TW201906783A - Optical device - Google Patents

Abstract

An optical device that comprises: a base that has a main surface; a mobile part that has an optical function part; and an elastic support part that is connected between the base and the mobile part and supports the mobile part such that the mobile part can move along a first direction that is orthogonal to the main surface. The elastic support part has: a lever; a first torsional support part that extends along a second direction and is connected between the lever and the mobile part, the second direction being the orthogonal to the first direction; and a second torsional support part that extends along the second direction and is connected between the lever and the base. The torsional spring constant of the first torsional support part is greater than the torsional spring constant of the second torsional support part.

Description

Optical device

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

As a MEMS device, there is known an optical device including: a base; a movable part having an optical function part; and an elastic support part connected between the base and the movable part and moving along the moving direction with the movable part The movable part is supported to be movable (for example, refer to Patent Document 1). In such an optical device, there is a case where the elastic supporting portion includes a torsion supporting portion that is torsionally deformed when the movable portion moves in the moving direction. Advanced technical literature Patent literature

Patent Literature 1: US Patent Application Publication No. 2008/0284078

[Problems to be solved by the invention]

In the optical device as described above, the following configuration is considered: In order to allow the movable portion to move largely along the moving direction, reducing the width of the torsion support portion makes the torsion support portion easy to twist. However, in such a configuration, when the shape of the torsion support part is deviated due to manufacturing errors or the like, the movable part is inclined from the target posture when the movable part moves in the moving direction, and as a result, the optical characteristics may be degraded.

An object of the present invention is to provide an optical device capable of suppressing the decrease in optical characteristics caused by the unevenness of the shape of the torsion support. [Technical means to solve the problem]

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

In this optical device, the torsion spring constant of the first torsion support portion connected between the rod and the movable portion is greater than the torsion spring constant of the second torsion support portion 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 is deviated due to manufacturing errors, etc., the movable portion can be suppressed from the target posture when the movable portion moves in the first direction tilt. Thus, according to this optical device, it is possible to suppress a decrease in optical characteristics caused by the unevenness of the shape of the torsion 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 torsional support portion may be wider than the width of the second torsional support portion. In this case, the torsion spring constant of the first torsion support portion can be preferably greater than the torsion spring constant of the second torsion support portion.

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

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

An optical device according to an aspect of the present invention may further include: a fixed comb-teeth electrode, which is provided on the base, and has a plurality of fixed comb teeth; and a movable comb-teeth electrode, which is provided on the movable portion and the elastic support portion At least one of them has a plurality of movable comb teeth alternately arranged with the plurality of fixed comb teeth. In this case, the actuator part that can be used to move the movable part can be simplified and the power consumption can be reduced.

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

According to one aspect of the present invention, it is possible to provide an optical device that can suppress the decrease in optical characteristics caused by the unevenness of the shape of the torsion support portion.

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 symbols are used for the same or corresponding elements, and repeated explanations are 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 portion) 11. In the optical module 1, the beam splitter unit 3 constitutes an interference optical system for the measurement light L0 by the movable mirror 11 and the fixed mirror 21. The interference optical system here is Michelson interference 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 portion) 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 in the Z-axis direction (the direction parallel to the Z-axis, the first direction) perpendicular to the main surface 12a. The drive unit 13 moves the movable mirror 11 along the Z-axis direction. The first optical function portion 17 is arranged on one side of the movable mirror 11 in the X-axis direction (the direction parallel to the X-axis and the third direction) perpendicular to the Z-axis direction when viewed from the Z-axis direction. The second optical function portion 18 is arranged on the other side of the movable mirror 11 in the X-axis direction when viewed from the Z-axis direction. Each of the first optical function section 17 and the second optical function section 18 is provided in the light passing opening of the base 12 and opens on one side and the other side in the Z-axis direction. In addition, in the optical module 1, the second optical function portion 18 is not used as a light passage opening. When the optical device 10 is applied to other devices, at least one of the first optical functional part 17 and the second optical functional part 18 can be used as the optical functional part, or the first optical functional part 17 and the first 2 Both of the optical function sections 18 are not used as optical function sections.

The fixed mirror 21 has a mirror surface 21a extending along a plane parallel to the main surface 12a (a plane perpendicular to the Z-axis direction). 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).

