JP2017173351A - MEMS device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique that allows for suppressing noise generated by a MEMS device without having to provide a sound-absorbing structure separately from a movable unit.SOLUTION: A MEMS device disclosed herein comprises a moveable section, a support section, and a coupling section that couples the movable section and the support section in such a way that the movable section is movable relative to the support section. The MEMS device has an air gap needed for moving the movable section and an air gap for releasing air provided in the proximity of sections where a movable range of the moveable section is large.SELECTED DRAWING: Figure 1

Description

  The present specification relates to a MEMS device.

  In some MEMS devices, noise generation during driving may be a problem. For example, in a MEMS scanner for a laser radar of a coaxial optical system used for an automobile collision prevention device or the like, this problem becomes significant.

  As shown in FIG. 22, the laser radar 300 mainly includes a laser 302, a half mirror 304, a MEMS scanner 306, and a light receiving unit 308. The laser beam 310 is reflected by the MEMS scanner 306 and scanned over the monitoring range. When the object 312 is irradiated with the laser beam 310, the reflected light 314 is reflected by the MEMS scanner 306 and the half mirror 304 and guided to the light receiving unit 308. The distance to the object 312 can be measured by using the time from the irradiation of the laser beam 310 until the reflected light 314 is received and the speed of light. By performing the distance measurement a plurality of times within the monitoring range, the distance and shape of the object 312 can be measured.

The MEMS scanner for laser radar as described above is required to have the following five performances.
(1) The mirror of the MEMS scanner needs to be large.
This is because the larger the mirror, the more reflected light from the object can be guided to the light receiving unit, and as a result, a highly sensitive laser radar can be realized.
(2) The MEMS scanner needs to be able to be driven with a large deflection angle.
This is because by operating at a large deflection angle, it is possible to irradiate laser light over a wide range, and as a result, a laser radar with a wide monitoring range can be realized.
(3) The MEMS scanner needs to have a high resonance frequency.
By having a high resonance frequency, it is possible to shorten the time for scanning the monitoring range, and it is possible to realize a laser radar having a high frame rate. For this reason, it becomes possible to detect an object that may collide without missing the object.
(4) The driving method of the MEMS scanner needs to be resonance driving.
In order to satisfy the above (1) and (3), it is necessary to increase the spring constant of the beam that supports the movable part of the MEMS scanner. Furthermore, in order to satisfy the requirement (2), it is necessary to operate the movable part with a large deflection angle. Resonance driving is desirable as a driving method for operating a MEMS scanner having a high spring constant beam at a large deflection angle. By resonance driving, the MEMS scanner can be driven with a force 1 / Q times that when the MEMS scanner is operated statically (where Q is a Q value, and the Q value is about 100 in a general MEMS scanner). This is because the driving power can be greatly reduced. From the above, it is desirable that the MEMS scanner is driven by resonance.
(5) The mirror chip used in the MEMS scanner needs to be small.
The mirror chip may be manufactured by processing a silicon wafer using a semiconductor process. When the mirror chip becomes large, the number of mirror chips that can be manufactured with one wafer decreases. As a result, the unit price of the mirror chip increases. Further, when the mirror chip becomes large, the MEMS scanner becomes large as a result. A laser radar or the like used for a car collision prevention device or the like is required to be as small as possible because it is installed in a limited space such as a passenger compartment. For this reason, the MEMS scanner is required to be as small as possible. From the above viewpoint, the mirror chip needs to be small.

  In order to satisfy all the above requirements (1) to (5), it is necessary to drive a large movable portion at a high speed and with a large deflection angle. When such a MEMS scanner was prototyped and driven, a large noise was generated. The laser radar is installed at a position close to a person, such as in the passenger compartment. For this reason, if the noise is large, it will cause discomfort to people in the passenger compartment. For this reason, reducing noise is a major issue.

  Patent Document 1 discloses a MEMS device including a movable part, a support part, and a connecting part that connects the movable part and the support part so that the movable part can move relative to the support part. In this MEMS device, noise generated when the movable portion moves relative to the support portion is suppressed by operating a silencing structure provided separately from the movable portion in reverse phase.

JP 2010-204336 A

  In the technique of Patent Document 1, it is necessary to provide a silencing structure for silencing noise separately from the movable part. A technique capable of suppressing noise generated by the MEMS device with a simpler configuration is expected.

(Effect of Claim 1)
The MEMS device disclosed in the present specification includes a movable portion, a support portion, and a connecting portion that connects the movable portion and the support portion so that the movable portion can move relative to the support portion. In the MEMS device, a gap necessary for moving the movable part and a gap for releasing air are provided in the vicinity of a place where the movable range of the movable part is large. Hereinafter, the reason for providing the gap will be described.

  As a result of measuring the MEMS scanner prototyped by the inventor of the present application, the largest noise was in the vicinity of the position where the movable range of the movable portion was the largest. From this, it is considered that noise is generated when the air pushed out by the movable part passes through a narrow gap.

  FIG. 23 illustrates a MEMS scanner 326 in which a swing plate 320 that is a movable portion is supported by a support frame 322 that is a support portion via a torsion beam 324 that is a connection portion. The swing plate 320 swings around the swing axis C. In the MEMS scanner 326, when the swing plate 320 is formed large and is driven at a high swing angle at a high speed, the speed of the end portion of the swing plate 320 becomes very high. As a result, as shown in FIG. 24, the rocking plate 320 pushes out a large amount of air 328. A large amount of air 328 to be pushed out is compressed between the swing plate 320 and the support frame 322 as shown in FIG. The compressed air 328 is injected from the gap between the swing plate 320 and the support frame 322 as shown in FIG.

  Since a large amount of compressed air 328 is ejected from a narrow gap, it is considered that the noise caused by the air has become very large. In order to reduce noise, in the MEMS device according to the first aspect, a gap having a width that allows air to move is provided in the vicinity of a location where the movable range of the movable portion is large, together with a gap necessary for the movable portion to move. By taking a large gap as described above, the amount of compressed air is reduced. Thereby, the speed of the air injected from the gap can be reduced. As a result, noise can be reduced. Particularly at a position where the movable range of the movable part is large, the amount of air pushed out is large. For this reason, a high noise reduction effect is acquired by providing a big space | gap in this position. According to the MEMS device of the first aspect, it is possible to suppress noise generated by the MEMS device with a simple configuration without separately providing a silencing structure.

(Effect of claim 2)
In the MEMS device described above, the movable part can swing around the swing axis with respect to the support part, and the distance between the movable part and the support part in a place where the movable range of the movable part with respect to the support part is large is supported. The movable range of the movable portion relative to the portion can be configured to be larger than the interval between the movable portion and the support portion at a small location.

  When the distance between the movable part and the support part is uniform and the distance between the movable part and the support part is only necessary for swinging as in the conventional MEMS device, the movable range of the movable part is large. As the speed increases, the velocity of the air generated from the gap in the vicinity increases (see FIG. 23). As a result, it causes a large noise. This is because the compression ratio of air between the support portion and the movable portion increases as the movable range of the movable portion with respect to the support portion increases. As illustrated in the MEMS device 332 of FIG. 28, by increasing the distance between the support unit 322 and the movable unit 320 in accordance with the movable range of the movable unit 320 with respect to the support unit 322, the vicinity of the movable unit 320 having a large movable range. The compression ratio of air in the air gap can be reduced. In the MEMS device described above, the gap between the movable part and the support part in the place where the movable range of the movable part is large is the gap necessary for moving the movable part (the movable part and the support part in the place where the movable range of the movable part is small). Since it functions as an air vent hole for noise reduction, the speed of air injected from all positions in the air gap can be reduced, and noise can be reduced. be able to.

(Effect of claim 3)
The above-mentioned MEMS device is configured such that the interval between the movable portion and the support portion changes gently between a location where the movable range of the movable portion relative to the support portion is small and a location where the movable range of the movable portion relative to the support portion is large. can do.

  In the MEMS device described above, since the interval between the movable portion and the support portion changes gently, it is possible to prevent the air flow pushed out by the movable portion from greatly fluctuating depending on the location. By adopting such a configuration, it is possible to suppress stress concentration due to a local load acting on the support portion due to the air flow.

(Effect of claim 4)
Alternatively, in the above MEMS device, the interval between the movable part and the support part may change rapidly between a place where the movable range of the movable part relative to the support part is small and a place where the movable range of the movable part relative to the support part is large. Can be configured.

  In the above MEMS device, by moving the distance between the movable portion and the support portion abruptly, most of the air flows in a place where the movable range of the movable portion relative to the support portion is large, and the movable range of the movable portion relative to the support portion. However, almost no air flows in small places. In general, the location where the movable range of the movable portion relative to the support portion is small is close to the location where the connecting portion that connects the movable portion and the support portion is connected to the support portion. A large load acts when moving. On the contrary, the location where the movable range of the movable portion relative to the support portion is large is away from the location where the connecting portion is connected to the support portion, and the support portion in the vicinity of such a location is not so large when moving the movable portion. The load does not work. According to the MEMS device described above, the load acting on the support portion due to the air flow pushed out by the movable portion is a location where the movable range of the movable portion relative to the support portion is large, that is, a location away from the location where the connecting portion connects to the support portion By acting on the load, the load acting on the support portion can be dispersed. It can suppress that stress concentration arises in a support part and can secure the intensity of a support part.

(Effect of Claim 5)
In the MEMS device, the width between the side surface closest to the movable portion and the side surface farthest from the movable portion in the direction along the swing axis of the support portion is in the direction perpendicular to the swing axis of the support portion. The width between the side surface closest to the movable part and the side surface farthest from the movable part can be larger.

  If an attempt is made to increase the distance between the support portion and the movable portion without increasing the chip size, the width of the support portion must be reduced accordingly, leading to a decrease in the strength and rigidity of the support portion. Therefore, in the MEMS device described above, the gap is increased and the width of the support portion is reduced at a location where a large noise is generated, and the gap is reduced and the width of the support portion is increased at a location where noise is not generated so much. Thus, noise is suppressed and the strength and rigidity of the support portion are ensured without increasing the chip size. Specifically, as illustrated in the MEMS device 330 in FIG. 27, between the end portion of the support portion 322 closest to the movable portion 320 and the end portion farthest from the movable portion in the direction along the swing axis C. The width A of the support portion 322 is configured to be larger than the width B between the end portion closest to the movable portion 320 and the end portion farthest from the movable portion in the direction perpendicular to the swing axis C. Thus, the strength in the vicinity of the connection point between the connecting portion 324 and the support portion 322 can be made equal to the structure of the prior art (see FIG. 23). Moreover, the area of the support part 322 in the vicinity of the connection point between the connecting part 324 and the support part 322 can be made equal to the structure of the prior art (see FIG. 23). Since the area that can be fixed is large, the MEMS device 330 can be firmly fixed in the vicinity of the connection point between the connecting portion 324 and the support portion 322. Since the MEMS device 330 can be fixed with the same strength as the conventional one, a Q value equivalent to that of the conventional MEMS device can be obtained. As a result, it can be driven with the same electric power as a conventional MEMS device. From the above, in this configuration, noise can be reduced without increasing the driving power of the MEMS device.

(Effect of claim 6)
Another MEMS device disclosed in the present specification includes a movable part, a support part, and a connecting part that connects the movable part and the support part so that the movable part can move relative to the support part. . In the MEMS device, the first ventilation hole is formed in the movable part. In addition, the ventilation hole as used in this specification means the through-hole which has a cross-sectional area which can reduce a noise when a movable part moves relatively with respect to a support part.

  In the above MEMS device, since the first ventilation hole is formed in the movable part, when the movable part moves relative to the support part, the air pushed out by the movable part through the first ventilation hole is released. Therefore, it is possible to prevent the air from being strongly compressed between the movable part and the support part. Accordingly, it is possible to suppress the generation of noise between the movable part and the support part when the movable part moves relative to the support part. In addition, since the air pushed out by the movable portion can be released by the first vent hole, it is not necessary to provide a gap for releasing air between the movable portion and the support portion. As a result, the same strength and area of the support as in the conventional MEMS device can be realized. For this reason, Q value equivalent to the conventional MEMS apparatus is realizable. Furthermore, since the movable portion is lightened by providing the hole, the spring constant of the support portion and the connecting portion for realizing the same resonance frequency can be reduced. Since the spring constant can be reduced while maintaining the Q value equivalent to the conventional one, the electric power for driving the MEMS device can be reduced. From the above, it is possible to reduce noise while reducing drive power.

