‧SOI substrate

51‧‧‧Support layer

111‧‧‧Body Department

112‧‧‧Frame

113‧‧‧connection part

116‧‧‧Bracket

117‧‧‧Bracket

121‧‧‧Electrode pad

122‧‧‧Electrode pad

141‧‧‧bar

141a‧‧‧end

141b‧‧‧end

141c‧‧‧protrusion

142‧‧‧connecting rod

143‧‧‧connecting rod

144‧‧‧Stent

145‧‧‧1st torsion bar (1st torsion support part)

146‧‧‧The second torsion bar (the second torsion support part)

147‧‧‧electrode support part

151‧‧‧bar

151a‧‧‧end

151b‧‧‧end

151c‧‧‧protrusion

152‧‧‧connecting rod

153‧‧‧connecting rod

154‧‧‧Stent

155‧‧‧1st torsion bar (1st torsion support part)

156‧‧‧The second torsion bar (the second torsion support part)

157‧‧‧electrode support part

161‧‧‧Fixed comb electrodes

161a‧‧‧Fixed comb

162‧‧‧Movable comb electrode

162a‧‧‧movable comb

163‧‧‧Fixed comb electrodes

163a‧‧‧Fixed comb

164‧‧‧Movable comb electrode

164a‧‧‧movable comb

R1‧‧‧axis

R2‧‧‧axis

Claims (11)

An optical device comprising: a base having a main surface; a movable part having an optical function part; The above-mentioned movable part is supported by moving in a first direction perpendicular to the above-mentioned main surface; and the above-mentioned elastic support part has: a rod; a first torsion support part, which extends along a second direction perpendicular to the above-mentioned first direction, and is connected to between the rod and the movable part; and a second torsion support part extending along the second direction and connected between the rod and the base; the torsion spring constant of the first torsion support part is larger than that of the first torsion support part 2. The torsion spring constant of the torsion support portion, wherein the rod extends in a direction intersecting the first direction and the second direction. The optical device according to claim 1, wherein when viewed from the first direction, the width of the first twist supporting portion is wider than the width of the second twist supporting portion. The optical device according to claim 1, wherein when viewed from the first direction, the length of the first twist supporting portion is shorter than the length of the second twist supporting portion. The optical device according to claim 2, wherein when viewed from the first direction, the length of the first twist supporting portion is shorter than the length of the second twist supporting portion. The optical device according to any one of claims 1 to 4, wherein the above-mentioned base, the above-mentioned movable part and the above-mentioned elastic supporting part are composed of a silicon-on-insulator (Silicon On Insulator, SOI) substrate. The optical device according to any one of Claims 1 to 4, further comprising: a fixed comb electrode provided on the base, and having a plurality of fixed combs; and a movable comb electrode provided on the movable part and at least one of the elastic supporting parts, and has a plurality of movable comb teeth arranged alternately with the plurality of fixed comb teeth. The optical device according to claim 5, further comprising: a fixed comb electrode disposed on the base, and having a plurality of fixed combs; and a movable comb electrode disposed between the movable part and the elastic support part At least one, and has a plurality of movable comb teeth arranged alternately with the plurality of fixed comb teeth. The optical device according to any one of claims 1 to 4, which only has a pair of the above-mentioned elastic supporting parts. According to the optical device of claim 5, it only has a pair of the above-mentioned elastic supporting parts. According to the optical device of claim 6, it only has a pair of the above-mentioned elastic supporting parts. According to the optical device of claim 7, it only has a pair of the above-mentioned elastic supporting parts.

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