In addition to the optical device 10 and the fixed mirror 21, the mirror unit 2 has a support 22, a submount substrate 23, and a package 24. The package 24 houses the optical device 10, the fixed mirror 21, the support 22, and the sub-mount substrate 23. The package 24 includes a bottom wall 241, a side wall 242, and a top wall 243. The package 24 is formed in a rectangular parallelepiped box shape, for example. The package 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 faces the bottom wall 241 in the Z-axis direction, and is fixed to the side wall 242. The top wall 243 has translucency with respect to the measurement light L0. In the mirror unit 2, a space S is formed by the package 24. The space S is opened outside the mirror unit 2 through, for example, a vent hole or a gap provided in the package 24. In the case where such a space S is not an air-tight space, it is possible to suppress the contamination or staining of the mirror surface 11a caused by outgassing from the resin material existing in the package 24 or moisture existing in the package 24. Furthermore, the space S may also be a gas-tight space maintained with a high degree of vacuum, or a gas-tight space filled with an inert gas such as nitrogen.

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

The submount substrate 23 has an opening 23a. The fixed mirror 21 is arranged on the surface 22c on the side of the submount substrate 23 in the support 22 so as to be located in the opening 23a. That is, the fixed mirror 21 is arranged on the surface 22c of the support 22 on the side 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 portion 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 to the bottom wall 241 while penetrating the bottom wall 241. Each lead pin 25 is electrically connected to the drive unit 13 via a wire 26. In the mirror unit 2, the electrical signal for moving the movable mirror 11 in the Z-axis direction is given to the driving unit 13 through the plurality of lead pins 25 and the plurality of wires 26.

The beam splitter unit 3 is supported by the top wall 243 of the package body 24. Specifically, the beam splitter unit 3 is fixed to the surface 243a 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 dichroic mirror unit 3 has a half mirror surface 31, a total reflection mirror surface 32, and a plurality of optical surfaces 33a, 33b, 33c, and 33d. The beam splitter unit 3 is configured by joining a plurality of optical blocks. The half mirror 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 when viewed from the Z-axis direction, overlaps the first optical function portion 17 of the optical device 10 and the mirror surface 21a of the fixed mirror 21. 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 by 45 degrees with respect to the optical surface 33a, and when viewed from the Z-axis direction, overlaps the first optical function portion 17 of the optical device 10 and the mirror surface 21a of the fixed mirror 21. The half mirror surface 31 reflects a part of the measurement light L0 incident on the optical surface 33a along the Z-axis direction along the X-axis direction, and transmits the remaining part of the measurement light L0 along the Z-axis direction through the fixed mirror 21 side.

The total reflection mirror surface 32 is a surface parallel to the half reflection mirror surface 31, and overlaps with the mirror surface 11a of the movable mirror 11 when viewed from the Z axis direction and overlaps with 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 movable mirror 11 side along the Z-axis direction.

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

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

The optical surface 33d is, for example, a surface perpendicular to the X-axis direction, and overlaps the semi-reflective 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 reflected by the mirror surface 11a of the movable mirror 11 and the total reflection mirror surface 32 in sequence and then transmitted through the semi-reflective mirror surface 31, and the measurement light L0 reflected by the mirror surface 21a of the fixed mirror 21 and the semi-reflection mirror surface 31 in this order The remaining part of the interference light.

In the optical module 1 configured as above, if the measurement light L0 enters the beam splitter 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 half-reflective mirror surface 31 and total reflection After being reflected in order, the mirror surface 32 advances toward the mirror surface 11a of the movable mirror 11. Then, after a part of the measurement light L0 is reflected by the mirror surface 11a of the movable mirror 11, it travels in the opposite direction on the same optical path (the optical path P1 described below) and passes through the semi-reflective mirror surface 31 of the dichroic mirror unit 3.

On the other hand, after the remaining portion of the measurement light L0 passes through the semi-reflective mirror surface 31 of the beam splitter unit 3, it passes through the first optical function unit 17, further passes through the support 22, and proceeds toward the mirror surface 21 a of the fixed mirror 21. Then, the remaining part of the measurement light L0 is reflected by the mirror surface 21a of the fixed mirror 21, and then proceeds in the opposite direction on the same optical path (optical path P2 described below) and is reflected by the semi-reflective mirror surface 31 of the dichroic mirror unit 3.

A part of the measurement light L0 transmitted through the half mirror surface 31 of the beam splitter unit 3 and the remaining portion of the measurement light L0 reflected by the half mirror surface 31 of the beam splitter unit 3 become interference light, that is, measurement light L1. The unit 3 exits the optical module 1 via the optical surface 33d. According to the optical module 1, since the movable mirror 11 can be moved back and forth at high speed along the Z-axis direction, a small and high-precision FTIR (Fourier Transform infrared spectroscopy) can be provided.