(Effect of Claim 7)
In the MEMS device described above, the width of the first vent hole at a location where the movable range of the movable portion relative to the support portion is large is larger than the width of the first vent hole at a location where the movable range of the movable portion relative to the support portion is small. Can be configured.

  In the MEMS device described above, the width of the first vent hole at a location where the movable range of the movable portion relative to the support portion is large is larger than the width of the first vent hole at a location where the movable range of the movable portion relative to the support portion is small. Therefore, the air which has a large influence on noise and where the movable range of the movable portion is large can be transmitted. For this reason, in said MEMS apparatus, the noise reduction effect equivalent to the structure of Claim 6 can be maintained. Further, since the area of the movable portion other than the first vent hole can be increased at a location where the movable range of the movable portion relative to the support portion is small, it is possible to ensure the rigidity of the movable portion. Furthermore, by increasing the width of the first vent at a location where the movable range of the movable portion is large, the moment of inertia of the movable portion can be reduced, and the support portion and the connecting portion for realizing the same resonance frequency can be reduced. The spring constant can be reduced. Since the spring constant can be reduced while maintaining the Q value equivalent to the conventional one, the electric power for driving the MEMS device can be reduced. From the above, it is possible to reduce noise while reducing drive power. In addition, since the air pushed out by the movable part can be released by the first vent hole, it is not necessary to change the distance between the movable part and the support part depending on the location, and the width to be processed during etching is made uniform. Can do. Generation of the microloading effect can be suppressed, and the movable portion and the support portion can be processed with high accuracy.

(Effect of Claim 8)
Another MEMS device disclosed in the present specification includes a movable part, a support part, and a connecting part that connects the movable part and the support part so that the movable part can move relative to the support part. . In the MEMS device, a second ventilation hole is formed in the support portion.

  In the above MEMS device, since the second ventilation hole is formed in the support part, when the movable part moves relative to the support part, the air pushed out by the movable part through the second ventilation hole is released. Therefore, it is possible to prevent the air from being strongly compressed between the movable part and the support part. Accordingly, it is possible to suppress the generation of noise between the movable part and the support part when the movable part moves relative to the support part. In addition, since the air pushed out by the movable part can be released by the second vent hole, it is not necessary to change the distance between the movable part and the support part depending on the location, and the width to be processed during etching is made uniform. Can do. Generation of the microloading effect can be suppressed, and the movable portion and the support portion can be processed with high accuracy.

(Effect of Claim 9)
Said MEMS apparatus can be comprised so that a connection part may be equipped with the several torsion beam. The torsion beam in the present specification refers to a beam-like member that undergoes torsional deformation when the movable part moves relative to the support part.

  Although details will be described later in Example 8, when the connecting portion is formed of a plurality of torsion beams, the required movable portion is more compared to the case where the connecting portion is formed of a single torsion beam. The length of the torsion beam can be shortened while ensuring the resonance frequency and the strength of the torsion beam. When the chip area of the MEMS device is constant, in this configuration, the area of the support portion can be made larger than that of the conventional MEMS device. As a result, since the rigidity of the support portion can be increased, the Q value of the MEMS device can be increased. As a result, the driving power of the MEMS device can be reduced.

(Effect of Claim 10)
In the above MEMS device, a plurality of torsion beams are arranged in the same plane, and are integrated at a connection portion with the movable portion, and a third vent hole is formed at the integrated connection portion. Can be configured.

  When the connecting part is composed of a plurality of torsion beams arranged in the same plane, the torsion beam at a position away from the rotation axis has a larger movable range of the movable part than the beam near the rotation axis. , Connected to the movable part. In such a beam, compared to the torsion beam close to the rotation axis, the connection part of the torsion beam to the movable part moves greatly with respect to the support part together with the movable part. There is a risk that the air is strongly compressed between the parts and generates a large noise. According to the MEMS device, a plurality of torsion beams are integrated at the connection portion with the movable portion, and the third ventilation hole is formed at the integrated connection portion. Ventilation holes larger than the distance between the beams can be formed. Thus, it is possible to prevent the air from being strongly compressed between the connection portion of the torsion beam and the movable portion and the support portion, and to reduce noise generated by the air pushed out by the connection portion of the movable portion and the torsion beam.

(Effect of Claim 11)
In the MEMS device described above, the third vent hole in the portion where the movable range of the plurality of torsion beams with respect to the support portion is large, and the third vent hole in the portion where the movable range of the plurality of torsion beams with respect to the support portion is small. It can be configured to be larger than the width.

  In the above MEMS device, the air that has a large movable range is pushed out by increasing the width of the third vent hole in the beam connecting portion where the influence of noise is large and the movable range is large. Can be transmitted. For this reason, in said MEMS apparatus, the noise reduction effect equivalent to the structure of Claim 10 is maintainable. Further, in the MEMS device described above, the area of the beam connection portion other than the third ventilation hole is reduced by reducing the width of the third ventilation hole in the beam connection portion where the movable range is small. Since it can be increased, the rigidity of the beam connecting portion can be ensured.

(Effect of Claim 12)
The MEMS device may be configured such that a spacing between the torsion beam closest to the support portion among the plurality of torsion beams and the support portion is substantially equal to a spacing between adjacent torsion beams of the plurality of torsion beams. it can.

  According to the MEMS device described above, it is possible to suppress the generation of the microloading effect when processing a plurality of torsion beams, and to process the plurality of torsion beams with high accuracy. Details of microloading will be described in Example 10.

(Effect of Claim 13)
The above MEMS device can be configured to include a mirror fixed to the movable part.

  The above MEMS device can be used as an optical deflection device. According to the MEMS device described above, it is possible to suppress noise generated during operation of the optical deflection device.

(Effect of Claim 14)
In the above MEMS device, the movable portion includes the second movable portion, the second support portion, and the second movable portion and the second support portion so that the second movable portion can move relative to the second support portion. A second connecting portion to be connected is further provided, and the connecting portion is configured such that the second support portion is connected between the second support portion and the support portion so as to be movable relative to the support portion. be able to.

  The MEMS device described above can be used as a device in which the second movable portion can move relative to the support portion with two degrees of freedom. According to said MEMS apparatus, in such an apparatus, it can suppress that a noise generate | occur | produces between a 2nd support part and a support part.

(Effect of Claim 15)
In the MEMS device described above, the width of the second support portion at a location where the movable range of the second support portion relative to the support portion is large is larger than the width of the second support portion where the movable range of the second support portion relative to the support portion is small. It can be configured to be small.

  According to the MEMS device described above, it is possible to ensure the interval between the second support portion and the support portion without reducing the shape of the support portion. Generation of noise between the second support portion and the support portion can be suppressed while securing the rigidity and strength of the support portion.

(Effect of claim 16)
The MEMS device is configured to further include a third support part and a third connection part that connects the support part and the third support part so that the support part can move relative to the third support part. can do.

  According to said MEMS apparatus, a movable part can be utilized as an apparatus which can move relatively with 2 degrees of freedom with respect to a 3rd support part. According to the MEMS device described above, in such a device, generation of noise between the movable portion and the support portion can be suppressed.

(Effect of Claim 17)
Said MEMS apparatus can be comprised so that the width | variety of the movable part in the location where the movable range of the movable part with respect to a support part is large is smaller than the width | variety of the movable part in the location where the movable range of the movable part with respect to a support part is small. .

  According to the MEMS device described above, it is possible to ensure the interval between the movable portion and the support portion without reducing the shape of the support portion. Generation of noise between the movable portion and the support portion can be suppressed while securing the rigidity and strength of the support portion.

1 is a plan view showing a schematic configuration of a MEMS device 2 of Example 1. FIG. It is the longitudinal cross-sectional view seen in the II-II cross section of FIG. FIG. 6 is a plan view illustrating a schematic configuration of a MEMS device 22 according to a second embodiment. FIG. 6 is a plan view illustrating a schematic configuration of a MEMS device 32 according to a third embodiment. FIG. 10 is a plan view illustrating a schematic configuration of a MEMS device 42 according to a fourth embodiment. FIG. 10 is a plan view illustrating a schematic configuration of a MEMS device 52 according to a fifth embodiment. FIG. 10 is a plan view illustrating a schematic configuration of a MEMS device 62 according to a sixth embodiment. FIG. 10 is a plan view illustrating a schematic configuration of a MEMS device 72 according to a seventh embodiment. FIG. 10 is a plan view illustrating a schematic configuration of a MEMS device 82 according to an eighth embodiment. It is a perspective view which shows typically the case where the rocking | swiveling board P is supported by the torsion beams BR and BL. It is a perspective view which shows typically the case where the rocking plate P is supported by the torsion beam group BRn, BLn. FIG. 10 is a plan view showing a schematic configuration of a MEMS device 112 of Example 9. FIG. 10 is a plan view showing a schematic configuration of a MEMS device 122 of Example 10. FIG. 20 is a plan view illustrating a schematic configuration of a MEMS device 132 according to an eleventh embodiment. FIG. 20 is a plan view illustrating a schematic configuration of a MEMS device 142 according to a twelfth embodiment. FIG. 20 is a plan view showing a schematic configuration of a MEMS device 162 of Example 13. FIG. 22 is a plan view showing a schematic configuration of a MEMS device 172 of Example 14; FIG. 22 is a plan view showing a schematic configuration of a MEMS device 182 of Example 15. FIG. 22 is a plan view showing a schematic configuration of a MEMS device 192 of Example 16. FIG. 20 is a plan view showing a schematic configuration of a MEMS device 212 of Example 17. FIG. 20 is a plan view showing a schematic configuration of a MEMS device 222 of Example 18. 2 is a diagram schematically showing a schematic configuration of a general laser radar 300. FIG. It is a top view which shows the structure of the outline of the MEMS scanner 326 of a prior art. It is the longitudinal cross-sectional view seen in the XXIV-XXIV cross section of FIG. 23, and is a figure explaining the generation | occurrence | production mechanism of the noise in the MEMS scanner 326 of a prior art. It is the longitudinal cross-sectional view seen in the XXIV-XXIV cross section of FIG. 23, and is a figure explaining the generation | occurrence | production mechanism of the noise in the MEMS scanner 326 of a prior art. It is the longitudinal cross-sectional view seen in the XXIV-XXIV cross section of FIG. 23, and is a figure explaining the generation | occurrence | production mechanism of the noise in the MEMS scanner 326 of a prior art. 3 is a plan view showing a schematic configuration of a MEMS device 330. FIG. 3 is a plan view showing a schematic configuration of a MEMS device 332; FIG. FIG. 40 is a plan view showing a schematic configuration of a MEMS device 242 of Example 19;

Example 1
1 and 2 show a MEMS device 2 of the present embodiment. The MEMS device 2 includes a support frame 4 (an example of a support part), a swing plate 6 (an example of a movable part), a mirror 8, and torsion beams 10a and 10b (an example of a connection part). The permanent magnet 12 and the electromagnets 14a and 14b are provided.

  The support frame 4, the swing plate 6, and the torsion beams 10a and 10b are formed by selectively etching a silicon wafer made of single crystal silicon. The support frame 4, the rocking plate 6, and the torsion beams 10a and 10b are integrally formed without a seam.

  The support frame 4 is formed in a shape surrounding the swing plate 6 and the torsion beams 10a and 10b when the MEMS device 2 is viewed from above.

  The swing plate 6 is formed in a rectangular flat plate shape when the MEMS device 2 is viewed from above. The swing plate 6 is disposed inside the support frame 4. The swing plate 6 is supported so as to be swingable about the swing axis C with respect to the support frame 4 via torsion beams 10a and 10b. In this embodiment, the direction along the swing axis C is the X axis, the direction orthogonal to the swing plate 6 is the Z axis, and the direction orthogonal to the X axis and the Z axis is the Y axis.

  The mirror 8 is formed by evaporating a metal such as AL on the surface of the swing plate 6. The mirror 8 reflects light incident from the upper surface side of the MEMS device 2. When the swing plate 6 swings around the swing axis C, the reflection angle of the mirror 8 changes. That is, the MEMS device 2 can operate as an optical deflection device.

