JP2007295731A - Actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an actuator in which a mechanism of detecting the behavior of a mass part can be achieved easily and at low cost without performing a special process to the mass portion. <P>SOLUTION: The actuator 1 is configured to rotate first mass parts 21, 22 while deforming a first elastic connection part 25 by twisting and, as a result, to rotate a second mass part 23 while deforming a second elastic connection part 26 by twisting. In this second elastic connection part 26, passing-through portions 263 are formed which pass through in the direction perpendicular to rotational center shafts 27 of the first mass parts 21, 22 and/or the second mass part 23. A light emitter emits light toward the passing through portion 263. The light that passes through the passing-through portion 263 is received by a light receiver. Based on the amount of light received by the light receiver, the behavior of the second mass part 23 is detected. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an actuator.

For example, as an optical scanner for performing drawing by optical scanning with a laser printer or the like, an optical scanner using an actuator composed of a torsional vibrator is known (for example, see Patent Document 1).
Patent Document 1 discloses an actuator including a torsional vibrator having a one-degree-of-freedom vibration system. Such an actuator has a structure in which a plate-like mass portion is supported on both sides by a torsion spring as a torsional vibrator of a one-degree-of-freedom vibration system. A light reflecting portion having light reflectivity is provided on the mass portion, and the mass portion is rotationally driven while torsionally deforming the torsion spring, and the light reflecting portion reflects and scans the light. Thereby, drawing can be performed by optical scanning.

In particular, in the actuator according to Patent Document 1, a through-hole penetrating in the thickness direction is formed in the mass portion, and light is emitted from one surface side of the mass portion toward the through-hole and passes through the through-hole. The received light is received on the other surface side of the mass part, and the amount of light received is measured to detect the rotation angle of the mass part. By rotating the mass unit based on such a detection result, the behavior of the mass unit can be made desired.
In such an actuator, the behavior of the mass portion can be detected without providing electrical wiring to the mass portion or the torsion spring. As a result, the manufacture of the actuator is simple and inexpensive.

However, in the actuator according to Patent Document 1, the through hole as described above is provided in the mass portion, and both the behavior detection light and the light scanning light are used together. And the characteristics as an optical scanner are deteriorated.
In order to prevent this, it is assumed that a through-hole is provided in a portion of the mass portion outside the region for optical scanning, and behavior detection light is irradiated separately from the optical scanning light to such a through-hole. If it comprises, the freedom degree of design of an actuator will become low by enlargement of a mass part etc.

JP 2003-5124 A

  An object of the present invention is to provide an actuator capable of realizing a mechanism for detecting the behavior of a mass part easily and inexpensively without subjecting the mass part to special processing.

Such an object is achieved by the present invention described below.
The actuator of the present invention includes a mass part,
A support part for supporting the mass part;
An elastic connecting part that connects the mass part and the support part so that the mass part is rotatable with respect to the support part;
Driving means for generating a driving force for rotating the mass section;
Behavior detecting means for detecting the behavior of the mass part,
An actuator configured to actuate the driving unit based on a detection result of the behavior detecting unit and rotate the mass unit while twisting and deforming the elastic coupling unit;
The elastic connecting portion is formed with a penetrating portion penetrating in a direction perpendicular to the rotation center axis of the mass portion,
The behavior detection unit includes a light emitting unit that emits light toward the penetrating part and a light receiving unit that receives light that has passed through the penetrating part, and is based on the amount of light received by the light receiving unit. The mass portion is configured to detect the behavior of the mass portion.
Thereby, it is possible to realize a mechanism for detecting the behavior of the mass part easily and inexpensively without performing special processing on the mass part.

The actuator of the present invention includes a first mass part,
A support part for supporting the first mass part;
A first elastic connecting portion that connects the first mass portion and the support portion so that the first mass portion is rotatable with respect to the support portion;
A second mass part;
A second elastic connecting portion for connecting the first mass portion and the second mass portion so that the second mass portion is rotatable with respect to the first mass portion;
Driving means for generating a driving force for rotating the first mass unit;
Behavior detecting means for detecting the behavior of the second mass part,
Based on the detection result of the behavior detecting means, the driving means is operated to rotate the first mass portion while twisting and deforming the first elastic connecting portion. Accordingly, the second elastic connecting portion is rotated. An actuator configured to rotate the second mass portion while twisting and deforming the portion,
The first elastic connecting portion and / or the second elastic connecting portion includes a through portion penetrating in a direction perpendicular to the rotation center axis of the first mass portion and / or the second mass portion. Formed,
The behavior detection unit includes a light emitting unit that emits light toward the penetrating part and a light receiving unit that receives light that has passed through the penetrating part, and is based on the amount of light received by the light receiving unit. The second mass unit is configured to detect the behavior of the second mass unit.
Thereby, the mechanism which detects the behavior of the 2nd mass part simply and cheaply can be realized, without giving special processing to the 1st mass part or the 2nd mass part.

In the actuator according to the aspect of the invention, it is preferable that the second mass portion has a plate shape, and the penetration portion penetrates in a thickness direction of the second mass portion in a non-driven state.
Accordingly, when the actuator is manufactured, the first mass portion, the first elastic connection portion, the support portion, the second mass portion, the second elastic connection portion, and the through portion are formed by processing such as etching once on the substrate. Can be easily formed collectively. As a result, the manufacturing cost of the actuator can be reduced, and consequently the cost of the actuator can be reduced.

In the actuator according to the aspect of the invention, it is preferable that a plurality of the through portions are provided, and the light receiving portion is configured to receive light that has passed through the plurality of through portions.
As a result, it is possible to provide the through portion only at the place optimal for light reception of the first elastic coupling portion and the second elastic coupling portion, while maintaining the strength of the first elastic coupling portion and the second elastic coupling portion. The amount of light received by the light receiving unit can be increased.

In the actuator according to the aspect of the invention, it is preferable that the plurality of through portions are arranged along the rotation center axis.
The torsional amounts of the first elastic connecting portion and the second elastic connecting portion are different at both ends thereof. For example, the amount of twist of the second elastic connecting portion is maximized near the second mass portion, and is minimized at the portion close to the first mass portion. A plurality of penetrating portions are arranged in the first elastic connecting portion and the second elastic connecting portion along the rotation center axis, and light passing through the plurality of penetrating portions is received at a time by the light receiving portion. Further, it is possible to reduce unevenness in the amount of light received by the light receiving unit due to the position of the penetrating part, and to increase the detection accuracy of the behavior of the second mass unit.

In the actuator according to the aspect of the invention, it is preferable that the penetration portion is formed in the second elastic coupling portion.
Thereby, since the width of the change in the amount of light received by the light receiving unit with respect to the rotation of the second mass unit can be increased, the behavior of the second mass unit can be detected more accurately. This is because the second elastic connecting portion is torsionally deformed more than the first elastic connecting portion.

In the actuator according to the aspect of the invention, it is preferable that the through portion has a longitudinal shape extending along the rotation center axis.
Thereby, since the width of the change in the amount of light received by the light receiving unit with respect to the rotation of the second mass unit can be increased, the behavior of the second mass unit can be detected more accurately.
In the actuator according to the aspect of the invention, the first elastic connection portion and / or the second elastic connection portion may be configured by two rod-shaped connection members that are opposed to each other with an interval through the rotation center axis. The penetrating portion is preferably a space between the two rod-like connecting members.
Thereby, the whole of the first elastic connecting portion and the second elastic connecting portion can be twisted and deformed by mainly bending and deforming each rod-like connecting member. Therefore, the stress which arises in the 1st elastic connection part or the 2nd elastic connection part can be reduced, and the reliability and durability of an actuator can be improved.

In the actuator of the present invention, the actuator may include a light-shielding part that is provided with a gap between the first elastic coupling part and / or the second elastic coupling part in which the penetrating part is formed. preferable.
Thereby, it can suppress that the light from a light emission part turns around from the outer side of a 1st elastic connection part or a 2nd elastic connection part, without passing through a penetration part, and reaches | attains a light-receiving part. . Therefore, the behavior of the second mass part can be detected more accurately.