The support 22 corrects the optical path difference between the optical path P1 between the dichroic mirror unit 3 and the movable mirror 11 and the optical path P2 between the dichroic mirror unit 3 and the fixed mirror 21. Specifically, the optical path P1 is an optical path that reaches the mirror surface 11a of the movable mirror 11 at the reference position from the semi-reflective mirror surface 31 through the total reflection mirror surface 32 and the optical surface 33b in this order, and is a portion of the measurement light L0 that advances. The optical path P2 is an optical path that reaches the mirror surface 21a of the fixed mirror 21 from the semi-reflective mirror surface 31 through the optical surface 33c and the first optical function portion 17 in order, and is an optical path that advances the remaining portion of the measurement light L0. The support 22 is based on the optical path length of the optical path P1 (considering the optical path length of each medium through which the optical path P1 passes) and the optical path length of the optical path P2 (considering the optical path length of each medium through which the optical path P2 passes) 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 22 can be formed of the same translucent material as the optical blocks constituting the beam splitter unit 3, for example. In this case, the thickness of the support 22 (length in the Z-axis direction) may be the same as the distance between the semi-reflective mirror surface 31 and the total-reflective mirror surface 32 in the X-axis direction. [Composition of Optical Device]

As shown in FIGS. 2, 3 and 4, the portion of the movable mirror 11 other than the mirror surface 11 a, the base 12, the driving unit 13, the first optical function unit 17 and the second optical function unit 18 are provided by SOI Insulator) substrate 50. That is, the optical device 10 is configured by the SOI substrate 50. The optical device 10 is formed in a rectangular plate shape, for example. 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 support 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 support layer 51 and the device layer 52.

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

The movable mirror 11 is arranged with the intersection of the axis R1 and the axis R2 as the 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 symmetrical about the axis R1 and line symmetrical about the axis R2.

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

The first beam portion 115b is formed by a part of the support 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 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 115b extends along the outer edge of the body portion 111. In the present embodiment, when viewed from the Z-axis direction, the outer edge of the first beam portion 115b is spaced apart from the outer edge of the main body portion 111 by a specific interval and extends along 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 is spaced apart from the outer edge of the mirror surface 11a by a specific interval, and extends along the outer edge of the mirror surface 11a.

When viewed from the Z-axis direction, the frame portion 112 is spaced apart from the body portion 111 by a specific interval to surround the body portion 111. When viewed from the Z-axis direction, the frame portion 112 has an annular shape. The frame portion 112 has a second body portion 112a and a second beam portion 112b. The second body portion 112a is formed by a part of the device layer 52.

The second beam portion 112b is formed by a part of the support 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 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 central 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 is spaced apart from the outer edge of the frame portion 112 by a certain interval, and extends along the outer edge of the frame portion 112. When viewed from the Z-axis direction, the inner edge of the second beam portion 112b is spaced apart from the inner edge of the frame portion 112 by a specific interval, and extends along the inner edge of the frame portion 112.

The thickness of the second beam portion 112b in the Z-axis direction is equal to the thickness of the first beam portion 115b in the Z-axis direction. 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. The length of the first beam portion 115b in the radial direction of the one beam portion 115b. In this respect, the width of the second beam portion 112b when viewed from the Z-axis direction is also the same.

Each of the pair of connecting portions 113 connects the body portion 111 and the frame portion 112 to each other. The pair of connecting portions 113 are respectively disposed on one side and the other side in the Y-axis direction with respect to the body portion 111. Each connecting portion 113 has a third body portion 113a and a third beam portion 113b. The third body portion 113a is formed by a part of the device layer 52. The third body portion 113a is connected to the first body portion 115a and the second body portion 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 of the third body portion 113a on the main surface 12b side. The third beam portion 113b is formed such that the thickness of the connecting 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 third beam portion 113b is larger than the width of each of the first beam portion 115b and the second beam portion 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 bracket 116 and each bracket 117 are formed by a part of the device layer 52. Each bracket 116 extends along the Y-axis direction and has a rectangular shape when viewed from the Z-axis direction. One bracket 116 protrudes from the side surface of the frame portion 112 toward one side in the Y-axis direction, and the other bracket 116 protrudes from the side surface of the frame portion 112 toward the other side in the Y-axis direction. The pair of brackets 116 are arranged on the same center line parallel to the Y-axis direction. Each holder 116 extends from the end of the frame portion 112 on the side of the first optical function portion 17.