  The torsion beams 10a and 10b are linear members extending along the X-axis direction. The torsion beams 10a and 10b are formed in a shape with high rigidity against bending and low rigidity against torsion. The torsion beams 10a and 10b support the swing plate 6 from both sides in the X-axis direction (that is, from both sides in the direction along the swing axis C). The torsion beam 10 a supports one end (the left end in FIG. 1) along the swing axis C of the swing plate 6. The torsion beam 10 b supports the other end portion (the right end portion in FIG. 1) along the swing axis C of the swing plate 6. When the swing plate 6 swings, the torsion beams 10a and 10b are torsionally deformed.

  A gap 16 exists between the swing plate 6 and the support frame 4. The gap 16 has a width La between the side surface 6a at the end in the Y-axis direction of the swing plate 6 and the side surface 4a of the support frame 4 facing the side surface 6a when the MEMS device 2 is viewed from above. Have. Further, the gap 16 has a width between the side surface 6b at the end in the X-axis direction of the swing plate 6 and the side surface 4b of the support frame 4 facing the side surface 6b when the MEMS device 2 is viewed from above. Lb. In the MEMS device 2 of the present embodiment, the width La between the side surface 6a of the end portion of the swing plate 6 in the Y-axis direction and the side surface 4a of the support frame 4 is the side surface of the end portion of the swing plate 6 in the X-axis direction. It is formed larger than the width Lb between 6b and the side surface 4b of the support frame 4. In the MEMS device 2 of this embodiment, the distance between the swing plate 6 and the support frame 4 is such that the movable range of the swing plate 6 with respect to the support frame 4 is small and the movable range of the swing plate 6 with respect to the support frame 4 is small. It can be said that it changes rapidly between large parts.

  A gap 18 exists between the torsion beams 10 a and 10 b and the support frame 4. The gap 18 has widths Lc and Ld between the side surfaces 10c and 10d in the Y-axis direction of the torsion beams 10a and 10b and the side surfaces 4c and 4d of the support frame 4 facing the side surfaces 10c and 10d. In the MEMS device 2 of the present embodiment, the widths Lc and Ld between the side surfaces 10c and 10d of the torsion beams 10a and 10b in the Y-axis direction and the side surfaces 4c and 4d of the support frame 4 are The width La between the side surface 6a of the end portion and the side surface 4a of the support frame 4 and the width Lb between the side surface 6b of the end portion of the swing plate 6 in the X-axis direction and the side surface 4b of the support frame 4 are small. Is formed.

The permanent magnet 12 is a permanent magnet made of a neodymium magnet (Nd ₂ Fe ₁₄ B), a samarium cobalt magnet (SmCo ₅ (1-5 system), Sm ₂ Co ₁₇ (2-17 system), etc.), a ferrite magnet, or the like. It is. The permanent magnet 12 is fixed to the center of the back surface of the swing plate 6. As shown in FIG. 1, the permanent magnet 12 is disposed at a position overlapping the swing axis C when the MEMS device 2 is viewed from above. As shown in FIG. 2, the permanent magnet 12 is fixed to the swing plate 6 in a posture in which the polarity direction is orthogonal to the swing plate 6. In the present embodiment, the N pole of the permanent magnet 12 is disposed on the side close to the swing plate 6, and the S pole is disposed on the side far from the swing plate 6.

  The electromagnets 14a and 14b are formed by winding a coil around an iron core. The electromagnets 14a and 14b are arranged so as to sandwich the permanent magnet 12 of the swing plate 6 from the outside of the support frame 4 in the Y-axis direction.

  For example, when a current is passed through the electromagnets 14a and 14b so that the electromagnet 14a has an N pole and the electromagnet 14b has an S pole, a magnetic field in the direction from the electromagnet 14b to the electromagnet 14a is applied to the permanent magnet 12 of the swing plate 6. Works. As a result, torque is applied to the permanent magnet 12 in such a direction that the S pole approaches the electromagnet 14a and the N pole approaches the electromagnet 14b. By this torque, the swing plate 6 swings in a direction in which the end portion on the electromagnet 14a side rises and the end portion on the electromagnet 14b side descends. Thereby, the reflection angle of the mirror 8 changes.

  Conversely, when a current is passed through the electromagnets 14a and 14b so that the electromagnet 14a becomes the S pole and the electromagnet 14b becomes the N pole, the permanent magnet 12 of the swing plate 6 is moved in the direction from the electromagnet 14a to the electromagnet 14b. A magnetic field acts. As a result, torque is applied to the permanent magnet 12 in a direction to bring the south pole closer to the electromagnet 14b and the north pole closer to the electromagnet 14a. By this torque, the swing plate 6 swings in a direction in which the end portion on the electromagnet 14b side rises and the end portion on the electromagnet 14a side descends. Thereby, the reflection angle of the mirror 8 changes.

  In the present embodiment, the swing plate 6 is swung using a magnetic force acting between the permanent magnet 12 and the electromagnets 14a and 14b. With such a configuration, it is not necessary to supply current to the swing plate 6 and electrical wiring from the support frame 4 to the swing plate 6 via the torsion beams 10a and 10b is not necessary. By setting it as such a structure, the cross section of the torsion beams 10a and 10b can be formed smaller.

  When the swing plate 6 swings, air is compressed between the side surface 6a of the end portion of the swing plate 6 in the Y-axis direction and the side surface 4a of the support frame 4 to generate noise. At this time, if the distance La between the side surface 6a of the end portion in the Y-axis direction of the swing plate 6 and the side surface 4a of the support frame 4 is formed small, the air is strongly compressed and a large noise is generated. . In order to suppress such air compression, it is preferable to increase the area of the gap 16 between the swing plate 6 and the support frame 4 and the gap 18 between the torsion beams 10a and 10b and the support frame 4. However, if the areas of the gaps 16 and 18 are simply formed large, the area of the support frame 4 must be reduced accordingly, and the strength and rigidity of the support frame 4 are reduced. As a result, the Q value of the MEMS device 2 decreases, and the power for operating the swing plate 6 by a desired angle increases. In the MEMS device 2 of the present embodiment, the distance La between the side surface 6a of the end in the Y-axis direction of the rocking plate 6 that generates noise and the side surface 4a of the support frame 4 is a torsion beam 10a that does not generate much noise. It is formed larger than the widths Lc and Ld between the side surfaces 10c and 10d in the Y-axis direction of 10b and the side surfaces 4c and 4d of the support frame 4. By adopting such a configuration, noise is generated between the side surface 6a of the end of the swing plate 6 in the Y-axis direction and the side surface 4a of the support frame 4 while ensuring the rigidity and strength of the support frame 4. Can be suppressed.

  Similarly, when the swing plate 6 swings, air is compressed between the side surface 6b of the end portion of the swing plate 6 in the X-axis direction and the side surface 4b of the support frame 4 to generate noise. In the MEMS device 2 of the present embodiment, the distance Lb between the side surface 6b at the end in the X-axis direction of the rocking plate 6 that generates noise and the side surface 4b of the support frame 4 has a torsion beam 10a that does not generate much noise. It is formed larger than the widths Lc and Ld between the side surfaces 10c and 10d in the Y-axis direction of 10b and the side surfaces 4c and 4d of the support frame 4. With such a configuration, noise is generated between the side surface 6b of the end portion of the swing plate 6 in the X-axis direction and the side surface 4b of the support frame 4 while ensuring the rigidity and strength of the support frame 4. Can be suppressed.

  When the oscillating plate 6 oscillates, the side surface 6a at the end in the Y-axis direction of the oscillating plate 6 is larger than the side surface 6b at the end in the X-axis direction of the oscillating plate 6. Because the distance from is large, it swings at high speed and with large amplitude. For this reason, air is more easily compressed on the side surface 6a at the end in the Y-axis direction of the swing plate 6 than on the side surface 6b at the end in the X-axis direction of the swing plate 6, and a large noise is likely to occur. In the MEMS device 2 of the present embodiment, the interval La between the side surface 6a of the end portion in the Y-axis direction of the swing plate 6 and the side surface 4a of the support frame 4 that are likely to generate large noises is unlikely to generate so much noise. It is formed larger than the distance Lb between the side surface 6b at the end of the swinging plate 6 in the X-axis direction and the side surface 4b of the support frame 4. By adopting such a configuration, it is possible to suppress the generation of large noise between the swing plate 6 and the support frame 4 while ensuring the rigidity and strength of the support frame 4.

(Example 2)
FIG. 3 shows the MEMS device 22 of the present embodiment. The MEMS device 22 has the same configuration as the MEMS device 2 of the first embodiment shown in FIGS. Below, only the difference between the MEMS device 22 and the MEMS device 2 of the first embodiment will be described.

  In the MEMS device 22 of the present embodiment, when the MEMS device 22 is viewed from above, the side surface 4b of the support frame 4 is inclined with respect to the side surface 6b of the end portion in the X-axis direction of the swing plate 6. The distance Lb between the side surface 6b of the end portion of the rocking plate 6 in the X-axis direction and the side surface 4b of the support frame 4 increases as the position becomes farther from the rocking shaft C. In the MEMS device 22 of the present embodiment, the distance between the swing plate 6 and the support frame 4 is such that the movable range of the swing plate 6 relative to the support frame 4 is small and the movable range of the swing plate 6 relative to the support frame 4 is small. It can be said that there is a gradual change between large parts.

  When the swing plate 6 swings, the side surface 6b of the end portion in the X-axis direction of the swing plate 6 swings at a low speed and with a small amplitude at a position close to the swing shaft C. In a distant position, it vibrates at high speed and with a large amplitude. For this reason, the side surface 6b of the end portion in the X-axis direction of the swing plate 6 hardly generates a large noise at a position close to the swing axis C, and easily generates a large noise at a position far from the swing axis C. . In the MEMS device 22 of the present embodiment, the distance Lb between the side surface 6b of the end portion in the X-axis direction of the swing plate 6 and the side surface 4b of the support frame 4 increases as the position becomes farther from the swing shaft C. It is formed as follows. With such a configuration, a large noise is generated between the side surface 6b of the end portion of the swing plate 6 in the X-axis direction and the side surface 4b of the support frame 4 while ensuring the rigidity and strength of the support frame 4. This can be suppressed.

(Example 3)
FIG. 4 shows the MEMS device 32 of this embodiment. The MEMS device 32 has the same configuration as the MEMS device 2 of the first embodiment shown in FIGS. Below, only the difference between the MEMS device 32 and the MEMS device 2 of the first embodiment will be described.

  In the MEMS device 22 of the present embodiment, the swing plate 6 is formed in a hexagonal flat plate shape when the MEMS device 22 is viewed from above. Therefore, when the MEMS device 22 is viewed from above, the side surface 6b of the swing plate 6 is inclined with respect to the side surface 4b of the support frame 4, and the side surface 6b of the swing plate 6 and the side surface of the support frame 4 The distance Lb between 4b increases as the distance from the swing axis C increases. By adopting such a configuration, as in the MEMS device 22 of the second embodiment, the rigidity and strength of the support frame 4 are ensured, and a large space is provided between the side surface 6b of the swing plate 6 and the side surface 4b of the support frame 4. Generation of noise can be suppressed.

Example 4
FIG. 5 shows the MEMS device 42 of the present embodiment. The MEMS device 42 has the same configuration as the MEMS device 2 of the first embodiment shown in FIGS. 1 and 2. Below, only the difference between the MEMS device 42 and the MEMS device 2 of the first embodiment will be described.

  In the MEMS device 42 of the present embodiment, the width La between the side surface 6a of the end portion of the swing plate 6 in the Y-axis direction and the side surface 4a of the support frame 4, and the side surface of the end portion of the swing plate 6 in the X-axis direction. The width Lb between 6b and the side surface 4b of the support frame 4 is formed to have the same size.

  Further, in the MEMS device 42 according to the present embodiment, the swing plate 6 is formed with a vent hole 44 (which is an example of a first vent hole). The vent hole 44 is formed in the vicinity of the end portion of the swing plate 6 in the Y-axis direction. The vent hole 44 is formed in a rectangular shape having a longitudinal direction in the X-axis direction when the MEMS device 42 is viewed from above. The vent hole 44 extends from the vicinity of one end of the swing plate 6 in the X-axis direction to the vicinity of the other end.