In the actuator according to the aspect of the invention, it is preferable that the light receiving unit also receives light that has passed through the gap.
Thereby, since the width of the change in the amount of light received by the light receiving unit with respect to the rotation of the second mass unit can be increased, the behavior of the second mass unit can be detected more accurately.
In the actuator according to the present invention, when the length of the penetrating portion in the penetrating direction is A and the width of the penetrating portion in the direction perpendicular to the rotation center axis is B, B / A is 1 × 10 ^-3 is preferably to 1.
Thereby, since the width of the change in the amount of light received by the light receiving unit with respect to the rotation of the second mass unit can be increased, the behavior of the second mass unit can be detected more accurately.

In the actuator according to the aspect of the invention, in the non-driven state of the first mass portion and the second mass portion, the incident direction of the light to the penetration portion may be substantially the same as the penetration direction of the penetration portion. preferable.
Thereby, even if the amplitude of the second mass unit is small, the behavior of the second mass unit can be detected.

In the actuator of the present invention, the base on which the first mass part, the support part, the first elastic coupling part, the second mass part, and the second elastic coupling part are formed, and the base It is preferable that the light emitting unit and / or the light receiving unit be provided on the support.
Thereby, the light emitting part and the light receiving part are fixedly provided to the base, and the behavior of the second mass part can be detected more accurately.
In the actuator of the present invention, it is preferable that a light reflecting part having light reflectivity is provided on the second mass part.
Thereby, the actuator of this invention is applicable to optical devices, such as an optical scanner, an optical switch, and an optical attenuator.

The actuator of the present invention includes a mass part,
A support part for supporting the mass part;
An elastic connecting part that connects the mass part and the support part so that the mass part is rotatable with respect to the support part;
Driving means for generating a driving force for rotating the mass section;
Behavior detecting means for detecting the behavior of the mass part,
An actuator configured to actuate the driving unit based on a detection result of the behavior detecting unit and rotate the mass unit while twisting and deforming the elastic coupling unit;
A light-shielding part provided with a gap between at least one of the mass part and the elastic coupling part, and having a light-shielding property;
The behavior detecting means includes a light emitting unit that emits light toward the gap, and a light receiving unit that receives the light that has passed through the gap, and based on the amount of light received by the light receiving unit, It is comprised so that the behavior of a mass part may be detected.
Thereby, it is possible to realize a mechanism for detecting the behavior of the mass part easily and inexpensively without performing special processing on the mass part. In particular, a mechanism for detecting the behavior of the mass portion can be realized easily and inexpensively without processing the elastic connecting portion.

The actuator of the present invention includes a first mass part,
A support part for supporting the first mass part;
A first elastic connecting portion that connects the first mass portion and the support portion so that the first mass portion is rotatable with respect to the support portion;
A second mass part;
A second elastic connecting portion for connecting the first mass portion and the second mass portion so that the second mass portion is rotatable with respect to the first mass portion;
Driving means for generating a driving force for rotating the first mass unit;
Behavior detecting means for detecting the behavior of the second mass part,
Based on the detection result of the behavior detecting means, the driving means is operated to rotate the first mass portion while twisting and deforming the first elastic connecting portion. Accordingly, the second elastic connecting portion is rotated. An actuator configured to rotate the second mass portion while twisting and deforming the portion,
There is provided a light-shielding part having a light-shielding property and provided with a gap with respect to at least one of the first mass part, the first elastic coupling part, the second mass part, and the second elastic coupling part. And
The behavior detecting means includes a light emitting unit that emits light toward the gap, and a light receiving unit that receives the light that has passed through the gap, and based on the amount of light received by the light receiving unit, It is comprised so that the behavior of a mass part may be detected.
Thereby, the mechanism which detects the behavior of the 2nd mass part simply and cheaply can be realized, without giving special processing to the 1st mass part or the 2nd mass part. In particular, a mechanism for detecting the behavior of the second mass part can be realized easily and inexpensively without applying special processing to the first elastic connection part and the second elastic connection part.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of an actuator of the invention will be described with reference to the accompanying drawings.
<First Embodiment>
First, a first embodiment of the actuator of the present invention will be described.
1 is a plan view (internal perspective view) showing a first embodiment of the actuator of the present invention, FIG. 2 is a cross-sectional view taken along line AA in FIG. 1, and FIG. 3 is a line BB in FIG. FIG. 4 is a cross-sectional view, FIG. 4 is a plan view showing the arrangement of electrodes for driving the actuator shown in FIG. 1, and light emitting and receiving parts for detecting behavior, and FIG. 5 is a diagram of a control system in the actuator shown in FIG. FIG. 6 is a block diagram showing a schematic configuration, FIG. 6 is a diagram for explaining behavior detection of the second mass part in the actuator shown in FIG. 1, and FIG. 7 is a diagram showing an example of a drive voltage in the actuator shown in FIG. FIG. 8 is a graph showing the relationship between the frequency of the drive voltage and the amplitude of the first mass part and the second mass part when an AC voltage is used as the drive voltage. In the following, for convenience of explanation, the front side of the paper in FIGS. 1 and 4 is referred to as “up”, the back side of the paper is referred to as “down”, the right side is referred to as “right”, and the left side is referred to as “left”. The upper side in 3 is called “upper”, the lower side is called “lower”, the right side is called “right”, and the left side is called “left”.

The actuator 1 has a base 2 having a two-degree-of-freedom vibration system as shown in FIG. 1, and a support 3 is joined to the lower part of the base 2 as shown in FIGS. A light transmissive support 4 is joined to the upper portion of the base 2. On the support 4, four electrodes 32 for driving the two-degree-of-freedom vibration system by electrostatic attraction are provided.
In the actuator 1 according to this embodiment, a two-degree-of-freedom vibration system of the base 2 is driven between the support 3 and the support 4 by applying a voltage to the electrode 32. .

In particular, the actuator 1 of the present embodiment emits light from the light emitting unit 43 provided on the upper surface of the support 4 and is based on the amount of light received by the light receiving unit 33 provided on the lower surface of the support 3. The behavior of the two-degree-of-freedom vibration system is detected, and the two-degree-of-freedom vibration system is driven based on the detection result.
Hereinafter, each part which comprises the actuator 1 is demonstrated in detail sequentially.

The base 2 includes a pair of first mass units (drive units) 21 and 22 and a second mass unit (movable unit) 23 provided between the pair of first mass units (drive units) 21 and 22. And a frame-like support portion 24 provided so as to surround these mass portions.
Specifically, the base body 2 is provided with a first mass portion 21 on one end side (left side in FIGS. 1 and 2) around the second mass portion 23 and on the other end side (FIG. 1 and FIG. 2). The first mass unit 22 is provided on the right side in FIG.

In the present embodiment, the first mass parts 21 and 22 have substantially the same shape and the same dimensions as each other, and are provided substantially symmetrically via the second mass part 23.
A light reflecting portion 231 having light reflectivity is provided on the upper surface of the second mass portion (movable portion) 23 (the surface on the support 4 side described later). Thereby, the actuator 1 can be applied to an optical device such as an optical scanner, an optical switch, or an optical attenuator.

Further, as shown in FIGS. 1 and 2, the base body 2 includes a pair of first elastic connecting portions 25 and 25 that connect the first mass portions 21 and 22 and the support portion 24, and a first mass portion. 21 and 22 and the second mass part 23 are provided with a pair of second elastic connection parts 26 and 26.
The first elastic connecting portions 25, 25 and the second elastic connecting portions 26, 26 are provided coaxially, and the first mass portion 21 is set with the rotation central axis (rotating shaft) 27 as a center axis. , 22 can rotate with respect to the support portion 24, and the second mass portion 23 can rotate with respect to the first mass portions 21, 22.

  In particular, each second elastic connecting portion 26 is constituted by two rod-like connecting members 261 and 262 that are opposed to each other with a space therebetween via a rotation center shaft 27. As a result, between the two rod-like connecting members 261 and 262, it penetrates in the vertical direction (thickness direction of the plate-like second mass portion 23 and the like) and extends along the rotation center axis 27. A through portion 263 is formed as a space having a longitudinal shape. These two rod-like connecting members 261 and 262 connect the first mass part 21 or the first mass part 22 and the second mass part 23, respectively.

In such a second elastic connecting portion 26, the entire second elastic connecting portion 26 can be torsionally deformed by mainly bending and deforming the rod-like connecting members 261 and 262 in opposite directions. . Therefore, the stress generated in the second elastic connecting portion 26 can be reduced, and the reliability and durability of the actuator 1 can be improved.
Further, when the length of the penetrating portion 263 in the penetrating direction is A and the width of the penetrating portion 263 in the direction perpendicular to the rotation center axis 27 is B, B / A is 1 × 10 ⁻³ to 1 Is preferred. Thereby, the width of the change in the amount of light received by the light receiving unit 33 with respect to the rotation of the second mass unit 23 can be increased, and the behavior of the second mass unit 23 can be detected more accurately.