Each bracket 117 extends along the Y-axis direction and has a rectangular shape when viewed from the Z-axis direction. One bracket 117 protrudes from the side surface of the frame portion 112 toward one side in the Y-axis direction, and the other bracket 117 protrudes from the side surface 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 the end of the frame portion 112 on the side of the second optical functional portion 18 (the side opposite to the first optical functional portion 17).

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

Each of the first elastic support portion 14 and the second elastic support portion 15 is connected between the base 12 and the movable mirror 11. The first elastic support portion 14 and the second elastic support portion 15 support the movable mirror 11 so as to be movable in the Z-axis direction.

The first elastic support portion 14 has a pair of rods 141, a link 142, a link 143, a pair of brackets 144, a pair of first torsion bars (first torsion support portion) 145, and a pair of second torsion bars (second torsion Supporting part) 146, and a pair of electrode supporting parts 147. The pair of rods 141 are arranged on both sides of the first optical function portion 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 installed between the end 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 installed between the end 141b of the pair of rods 141 opposite to the movable mirror 11. The link 143 has a plate shape extending along a plane perpendicular to the Z-axis direction and extending along the Y-axis direction. In this embodiment, the first optical function portion 17 is an opening defined by a pair of rods 141, links 142, and links 143. When viewed from the Z-axis direction, the first optical function portion 17 has a rectangular shape. The first optical function unit 17 is, for example, a cavity. Alternatively, a material having translucency with respect to the measurement light L0 may be arranged in the opening constituting the first optical function portion 17.

Each bracket 144 has a rectangular shape when viewed from the Z-axis direction. Each bracket 144 is provided on the surface of the movable mirror 11 side of the link 142 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 installed 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 in 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 bars 146 are respectively erected between the end 141b on the opposite side of the movable mirror 11 in one rod 141 and the base 12, and the end 141b on the opposite side of the movable mirror 11 in the other rod 141 and 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 in the Y-axis direction. The pair of second torsion bars 146 are arranged on the same center line parallel to the Y-axis direction. An end portion 141b of each lever 141 is provided with a protruding portion 141c protruding outward in the Y-axis direction, and the second torsion bar 146 is connected to the protruding portion 141c.

Each electrode support portion 147 extends along the Y-axis direction and has a rectangular shape when viewed from the Z-axis direction. One electrode support portion 147 extends from the middle portion of one rod 141 toward the side opposite to the first optical function portion 17. The other electrode support portion 147 protrudes from the middle portion of the other rod 141 to the side opposite to the first optical function portion 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 second elastic support portion 15 includes a pair of rods 151, a link 152, a link 153, a pair of brackets 154, a pair of first torsion bars (first torsion support portions) 155, and a pair of second torsion bars (second torsion bars) Supporting part) 156, and a pair of electrode supporting parts 157. The pair of rods 151 are arranged on both sides of the second optical function portion 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 spans between the end 151a of the pair of rods 151 on the movable mirror 11 side. The link 152 has a plate shape extending along a plane perpendicular to the Z-axis direction. The link 152 extends in the Y-axis direction. The link 153 is installed between the end portions 151b of the pair of rods 151 on the side opposite to the movable mirror 11. The link 153 has a plate shape extending along a plane perpendicular to the Z-axis direction and extending along the Y-axis direction. In this embodiment, the second optical function portion 18 is an opening defined by a pair of rods 151, links 152, and links 153. When viewed from the Z-axis direction, the second optical function portion 18 has a rectangular shape. The second optical function unit 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 has a rectangular shape when viewed from the Z-axis direction. Each bracket 154 is provided on the surface of the movable mirror 11 side of the link 152 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.

The pair of first torsion bars 155 are respectively installed 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 in 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 second torsion bars 156 are erected between the end 151b of the opposite side of the movable mirror 11 in one rod 151 and the base 12, and the end 151b of the opposite side of the movable mirror 11 in the other rod 151 and Between 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 in the Y-axis direction. The pair of second torsion bars 156 are arranged on the same center line parallel to the Y-axis direction. An end portion 151b of each lever 151 is provided with a protrusion portion 151c protruding outward in the Y-axis direction, and the second torsion bar 156 is connected to the protrusion portion 151c.

Each electrode support portion 157 extends along the Y-axis direction and has a rectangular shape when viewed from the Z-axis direction. One electrode support portion 157 extends from the middle portion of one rod 151 toward the side opposite to the second optical function portion 18. The other electrode support portion 157 protrudes from the middle portion of the other rod 151 to the side opposite to the second optical function portion 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 portion 16 moves the movable mirror 11 in the Z-axis direction. The actuator portion 16 has a pair of fixed comb-teeth electrodes 161, a pair of movable comb-teeth electrodes 162, a pair of fixed comb-teeth electrodes 163, and a pair of movable comb-teeth electrodes 164. The positions of the fixed comb-shaped electrodes 161 and 163 are fixed. The movable comb-teeth electrodes 162 and 164 move with the movement of the movable mirror 11.