  In the MEMS device 42 of the present embodiment, when the swing plate 6 swings, air passes through the vent hole 44, so that the air is prevented from being strongly compressed between the swing plate 6 and the support frame 4. And generation | occurrence | production of a big noise can be suppressed. In this case, even if the area of the gap 16 between the swing plate 6 and the support frame 4 or the gap 18 between the torsion beams 10a and 10b and the support frame 4 is reduced, no significant noise is generated. By increasing the area, the strength and rigidity of the support frame 4 can be ensured.

  In the MEMS device 42 of the present embodiment, a vent hole 44 is formed in the vicinity of the end portion of the swing plate 6 in the Y-axis direction. Since the end of the swing plate 6 in the Y-axis direction swings at a high speed and with a large amplitude when the swing plate 6 swings, a large noise is likely to be generated. Like the MEMS device 42 of the present embodiment, by forming the vent hole 44 in the vicinity of the end portion of the swing plate 6 in the Y-axis direction, it is possible to suppress the generation of large noise.

(Example 5)
FIG. 6 shows a MEMS device 52 of the present embodiment. The MEMS device 52 has the same configuration as the MEMS device 42 of the fourth embodiment shown in FIG. Below, only the difference between the MEMS device 42 and the MEMS device 42 of the fourth embodiment will be described.

  In the MEMS device 52 of this embodiment, the vent hole 44 is formed in the vicinity of the end portion of the swing plate 6 in the X-axis direction. The vent hole 44 is formed in a rectangular shape having a longitudinal direction in the Y-axis direction when the MEMS device 52 is viewed from above. The vent hole 44 extends from the vicinity of one end of the swing plate 6 in the Y-axis direction to the vicinity of the other end.

  In the MEMS device 52 of the present embodiment, when the swing plate 6 swings, air passes through the vent hole 44, thereby preventing air from being strongly compressed between the swing plate 6 and the support frame 4. And generation | occurrence | production of a big noise can be suppressed. According to the MEMS device 52 of the present embodiment, as with the MEMS device 42 of the fourth embodiment, it is possible to suppress the generation of large noise while ensuring the strength and rigidity of the support frame 4.

(Example 6)
FIG. 7 shows a MEMS device 62 of the present embodiment. The MEMS device 62 has the same configuration as that of the MEMS device 42 according to the fourth embodiment shown in FIG. Below, only the difference between the MEMS device 62 and the MEMS device 42 of the fourth embodiment will be described.

  In the MEMS device 62 of the present embodiment, when the vent hole 44 is viewed from above the MEMS device 62 in plan view, the two bases are along the X-axis direction, and the length of the base farther from the swing axis C is the length. However, it is formed in a trapezoidal shape longer than the length of the bottom side closer to the swing axis C. That is, the width of the vent hole 44 in the X-axis direction is narrower as it is closer to the swing axis C and wider as it is farther from the swing axis C.

  In the MEMS device 62 of the present embodiment, it is possible to suppress the generation of noise while ensuring the strength and rigidity of the support frame 4 as in the MEMS device 42 of the fourth embodiment. Further, in the MEMS device 62 of the present embodiment, as in the MEMS device 42 of the fourth embodiment, a large noise is generated by forming the vent hole 44 in the vicinity of the end portion of the swing plate 6 in the Y-axis direction. Can be suppressed.

  In the MEMS device 62 of the present embodiment, the width of the vent hole 44 in the X-axis direction is narrower as it is closer to the swing axis C and wider as it is farther from the swing axis C. When the vent hole 44 is formed in the swing plate 6, the strength and rigidity of the swing plate 6 are lower than when the vent hole 44 is not formed. In the MEMS device 42 of the present embodiment, the width of the vent hole 44 in the X-axis direction is narrower as it is closer to the swing axis C (that is, as it is farther from the end in the Y-axis direction of the swing plate 6). The distance from C is wider (ie, the closer to the end in the Y-axis direction of the swing plate 6), the wider. The amount of air to be pushed out can be reduced by making the vent hole larger at a position where the driving speed is faster and the air to be pushed out is larger. For this reason, noise can be effectively suppressed. In addition, by enlarging a portion other than the hole of the swing plate 6, it is easy to ensure the strength and rigidity of the swing plate 6. As a result, since a high Q value can be obtained, the swing plate 6 can be driven with a small electric power.

(Example 7)
FIG. 8 shows a MEMS device 72 of this embodiment. The MEMS device 72 has the same configuration as the MEMS device 52 of the fifth embodiment shown in FIG. Below, only the difference between the MEMS device 72 and the MEMS device 52 of the fifth embodiment will be described.

  In the MEMS device 72 of the present embodiment, the vent hole 44 is disposed in the vicinity of the corner of the swing plate 6 when the MEMS device 72 is viewed from above, and one side is the X axis of the swing plate 6. It is formed in a triangular shape that is parallel to the side surface of the end portion in the direction and the other side is parallel to the side surface of the end portion in the Y-axis direction of the swing plate 6. That is, the width of the vent hole 44 in the X-axis direction is wider as it is farther from the swing axis C (that is, closer to the end of the swing plate 6 in the Y-axis direction) and closer to the swing axis C (that is, The farther from the end of the swing plate 6 in the Y-axis direction, the narrower. Further, the width of the vent hole 44 in the Y-axis direction is wider as it is closer to the end of the swing plate 6 in the X-axis direction, and is narrower as it is farther from the end of the swing plate 6 in the X-axis direction.

  In the MEMS device 72 of the present embodiment, by forming the vent hole 44 in the swing plate 6, it is possible to suppress the generation of noise while ensuring the strength and rigidity of the support frame 4. Further, in the MEMS device 72 of the present embodiment, it is possible to suppress the generation of a large noise by forming the vent hole 44 in the vicinity of the end portion of the swing plate 6 in the Y-axis direction. Furthermore, in the MEMS device 72 of the present embodiment, it is possible to suppress the generation of large noise by forming the vent hole 44 in the vicinity of the end portion of the swing plate 6 in the X-axis direction.

  In order to suppress noise, the vent hole 44 is preferably enlarged in the vicinity of the end portion in the Y-axis direction of the swing plate 6 having a high moving speed. However, when the vent hole 44 is formed in the swing plate 6, the strength and rigidity of the swing plate 6 are lower than when the vent hole 44 is not formed. In the MEMS device 72 of the present embodiment, the width of the vent hole 44 in the X-axis direction is wider as it is closer to the end of the swing plate 6 in the Y-axis direction, and the farther from the end of the swing plate 6 in the Y-axis direction. It is formed to be narrow. By setting it as such a structure, it can suppress generating a big noise, ensuring the intensity | strength and rigidity of the rocking | fluctuation board 6. FIG.

(Example 8)
FIG. 9 shows a MEMS device 82 of the present embodiment. The MEMS device 82 has the same configuration as the MEMS device 2 of the first embodiment shown in FIGS. 1 and 2. Below, only the difference between the MEMS device 82 and the MEMS device 2 of the first embodiment will be described.

  In the MEMS device 82 of the present embodiment, the swing plate 6 is supported so as to be swingable around the swing axis C with respect to the support frame 4 via torsion beam groups 84a and 84b (an example of a connecting portion). Has been. The torsion beam groups 84a and 84b support the swing plate 6 from both sides in the X-axis direction (that is, from both sides in the direction along the swing axis C). The torsion beam group 84 a supports one end portion (the left end portion in FIG. 9) along the swing axis C of the swing plate 6. The torsion beam group 84 b supports the other end portion (the right end portion in FIG. 9) along the swing axis C of the swing plate 6. When the swing plate 6 swings, the torsion beam groups 84a and 84b are torsionally deformed.

  The torsion beam group 84a includes two straight torsion beams 86a and 88a and ten bent torsion beams 90a, 92a, 94a, 96a, 98a, 100a, 102a, 104a, 106a, and 108a. The torsion beam group 84b includes two straight torsion beams 86b and 88b and ten bent torsion beams 90b, 92b, 94b, 96b, 98b, 100b, 102b, 104b, 106b and 108b. Straight torsion beams 86a, 86b, 88a, 88b and bent torsion beams 90a, 90b, 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, 106a, 106b , 108a, 108b all have a rectangular cross section and are arranged in the same plane (in the XY plane).

  The straight torsion beams 86a and 88a extend in a straight line and are arranged in parallel with each other along the swing axis C. The linear torsion beams 86a and 88a are disposed at symmetrical positions with the swing axis C interposed therebetween when the MEMS device 82 is viewed from above. The straight torsion beams 86a and 88a are both arranged away from the swing axis C. The linear torsion beams 86b and 88b extend in a straight line and are arranged in parallel to each other along the swing axis C. The straight torsion beams 86b and 88b are arranged at symmetrical positions with the swing axis C in between when the MEMS device 82 is viewed from above. The straight torsion beams 86b and 88b are both arranged away from the swing axis C.

  At the connection portion of the straight torsion beams 86a, 86b, 88a, 88b with the support frame 4 and the connection portion with the swing plate 6, the side surfaces of the straight torsion beams 86a, 86b, 88a, 88b on the side close to the swing axis C are The side surface of the straight torsion beams 86a, 86b, 88a, 88b far from the swing axis C is formed through a concave fillet shape. 4 or a shape connected to the side surface of the swing plate 6. In other words, the cross-sectional area of the straight torsion beams 86a, 86b, 88a, 88b increases as the distance from the center of the cross section to the swing axis C increases as the support frame 4 is approached. It is formed in an increasing shape. In addition, the straight torsion beams 86a, 86b, 88a, 88b increase in cross-sectional area as they approach the swing plate 6 at the connection portions with the swing plate 6, and the distance from the center of the cross section to the swing axis C. Is formed in an increasing shape. By adopting such a configuration, a cross-sectional area required at the connection portion with the support frame 4 and / or the swing plate 6 in order to relieve stress concentration in the linear torsion beams 86a, 86b, 88a, 88b is secured. However, the linear torsion beams 86a, 86b, 88a, 88b can be arranged at positions close to the swing axis C to reduce the tensile stress acting on the linear torsion beams 86a, 86b, 88a, 88b.

  The bent torsion beams 90a, 94a, 98a, 102a, and 106a are sequentially arranged adjacent to each other on the side farther from the swing axis C when viewed from the straight torsion beam 86a. The bent torsion beams 92a, 96a, 100a, 104a, and 108a are sequentially arranged adjacent to each other on the side farther from the swing axis C when viewed from the straight torsion beam 88a. The bending torsion beams 90a, 94a, 98a, 102a, 106a and the corresponding bending torsion beams 92a, 96a, 100a, 104a, 108a are symmetrical with respect to the oscillation axis C when the MEMS device 82 is viewed from above. It is arranged in the position. The bent torsion beams 90b, 94b, 98b, 102b, and 106b are sequentially arranged adjacent to each other on the side farther from the swing axis C when viewed from the straight torsion beam 86b. The bent torsion beams 92b, 96b, 100b, 104b, and 108b are sequentially arranged adjacent to each other on the side far from the swing axis C when viewed from the straight torsion beam 88b. The bent torsion beams 90b, 94b, 98b, 102b, and 106b and the corresponding bent torsion beams 92b, 96b, 100b, 104b, and 108b are symmetrical with respect to the oscillation axis C when the MEMS device 82 is viewed from above. It is arranged in the position.

  The bending torsion beams 90a, 90b, 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, 106a, 106b, 108a, 108b are all supported by the support frame 4. And a support-side connecting portion extending linearly along the swing axis C, and a support that bends substantially perpendicularly from the support-side connection portion toward the swing shaft C and then gently curves in the direction along the swing axis C. The side curved portion, the swing side connecting portion extending linearly from the swing plate 6 along the swing axis C, and the swing after being bent substantially perpendicularly from the swing side connection portion toward the swing axis C A swing side bending portion that gently curves in a direction along the axis C and a central straight portion that extends along the swing axis C and connects the support side bending portion and the swing side bending portion. Bending torsion beams 90a, 90b, 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, 106a, 106b, 108a, 108b The side curved portion functions as a stress relaxation portion that relaxes the tensile stress generated during torsional deformation. With such a configuration, the torsional beams 90a, 90b, 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b are maintained while keeping the torsional rigidity of the torsional beams 84a, 84b constant. , 102a, 102b, 104a, 104b, 106a, 106b, 108a, 108b can be improved. A highly reliable torsion beam group 84a, 84b that does not break even when driven greatly can be realized.