Moreover, the length A in the penetration direction of the penetration part 263 is not specifically limited, For example, it is preferable that it is 100 micrometers-3 mm, and it is more preferable that it is 500 micrometers-1 mm.
Further, the width B of the through portion 263 in the direction perpendicular to the rotation center axis 27 is preferably, for example, 10 to 300 μm, and more preferably 30 to 100 μm.
Further, the length D and the width C of the gap 264 preferably have the same relationship as the length A and the width B of the penetrating portion 263 described above. Thereby, the width of the change in the amount of light received by the light receiving unit 33 with respect to the rotation of the second mass unit 23 can be increased, and the behavior of the second mass unit 23 can be detected more accurately.

Further, as shown in FIGS. 1 and 3, the support portion 24 is provided with light shielding portions 241 and 242 having a light shielding property, which are provided at a distance from the second elastic connecting portion 26 described above. .
The light shielding portion 241 protrudes from the inside of the frame-shaped support portion 24 toward the rod-like connecting member 262 of the second elastic connecting portion 26, and the tip thereof faces the rod-like connecting member 262 with a gap 264. It is formed as follows.

Similarly, the light shielding portion 242 protrudes from the inside of the frame-shaped support portion 24 toward the rod-like connection member 261 of the second elastic connection portion 26, and the tip thereof is a gap 265 with respect to the rod-like connection member 261. It is formed so as to face each other.
As described above, the base 2 includes the first vibration system including the first mass portions 21 and 22 and the first elastic coupling portions 25 and 25, the second mass portion 23 and the second elastic coupling portion 26. , 26 and a second vibration system comprising a second degree of freedom vibration system.

  Such a two-degree-of-freedom vibration system is formed thinner than the entire thickness of the base 2 and is located at the center of the base 2 in the vertical direction in FIG. In other words, the base 2 is formed with a portion (hereinafter referred to as a thin portion) thinner than the entire thickness of the base 2, and the first mass portion is formed by forming a deformed hole in the thin portion. 21, 22, the second mass portion 23, the first elastic coupling portions 25, 25, the second elastic coupling portions 26, 26, and the light shielding portions 241, 242 are formed.

The thin portion is formed in the base 2 by providing the base 2 with a concave portion 28 opening upward and a concave portion 29 opening downward. In the present embodiment, the depth of the recess 28 and the depth of the recess 29 are substantially the same.
Such a base body 2 is composed of silicon as a main material, and includes first mass portions 21, 22, second mass portions 23, a support portion 24, and first elastic coupling portions 25, 25. The second elastic connecting portions 26 and 26 are integrally formed. As a result, (1) the manufacturing process is reduced and the cost is reduced. (2) Since it is an integrated type, failure such as cracks can be avoided. (3) Design as an elastic body becomes easy.

The support 3 is composed of, for example, various types of glass and silicon as a main material.
In the present embodiment, the support 3 has light transmittance. As a result, a light receiving portion 33 (described later) provided on the outer side (opposite side of the base 2) with respect to the support 3 can receive light that has passed through the through portion 263 and the like. It is also possible to provide the light receiving portion 33 on the inner side (base 2 side) with respect to the support 3. In this case, the support 3 may not have light transmittance.

As shown in FIGS. 2 and 4, a recess 31 is formed on the upper surface of the support 3 at a portion corresponding to the second mass portion 23.
The recess 31 constitutes an escape portion that prevents the second mass portion 23 from contacting the support body 3 when the second mass portion 23 rotates (vibrates). By providing the concave portion (relief portion) 31, the deflection angle (amplitude) of the second mass portion 23 can be set larger while preventing the actuator 1 from being enlarged. In addition, when the depth of the recessed part 29 is large with respect to the deflection angle (amplitude) of the 2nd mass part 23, the recessed part 31 does not need to be provided.

  Further, as shown in FIG. 4, a pair of electrodes 32 are provided on the upper surface of the support 3 so as to be substantially symmetric about the rotation center axis 27 at a portion corresponding to the first mass portion 21. In addition, a pair of electrodes 32 is provided in a portion corresponding to the first mass portion 22 so as to be substantially symmetric about the rotation center axis 27. That is, in this embodiment, two pairs (a total of four) of the pair of electrodes 32 are provided.

Each electrode 32 is connected to an energization circuit 13 to be described later, and is configured such that an AC voltage (drive voltage) can be applied between the first mass parts 21 and 22 and each electrode 32. That is, the energization circuit 13 and each electrode 32 constitute a driving unit that generates a driving force for rotationally driving the first mass parts 21 and 22.
In addition, the 1st mass parts 21 and 22 are each provided with the insulating film (not shown) in the surface facing each electrode 32. As shown in FIG. Thereby, it is prevented suitably that the short circuit between the 1st mass parts 21 and 22 and each electrode 32 occurs.

  On the lower surface of the support 3, a light receiving unit 33 that receives light that has passed through a light emitting unit 43 (described later) and a through part 263 and gaps 264 and 265 (hereinafter also referred to as a through part 263) is provided.

The light receiving unit 33 receives light from the light emitting unit 43 described later. Further, as shown in FIGS. 3 and 4, the light receiving portion 33 is disposed at a position corresponding to each second elastic coupling portion 26 (more specifically, the through portion 263) in plan view.
For example, the light receiving unit 33 includes a light receiving element, and the light receiving element is bonded to the lower surface of the support.

  The light receiving element is not particularly limited as long as it can receive light that has passed through the penetrating portion 263 and the like (light from the light emitting portion 43). Photoelectric tube, photomultiplier tube, photoconductive cell, photo Various light receiving elements such as a diode, a phototransistor, an avalanche photodiode, and a pyroelectric infrared element can be used. For example, a phototube, a photomultiplier tube, and a photodiode can be preferably used.

Note that the installation location of the light receiving element may not be the lower surface of the support 3. In this case, an optical waveguide such as an optical fiber can be provided on the lower surface of the support 3 so that light that has passed through the penetrating portion 263 and the like is received by the light receiving element via the optical waveguide.
Such a light receiving unit 33 (light receiving element) is connected to the control circuit 14 that controls the driving of the driving means described above (specifically, driving of the energization circuit 13). Thereby, the drive of the actuator 1 can be controlled based on the detection result of the light receiving unit 33.

  The support 4 has a function of causing external light to enter the light reflecting portion 231 and leading the light reflected by the light reflecting portion 231 to the outside. For this reason, the support body 4 is comprised by the board | substrate which was excellent in flatness and excellent in the light transmittance, for example, various glass substrates. Further, a light emitting unit 43 described later provided on the outer side (opposite side of the base 2) with respect to the support 4 can irradiate light toward the penetrating portion 263 and the like. It is also possible to provide the light receiving part 43 on the inner side (base 2 side) with respect to the support 4.

  In the actuator 1 of the present embodiment, the base body 2, the support body 3, and the support body 4 form an airtight space. Specifically, the recess 31 and the recesses 28 and 29 communicate with each other, and these form an airtight space. In such an airtight space, the first mass parts 21 and 22, the second mass part 23, the first elastic connection parts 25 and 25, and the second elastic connection parts 26 and 26 are arranged. .

With such a configuration, the characteristics of the actuator 1 can be made excellent.
Specifically, I: It is easy to secure a space where the first mass parts 21 and 22 and the second mass part 23 can vibrate.
II: Foreign matter such as dust can be prevented from entering the actuator 1 (in the airtight space). III: The first mass parts 21 and 22 and the second mass part 23 vibrate (rotate) when the inside of the actuator 1 (in the airtight space) is in a reduced pressure state or filled with an inert gas or the like. ), The air resistance generated at the time is reduced, and vibration (rotation) at a larger angle becomes possible. As a result, the actuator 1 can be made highly reliable.

Further, IV: It is not necessary to process the support 4 by etching or the like to secure a space where the first mass portions 21 and 22 and the second mass portion 23 can vibrate. In particular, the flatness of the recess 28 side is ensured (that is, the surface is prevented from being roughened). Thereby, in the support body 4, it is prevented or reduced that incident light and reflected light scatter, etc., As a result, the actuator 1 can obtain a high reflectance.
In particular, in this embodiment, the light receiving unit 33 and the light emitting unit 43 are provided outside the support 3 and the support 4 (that is, the lower side of the support unit 3 and the upper side of the support unit 4 in FIG. 2). When forming the light receiving unit 33 and the light emitting unit 43, the airtight space is formed in advance, thereby preventing adverse effects on the vibration system.