A fixed comb-shaped electrode 161 is provided on the surface of the device layer 52 of the base 12 opposite to the electrode support portion 147. The other fixed comb-shaped electrode 161 is provided on the surface of the device layer 52 opposite to the other electrode support portion 147. Each fixed comb-shaped electrode 161 has a plurality of fixed comb-shaped teeth 161a extending along a plane perpendicular to the Y-axis direction. The fixed comb teeth 161a are arranged at predetermined intervals in the Y-axis direction.

A movable comb-shaped electrode 162 is provided on the surfaces of both sides of the electrode support portion 147 in the X-axis direction. The other movable comb-teeth electrode 162 is provided on the surface of the other electrode support portion 147 on both sides in the X-axis direction. Each movable comb-teeth electrode 162 has a plurality of movable comb-teeth 162a extending along a plane perpendicular to the Y-axis direction. The movable comb teeth 162a are arranged at predetermined intervals in the Y-axis direction.

In one fixed comb tooth electrode 161 and one movable comb tooth electrode 162, a plurality of fixed comb teeth 161a and a plurality of movable comb teeth 162a are alternately arranged. That is, each fixed comb tooth 161a of one fixed comb electrode 161 is located between the movable comb teeth 162a of one movable comb 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 alternately arranged. That is, each fixed comb tooth 161a of the other fixed comb-teeth electrode 161 is located between the movable comb teeth 162a of the other movable comb-teeth electrode 162. In the pair of fixed comb-teeth electrodes 161 and the pair of movable comb-teeth electrodes 162, adjacent fixed comb teeth 161a and movable comb teeth 162a are opposed 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-shaped electrode 163 is provided on the surface of the device layer 52 of the base 12 opposite to the electrode support portion 157. The other fixed comb electrode 163 is provided on the surface of the device layer 52 opposite to the other electrode support portion 157. Each fixed comb electrode 163 has a plurality of fixed comb teeth 163a extending along a plane perpendicular to the Y-axis direction. The fixed comb teeth 163a are arranged at predetermined intervals in the Y-axis direction.

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

In one fixed comb tooth electrode 163 and one movable comb tooth electrode 164, a plurality of fixed comb teeth 163a and a plurality of movable comb teeth 164a are alternately arranged. That is, each fixed comb tooth 163a of one fixed comb electrode 163 is located between the movable comb teeth 164a of one movable comb 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 alternately arranged. That is, each fixed comb tooth 163a of the other fixed comb-teeth electrode 163 is located between the movable comb teeth 164a of the other movable comb-teeth electrode 164. In the pair of fixed comb-teeth electrodes 163 and the pair of movable comb-teeth electrodes 164, adjacent fixed comb teeth 163a and movable comb teeth 164a are opposed 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.

The base 12 is provided with a plurality of electrode pads 121 and 122. The electrode pads 121 and 122 are formed on the surface of the device layer 52 in the opening 12c formed on the main surface 12b of the base 12 so as to reach the device layer 52. Each electrode pad 121 is electrically connected to the fixed comb electrode 161 or the fixed comb electrode 163 via the device layer 52. Each electrode pad 122 is electrically connected to the movable comb-teeth electrode 162 or the movable comb-teeth electrode 164 via the first elastic support portion 14 or the second elastic support portion 15. The lead 26 is laid between the electrode pads 121 and 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 in which the movable mirror 11 moves on the upper side is generated between the fixed comb electrode 161 and the movable comb electrode 162 facing each other, and between the fixed comb electrode 163 and the movable comb electrode 164 facing each other Electrostatic force. At this time, the first torsion bars 145 and 155 and the second torsion bars 146 and 156 of the first elastic support portion 14 and the second elastic support portion 15 twist, and the first elastic support portion 14 and the second elastic support portion 15 produces elastic force. In the optical device 10, by providing a periodic electrical signal to the driving unit 13 through the plurality of lead pins 25 and the plurality of wires 26, the movable mirror 11 can be reciprocated at its resonance frequency level along the Z-axis direction mobile. In this way, the drive unit 13 functions as an electrostatic actuator. [Detailed composition of torsion bar]

Each first torsion bar 145 and each second torsion bar 146 have a flat plate shape perpendicular to the X-axis direction. Each first torsion bar 145 is formed, for example, with 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 ~ 100 μm. Each second torsion bar 146 is formed, for example, with 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 ~ 100 μm.