  In the MEMS device 82 of the present embodiment, the bent torsion beams 90a, 90b, 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, 106a, 106b, 108a, In 108b, the support-side connecting portion extends linearly from the support frame 4 along the swing axis C, and the support-side curved portion is bent at a substantially right angle from the support-side connecting portion toward the swing axis C. . With such a configuration, the bent torsion beams 90a, 90b, 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, 106a, 106b, 108a, It is possible to lengthen the portion of the support-side curved portion that extends perpendicularly to the swing axis C without increasing the length of the 108b along the swing axis C. The longer this part is, the easier it is to deform in the direction along the swing axis C, so the tensile stress accompanying torsional deformation can be relaxed. As a result, since the MEMS device 82 having many torsion beams can be realized, the length of the beams can be shortened while maintaining the rigidity of the torsion beam groups 84a and 84b. As a result, the chip area can be reduced. In the MEMS device 82 of the present embodiment, the bent torsion beams 90a, 90b, 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, 106a, 106b, In 108a and 108b, the support-side curved portion is bent at a substantially right angle from the support-side connecting portion toward the swing axis C, and then gently bent in the direction along the swing shaft C. By setting it as such a structure, the stress concentration in a support side curved part can be relieved.

  In the MEMS device 82 of the present embodiment, the bent torsion beams 90a, 90b, 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, 106a, 106b, 108a, In 108b, the oscillating side connecting portion extends linearly from the oscillating plate 6 along the oscillating axis C, and the oscillating side curved portion is substantially perpendicular to the oscillating axis C from the oscillating side connecting portion. It is bent. With such a configuration, the bent torsion beams 90a, 90b, 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, 106a, 106b, 108a, The portion of the oscillating side bending portion extending perpendicularly to the oscillating axis C can be increased without increasing the length in the direction along the oscillating axis C of 108b. The longer this part is, the easier it is to deform in the direction along the swing axis C, so the tensile stress accompanying torsional deformation can be relaxed. As a result, since the MEMS device 82 having many torsion beams can be realized, it is possible to reduce the size of the portion other than the swing plate 6 while maintaining the rigidity of the torsion beam groups 84a and 84b. In the MEMS device 82 of the present embodiment, the bent torsion beams 90a, 90b, 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, 106a, 106b, In 108a and 108b, the oscillating side bending portion is bent at a substantially right angle from the oscillating side connecting portion toward the oscillating axis C, and then gently curved in the direction along the oscillating axis C. By adopting such a configuration, stress concentration in the rocking side bending portion can be relaxed.

  In the bent torsion beams 90a, 90b, 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, 106a, 106b, 108a, 108b, It is desirable to form the moving side connection portion wide. The wider the support side connection portion and the swing side connection portion, the higher the spring constant than the support side bending portion and the swing side bending portion. Therefore, the support side connection portion and the swing side connection portion are less likely to be deformed. . Since the deformation amount at the support side connection portion and the swing side connection portion is reduced, the stress acting on the support side connection portion and the swing side connection portion can be reduced. In the above-described embodiment, the straight torsion beams 86a, 86b, 88a, and 88b are connected to the support frame 4 and the connection portion to the swing plate 6 are formed with stress relieving fillets. Bending and twisting beams 90a, 90b, 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, 106a, 106b, 108a, 108b and swinging The side connection part is not formed with a fillet for stress relaxation. This is due to stress relaxation in the bent torsion beams 90a, 90b, 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, 106a, 106b, 108a, 108b. This is because the support-side bending portion and the swing-side bending portion that function as the portions are formed, so that a large stress concentration does not occur in the support-side connection portion and the swing-side connection portion. With such a configuration, the space between the adjacent bending torsion beams can be narrowed, and the bending torsion beams 90a, 90b, and 92a that can be disposed in the limited space of the support frame 4 and the swing plate 6 are provided. , 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, 106a, 106b, 108a, 108b can be increased. Unlike the above, the bent torsion beams 90a, 90b, 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, 106a, 106b, 108a, 108b You may form the fillet for relieving stress concentration also in a support side connection part and a rocking | swiveling side connection part.

  The torsional deformation that occurs when the swing plate 6 swings is caused by the torsion beams (for example, straight torsion beams 86a, 86b, 88a, 88b and bent torsion beams 90a, 90b, 92a) disposed at positions close to the swing axis C. , 92b), the torsion beam (for example, the bent torsion beams 102a, 102b, 104a, 104b, 106a, 106b, 108a, 108b) disposed at a position far from the swing axis C becomes larger. Correspondingly, in the MEMS device 82 of the present embodiment, the torsion beams (for example, the bent torsion beams 102a, 102b, 104a, 104b, 106a, 106b, 108a, 108b) arranged at positions away from the swing axis C are provided. ) Is longer than the torsion beams (for example, straight torsion beams 86a, 86b, 88a, and 88b and bent torsion beams 90a, 90b, 92a, and 92b) disposed near the swing axis C. Is formed. With this configuration, the spring constant in the direction along the swing axis C of the support-side bending portion and the swing-side bending portion can be reduced. Even when the amount of deformation in the direction along the swing axis C increases during swinging, the spring constant of the support-side bending portion and the swinging-side bending portion becomes small, so that it occurs in the support-side bending portion and the swinging-side bending portion. Stress to be reduced. As a result, it is possible to prevent a large tensile stress from acting on the torsion beam disposed at a position away from the swing axis C.

  When the drive frequency of the electromagnets 14a and 14b is matched with the resonance frequency of the swing plate 6, the swing plate 6 can be operated largely with a small drive power. In order to operate the oscillating plate 6 at high speed in such resonance driving, it is necessary to increase the driving frequency of the electromagnets 14a and 14b and to increase the resonance frequency of the oscillating plate 6 accordingly. Moreover, in order to ensure the durability of the MEMS device 82, it is necessary to ensure the strength of the torsion beam groups 84a and 84b. In addition, in order to improve the ratio of the effective reflection area in the MEMS device 82, it is preferable to shorten the lengths of the torsion beam groups 84a and 84b as much as possible.

  In the MEMS device 82 of the present embodiment, one torsion beam group 84a is constituted by twelve torsion beams, and the other torsion beam group 84b is constituted by twelve torsion beams. The length of the torsion beam groups 84a and 84b can be shortened while ensuring the resonance frequency 6 and the strength of the torsion beam groups 84a and 84b. Hereinafter, the relationship between the number of torsion beams in the torsion beam groups 84a and 84b and the lengths of the torsion beam groups 84a and 84b will be described.

  As shown in FIG. 10, a configuration is considered in which one end of the swing plate P is supported by a single torsion beam BR and the other end is supported by a single torsion beam BL. In this case, the resonance frequency fr of the oscillating plate P is given by the following equation.

  Here, K is the torsional rigidity (only on one side) of the torsion beams BR and BL, and J is the moment of inertia of the swing plate P.

  The torsional rigidity K of the torsion beams BR and BL is given by the following equation.

  Here, l is the length of the torsion beams BR and BL, a is the length of the long side of the cross section of the torsion beams BR and BL, and b is the length of the short side of the cross section of the torsion beams BR and BL. Yes, G is the transverse elastic modulus of the torsion beams BR and BL. In the following description, it is assumed that the cross-section height tb of the torsion beams BR and BL is longer than the cross-section width wb. That is, in this description, tb corresponds to the length a of the long side of the cross section of the torsion beams BR and BL, and wb corresponds to the length b of the short side of the cross section of the torsion beams BR and BL.

  The moment of inertia J of the swing plate P is given by the following equation.

  Here, ρ is the mass density of the swing plate P, W is the width of the swing plate P, L is the length of the swing plate P, and T is the thickness of the swing plate P.

  When the oscillating plate 6 is resonantly driven, it is necessary to make the resonance frequency fr of the oscillating plate 6 coincide with a predetermined frequency.

  Regarding the strength of the torsion beams BR and BL, the shear stress τ acting on the torsion beams BR and BL is given by the following equation.

  Here, θ is the maximum inclination angle of the swing plate P.

  In order to ensure the strength of the torsion beams BR and BL, the shear stress τ acting on the torsion beams BR and BL must be set to the allowable shear stress τmax or less.

  Therefore, the minimum value of l that satisfies the condition of Expression (7) after satisfying the conditions of Expressions (1) to (4) is the minimum length of the torsion beams BR and BL that can be realized.

  For example, the resonance frequency fr of the swing plate P is 3 kHz, the mass density ρ of the swing plate P is 2330 kg / m3, the width W of the swing plate P is 5 mm, and the length L of the swing plate P is 5 mm. The thickness T of the swing plate P is 0.5 mm, the maximum inclination angle θ of the swing plate P is 15 °, the transverse elastic modulus G of the torsion beams BR and BL is 64 GPa, and the allowable shear of the torsion beams BR and BL When the stress τmax is 1 GPa and the long side length “a” (cross-sectional height tb) of the torsion beams BR and BL is 0.5 mm, the torsion beams BR and BL have the minimum length. This is when the short side length b (cross-sectional width wb) of the cross section of the beams BR and BL is 0.142 mm, and the length of the torsion beams BR and BL at that time is 2.3 mm. Accordingly, in the configuration shown in FIG. 10 where the swing plate P is supported from both sides by the single torsion beam BR, BL, the length of the torsion beam BR, BL cannot be made shorter than 2.3 mm.

  Next, as shown in FIG. 11, one end portion of the swing plate P is supported by a torsion beam group BRn composed of n torsion beams, and the other end portion is a torsion beam group composed of n torsion beams. Consider a configuration supported by BLn. In this case, the resonance frequency fr of the oscillating plate P is given by the following equation.

  Here, Kall is the torsional rigidity (only on one side) of the torsion beam groups BRn and BLn, and J is the moment of inertia of the swing plate P.

  The torsional rigidity Kall of the torsion beam groups BRn and BLn is calculated by the following equation.

  Here, l is the length of the torsion beam groups BRn and BLn, a is the length of the long side of the cross section of each torsion beam group BRn and BLn, and b is the length of the torsion beam groups BRn and BLn. It is the length of the short side of the cross section of each torsion beam, and G is the transverse elastic modulus of the torsion beam groups BRn and BLn. In the following description, it is assumed that the height tb of the cross section of each torsion beam of the torsion beam groups BRn and BLn is longer than the width wb of the cross section. That is, in this description, tb is the length a of the long side of each torsion beam cross section of the torsion beam groups BRn and BLn, and wb is the short length of the cross section of each torsion beam of the torsion beam groups BRn and BLn. It corresponds to the side length b.

  The moment of inertia J of the swing plate P is given by the above mathematical formula (4).

  When the oscillating plate 6 is resonantly driven, it is necessary to make the resonance frequency fr of the oscillating plate 6 coincide with a predetermined frequency.

  Regarding the strength of the torsion beam groups BRn and BLn, the shear stress τ acting on the individual torsion beams of the torsion beam groups BRn and BLn is given by the following equation.

  Here, θ is the maximum inclination angle of the swing plate P.

  In order to ensure the strength of the torsion beam groups BRn and BLn, the shear stress τ acting on the individual torsion beams of the torsion beam groups BRn and BLn must be equal to or less than the allowable shear stress τmax.

  Therefore, after satisfying the conditions of the above formulas (4), (8) to (10), the minimum value of l satisfying the condition of the formula (13) is the minimum of the realizable torsion beam groups BRn, BLn. It becomes length.

  For example, the resonance frequency fr of the swing plate P is 3 kHz, the mass density ρ of the swing plate P is 2330 kg / m3, the width W of the swing plate P is 5 mm, and the length L of the swing plate P is 5 mm. The thickness T of the oscillating plate P is 0.5 mm, the maximum inclination angle θ of the oscillating plate P is 15 °, the transverse elastic modulus G of the torsion beam groups BRn, BLn is 64 GPa, and the torsion beam groups BRn, BLn The allowable shear stress τmax is set to 1 GPa, the number n of torsion beams of the torsion beam groups BRn and BLn is set to 5, and the length a of each torsion beam of the torsion beam groups BRn and BLn (the height tb of the cross section) is set. In the case of 0.5 mm, if the short side length b (cross-sectional width wb) of each torsion beam group of the torsion beam groups BRn and BLn is 0.06 mm, the length of the torsion beam groups BRn and BLn. Can be 1.0 mm. Therefore, as shown in FIG. 11, by adopting a configuration in which the swing plate P is supported from both sides by a torsion beam group BRn, BLn composed of a plurality of torsion beams, the torsion beam group BRn is compared with the configuration shown in FIG. , BLn can be shortened.