Here, there are various indexes indicating the flatness of the surface of the support 4. For example, surface roughness (centerline average roughness specified in JIS B 0601) Ra is preferably used.
Specifically, the surface roughness Ra of the support 4 is preferably 1 μm or less, more preferably 100 nm or less, and even more preferably about 1 nm to 100 nm. If the surface roughness exceeds the upper limit, depending on the constituent material, thickness, etc. of the support 4, the loss of incident light and reflected light increases, and sufficient reflectivity may not be obtained.

  The average depth of the recesses 28 and 29 is appropriately set according to the dimensions of the first mass parts 21 and 22 and the second mass part 23 (actuator 1), and is not particularly limited, but is about 1 to 2000 μm. It is preferable that it is about 5-10 micrometers. If the average depth is too thin, a sufficient distance between each mass part 21, 22, 23 and the support 3 or the support 4 cannot be ensured, and the touch angle of each mass part 21, 22, 23 ( It may be difficult to set a large displacement angle. On the other hand, if the average depth is too thick, the distance between the respective mass parts 21, 22, 23 and the support 3 or the support 4 becomes unnecessarily large, which leads to an increase in the size of the actuator 1, which is not preferable.

On the upper surface of the support 4, a light emitting portion 43 that emits light (irradiates light) toward the above-described through portion 263 and the like is provided.
The light emitting part 43 emits light toward the penetrating part 263 and the gaps 264 and 265.
Such a light emitting unit 43 includes, for example, a light emitting element, and the light emitting element is bonded to the upper surface of the support 4.

The light emitting element is not particularly limited, and various light emitting elements can be used. For example, a light emitting diode, a light emitting FET, an EL element, or the like can be preferably used.
Note that the installation location of the light emitting element may not be the lower surface of the support 4. In this case, an optical waveguide such as an optical fiber can be provided on the lower surface of the support 4 so that light can be emitted from the light emitting element toward the penetrating portion 263 and the like via the optical waveguide.

Hereinafter, the control system of the actuator 1 will be described in detail with reference to FIG.
As shown in FIG. 5, in the actuator 1 of the present embodiment, the electrode 32 described above is connected to the energization circuit 13. The energization circuit 13 selectively applies a voltage (generates a potential difference) between each electrode 32 and the first mass parts 21 and 22.
The energization circuit 13 is connected to a control circuit 14 having a function of controlling driving of the energization circuit 13.

The control circuit 14 is connected to the light receiving unit 33 described above, and the control circuit 14 controls the drive of the energization circuit 13 based on the detection result of the light receiving unit 33.
That is, the control circuit 14 detects the behavior of the second mass unit 23 based on the intensity of light received by the light receiving unit 33 (the amount of received light), and drives the drive means (energization) based on the detection result. A function of controlling the driving of the circuit 13).

  In other words, the control circuit 14, the light emitting unit 43, and the light receiving unit 33 constitute a behavior detecting unit that detects the behavior of the second mass unit 23, and the control circuit 14 is detected by the behavior detecting unit. Control means for controlling the drive of the drive means based on the behavior is configured. Thereby, the 1st mass parts 21 and 22 and / or the 2nd mass part 23 can be driven stably.

More specifically, the control circuit 14 includes a CPU 141, an AD conversion circuit 142, a ROM 143, and a RAM 144 as shown in FIG.
The CPU 141 is connected to the energization circuit 13 and is connected to the light receiving unit 33 (light receiving element) via the AD conversion circuit 142.
The AD conversion circuit 142 converts the output of the light receiving unit 33 from analog to digital.

The ROM 143 stores a program for calculating the behavior of the second mass unit 23 based on the detected intensity of the light receiving unit 33, a program for controlling the energization circuit 13 based on the calculated behavior, and the like. .
The RAM 144 has a function of storing a program, a value calculated by the program, and the like.

The CPU 141 detects the behavior of the second mass unit 23 based on the detection intensity digitized by the AD conversion circuit 142 in accordance with a program stored in the ROM 143. In addition, the CPU 141 controls the energization circuit 13 according to the program stored in the ROM 143 so that the behavior of the second mass unit 23 is desired based on the detected behavior.
The actuator 1 having the above configuration is driven as follows.

  That is, for example, a sine wave (AC voltage) or the like is applied between the first mass parts 21 and 22 and each electrode 32. Specifically, for example, the first mass parts 21 and 22 are grounded, and a voltage having a waveform as shown in FIG. 7A is applied to the upper two electrodes 32 in FIG. A voltage having a waveform as shown in FIG. 7B is applied to the middle and lower electrodes 32. Then, electrostatic force (Coulomb) is alternately provided between the first mass parts 21 and 22 and the upper electrode 32 in FIG. 4 and between the first mass parts 21 and 22 and the lower electrode 32 in FIG. Force).

Due to this electrostatic force, the force that the first mass portions 21 and 22 are attracted toward the electrodes 32 changes depending on the phase of the sine wave, and the rotation center shaft 27 (the first elastic coupling portion 25) serves as an axis. Then, it vibrates (rotates) so as to be inclined with respect to the plate surface of the substrate 2 (paper surface in FIG. 1).
The second mass portion 23 connected via the second elastic connecting portion 26 with the vibration (drive) of the first mass portions 21 and 22 is also connected to the rotation center shaft 27 (second The elastic coupling portion 26) is vibrated (rotated) so as to be inclined with respect to the plate surface of the base 2 (the paper surface in FIG. 1).
At this time, if the entire second elastic coupling portion 26 is twisted and deformed, the area of the through portion 263 and the gaps 264 and 265 in plan view changes according to the degree of the deformation. Such a change in area corresponds to the behavior of the second mass portion 23. Therefore, the behavior (more specifically, amplitude, frequency, etc.) of the second mass part can be detected by utilizing such a phenomenon.

Hereinafter, based on FIG. 6, the detection of the behavior of the 2nd mass part 23 is demonstrated concretely.
As shown in FIG. 6A, when the second mass portion 23 is in a non-driven state (that is, the actuator 1 is in a non-driven state), the respective areas in plan view of the penetrating portion 263 and the gaps 264 and 265 are as follows. Is the largest.
Then, when the second mass portion 23 vibrates (rotates) as described above, as shown in FIGS. 6B and 6C, the through portion 263 and the gaps 264 and 265 in plan view, respectively. The area is reduced.

Here, the rotation angle of the second mass portion 23 in FIG. 6C is larger than the rotation angle of the second mass portion 23 in FIG. 6B, and the through portion 263 in FIG. 6C. The respective areas of the gaps 264 and 265 in plan view are smaller than the respective areas of the through portion 263 and the gaps 264 and 265 in plan view in FIG.
In addition, the light receiving unit 33 receives light that has passed through each of the through part 263 and the gaps 264 and 265. That is, the amount of light received by the light receiving unit 33 is the sum of the light that has passed through the through portion 263, the light that has passed through the gap 264, and the light that has passed through the gap 265.

Further, when the rotation angle of the second mass portion 23 is maximum, that is, when the degree of torsional deformation of the second elastic coupling portion 26 is maximum, each of the penetrating portion 263 and the gaps 264 and 265 in plan view is shown. The area is minimized. Accordingly, the amount of light received by the light receiving unit 33 is minimized.
On the other hand, when the rotation angle of the second mass unit 23 is the minimum, that is, when the second mass unit 23 is in the non-driven state, the respective areas of the through portion 263 and the gaps 264 and 265 in plan view are the maximum. It becomes. Therefore, the amount of light received by the light receiving unit 33 is maximized.

Thus, since the behavior of the second mass unit 23 and the amount of light received by the light receiving unit 33 have a correlation, the behavior of the second mass unit 23 is based on the amount of light received by the light receiving unit 33. Can be detected.
Thus, the structure which detects the behavior of the 2nd mass part 23 does not give special processing to the 1st mass part 21 and 22 and the 2nd mass part 23, and the 1st mass part 21 and 22 is carried out. In addition, the design freedom such as the shape, size, and mass of the second mass portion 23 is not impaired. Therefore, a mechanism for detecting the behavior of the second mass unit 23 can be realized easily and inexpensively.