In this embodiment, the length of the first torsion bar 145 and the length of the second torsion bar 146 are equal. The width of the first torsion bar 145 is wider than the width 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 an end portion of at least one of the bracket 116 side and the bracket 144 side of the first torsion bar 145 is provided with a widened portion that is wider as the end portion is wider, the so-called first torsion bar The length of 145 refers to the length of the first torsion bar 145 that does not include the widened portion. The width of the first torsion bar 145 refers to the width of the first torsion bar 145 that does not include the widened portion . In addition, the width of the first torsion bar 145 refers to the width (minimum width) at the position where the width is the narrowest. These aspects are also the same for the first torsion bar 155 and the second torsion bar 146 and 156.

The torsion spring constant of the first torsion bar 145 is greater than the torsion spring constant 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 in the 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 The torsion spring constant of the torsion bar 145 is greater than the torsion spring constant of the second torsion bar 146.

Each first torsion bar 155 and each second torsion bar 156 have a flat plate shape perpendicular to the X-axis direction. The first torsion bar 155 is formed in the same shape as the first torsion bar 145, for example. The second torsion bar 156 is formed in the same shape as the second torsion bar 146, for example. In this embodiment, the length of the first torsion bar 155 and the length of the second torsion bar 156 are equal. The width of the first torsion bar 155 is wider than the width 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 torsion spring constant of the first torsion bar 155 is greater than the torsion spring constant of the second torsion bar 156. The torsion spring constant of the first torsion bar 155 is equal to the torsion spring constant of the first torsion bar 145, for example. The torsion spring constant of the second torsion bar 156 is equal to the torsion spring constant of the second torsion bar 146, for example. 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 the width of the second torsion bar 156, whereby the first The torsion spring constant of the torsion bar 155 is greater than the torsion spring constant of the second torsion bar 156. [Function and effect]

Referring to FIG. 5, the function and effect of the optical device 10 will be described. 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 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. The length of each of the first torsion bars 145 and 155 and the second torsion bars 146 and 156 is 100 μm, and the thickness is 70 μm.

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

In the embodiment, in a configuration in which the width of the first torsion bars 145 and 155 is 18 μm and the width of the second torsion bars 146 and 156 is 16 μm, this corresponds to the case where the width of the second torsion bar 146 is narrowed by 1 μm . In the comparative example, in the case where 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, this 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 the torsion spring constant of the second torsion bar 146, and the torsion spring constant of the first torsion bar 155 is greater than the 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 less than the torsion spring constant of the second torsion bar 146, and the torsion spring constant of the first torsion bar 155 is less than the 2 The torsion spring constant of the torsion bar 156.

The deviation of the shape of the second torsion bar 146 as described above occurs due to 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, the processing in the longitudinal direction is performed by patterning, and the processing in the width direction is performed by etching. Therefore, there is a case where the length of the second torsion bar 146 is unlikely to vary, and on the other hand, the width of the second torsion bar 146 varies due to manufacturing errors or the like. In addition, since the thickness direction of the second torsion bar 146 is processed by etching using the intermediate layer 53 as an etching stop layer, the thickness of the second torsion bar 146 is less likely to vary.

As shown in FIG. 5, in the case where the width of the second torsion bar 146 is narrow 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.

As shown in FIG. 5, in the embodiment, the tilt of the mirror surface 11 a from the target posture is smaller than that of the comparative example. In this way, by making the torsion spring constants of the first torsion bars 145 and 155 larger than the torsion spring constants of the second torsion bars 146 and 156, respectively, the tilt of the mirror surface 11a from the target posture can be suppressed. This situation is also clarified in the examples based on the following: even if the rate of change of the width of the second torsion bar 146 (the ratio of the amount of deformation relative to the original length) is greater than the rate of change in the comparative example, compared with the comparative example The tilt of the mirror surface 11a from the target posture is also small.