  In the above calculation example, the case where the number n of torsion beams in the torsion beam groups BRn and BLn is 5 has been described. However, the number n of torsion beams in the torsion beam groups BRn and BLn satisfies the following relationship. That's fine.

  When the number n of torsion beams satisfies the condition of the above formula (14), the torsion beam group is secured while ensuring the necessary resonance frequency of the swing plate P and the strength of the torsion beam groups BRn and BLn. The lengths of BRn and BLn can be shortened.

  In the MEMS device 82 of the present embodiment shown in FIG. 9, in addition to the gap necessary for the movable part to move in the vicinity of the location where the movable range of the movable part is large (the end of the swing plate 6 in the Y-axis direction). The air gap was wide enough to allow air to move. By taking a large gap as described above, the amount of compressed air is reduced. Thereby, the speed of the air injected from the gap can be reduced. As a result, noise can be reduced. Furthermore, the area of the support frame 4 can be increased by shortening the torsion beam length. Thereby, since the intensity | strength of the support frame 4 can be raised, the Q value of the MEMS apparatus 82 can be made high. As a result, the driving power of the MEMS device 82 can be reduced.

Example 9
FIG. 12 shows the MEMS device 112 of this embodiment. The MEMS device 112 has the same configuration as the MEMS device 82 of the eighth embodiment shown in FIG. Hereinafter, only the difference of the MEMS device 112 from the MEMS device 82 of the eighth embodiment will be described.

  In the MEMS device 112 of this embodiment, the bent torsion beams 90a, 90b, 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, 106a, 106b, 108a, The support side connection part 108b is integrated. In the MEMS device 112 of the present embodiment, the bent torsion beams 90a, 90b, 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, 106a, 106b, The swing side connecting portions 108a and 108b are integrated. Vent holes 114a, 114b, 116a, 116b (which is an example of a third vent hole) are formed in the integrated swing side connecting portion. The width of the vent holes 114a, 114b, 116a, 116b in the X-axis direction is wider as it is farther from the swing axis C (that is, closer to the end in the Y-axis direction of the swing plate 6), and closer to the swing axis C. (Ie, the farther from the end of the swing plate 6 in the Y-axis direction), the narrower the shape.

  According to the MEMS device 112 of the present embodiment, the air holes 114 a, 114 b, 116 a, and 116 b are formed in the swing side connection portion, so that air is compressed between the swing side connection portion and the support frame 4. Generation of noise can be suppressed. Further, since the air holes 114 a, 114 b, 116 a, and 116 b are formed in the swing side connection portion, air pushed by the swing plate 6 escapes, so that air is moved between the swing plate 6 and the support frame 4. It can also be suppressed that noise is generated by being compressed. Further, since the vent holes 114a, 114b, 116a, 116b are formed in the swing side connecting portion, the inertia moment of the swing plate 6 and the torsion beam groups 84a, 84b is reduced, so that a desired resonance frequency is obtained. The spring constants of the torsion beam groups 84a and 84b for realizing the above can be reduced, and the torsion beam groups 84a and 84b can be shortened.

  In the MEMS device 112 of the present embodiment, the width of the vent holes 114a, 114b, 116a, 116b in the X-axis direction is wider at a position farther from the swing axis C that swings at high speed and large amplitude, and swings at low speed and small amplitude. The closer to the moving swing axis C, the narrower the shape. With such a configuration, the bent torsion beams 90a, 90b, 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, 106a, 106b, 108a, Generation of noise can be suppressed while maintaining the strength and rigidity of 108b. Further, since the moment of inertia of the swing plate 6 and the torsion beam groups 84a and 84b is reduced, the spring constant of the torsion beam groups 84a and 84b for realizing a desired resonance frequency can be reduced, and the torsion beam The groups 84a and 84b can be shortened. By shortening the torsion beam length, the area of the support frame 4 can be increased. Thereby, since the intensity | strength of the support frame 4 can be raised, the Q value of the MEMS apparatus 112 can be made high. As a result, the driving power of the MEMS device 112 can be reduced.

(Example 10)
FIG. 13 shows the MEMS device 122 of this embodiment. The MEMS device 122 has the same configuration as the MEMS device 82 of the eighth embodiment shown in FIG. Below, only the difference between the MEMS device 122 and the MEMS device 82 of the eighth embodiment will be described.

  In the MEMS device 122 of the present embodiment, the support frame 4 extends toward the central straight portion of the bent torsion beams 106a, 106b, 108a, 108b, and between the support frame 4 and the bent torsion beams 106a, 106b, 108a, 108b. Of the torsion beams 86a, 86b, 88a, 88b and the bent torsion beams 90a, 90b, 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, The distance between the adjacent beams 106a, 106b, 108a, 108b is approximately the same. When beams are produced by a processing method such as Deep Reactive Ion Etching (DRIE), the beam width of each beam changes due to the microloading effect if the distance between the beams is different. In the case of the structure of the ninth embodiment, since the space outside the beam farthest from the swing axis is wide, the microloading effect occurs in the beam farthest from the swing shaft. Since the processing accuracy of the beam decreases, the torsional rigidity of the beam group changes from the design value, and the resonance frequency deviates from the design value. By making all the beam intervals substantially constant as in this embodiment, the occurrence of the microloading effect is suppressed, and the straight torsion beams 86a, 86b, 88a, 88b and the bent torsion beams 90a, 90b, 92a, 92b, 94a are suppressed. 94b, 96a, 96b, 98a, 98b, 100a, 100b, 102a, 102b, 104a, 104b, 106a, 106b, 108a, 108b can be formed with high accuracy. As a result, the torsional rigidity of the beam group can be produced according to the set value, so that the designed resonance frequency can be realized. The MEMS device 122 of the present embodiment is similar to the MEMS device 82 of the eighth embodiment in that the distance between the side surface of the end portion in the Y-axis direction of the swing plate 6 and the side surface of the support frame 4 is a bent torsion beam. The distance between the side surfaces in the Y-axis direction of 106a, 106b, 108a, and 108b and the side surface of the support frame 4 is larger. By adopting such a configuration, it is possible to suppress the generation of noise between the side surface of the end portion in the Y-axis direction of the swing plate 6 and the side surface of the support frame 4 while ensuring the rigidity and strength of the support frame 4. can do.

(Example 11)
FIG. 14 shows a MEMS device 132 of this embodiment. The MEMS device 132 has the same configuration as the MEMS device 82 of the eighth embodiment. Hereinafter, only the difference of the MEMS device 132 from the MEMS device 82 of the eighth embodiment will be described.

  In the MEMS device 132 of this embodiment, the torsion beam group 84a includes two straight torsion beams 86a and 88a and six bent torsion beams 90a, 92a, 94a, 96a, 98a, and 100a. The group 84b includes two straight torsion beams 86b and 88b and six bent torsion beams 90b, 92b, 94b, 96b, 98b, and 100b. In the MEMS device 132 of the present embodiment, the swing side connecting portions of the bent torsion beams 98 a, 98 b, 100 a, and 100 b arranged on the outermost side are closer to the swing axis C than the end portions of the swing plate 6 in the Y direction. It is arranged at a close position. In the MEMS device 132 of the present embodiment, the spacing between the support frame 4 and the central straight portions of the bent torsion beams 98a, 98b, 100a, and 100b is the straight torsion beams 86a, 86b, 88a, and 88b and the bent torsion beams 90a and 90b. , 92a, 92b, 94a, 94b, 96a, 96b, 98a, 98b, 100a, 100b, the distance between the central straight portions of adjacent beams is substantially equal. The distance between the support frame 4 and the support side connecting portions of the bent torsion beams 98a, 98b, 100a, and 100b is substantially equal to the distance between the support frame 4 and the central straight portion of the bent torsion beams 98a, 98b, 100a, and 100b. . The distance between the support frame 4 and the swing side connecting portions of the bent torsion beams 98a, 98b, 100a, 100b is larger than the distance between the support frame 4 and the support side connecting portions of the bent torsion beams 98a, 98b, 100a, 100b. Is also wide. The distance between the swing plate 6 and the support frame 4 is wider than the distance between the support frame 4 and the swing side connecting portions of the bent torsion beams 98a, 98b, 100a, 100b.

  In the MEMS device 132 of the present embodiment, the distance between the support frame 4 and the swing side connecting portions of the bent torsion beams 98a, 98b, 100a, 100b is such that the support frame 4 and the bent torsion beams 98a, 98b, 100a, 100b It is formed wider than the interval between the support side connection portions. By adopting such a configuration, it is possible to suppress the generation of noise between the support frame 4 and the swing side connecting portions of the bent torsion beams 98a, 98b, 100a, and 100b.

Example 12
FIG. 15 shows the MEMS device 142 of this embodiment. The MEMS device 142 includes an oscillating plate 6 (an example of a second movable part of claim 14 and an example of a movable part of claim 16), a mirror 8, a permanent magnet 12, and a first torsion beam group. 144a, 144b (an example of the second connecting part of claim 14, and an example of the connecting part of claim 16) and a first support frame 146 (an example of the second supporting part of claim 14, And a second torsion beam group 148a, 148b (an example of a connection part of claim 14, and an example of a third connection part of claim 16), and a second support. A frame 150 (an example of a support part of claim 14 and an example of a third support part of claim 16), first electromagnets 152a and 152b, and second electromagnets 154a and 154b are provided.

  The configuration of the swing plate 6, the mirror 8, the permanent magnet 12, the first torsion beam groups 144a and 144b, the first support frame 146, and the first electromagnets 152a and 152b is the same as that of the MEMS device 122 of the tenth embodiment shown in FIG. The swing plate 6, the mirror 8, the permanent magnet 12, the torsion beam groups 84a and 84b, the support frame 4, and the electromagnets 14a and 14b are not described in detail.

  The second support frame 150 surrounds the rocking plate 6, the first torsion beam groups 144a and 144b, the first support frame 146, and the second torsion beam groups 148a and 148b when the MEMS device 142 is viewed from above. It is formed in a surrounding shape.

  The first support frame 146 is supported by the second support frame 150 via the second torsion beam groups 148a and 148b so as to be swingable around the swing axis C2 along the Y-axis direction. The configuration of the second torsion beam groups 148a and 148b connecting the first support frame 146 and the second support frame 150 is the same except that the direction of the swing axis C2 is different from the direction of the swing axis C. Since it is the same as that of the structure of the 1st torsion beam group 144a, 144b which connects between the moving plate 6 and the 1st support frame 148, detailed description is abbreviate | omitted.

  The second electromagnets 154a and 154b are formed by winding a coil around the iron core. The second electromagnets 154a and 154b are arranged so as to sandwich the permanent magnet 12 of the swing plate 6 from the outside of the second support frame 150 in the X-axis direction.

  Regarding the magnitude relationship between the distance in the X direction between the second support frame 150 and the first support frame 146 and the distance in the X direction between the second support frame 150 and the second torsion beam groups 148a and 148b, This is the same as the magnitude relationship between the distance in the Y direction between the support frame 146 and the swing plate 6 and the distance in the Y direction between the first support frame 146 and the first torsion beam groups 144a and 144b.

  The MEMS device 142 of the present embodiment uses the magnetic force acting between the permanent magnet 12 and the first electromagnets 152a and 152b to move the swing plate 6 around the swing axis C with respect to the first support frame 146, that is, It can be swung around the X axis. Further, the MEMS device 142 according to the present embodiment uses the magnetic force acting between the permanent magnet 12 and the second electromagnets 154a and 154b to move the swing plate 6 and the first support frame 146 to the second support frame 150. It can be swung around the swing axis C2, that is, around the Y axis. The MEMS device 142 can be operated as a biaxial optical deflection device.

