WO2013076844A1

WO2013076844A1 - Actuator

Info

Publication number: WO2013076844A1
Application number: PCT/JP2011/077068
Authority: WO
Inventors: 健二郎藤本; 山村　雄一
Original assignee: パイオニア株式会社; パイオニア・マイクロ・テクノロジー株式会社
Priority date: 2011-11-24
Filing date: 2011-11-24
Publication date: 2013-05-30

Abstract

An actuator (101) is provided with a movable section (120), a supporting section (110) surrounding the movable section, a torsion bar (130) for connecting the movable section and the supporting section so that the movable section is able to swing, and a processing circuit (140) formed on the movable section for processing related to the rocking motion of the movable section. The torsion bar comprises (i) a first bar part (131) having wiring (150) formed to establish a connection to the processing circuit and (ii) a second bar part (132) devoid of wiring. The maximum value of stress applied to the first bar part when the movable section rocks is smaller than the maximum value of stress applied to the second bar part when the movable section rocks.

Description

Actuator

The present invention relates to a technical field of an actuator such as a MEMS scanner that drives a movable part provided with, for example, a mirror.

For example, in various technical fields such as displays, printing apparatuses, precision measurement, precision processing, and information recording / reproduction, research on MEMS (Micro Electro Mechanical System) devices manufactured by semiconductor process technology has been actively promoted. As such a MEMS device, a MEMS scanner used for scanning a laser beam is known. Such a MEMS scanner includes a movable plate, a frame-shaped support frame that surrounds the movable plate, and a torsion bar that pivotally supports the movable plate so as to be swingable with respect to the support frame.

Here, in a general MEMS scanner, a mirror is formed at the center of the surface of the movable plate, and a driving coil is formed around the mirror. A pair of permanent magnets for generating a static magnetic field for the drive coil is disposed on the support frame. According to the MEMS scanner configured as described above, an electromagnetic driving force (Lorentz force) is generated in the driving coil by supplying a control current to the driving coil. Accordingly, the movable plate on which the driving coil is formed is moved.

As a prior art disclosing such a MEMS scanner, Patent Documents 1 to 5 are given as examples.

JP 2005-517990 Gazette JP 2010-39496 A Special table 2007-525025 gazette Special table 2007-522529 JP 2007-295780 A

By the way, a driving control current is generally supplied to a driving coil formed on the movable plate from a power source formed outside the movable plate via a wiring formed on the torsion bar. . However, when the torsion bar is twisted as the movable plate is moved, stress due to the twist is also applied to the wiring formed on the torsion bar. As a result, there arises a technical problem that the wiring is disconnected due to the stress.

The above-mentioned technical problem is that the movable plate (or any movable part) is not limited to the MEMS scanner that swings the movable plate (or any movable part) so as to rotate. The same can occur for a MSMS actuator that is swung.

Furthermore, the technical problem described above is connected not only to the wiring formed on the torsion bar so as to be connected to the drive coil formed on the movable plate, but also to an arbitrary processing circuit formed on the movable plate. The same may occur for the wiring formed on the torsion bar.

The present invention has been made in view of, for example, the conventional problems described above. For example, the movable portion supported by the torsion bar can be swung while suitably preventing disconnection of the wiring formed on the torsion bar. It is an object to provide an actuator.

In order to solve the above problems, the actuator includes a movable part, a support part surrounding the movable part, a torsion bar that connects the movable part and the support part so that the movable part can swing, And a processing circuit that performs a process related to the swinging of the movable part, and the torsion bar includes: (i) a first bar portion in which wiring connected to the processing circuit is formed; (Ii) a second bar portion in which the wiring is not formed, and the maximum value of stress applied to the first bar portion when the movable portion swings is the maximum value when the movable portion swings. It is smaller than the maximum value of stress applied to the 2 bar portion.

The operation and other advantages of the present invention will be clarified from the embodiments described below.

It is a top view which shows an example of a structure of the actuator of 1st Example. It is a top view which shows the detail of a structure of the torsion bar with which the actuator of 1st Example is provided. It is a top view which shows an example of a structure of the actuator of 2nd Example. It is a top view which shows an example of a structure of the actuator of 3rd Example. It is a top view which shows an example of a structure of the actuator of 4th Example. It is a top view which shows an example of a structure of the actuator of 5th Example. It is a top view which shows an example of a structure of the actuator of 6th Example. It is a top view which shows an example of a structure of the actuator of 7th Example.

Hereinafter, embodiments of the actuator will be described in order.

The actuator of the present embodiment is formed in the movable part, a support part surrounding the movable part, a torsion bar connecting the movable part and the support part so that the movable part can swing, and the movable part. And a processing circuit that performs processing related to the swinging of the movable part, and the torsion bar includes: (i) a first bar portion in which wiring connected to the processing circuit is formed; and (ii) A second bar portion on which the wiring is not formed, and a maximum value of stress applied to the first bar portion when the movable portion swings is the second bar portion when the movable portion swings. It is smaller than the maximum value of applied stress.

¡According to the actuator of this embodiment, the movable part suspended by the torsion bar swings. For example, the movable portion may be swung so as to rotate about the direction in which the torsion bar extends as a central axis, or along the direction in which the torsion bar extends or in the direction intersecting with the direction in which the torsion bar extends. You may swing to move along.

At this time, the torsion bar may directly connect the movable part and the support part. Alternatively, the torsion bar may indirectly connect the movable part and the support part (in other words, with an arbitrary member interposed therebetween).