  Further, since the penetrating portion 263 or the like penetrates in the thickness direction of the second mass portion 23 in the non-driven state, the first mass portion is obtained by processing such as etching once on the substrate when the actuator 1 is manufactured. 21, 22, the first elastic connecting portion 25, the support portion 24, the second mass portion 23, the second elastic connecting portion 26, and the penetrating portion 263 can be easily formed collectively. As a result, the manufacturing cost of the actuator 1 can be reduced, and consequently the cost of the actuator 1 can be reduced.

  In addition, since the penetrating portion 263 is formed in the second elastic coupling portion 26, the width of the change in the amount of light received by the light receiving portion 33 with respect to the rotation of the second mass portion 23 can be increased. The behavior of the second mass portion 23 can be detected more accurately. This is because the second elastic connecting portion 26 is torsionally deformed more than the first elastic connecting portion 25 when the second mass portion 23 is driven.

Further, since the penetrating portion 263 has a longitudinal shape extending along the rotation center axis 27, the width of the change in the amount of light received by the light receiving portion 33 with respect to the rotation of the second mass portion 23 also in this respect. And the behavior of the second mass part 23 can be detected more accurately.
Further, since the light shielding parts 241 and 242 are provided with a gap with respect to the second elastic coupling part 26 in which the through part 263 is formed, the light from the light emitting part 43 does not pass through the through part 263 and is not used. Intentionally, it can be prevented that the second elastic coupling portion 26 wraps around from the outside and reaches the light receiving portion 33. Therefore, also in this respect, the behavior of the second mass unit 23 can be detected more accurately.

In addition, since the light receiving unit 33 also receives the light that has passed through the gaps 264 and 265, the width of the change in the amount of light received by the light receiving unit 33 with respect to the rotation of the second mass unit 23 also in this respect. And the behavior of the second mass part 23 can be detected more accurately.
Further, in the non-driven state of the first mass parts 21, 22 and the second mass part 23, the incident direction of light from the light emitting part 43 to the penetration part 263 is substantially the same as the penetration direction of the penetration part 263. Therefore, even if the amplitude of the second mass unit 23 is small, the behavior of the second mass unit 23 can be detected.

Further, since the light emitting part 43 is provided on the support 4 and the light receiving part 33 is provided on the support 3, the light emitting part 43 and the light receiving part 33 are fixedly provided on the base 2, and The behavior of the second mass portion 23 can be detected more accurately.
Further, in the present embodiment, since the penetrating portion 263 is provided in both of the pair of second elastic coupling portions 26, 26, one of the pair of second elastic coupling portions 26, 26 is connected to the other. The spring characteristic can be easily set to the same characteristic, and also in this respect, the degree of freedom in designing the actuator 1 is increased.

Further, since the light receiving portions 33 are provided corresponding to the two penetrating portions 263, also in this respect, the width of the change in the amount of light received by the light receiving portion 33 with respect to the rotation of the second mass portion 23 is increased. Thus, the behavior of the second mass unit 23 can be detected more accurately.
Further, in the actuator 1, as described above, the concave portion 31 is formed in the portion of the support 3 corresponding to the second mass portion 23, and the concave portion 29 is formed on the lower surface of the base 2 in FIG. A concave portion 28 is formed in the first concave portion 28 and the first mass portions 21 and 22 are provided in the concave portions 28 and 29 in a plan view.

  With such a configuration, a large space is secured as a space where the second mass portion 23 can vibrate and a space where the first mass portions 21 and 22 can vibrate. Accordingly, by setting the masses of the first mass parts 21 and 22 to be relatively small, the first mass parts 21 and 22 are vibrated with a large deflection angle, or the second mass part 23 is further resonant. Thus, even when the vibrator vibrates with a large deflection angle, it is possible to suitably prevent the respective mass parts 21, 22, 23 (two-degree-of-freedom vibration system) from contacting the support 3 and the support 4.

For this reason, when such an actuator 1 is applied to, for example, an optical scanner, scanning with higher resolution can be performed.
Further, the distance (length) from the end portion 211 in the direction (longitudinal direction) substantially perpendicular to the rotation center axis 27 of the first mass unit 21 is L _1, and the first mass unit 22. against the rotational axis 27, substantially perpendicular distance (length) between the end 221 of the (longitudinal) and L _2, with respect to the rotational axis 27 of the second mass 23 Te, when the distance between the end 232 of the substantially vertical direction (length) was set to L _3, in the present embodiment, the first mass portions 21 and 22 is, because it is provided independently The first mass parts 21 and 22 and the second mass part 23 do not interfere with each other, and L ₁ and L ₂ are reduced regardless of the size (length L ₃ ) of the second mass part 23. be able to. Thereby, the rotation angle (swing angle) of the 1st mass parts 21 and 22 can be enlarged, and the rotation angle of the 2nd mass part 23 can be enlarged.

In addition, by reducing L ₁ and L ₂ , the distance between the first mass parts 21 and 22 and each electrode 32 can be reduced, thereby increasing the electrostatic force and the first mass. The alternating voltage applied to the parts 21 and 22 and each electrode 32 can be reduced.
Here, it is preferable that the dimensions of the first mass parts 21 and 22 and the second mass part 23 are set so as to satisfy the relationship of L ₁ <L ₃ and L ₂ <L ₃ , respectively.

By satisfying the above relationship, L ₁ and L ₂ can be further reduced, the rotation angle of the first mass parts 21 and 22 can be further increased, and the rotation angle of the second mass part 23 is further increased. Can be bigger.

In this case, it is preferable that the maximum rotation angle of the second mass unit 23 is configured to be 20 ° or more.
In addition, by reducing L ₁ and L ₂ in this way, the distance between the first mass parts 21 and 22 and the respective electrodes 32 can be further reduced, and the first mass parts 21 and 22 can be reduced. The AC voltage applied to each electrode 32 can be further reduced.

By these, the low voltage drive of the 1st mass parts 21 and 22 and the vibration (rotation) in the large rotation angle of the 2nd mass part 23 are realizable.
For this reason, when such an actuator 1 is applied to, for example, an optical scanner used in an apparatus such as a laser printer or a scanning confocal laser microscope, the apparatus can be more easily downsized.

As described above, in the present embodiment, L ₁ and L ₂ are set to be substantially equal, but it goes without saying that L ₁ and L ₂ may be different.
By the way, in such a vibration system (two-degree-of-freedom vibration system) composed of the mass parts 21, 22, and 23, the amplitude (deflection angle) of the first mass part 21, 22 and the second mass part 23 is applied. A frequency characteristic as shown in FIG. 8 exists between the frequency of the AC voltage.

That is, the vibration system includes two resonance frequencies fm ₁ [kHz] and fm ₃ [kHz] (however, fm) in which the amplitude of the first mass parts 21 and 22 and the amplitude of the second mass part 23 are increased. ₁ <fm ₃ ) and one anti-resonance frequency fm ₂ [kHz] at which the amplitude of the first mass parts 21 and 22 is substantially zero.

In this vibration system, the frequency F of the AC voltage applied between the first mass parts 21 and 22 and the electrode 32 is set so as to be approximately equal to the lower one of the two resonance frequencies, that is, fm _1. Is preferred. Thereby, the deflection angle (rotation angle) of the second mass unit 23 can be increased while suppressing the amplitude of the first mass units 21 and 22.
In this specification, F [kHz] and fm ₁ [kHz] being substantially equal means that the condition of (fm ₁ −1) ≦ F ≦ (fm ₁ +1) is satisfied.

The average thicknesses of the first mass parts 21 and 22 are each preferably 1 to 1500 μm, and more preferably 10 to 300 μm.
The average thickness of the second mass part 23 is preferably 1 to 1500 μm, and more preferably 10 to 300 μm.
The spring constant _{k 1} of the first elastic connecting portions 25, 1 × and even preferably at ^{10 -4 ~1 × 10 4 Nm /} rad, 1 × ¹⁰ to a -2 ~1 × ¹⁰ 3 Nm / rad More preferably, it is 1 × 10 ⁻¹ to 1 × 10 ² Nm / rad. Thereby, the rotation angle (swing angle) of the second mass unit 23 can be further increased.