  In the MEMS device 142 of the present embodiment, the swing plate 6 and the first support frame 146 are connected by the first torsion beam groups 144a and 144b including a plurality of torsion beams. With this configuration, the size of the first support frame 146 in the X-axis direction can be reduced. By reducing the size of the first support frame 146 in the X-axis direction, the moment of inertia around the Y-axis of the first support frame 146, that is, the moment of inertia around the swing axis C2 can be reduced, and the second torsion beam Even if the spring constants of the groups 148a and 148b are reduced, a desired resonance frequency can be realized. Accordingly, the second torsion beam groups 148a and 148b can be shortened, and the MEMS device 142 can be downsized. Further, by reducing the size of the first support frame 146 in the X-axis direction, the swing of the end portion of the first support frame 146 in the X-axis direction with respect to the second support frame 150 can be performed at a low speed and with a small amplitude. In addition, it is possible to suppress the generation of loud noise due to strong compression of air between the first support frame 146 and the second support frame 150. In particular, the swing of the end of the first support frame 146 in the X-axis direction with respect to the second support frame 150 is faster than the swing of the end of the swing plate 6 in the Y-axis direction with respect to the first support frame 146. In addition, the amplitude is large and the generated noise is large. As described above, by suppressing the generation of noise between the first support frame 146 and the second support frame 150, the noise generated when the MEMS device 142 is operating can be significantly suppressed.

  Further, in the MEMS device 142 of the present embodiment, the first support frame 146 and the second support frame 150 are connected by the second torsion beam groups 148a and 148b composed of a plurality of torsion beams. By setting it as such a structure, the area of the 2nd support frame 150 can be enlarged. Thereby, since the strength of the second support frame 150 and the fixing strength of the MEMS device 142 can be improved, the Q value of the MEMS device 142 can be increased. As a result, the driving power of the MEMS device 142 can be reduced.

(Example 13)
FIG. 16 shows the MEMS device 162 of the present embodiment. The MEMS device 162 has the same configuration as the MEMS device 142 of the twelfth embodiment shown in FIG. Hereinafter, only the difference of the MEMS device 162 from the MEMS device 142 of the twelfth embodiment will be described.

  In the MEMS device 162 of the present embodiment, the first torsion beam groups 144a and 144b are respectively formed of two straight torsion beams in the same manner as the torsion beam groups 84a and 84b of the MEMS device 132 of the eleventh embodiment shown in FIG. , 6 bending torsion beams are provided. Regarding the relationship among the swing plate 6, the first torsion beam groups 144a and 144b, and the first support frame 146 in the MEMS device 162 of this embodiment, the swing plate 6 in the MEMS device 132 of Embodiment 11 shown in FIG. The torsion beam groups 84 a and 84 b and the support frame 4 are the same.

  In the MEMS device 162 of the present embodiment, the second torsion beam groups 148a and 148b are respectively formed of two straight torsion beams in the same manner as the torsion beam groups 84a and 84b of the MEMS device 132 of the embodiment 11 shown in FIG. , 6 bending torsion beams are provided. Regarding the relationship between the first support frame 146, the second torsion beam groups 148a and 148b, and the second support frame 150 in the MEMS device 162 of the present embodiment, the direction of the swing axis C2 is different from the direction of the swing axis C. Except for this point, the relationship between the swing plate 6, the torsion beam groups 84a and 84b, and the support frame 4 in the MEMS device 132 according to the eleventh embodiment shown in FIG. 14 is the same.

(Example 14)
FIG. 17 shows a MEMS device 172 of this embodiment. The MEMS device 172 has the same configuration as the MEMS device 142 of Example 12 shown in FIG. Hereinafter, only the difference of the MEMS device 172 from the MEMS device 142 of the twelfth embodiment will be described.

  In the MEMS device 172 of this embodiment, when the MEMS device 172 is viewed from above, the side surface of the first support frame 146 that faces the swing side bending portion of the first torsion beam groups 144a and 144b is the swing shaft. It is formed in a shape that is further away from the swing plate 6 as the position is further away from C. For this reason, the distance between the rocking side bent portions of the first torsion beam groups 144a and 144b and the side surface of the first support frame 146 increases as the position becomes farther from the rocking axis C. With such a configuration, noise is generated between the swing-side bent portions of the first torsion beam groups 144a and 144b and the first support frame 146 while ensuring the strength and rigidity of the first support frame 146. This can be suppressed.

  In the MEMS device 172 of the present embodiment, when the MEMS device 172 is viewed from above, the side surface of the second support frame 150 that faces the swing side bending portion of the second torsion beam group 148a, 148b is the swing shaft. It is formed in the shape which leaves | separates from the 1st support frame 146, so that it becomes a position far from C2. For this reason, the distance between the rocking side bent portions of the second torsion beam groups 148a and 148b and the side surface of the second support frame 150 increases as the position becomes farther from the rocking axis C2. With such a configuration, noise is generated between the swinging bent portions of the second torsion beam groups 148a and 148b and the second support frame 150 while ensuring the strength and rigidity of the second support frame 150. This can be suppressed.

(Example 15)
FIG. 18 shows a MEMS device 182 of this embodiment. The MEMS device 182 has the same configuration as the MEMS device 162 of Example 13 shown in FIG. Hereinafter, only the difference of the MEMS device 182 from the MEMS device 162 of the thirteenth embodiment will be described.

  In the MEMS device 182 of the present embodiment, when the MEMS device 182 is viewed from above, the side surface of the first support frame 146 that faces the swing side bending portion of the first torsion beam groups 144a and 144b is the swing shaft. It is formed in a shape that is further away from the swinging bent portion of the first torsion beam group 144a, 144b as it is farther from C. For this reason, the distance between the rocking side bent portions of the first torsion beam groups 144a and 144b and the side surface of the first support frame 146 increases as the position becomes farther from the rocking axis C. With such a configuration, noise is generated between the swing-side bent portions of the first torsion beam groups 144a and 144b and the first support frame 146 while ensuring the strength and rigidity of the first support frame 146. This can be suppressed.

  In the MEMS device 182 of the present embodiment, the side surface of the first support frame 146 facing the end portion in the X direction of the swing plate 6 is separated from the swing axis C when the MEMS device 182 is viewed from above. It is formed in a shape that moves away from the swing plate 6 as the position is reached. For this reason, the distance between the end portion in the X direction of the swing plate 6 and the side surface of the first support frame 146 increases as the position becomes farther from the swing shaft C. With such a configuration, it is possible to suppress the generation of noise between the X-direction end of the swing plate 6 and the first support frame 146 while ensuring the strength and rigidity of the first support frame 146. be able to.

  In the MEMS device 182 of this embodiment, when the MEMS device 182 is viewed from above, the side surface of the second support frame 150 that faces the swing side bending portion of the second torsion beam groups 148a and 148b is the swing shaft. As the position is farther from C2, the second torsion beam groups 148a and 148b are formed so as to be farther from the swinging bent portion. For this reason, the distance between the rocking side bent portions of the second torsion beam groups 148a and 148b and the side surface of the second support frame 150 increases as the position becomes farther from the rocking axis C2. With such a configuration, noise is generated between the swinging bent portions of the second torsion beam groups 148a and 148b and the second support frame 150 while ensuring the strength and rigidity of the second support frame 150. This can be suppressed.

  In the MEMS device 182 of the present embodiment, when the MEMS device 182 is viewed from above, the side surface of the second support frame 150 facing the end portion in the Y direction of the first support frame 146 is separated from the swing axis C2. It is formed in the shape which leaves | separates from the 1st support frame 146, so that it becomes a position. For this reason, the distance between the end portion in the Y direction of the first support frame 146 and the side surface of the second support frame 150 becomes larger as the position is farther from the swing axis C2. By adopting such a configuration, it is possible to suppress the generation of noise between the end portion of the first support frame 146 in the Y direction and the second support frame 150 while ensuring the strength and rigidity of the second support frame 150. can do.

(Example 16)
FIG. 19 shows a MEMS device 192 of the present embodiment. The MEMS device 192 includes an oscillating plate 6 (an example of a second movable part of claim 14 and an example of a movable part of claim 16), a mirror 8, a permanent magnet 12, and a first torsion beam 194a. 194b (which is an example of the second connecting portion of claim 14 and also an example of the connecting portion of claim 16) and a first support frame 196 (which is an example of the second supporting portion of claim 14, 16 and a second torsion beam 198a, 198b (an example of a connection part of claim 14 and an example of a third connection part of claim 16), and a second support frame 200. (An example of a support part of claim 14 and an example of a third support part of claim 16), first electromagnets 152a and 152b, and second electromagnets 154a and 154b.

  The swing plate 6, the mirror 8, the permanent magnet 12, the first electromagnets 152a and 152b, and the second electromagnets 154a and 154b in the MEMS device 192 of the present embodiment are the same as the MEMS device 142 of the twelfth embodiment shown in FIG. It is.

  The first support frame 196 is formed in a rectangular frame shape surrounding the swing plate 6 and the first torsion beams 194a and 194b when the MEMS device 192 is viewed from above. The swing plate 6 is supported by the first support frame 196 via the first torsion beams 194a and 194b so as to be swingable around the swing axis C along the X-axis direction. The first torsion beams 194a and 194b are linear members extending along the X-axis direction. The first torsion beams 194a and 194b are formed in a shape with high rigidity against bending and low rigidity against torsion. The first torsion beams 194a and 194b support the swing plate 6 from both sides in the X-axis direction (that is, from both sides in the direction along the swing axis C).

  A vent hole 202 (which is an example of a first vent hole) is formed at the end of the first support frame 196 in the X-axis direction. Vent holes 204 (an example of first vent holes) are formed at both ends of the first support frame 196 in the Y-axis direction.

  When the MEMS device 192 is viewed in plan view from above, the second support frame 200 is arranged around the swing plate 6, the first torsion beams 194a and 194b, the first support frame 196, and the second torsion beams 198a and 198b. Is formed in a rectangular frame shape. The first support frame 196 is supported by the second support frame 200 via the second torsion beams 198a and 198b so as to be swingable around the swing axis C2 along the Y-axis direction. The second torsion beams 198a and 198b are linear members extending along the Y-axis direction. The second torsion beams 198a and 198b are formed in a shape with high rigidity against bending and low rigidity against torsion. The second torsion beams 198a and 198b support the first support frame 196 from both sides in the Y-axis direction (that is, from both sides in the direction along the swing axis C2).

  The MEMS device 192 of the present embodiment uses the magnetic force acting between the permanent magnet 12 and the first electromagnets 152a and 152b to move the swing plate 6 around the swing axis C with respect to the first support frame 196, that is, It can be swung around the X axis. In addition, the MEMS device 192 of this embodiment uses the magnetic force acting between the permanent magnet 12 and the second electromagnets 154a and 154b to move the swing plate 6 and the first support frame 196 to the second support frame 200. It can be swung around the swing axis C2, that is, around the Y axis. The MEMS device 192 can be operated as a biaxial optical deflection device.

  In the MEMS device 192 of the present embodiment, a vent hole 202 is formed at the end of the first support frame 196 in the X direction. Thereby, it is possible to suppress the generation of noise between the end portion of the first support frame 196 in the X direction and the second support frame 200. Further, since the moment of inertia around the Y axis of the first support frame 196 is reduced, the spring constant of the second torsion beams 198a and 198b for realizing a desired resonance frequency can be reduced, and the second torsion beam 198a. , 198b can be shortened. For this reason, the area of the 2nd support frame 200 can be enlarged compared with the conventional MEMS apparatus with the same chip area. Accordingly, the strength of the second support frame 200 and the fixing strength of the MEMS device 192 can be improved, so that the Q value of the MEMS device 192 can be increased. As a result, the driving power of the MEMS device 192 can be reduced.

  In the MEMS device 192 of the present embodiment, a vent hole 204 is formed at the end of the first support frame 196 in the Y direction. Thereby, it is possible to suppress the generation of noise between the end portion of the first support frame 196 in the Y direction and the second support frame 200. Further, since the moment of inertia around the Y axis of the first support frame 196 is reduced, the spring constant of the second torsion beams 198a and 198b for realizing a desired resonance frequency can be reduced, and the second torsion beam 198a. , 198b can be shortened. For this reason, the area of the 2nd support frame 200 can be enlarged compared with the conventional MEMS apparatus with the same chip area. Accordingly, the strength of the second support frame 200 and the fixing strength of the MEMS device 192 can be improved, so that the Q value of the MEMS device 192 can be increased. As a result, the driving power of the MEMS device 192 can be reduced.

(Example 17)
FIG. 20 shows the MEMS device 212 of this embodiment. The MEMS device 212 has the same configuration as the MEMS device 182 of the fifteenth embodiment shown in FIG. Hereinafter, only the difference of the MEMS device 212 from the MEMS device 182 of the fifteenth embodiment will be described.