As described 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 greater than that of the second torsion bar 146 connected between the rod 141 and the base 12 Torsion spring constant. With this, even when the shape of at least one of the first torsion bar 145 and the second torsion bar 146 is deviated due to manufacturing errors or the like, the movable mirror 11 can be suppressed from moving when the movable mirror 11 moves in the Z-axis direction The target posture is tilted. Moreover, 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 is deviated due to manufacturing errors or the like, the movable mirror 11 can be suppressed from moving when the movable mirror 11 moves in the Z-axis direction The target posture is tilted. Thus, according to the optical device 10, it is possible to suppress the decrease in optical characteristics caused by the unevenness of the shapes of the first torsion bars 145 and 155 and the second torsion bars 146 and 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 tilt of the movable mirror 11 from the target posture can also be suppressed. In addition, when there is a deviation in at least one of the length and thickness of the second torsion bar 146, the tilting of the movable mirror 11 from the target posture can also be suppressed. Similarly, the movable mirror 11 can be suppressed not only when the shape of the second torsion bar 146 is deviated, but also when at least one shape of the first torsion bar 145, 155 and the second torsion bar 156 is deviated. Tilt from the target posture.

In addition, in the optical device 10, when viewed from the Z-axis direction, the width of the first torsion bars 145 and 155 is wider than the width of the second torsion bars 146 and 156. As a result, the torsion spring constants of the first torsion bars 145 and 155 are preferably greater than the torsion spring constants of the second torsion bars 146 and 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 configured by the SOI substrate 50. In this way, in the optical device 10 formed by the MEMS technology, it is possible to suppress the reduction in optical characteristics caused by the unevenness of the shapes of the first torsion bars 145 and 155 and the second torsion bars 146 and 156.

In addition, the optical device 10 includes fixed comb-teeth electrodes 161 and 163, which are provided on the base 12, and a plurality of fixed comb teeth 161a and 163a, and movable comb-teeth electrodes 162 and 164, which are provided on the first The support portion 14 and the second elastic support portion 15 have a plurality of movable comb teeth 162a, 164a alternately arranged with the plurality of fixed comb teeth 161a, 163a. Thereby, the actuator portion 16 that can be used to move 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. With this, for example, the operation of the movable mirror 11 can be stabilized as compared with the case where only one elastic support portion is provided. In addition, for example, the total number of torsion bars can be reduced as compared with a case where there are more than three elastic support parts. As a result, the spring constant of each torsion bar can be ensured, and it is less likely to be affected by the unevenness of the torsion bar shape.

In the above, one embodiment of the present invention has been described, but the present invention is not limited to the above embodiment. The material and shape of each structure are not limited to the above-mentioned materials and shapes, and various materials and shapes can be used.

In the above embodiment, the width of the first torsion bar 145 is equal to the width of the second torsion bar 146, and the length of the first torsion bar 145 is shorter than the length of the second torsion bar 146. The torsion spring constant of the torsion bar 145 is greater than the torsion spring constant of the second torsion bar 146. Similarly, the first torsion bar 155 can be made equal to the width of the first torsion bar 155 and 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 The torsion spring constant is greater than the torsion spring constant of the second torsion bar 156.

Even when this situation is facilitated, as in the above-described embodiment, it is possible to suppress the decrease in optical characteristics caused by the unevenness of the shapes of the first torsion bars 145 and 155 and the second torsion bars 146 and 156. That is, as long as the torsion spring constant of the first torsion bar 145 is greater than the torsion spring constant 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 Choice. This aspect 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 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 have an arbitrary ring shape such as a rectangular ring shape or an octagonal ring shape. The frame portion 112 and the coupling portion 113 may be omitted. Each of the first beam portion 115b, the second beam portion 112b, and the third beam portion 113b may be formed in an arbitrary shape or may be omitted. In the above-described embodiment, the first torsion support portion is constituted by the plate-shaped first torsion bar 145, but the configuration of the first torsion support portion is not limited to this. The first torsion bar 145 may have any shape such as a bar shape. The first torsion support portion may be configured by connecting a plurality of (for example, two) torsion bars in series through the connection portion. These aspects are the same for the first torsion bar 155 and the second torsion bars 146 and 156 (second torsion support part). For example, the second torsion support portion may be configured by connecting a plurality of (for example, three) torsion bars in series via the connection portion.

In the above embodiment, the links 143 and 153 may be omitted. In this case, each of the first optical functional portion 17 and the second optical functional portion 18 may be constituted by an opening formed in the SOI substrate 50. Each of the first optical functional portion 17 and the second optical functional portion 18 may have an arbitrary cross-sectional shape such as a circular shape or an octagonal shape. The movable comb-shaped electrodes 162 and 164 may be provided on the movable mirror 11, for example, they may be arranged along the outer edge of the frame 112. The optical device 10 may replace the movable mirror 11 and include a movable portion provided with an optical function portion other than the mirror surface 11a. Examples of other optical functional sections include lenses. The actuator unit 16 is not limited to an electrostatic actuator, and may be, for example, a piezoelectric actuator, an electromagnetic actuator, or the like. The optical module 1 is not limited to those constituting FTIR, and may be those constituting other optical systems. The optical device 10 may be constituted by a substrate other than the SOI substrate 50. For example, it may be constituted by a substrate composed of only silicon.