On the other hand, the spring constant k ₂ of the second elastic coupling portion 26 is preferably 1 × 10 ⁻⁴ to 1 × 10 ⁴ Nm / rad, and preferably 1 × 10 ⁻² to 1 × 10 ³ Nm / rad. Is more preferably 1 × 10 ⁻¹ to 1 × 10 ² Nm / rad. Thereby, the deflection angle of the 2nd mass part 23 can be enlarged more, suppressing the deflection angle of the 1st mass parts 21 and 22. FIG.

Further, the spring constant _{k 1} of the first elastic connecting portions 25 and _{k 2} the spring constant of the second elastic connecting portions _26, preferably satisfies the k 1> _{k 2} the relationship. Thereby, it is possible to increase the rotation angle (deflection angle) of the second mass unit 23 while suppressing the deflection angle of the first mass units 21 and 22.
Furthermore, the moment of inertia of the first mass portions 21 and 22 and _{J 1,} when the moment of inertia of the second mass 23 has a _{J 2,} and _{J 1} and _{J 2,} the _{J 1} ≦ _{J 2} the relationship It is preferable to satisfy, and it is more preferable to satisfy the relationship of J ₁ <J ₂ . Thereby, it is possible to increase the rotation angle (deflection angle) of the second mass unit 23 while suppressing the deflection angle of the first mass units 21 and 22.

Incidentally, the natural frequency ω ₁ of the first vibration system composed of the first mass parts 21 and 22 and the first elastic coupling parts 25 and 25 is equal to the inertia moment J _{1 of} the first mass parts 21 and 22. And ω ₁ = (k ₁ / J ₁ ) ^1/2 by the spring constant k _{1 of} the first elastic coupling part 25. On the other hand, the natural frequency ω ₂ of the second vibration system composed of the second mass portion 23 and the second elastic coupling portions 26 and 26 is equal to the moment of inertia J _{2 of} the second mass portion 23 and the second According to the spring constant k ₂ of the elastic coupling part 26, ω ₂ = (k ₂ / J ₂ ) ^1/2 is given.

It is preferable that the natural frequency ω ₁ of the first vibration system and the natural frequency ω ₂ of the second vibration system obtained in this way satisfy the relationship ω ₁ > ω ₂ . Thereby, it is possible to increase the rotation angle (deflection angle) of the second mass unit 23 while suppressing the deflection angle of the first mass units 21 and 22.
Such an actuator 1 can be manufactured as follows, for example.
9 to 12 are views (longitudinal sectional views) for explaining the manufacturing method of the actuator of the first embodiment. In the following, for convenience of explanation, the upper side in FIGS. 9 to 12 is referred to as “upper” and the lower side is referred to as “lower”.

[A1] First, as shown in FIG. 9A, a silicon substrate 5 is prepared.
And as shown in FIG.9 (b), a photoresist is apply | coated to both surfaces of the silicon substrate 5, and exposure and image development are performed. Thereby, as shown in FIG. 9B, the resist mask 6 is formed so as to correspond to the shape of the support portion 24.
Next, after etching both surfaces of the silicon substrate 5 through the resist mask 6, the resist mask 6 is removed. As a result, as shown in FIG. 9C, a recess 51 is formed in a region other than the portion corresponding to the support portion 24 (first step). At that time, the etching may be performed simultaneously on both sides of the silicon substrate 5 or may be performed on each side. When the silicon substrate 5 is etched one side at a time, either the etching of one surface on the side where the metal mask 7 described later is formed or the etching of the other surface may be performed.

  As an etching method, for example, one or more of physical etching methods such as plasma etching, reactive ion etching, beam etching, and light-assisted etching, and chemical etching methods such as wet etching are used in combination. be able to. Note that the same method can be used for etching in the following steps.

Next, on one surface of the silicon substrate 5, as shown in FIG. 10A, a metal mask is formed with, for example, aluminum so as to correspond to the shape of the support portion 24 and the mass portions 21, 22, and 23. 7 is formed. Note that a resist mask can be used instead of the metal mask.
Next, the one surface side of the silicon substrate 5 is etched through the metal mask 7 until a portion corresponding to the recess 51 penetrates (second step).

When the metal mask 7 is removed, thereafter, a metal film is formed on the second mass portion 23 to form the light reflecting portion 231.
Here, after etching the silicon substrate 5, the metal mask 7 may be removed or may be left without being removed. When the metal mask 7 is not removed, the metal mask 7 remaining on the second mass portion 23 can be used as the light reflecting portion 231.

Examples of the method for forming a metal film include vacuum plating, sputtering (low temperature sputtering), dry plating methods such as ion plating, wet plating methods such as electrolytic plating and electroless plating, thermal spraying methods, and joining metal foils. . Note that the same method can also be used for forming a metal film in the following steps.
Through the above steps, as shown in FIG. 10B, a structure in which the respective mass portions 21, 22, 23 and the support portion 24 are integrally formed, that is, the base 2 is obtained.

[A2] Next, as shown in FIG. 11A, a silicon substrate 9 for forming the support 3 is prepared. Note that a glass substrate or the like may be used instead of the silicon substrate 9.
Then, a metal mask is formed on one surface of the silicon substrate 9 with, for example, aluminum so as to correspond to a portion excluding the region where the recess 31 is formed.
Next, after etching one surface side of the silicon substrate 9 through the metal mask, the metal mask is removed. Thereby, as shown in FIG.11 (b), the support body 3 in which the recessed part 31 was formed is obtained.
Next, an electrode 32 is formed on the support 3 as shown in FIG.
The electrode 32 is formed by forming a metal film on the surface of the support 3 where the recess 31 is formed, etching the metal film through a mask corresponding to the shape of the electrode 32, and then removing the mask. can do.

  [A3] Next, as shown in FIG. 12A, the base 2 and the support 3 obtained in the step [A1] are joined by, for example, direct joining to obtain a joined body (third Process). Moreover, the light emitting part 43 is attached to the surface on the opposite side to the surface on the joint side with the base 2 among the both surfaces of the support 4. When a glass substrate is used instead of the silicon substrate 9, the base 2 and the support 3 are bonded by anodic bonding.

Next, as shown in FIG. 12 (b), the base 2 of the joined body obtained in the step [A2] and the support 4 (preferably a glass substrate) as the third substrate are joined by, for example, anodic joining or the like. Join. Further, the light receiving portion 33 is attached to the surface of the support 3 opposite to the concave portion 31. Thus, the actuator 1 of the first embodiment is manufactured.
In such a manufacturing method, since the base body 2 is manufactured only from an inexpensive silicon substrate 5 made mainly of silicon without using an expensive SOI substrate, the actuator 1 can be obtained at low cost.

Further, by forming the concave portion 51 (concave portion 29) in the silicon substrate 5 (base 2), the mass portions 21, 22, and 23 are prevented from contacting the support body 3, and the mass portions 21, 22, and 23 are prevented from contacting each other. Therefore, it is possible to reduce the driving voltage and to increase the frequency of each of the mass parts 21, 22, and 23.
Further, by forming the recess 51 (recess 28) in the silicon substrate 5 (base 2), the support 4 is joined to the base 2 without processing, so that the flatness of the surface of the support 4 can be ensured. it can. Thereby, in the support body 4, it is prevented or reduced that incident light and reflected light scatter, etc., As a result, the actuator 1 can obtain a high reflectance.

  Moreover, the formation process of the recessed part 28 and the joining process of the base | substrate 2 and the support body 4 are processes which can be performed more simply than the process of processing the support body 4 by an etching etc. In addition, by setting the depth of the recess 28, the distances between the first mass parts 21, 22 and the second mass part 23 and the support 4 can be easily set to a desired one. Therefore, according to the manufacturing method as described above, the manufacturing process of the actuator 1 can be simplified.

Second Embodiment
Next, based on FIG. 13 thru | or FIG. 15, 2nd Embodiment of the actuator of this invention is described.
13 is a plan view showing the actuator of the second embodiment, FIG. 14 is a cross-sectional view taken along the line AA in FIG. 13, and FIG. 15 is an arrangement of the electrodes, light emitting part, and light receiving part of the actuator shown in FIG. FIG. In the following, for convenience of explanation, the upper side in FIG. 14 is referred to as “upper”, the lower side as “lower”, the right side as “right”, and the left side as “left”.

Hereinafter, the actuator of the second embodiment will be described focusing on the differences from the actuator of the first embodiment, and the description of the same matters will be omitted.
The actuator 1A of the second embodiment is the same as the actuator 1 of the first embodiment, except that the configuration of the second elastic connecting portion and the light shielding portion and the arrangement of the light receiving portion 33 and the light emitting portion 43 are different.