  In the MEMS device 212 of the present embodiment, when the MEMS device 212 is viewed from above in the vicinity of the end portion in the X direction of the first support frame 146, the Y of the first support frame 146 increases as the distance from the swing axis C2 increases. The first support frame 146 is formed so that the width in the direction becomes narrow. For this reason, the distance in the Y direction between the side surface of the first support frame 146 and the side surface of the second support frame 150 increases as the position becomes farther from the swing axis C2. With such a configuration, it is possible to suppress the generation of noise between the first support frame 146 and the second support frame 150 while ensuring the strength and rigidity of the second support frame 150. Further, since the moment of inertia around the Y axis of the first support frame 146 is reduced, the spring constants of the second torsion beam groups 148a and 148b for realizing a desired resonance frequency can be reduced, and the second torsion beam can be reduced. The groups 148a and 148b can be shortened. For this reason, the area of the second support frame 150 can be increased as compared with a conventional MEMS device having the same chip area. Thereby, since the strength of the second support frame 150 and the fixing strength of the MEMS device 212 can be improved, the Q value of the MEMS device 212 can be increased. As a result, the driving power of the MEMS device 212 can be reduced.

(Example 18)
FIG. 21 shows a MEMS device 222 of this embodiment. The MEMS device 222 has the same configuration as the MEMS device 142 of the twelfth embodiment shown in FIG. Hereinafter, only the differences of the MEMS device 222 from the MEMS device 142 of the twelfth embodiment will be described.

  In the MEMS device 222 of the present embodiment, the rocking side connection portions of the first torsion beam groups 144a and 144b are integrated, and the holes 224a and 224b (third) are integrated into the integrated rocking side connection portion. This is an example of the vent hole. The width of the vent holes 224a and 224b in the X direction is formed so as to be wider as it is farther from the swing axis C and narrower as it is closer to the swing axis C. The side surface of the first support frame 146 that faces the swing side bending portion of the first torsion beam group 144a, 144b is further away from the swing side bending portion of the first torsion beam group 144a, 144b as the distance from the swing axis C increases. It is formed into a shape. With such a configuration, it is possible to suppress the generation of noise when the swing plate 6 is swung around the swing axis C, that is, around the X axis.

  The first support frame 146 is formed in a shape in which the width in the Y-axis direction becomes narrower in the vicinity of the end in the X-axis direction as the distance from the swing axis C2 increases. Vent holes 226a and 226b are formed in a portion of the first support frame 146 surrounded on three sides by the swing side bent portion, the central straight portion, and the support side bent portion of the first torsion beam groups 144a and 144b. ing. In the vicinity of the end of the first support frame 146 in the Y-axis direction, rectangular vent holes 228a and 228b having a longitudinal direction in the X-axis direction are formed. Reinforcing beams 230a and 230b are formed in the vent holes 228a and 228b. Further, in the MEMS device 222 of the present embodiment, the rocking side connecting portions of the second torsion beam groups 148a and 148b are integrated, and the vent holes 232a and 232b ( Which is an example of a third vent hole). The width of the vent holes 232a, 232b in the Y direction is formed so as to be wider as it is farther from the swing axis C2, and narrower as it is closer to the swing axis C2. The side surface of the second support frame 150 that faces the swing side bending portion of the second torsion beam groups 148a and 148b is further away from the swing side bending portion of the second torsion beam groups 148a and 148b as the distance from the swing axis C2 increases. It is formed into a shape. With this configuration, it is possible to suppress the generation of noise when the swing plate 6 and the first support frame 146 are swung around the swing axis C2, that is, around the Y axis.

(Example 19)
FIG. 29 shows the MEMS device 242 of the present embodiment. The MEMS device 242 has the same configuration as the MEMS device 2 of the first embodiment shown in FIGS. Hereinafter, only the difference of the MEMS device 242 from the MEMS device 2 of the first embodiment will be described.

  In the MEMS device 242 of this embodiment, the width La between the side surface 6a of the end portion of the swing plate 6 in the Y-axis direction and the side surface 4a of the support frame 4 and the side surface of the end portion of the swing plate 6 in the X-axis direction. The width Lb between 6b and the side surface 4b of the support frame 4 is formed to have the same size.

  Further, in the MEMS device 242 of this embodiment, the support frame 4 is formed with a vent hole 244 (which is an example of a second vent hole). The vent hole 244 is formed in the vicinity of the portion of the support frame 4 that faces the end portion of the swing plate 6 in the Y-axis direction. The ventilation hole 244 is formed in a rectangular shape having a longitudinal direction in the X-axis direction when the MEMS device 242 is viewed from above. The width of the vent hole 244 in the X-axis direction is longer than the width of the swing plate 6 in the X-axis direction.

  In the MEMS device 242 of the present embodiment, when the swing plate 6 swings, air passes through the vent hole 244, so that the air is prevented from being strongly compressed between the swing plate 6 and the support frame 4. And generation | occurrence | production of a big noise can be suppressed.

  In the MEMS device 242 of this embodiment, a vent hole 244 is formed in the vicinity of a portion of the support frame 4 that faces the end portion of the swing plate 6 in the Y-axis direction. Since the end of the swing plate 6 in the Y-axis direction swings at a high speed and with a large amplitude when the swing plate 6 swings, a large noise is likely to be generated. Like the MEMS device 242 of the present embodiment, a large noise is generated by forming the vent hole 244 in the vicinity of the portion of the support frame 4 that faces the end portion of the swing plate 6 in the Y-axis direction. Can be suppressed.

  In the various embodiments described above, the configuration of the magnetic drive in which the permanent magnet 12 is attached to the swing plate 6 and the swing plate 6 is swung by changing the magnetic field applied to the swing plate 6 has been described. However, the means for swinging the swing plate 6 is not limited to this. For example, the swing plate 6 may be swung by piezoelectric drive, the swing plate 6 may be swung by electrostatic drive, or the swing plate 6 may be swung by thermal drive.

  In the various embodiments described above, the configuration in which the swinging part is connected to the support part via the connecting part so that the swinging part can swing relative to the support part has been described. For example, the movable part is connected to the support part via the connecting part so that the movable part can translate relative to the support part, or the movable part rotates relative to the support part. The structure which the movable part is connected with the support part via the connection part so that it may become possible may be sufficient. According to the present invention, in any case, it is possible to suppress the generation of noise due to air being compressed between the movable portion and the support portion during the operation of the movable portion, as in the above-described embodiment.

  As mentioned above, although the Example of this invention was described in detail, these are only illustrations and do not limit a claim. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.

  The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

2: MEMS device; 4: Support frame; 4a: Side; 4b: Side; 4c: Side; 4d: Side; 6: Oscillating plate; 6a: Side; 6b: Side; 8: Mirror; 10c: side; 10d: side; 12a: electromagnet; 14b: electromagnet; 16: air gap; 18: air gap; 22: MEMS device; 32: MEMS device; 52: MEMS device; 62: MEMS device; 72: MEMS device; 82a: MEMS device; 84a: torsion beam group; 84b: torsion beam group; 86a: straight torsion beam; 86b: straight torsion beam; 88b: straight torsion beam; 90a: bent torsion beam; 90b: bent torsion beam; 92a: bent torsion beam; b: bent torsion beam; 94a: bent torsion beam; 94b: bent torsion beam; 96a: bent torsion beam; 96b: bent torsion beam; 98a: bent torsion beam; 98b: bent torsion beam; 102a: bending torsion beam; 102b: bending torsion beam; 104b: bending torsion beam; 106a: bending torsion beam; 106b: bending torsion beam; 108a: bending torsion beam; 108b: bending torsion beam; 112a: vent hole; 114b: vent hole; 116a: vent hole; 116b: vent hole; 122: MEMS apparatus; 132: MEMS apparatus; 142: MEMS apparatus; 144a: first torsion beam group; 144b: first torsion beam group; 146: first support frame; 148a: first support frame; 148a: second torsion beam group; 148b: second torsion beam group; 150: second support frame; 152a: first electromagnet; 152b: first electromagnet; 154a: second electromagnet; 162: MEMS device; 182: MEMS device; 192: MEMS device; 194a: first torsion beam; 194b: first torsion beam; 196: first support frame; 198a: second torsion 198b: second torsion beam; 200: second support frame; 202: vent hole; 204: vent hole; 212: MEMS device; 222: MEMS device; 224a: vent hole; 224b: vent hole; 226b: vent hole; 228a: vent hole; 228b: vent hole; 230a: reinforcing beam; 232a: Vent hole; 232b: Vent hole; 242: MEMS device; 244: Vent hole; 300: Laser radar; 302: Laser; 304: Half mirror; 306: MEMS scanner; 312: Object; 314: Reflected light; 320: Oscillating plate; 322: Support frame; 324: Torsion beam; 326: MEMS scanner; 328: Air; 330: MEMS device;

Claims (17)

A movable portion, a support portion, and a connecting portion that connects the movable portion and the support portion so that the movable portion can move relative to the support portion;
A MEMS device having a gap necessary for moving a movable part and a gap for allowing air to escape in the vicinity of a location where the movable range of the movable part is large. The movable part can swing around the swing axis with respect to the support part;
The distance between the movable part and the support part where the movable range of the movable part relative to the support part is large is larger than the distance between the movable part and the support part where the movable range of the movable part relative to the support part is small. 1 MEMS device.   The MEMS device according to claim 2, wherein an interval between the movable portion and the support portion changes gently between a portion where the movable range of the movable portion relative to the support portion is small and a portion where the movable range of the movable portion relative to the support portion is large.   The MEMS device according to claim 2, wherein the distance between the movable portion and the support portion changes rapidly between a portion where the movable range of the movable portion relative to the support portion is small and a portion where the movable range of the movable portion relative to the support portion is large. The width between the side surface closest to the movable unit and the side surface farthest from the movable unit in the direction along the swing axis of the support unit is
The MEMS device according to any one of claims 2 to 4, wherein the width of the support portion is larger than a width between a side surface closest to the movable portion and a side surface farthest from the movable portion in a direction perpendicular to the swing axis. A movable portion, a support portion, and a connecting portion that connects the movable portion and the support portion so that the movable portion can move relative to the support portion;
A MEMS device in which a first ventilation hole is formed in a movable part.   The MEMS device according to claim 6, wherein the width of the first vent hole at a location where the movable range of the movable portion relative to the support portion is large is larger than the width of the first vent hole at a location where the movable range of the movable portion relative to the support portion is small. . A movable portion, a support portion, and a connecting portion that connects the movable portion and the support portion so that the movable portion can move relative to the support portion;
A MEMS device in which a second ventilation hole is formed in a support part.   The MEMS device according to claim 1, wherein the connecting portion includes a plurality of torsion beams.   The plurality of torsion beams are arranged in the same plane, are integrated at a connection location with the movable portion, and a third ventilation hole is formed at the integrated connection location. MEMS device.   The width of the third vent hole in the portion where the movable range of the plurality of torsion beams with respect to the support portion is large is larger than the width of the third vent hole in the portion where the movable range of the plurality of torsion beams with respect to the support portion is small. The MEMS device according to claim 10.   The space between the torsion beam closest to the support portion among the plurality of torsion beams and the support portion is substantially equal to the interval between adjacent torsion beams of the plurality of torsion beams. MEMS device.   The MEMS device according to claim 1, further comprising a mirror fixed to the movable portion. A movable part is a second movable part, a second support part, and a second connection part that couples the second movable part and the second support part so that the second movable part can move relative to the second support part. Further comprising
The MEMS device according to any one of claims 1 to 13, wherein the connecting portion connects the second support portion and the support portion so that the second support portion is movable relative to the support portion.   The width of the second support portion at a location where the movable range of the second support portion relative to the support portion is large is smaller than the width of the second support portion at a location where the movable range of the second support portion relative to the support portion is small. MEMS device.   The third support portion, and further comprising a third connection portion that connects the support portion and the third support portion so that the support portion is movable relative to the third support portion. The MEMS device according to one item.   The MEMS device according to claim 16, wherein the width of the movable portion at a location where the movable range of the movable portion relative to the support portion is large is smaller than the width of the movable portion at a location where the movable range of the movable portion relative to the support portion is small.

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