1‧‧‧ Optical Module

2‧‧‧Mirror unit

3‧‧‧Spectroscope unit

4‧‧‧Optical resin

10‧‧‧Optical device

11‧‧‧movable mirror (movable part)

11a‧‧‧Mirror (Optical Function Department)

12‧‧‧Dock

12a‧‧‧Main

12b‧‧‧Main

12c‧‧‧ opening

13‧‧‧Drive Department

14‧‧‧First Flexible Support Department

15‧‧‧The second flexible support department

16‧‧‧Actuator Department

17‧‧‧First Optical Function Department

18‧‧‧ 2nd Optical Function Department

21‧‧‧Fixed mirror

21a‧‧‧Mirror

22‧‧‧Support

22a‧‧‧surface

22c‧‧‧Surface

23‧‧‧Sub mounting board

24‧‧‧Package

25‧‧‧Lead pin

26‧‧‧Wire

31‧‧‧Semi-reflective mirror

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

112‧‧‧frame

112a‧‧‧The second body

112b‧‧‧The second beam

113‧‧‧Link

113a‧‧‧The third body

113b‧‧‧The third beam

114‧‧‧Central

115‧‧‧Outer edge

115a‧‧‧The first body

115b‧‧‧First beam

116‧‧‧Bracket

117‧‧‧Bracket

121‧‧‧electrode pad

122‧‧‧electrode pad

141‧‧‧

141a‧‧‧End

141b‧‧‧End

141c‧‧‧Projection

142‧‧‧Link

143‧‧‧Link

144‧‧‧Bracket

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

146‧‧‧ 2nd torsion bar (2nd torsion support section)

147‧‧‧Electrode Support Department

151‧‧‧

151a‧‧‧End

151b‧‧‧End

151c‧‧‧Projection

152‧‧‧Link

153‧‧‧Link

154‧‧‧Bracket

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

156‧‧‧ 2nd torsion bar (2nd torsion support section)

157‧‧‧Electrode Support Department

161‧‧‧Fixed comb electrode

161a‧‧‧fixed comb

162‧‧‧movable comb electrode

162a‧‧‧movable comb

163‧‧‧Fixed comb electrode

163a‧‧‧fixed comb

164‧‧‧movable comb electrode

164a‧‧‧movable comb

241‧‧‧Bottom wall

242‧‧‧Side wall

243‧‧‧Top wall

243a‧‧‧surface

L0‧‧‧Measurement light

L1‧‧‧Determination light

P1‧‧‧Light path

P2‧‧‧Light path

R1‧‧‧Axis

R2‧‧‧Axis

S‧‧‧Space

1 is a longitudinal cross-sectional view of an optical module equipped with an optical device according to an embodiment. 2 is a top view of the optical device shown in FIG. FIG. 3 is a plan view showing an enlarged part of FIG. 2. FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 2. 5 is a graph showing the inclination of the mirror surface during the movement in Examples and Comparative Examples.

Claims (6)

An optical device comprising: a base having a main surface; a movable portion having an optical function portion; and an elastic support portion connected between the base and the movable portion, and capable of being along the movable portion The movable portion is supported by moving in a first direction perpendicular to the main surface; and the elastic supporting portion has: a rod; a first torsional supporting portion that extends along a second direction perpendicular to the first direction and is connected Between the rod and the movable portion; and a second torsional support portion extending along the second direction and connected between the rod and the base; the torsion spring constant of the first torsional support portion is greater than the first 2 The torsion spring constant of the torsion support part. The optical device according to claim 1, wherein the width of the first twist support portion is wider than the width of the second twist support portion when viewed from the first direction. The optical device according to claim 1 or 2, wherein the length of the first twist support portion is shorter than the length of the second twist support portion when viewed from the first direction. The optical device according to any one of claims 1 to 3, wherein the base, the movable portion, and the elastic support portion are composed of an SOI substrate. The optical device according to any one of claims 1 to 4, further comprising: a fixed comb-teeth electrode provided on the base and having a plurality of fixed comb teeth; and a movable comb-teeth electrode provided on the movable portion And at least one of the elastic support portions, and has a plurality of movable comb teeth alternately arranged with the plurality of fixed comb teeth. The optical device according to any one of claims 1 to 5, which includes only a pair of the above-mentioned elastic support portions.