  In the actuator 1A of the present embodiment, as shown in FIG. 13, a light blocking effect is provided by separating the gap 212 from the first mass portion 21 and the gap 222 from the first mass portion 22. A part 242A is provided. In the present embodiment, a light shielding part 241A having light shielding properties is provided with a gap 213 from the first mass part 21 and a gap 223 from the first mass part 22. In the present embodiment, the light shielding portions 241A and 242A are substantially the entire circumference of the pattern including the first mass portions 21 and 22, the first elastic coupling portion 25, the second mass portion 23, and the second elastic coupling portion 26. In other words, they face each other through a gap similar to the gaps 212 and 222.

As shown in FIGS. 14 and 15, the light emitting portion 43 is provided at a portion corresponding to each of the gaps 212 and 222 on the upper surface of the support 4. In addition, light receiving portions 33 are provided at portions corresponding to the gaps 212 and 222 on the lower surface of the support 3.
With this configuration, the light that has passed through the gaps 212 and 222 among the light emitted from the light emitting unit 43 is received by the light receiving unit 33, and the second mass unit 23 is based on the amount of light received. Can be detected.

Here, in the present embodiment, the second elastic connecting portions 26 </ b> A and 26 </ b> A are connected to the first mass portion 21 so that the second mass portion 23 can rotate with respect to the first mass portions 21 and 22. , 22 and the second mass part 23 are connected. Each second elastic connecting portion 26A is composed of one rod-like connecting member.
Also in the actuator 1A according to the present embodiment, the same effect as that of the actuator 1 according to the first embodiment described above can be obtained. That is, a mechanism for detecting the behavior of the second mass portion 23 can be realized easily and inexpensively without performing special processing on the first mass portions 21 and 22 and the second mass portion 23.
In particular, in the present embodiment, a mechanism for detecting the behavior of the second mass portion 26 easily and inexpensively without applying special processing to the first elastic connection portion 25 and the second elastic connection portion 26A. Can be realized. Therefore, the actuator 1A has a higher degree of design freedom, and as a result, can be made at a lower cost.

<Third Embodiment>
Next, a third embodiment of the actuator of the present invention will be described based on FIG.
FIG. 16 is a plan view showing the actuator of the third embodiment. In the following, for convenience of explanation, the front side of the sheet in FIG. 16 is referred to as “upper”, the rear side of the sheet is referred to as “lower”, the right side is referred to as “right”, and the left side is referred to as “left”.
Hereinafter, the actuator of the third embodiment will be described focusing on the differences from the actuator of the first embodiment, and the description of the same matters will be omitted.

The actuator 1B of the third embodiment is the same as the actuator 1 of the first embodiment except that the configuration of the second elastic coupling portion is different.
In the actuator 1B of the present embodiment, as shown in FIG. 16, the second elastic connecting portions 26B and 26B are arranged so that the second mass portion 23 can be rotated with respect to the first mass portions 21 and 22. The 1st mass parts 21 and 22 and the 2nd mass part 23 are connected. Each of the second elastic coupling portions 26B is formed with a plurality of through portions 263A, 263B, and 263C that penetrate in the vertical direction (the thickness direction of the second mass portion 23 in the non-driven state).

The plurality of through portions 263 </ b> A, 263 </ b> B, 263 </ b> C are arranged along the rotation center axis 27.
Further, the plurality of through portions 263A, 263B, 263C are formed so as to have different widths in a direction perpendicular to the rotation center axis 27. Further, the widths of the through portions 263A, 263B, 263C in the direction perpendicular to the rotation center axis 27 are in the order of the through portion 263A, the through portion 263B, and the through portion 263C from the largest to the smallest.

Also in the actuator 1B according to this embodiment, the same effect as that of the actuator 1 according to the first embodiment described above can be obtained. That is, a mechanism for detecting the behavior of the second mass portion 23 can be realized easily and inexpensively without performing special processing on the first mass portions 21 and 22 and the second mass portion 23.
In particular, in the present embodiment, since the light receiving unit 33 is configured to receive light that has passed through the plurality of through portions 263A, 263B, and 263C, only the most suitable place for light reception by the second elastic coupling unit 26 is provided. A penetrating portion can be provided in the light receiving portion 33, and the amount of light received by the light receiving portion 33 can be increased while maintaining the strength of the second elastic connecting portion 26. Thereby, compared with the method of forming a large penetration part, the light quantity change according to the amount of twist of the whole pair of second elastic connection parts 26 is detected while maintaining the strength of the second elastic connection parts 26. Can improve accuracy.

  In addition, since the plurality of penetrating portions 263A, 263B, and 263C are arranged side by side along the rotation center axis 27, the penetrating portion can be formed without changing the torsion axis of the second elastic connecting portion 26. Easy. Further, the twisting amount of the second elastic connecting portion 26 is different at both end portions. For example, the amount of twist of the second elastic connecting portion 26 is maximum near the second mass portion 23 and is minimum at portions close to the first mass portions 21 and 22. A plurality of penetrating portions 263A, 263B, 263C are arranged in parallel to the second elastic connecting portion 26 along the rotation center axis 27, and light passing through the plurality of penetrating portions 263A, 263B, 263C is received by the light receiving portion 33. By receiving light at a time, unevenness in the amount of light received by the light receiving unit 33 due to the position of the penetrating part can be reduced, and the detection accuracy of the behavior of the second mass unit 25 can be increased.

Further, when a plurality of through portions 263A, 263B, 263C having different widths in the direction perpendicular to the rotation center axis 27 are provided as in the present embodiment, the amount of light received by the light receiving portion 33 is stepwise. Therefore, a specific behavior (for example, a rotation angle) of the second mass unit 23 can be detected more accurately. In this case, it is preferable that the light emitting unit 43 and the light receiving unit 33 are provided with light receiving elements at positions corresponding to the through portions 263A, 263B, and 263C in a plan view in FIG.
The actuator 1 as described above can be suitably applied to, for example, a laser printer, a barcode reader, an optical scanner such as a scanning confocal laser microscope, an imaging display, and the like.

As mentioned above, although the actuator of this invention was demonstrated based on each embodiment of illustration, this invention is not limited to these.
For example, the actuator of the present invention may be combined with any two or more configurations of the first to third embodiments.
In the actuator of the present invention, the configuration of each part can be replaced with an arbitrary configuration that exhibits the same function, and an arbitrary configuration can be added.

  In the above-described embodiment, an actuator using a torsional vibrator having a two-degree-of-freedom vibration system has been described, but the present invention can also be applied to an actuator of a vibration system other than the two-degree-of-freedom vibration system. For example, in the above-described embodiment, the first elastic connecting portion is omitted, the first mass portion is fixed to the support portion, and the second mass connecting portion and the support portion are directly connected by the second elastic connecting portion. It is good also as a form which connected. That is, the present invention can also be applied to an actuator using a torsional vibrator having a one-degree-of-freedom vibration system.

  In the above-described embodiment, the second elastic connecting portion is formed with the penetrating portion. However, the first elastic connecting portion may be formed with the penetrating portion.

Further, the shape, position, size, and the like of the penetrating part depend on the degree of torsional deformation (the behavior of the second mass part and the mass part) of the first elastic coupling part and the second elastic coupling part. If it changes, it is not limited to the thing of embodiment mentioned above.
For example, the penetration direction of the penetration part is not limited to that of the above-described embodiment, and may be, for example, a direction parallel to the plate surface of the second mass part in the non-driven state.

Moreover, the light shielding part should just be provided in the path | route vicinity of the light from a light emission part to a light-receiving part.
In the above-described second embodiment, the light emitting unit and the light receiving unit include the first mass units 21, 22, the first elastic coupling unit 25, and the first mass unit 23 in a plan view of the second mass unit 23 in the non-driven state. The second mass based on the amount of light received by the light receiving portion, regardless of the position formed in the gap formed along substantially the entire circumference of the pattern composed of the second mass portion 23 and the second elastic coupling portion 26. The behavior of the part can be detected.

In the above-described embodiment, the configuration in which the light reflecting portion 231 is provided on the surface of the second mass portion 23 on the support 33 side has been described. However, for example, in the configuration provided on the opposite surface. There may be a configuration provided on both sides. It goes without saying that the effects of the present invention can be obtained even if the light reflecting portion is omitted.
In the above-described embodiment, when the rigidity of the support portion 24 of the base 2 is relatively high, at least one support portion of the supports 3 and 4 can be omitted. In this case, the light emitting unit and the light receiving unit may be fixed to the base 2 or may be fixed to a member different from the base 2.

  In the above-described embodiment, the first mass portions 21 and 22 are rotated by electrostatic driving, and the second mass portion 23 is rotated accordingly, that is, driving means for driving the movable portion. However, the driving means is not limited to this, and other driving methods such as piezoelectric driving can also be adopted. In addition to the parallel plate type as described above, the driving means using electrostatic driving may have other forms such as those using comb-like electrodes.

It is a top view which shows 1st Embodiment of the actuator of this invention. It is the sectional view on the AA line in FIG. It is the BB sectional view taken on the line in FIG. It is a top view which shows arrangement | positioning with the electrode of the actuator shown in FIG. 1, a light emission part, and a light-receiving part. It is a block diagram which shows schematic structure of the control system in the actuator shown in FIG. It is a figure for demonstrating the behavior detection of the 2nd mass part in the actuator shown in FIG. It is a figure which shows an example of the drive voltage in the actuator shown in FIG. It is a graph which shows the relationship between the frequency of a drive voltage when the alternating voltage is used as a drive voltage, and the amplitude of a 1st mass part and a 2nd mass part. It is a figure for demonstrating the manufacturing method of the actuator of 1st Embodiment. It is a figure for demonstrating the manufacturing method of the actuator of 1st Embodiment. It is a figure for demonstrating the manufacturing method of the actuator of 1st Embodiment. It is a figure for demonstrating the manufacturing method of the actuator of 1st Embodiment. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the actuator of this invention. It is AA sectional view taken on the line in FIG. It is a top view which shows arrangement | positioning with the electrode of the actuator shown in FIG. 13, a light emission part, and a light-receiving part. It is a top view which shows 3rd Embodiment of the actuator of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1A, 1B ... Actuator 13 ... Current supply circuit 14 ... Control circuit 141 ... CPU 142 ... AD converter circuit 143 ... ROM 144 ... RAM 2 ... Base | substrate 21, 22 ... 1st mass part 211, 221... End portions 212, 213, 222, 223, 264, 265... Gap 23... Second mass portion 231 ..light reflecting portion 232... End portion 24 .. support portions 241, 242, 241A 242A..light-shielding part 25..first elastic coupling part 26, 26B..second elastic coupling part 261, 262 ... bar-like coupling member 263, 263A, 263B, 263C..penetrating part 27..rotation Central axes 28, 29 ....... Recess 3 ... Support 31 ... Recess 32 ... Electrode 33..Light receiving part 4 ... Support 43..Light emitting part 5 ... Silicon substrate 51 ... Recess 6 ... Registrar Click 7 ...... metal mask 9 ...... silicon substrate _{L 1, L 2, L 3} ...... distance

Claims (16)

Part by mass;
A support part for supporting the mass part;
An elastic connecting part that connects the mass part and the support part so that the mass part is rotatable with respect to the support part;
Driving means for generating a driving force for rotating the mass section;
Behavior detecting means for detecting the behavior of the mass part,
An actuator configured to actuate the driving unit based on a detection result of the behavior detecting unit and rotate the mass unit while twisting and deforming the elastic coupling unit;
The elastic connecting portion is formed with a penetrating portion penetrating in a direction perpendicular to the rotation center axis of the mass portion,
The behavior detection unit includes a light emitting unit that emits light toward the penetrating part and a light receiving unit that receives light that has passed through the penetrating part, and is based on the amount of light received by the light receiving unit. The actuator is configured to detect the behavior of the mass part. A first mass part;
A support part for supporting the first mass part;
A first elastic connecting portion that connects the first mass portion and the support portion so that the first mass portion is rotatable with respect to the support portion;
A second mass part;
A second elastic connecting portion for connecting the first mass portion and the second mass portion so that the second mass portion is rotatable with respect to the first mass portion;
Driving means for generating a driving force for rotating the first mass unit;
Behavior detecting means for detecting the behavior of the second mass part,
Based on the detection result of the behavior detecting means, the driving means is operated to rotate the first mass portion while twisting and deforming the first elastic connecting portion. Accordingly, the second elastic connecting portion is rotated. An actuator configured to rotate the second mass portion while twisting and deforming the portion,
The first elastic connecting portion and / or the second elastic connecting portion includes a through portion penetrating in a direction perpendicular to the rotation center axis of the first mass portion and / or the second mass portion. Formed,
The behavior detection unit includes a light emitting unit that emits light toward the penetrating part and a light receiving unit that receives light that has passed through the penetrating part, and is based on the amount of light received by the light receiving unit. The actuator is configured to detect the behavior of the second mass part.   The actuator according to claim 2, wherein the second mass portion has a plate shape, and the penetration portion penetrates in a thickness direction of the second mass portion in a non-driven state.   4. The actuator according to claim 2, wherein a plurality of the through portions are provided, and the light receiving portion is configured to receive light that has passed through the plurality of through portions.   The actuator according to claim 4, wherein the plurality of through portions are arranged in parallel along the rotation center axis.   The actuator according to claim 2, wherein the penetrating portion is formed in the second elastic coupling portion.   The actuator according to claim 2, wherein the penetrating portion has a longitudinal shape extending along the rotation center axis.   The first elastic connecting portion and / or the second elastic connecting portion is constituted by two rod-like connecting members that are opposed to each other with an interval through the rotation center axis, The actuator according to any one of claims 2 to 7, which is a space between two rod-like connecting members.   8. The light-shielding part according to claim 2, wherein the light-shielding part has a light-shielding property and is provided at a distance from the first elastic coupling part and / or the second elastic coupling part in which the penetrating part is formed. Actuator.   The actuator according to claim 2, wherein the light receiving unit also receives light that has passed through the gap. B / A is 1 × 10 ⁻³ to 1 where A is the length in the penetration direction of the penetration part and B is the width of the penetration part in the direction perpendicular to the rotation center axis. The actuator according to claim 2.   12. The incident direction of the light to the penetrating portion is substantially the same as the penetrating direction of the penetrating portion in a non-driven state of the first mass portion and the second mass portion. Actuator.   A base on which the first mass part, the support part, the first elastic connecting part, the second mass part, and the second elastic connecting part are formed; and a support that supports the base. The actuator according to claim 2, wherein the light emitting unit and / or the light receiving unit is provided on the support.   The actuator according to claim 2, wherein a light reflecting portion having light reflectivity is provided on the second mass portion. Part by mass;
A support part for supporting the mass part;
An elastic connecting part that connects the mass part and the support part so that the mass part is rotatable with respect to the support part;
Driving means for generating a driving force for rotating the mass section;
Behavior detecting means for detecting the behavior of the mass part,
An actuator configured to actuate the driving unit based on a detection result of the behavior detecting unit and rotate the mass unit while twisting and deforming the elastic coupling unit;
A light-shielding part provided with a gap between at least one of the mass part and the elastic coupling part, and having a light-shielding property;
The behavior detecting means includes a light emitting unit that emits light toward the gap, and a light receiving unit that receives the light that has passed through the gap, and based on the amount of light received by the light receiving unit, An actuator configured to detect a behavior of a mass part. A first mass part;
A support part for supporting the first mass part;
A first elastic connecting portion that connects the first mass portion and the support portion so that the first mass portion is rotatable with respect to the support portion;
A second mass part;
A second elastic connecting portion for connecting the first mass portion and the second mass portion so that the second mass portion is rotatable with respect to the first mass portion;
Driving means for generating a driving force for rotating the first mass unit;
Behavior detecting means for detecting the behavior of the second mass part,
Based on the detection result of the behavior detecting means, the driving means is operated to rotate the first mass portion while twisting and deforming the first elastic connecting portion. Accordingly, the second elastic connecting portion is rotated. An actuator configured to rotate the second mass portion while twisting and deforming the portion,
There is provided a light-shielding part having a light-shielding property and provided with a gap with respect to at least one of the first mass part, the first elastic coupling part, the second mass part, and the second elastic coupling part. And
The behavior detecting means includes a light emitting unit that emits light toward the gap, and a light receiving unit that receives the light that has passed through the gap, and based on the amount of light received by the light receiving unit, An actuator configured to detect a behavior of a mass part.

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