A processing circuit is formed in the movable part. At this time, the processing circuit may be formed on the surface of the movable part, or may be formed so as to be embedded in the movable part. The processing circuit is, for example, a circuit that performs an arbitrary process related to the swinging of the movable part. As such a processing circuit, for example, a drive coil for generating a Lorentz force for swinging the movable part, a detection circuit for detecting a swinging mode (for example, inclination, swing amount, etc.) of the movable part, etc. Is an example. The processing circuit is supplied with a control current or a control signal related to the swaying of the movable part from a power source or a signal source provided in the actuator or prepared outside the actuator via a wiring described later.

In this embodiment, the torsion bar includes a first bar portion and a second bar portion.

The first bar portion is a bar portion in which the maximum value of stress applied when the movable portion swings (for example, when the movable portion swings by a predetermined amount) becomes relatively small. In other words, the maximum value of the stress applied to the first bar portion when the movable portion swings (for example, when the movable portion swings by a predetermined amount) is greater than the maximum stress applied to the second bar portion. This is the smaller bar part. Further, the first bar portion is a bar portion where wiring is formed.

On the other hand, the second bar portion is a bar portion in which the maximum value of stress applied when the movable portion swings (for example, when the movable portion swings by a predetermined amount) becomes relatively small. In other words, in the second bar portion, the maximum value of stress applied when the movable portion swings (for example, when the movable portion swings by a predetermined amount) is greater than the maximum value of stress applied to the first bar portion. This is the bar part that grows. Furthermore, the second bar portion is a bar portion where no wiring is formed.

Note that the first bar portion and the second bar portion have a single torsion bar with or without the wiring described above and the maximum value of stress applied when the movable portion is swung (or with respect to the swing of the movable portion, which will be described later). It is preferable to have a shape, structure, or arrangement position that can be distinguished from the viewpoint of contribution, total length, width, thickness, and the like. However, the first bar portion and the second bar portion have a single torsion bar with or without the wiring described above and the maximum value of stress applied when the movable portion is swung (or with respect to the swing of the movable portion, which will be described later). As long as it can be distinguished from the viewpoint of contribution, total length, width, thickness, etc., it can be said that it may have any form. For example, the first bar portion and the second bar portion may be physically separated from each other, or may be partially overlapped (for example, integrated as described later). May be)

The torsion bar may further include a bar portion other than the first bar portion and the second bar portion. For example, in the torsion bar, the third bar portion where the maximum value of the stress applied when the movable part swings is relatively small (for example, smaller than the maximum value of the stress applied to the first bar portion) and no wiring is formed. And a fourth bar portion in which the maximum value of stress applied when the movable portion is swung is relatively large (for example, larger than the maximum value of stress applied to the second bar portion) and the wiring is formed. You may go out. Even an actuator including such a third bar portion or a fourth bar portion is included in the scope of the actuator of the present embodiment as long as it includes the first bar portion and the second bar portion. it is obvious.

According to such an actuator of the present embodiment, when the movable part swings, not only the first bar part where the wiring is formed but also the second bar part where the wiring is not formed also has the movable part. The torsion bar bends or twists so as to swing. At this time, when the movable portion swings, it is preferable that the second bar portion mainly defines the bending or twisting operation of the torsion bar, but the first bar portion mainly controls the bending or twisting operation of the torsion bar. Alternatively, both the first bar portion and the second bar portion may equally regulate the torsion bar bending or twisting motion. Here, as described above, the stress applied to the second bar portion due to bending or twisting of the torsion bar becomes relatively large. However, since the wiring is not formed in the second bar portion, the torsion bar is not distinguished (in other words, separated) into the first bar portion and the second bar portion (that is, wiring is performed on one torsion bar). And the one torsion bar defines the torsion bar bending or twisting action), the wire is relatively less likely to break due to torsion bar bending or twisting.

On the other hand, even when the movable part swings, the stress applied to the first bar portion becomes relatively small. Therefore, the torsion bar is not distinguished from the first bar portion and the second bar portion (that is, the wiring is formed on one torsion bar and the one torsion bar defines the bending or twisting operation of the torsion bar. Compared with the actuator, the wiring formed in the first bar portion is relatively less likely to break due to bending or twisting of the torsion bar.

As a result, according to the actuator of this embodiment, it is possible to move the movable part supported by the torsion bar while suitably preventing disconnection of the wiring formed on the torsion bar.

It should be noted that a countermeasure for preventing the disconnection of the wiring by devising the material of the wiring or the like (for example, forming the wiring using a material having a high resistance to disconnection) can be considered. However, since the material of the wiring is restricted, it may lead to restrictions on the design of the actuator including the wiring. However, according to the present embodiment, disconnection of the wiring can be prevented without restricting the material of the wiring.

Furthermore, a countermeasure for suppressing the stress applied to the wiring formed on the torsion bar by increasing the entire length of the torsion bar without distinguishing between the first bar portion and the second bar portion can be considered. However, if the entire length of the torsion bar is simply increased in order to give priority to the suppression of stress applied to the wiring, there is a possibility that the swinging of the movable part, which is the original function of the torsion bar, may be restricted. However, according to this embodiment, since the torsion bar is distinguished from the first bar portion and the second bar portion, the swinging of the movable portion, which is the original function of the torsion bar, is suppressed while suppressing the stress applied to the wiring. Is hardly affected.

In another aspect of the actuator of the present embodiment, the total length of the first bar portion is longer than the total length of the second bar portion.

According to this aspect, the maximum value of the stress applied to the first bar portion can be relatively reduced by relatively increasing the overall length of the first bar portion. Similarly, the maximum value of the stress applied to the second bar portion can be relatively increased by relatively shortening the overall length of the second bar portion. That is, by making the total length of the first bar portion longer than the total length of the second bar portion, the maximum value of stress applied to the first bar portion can be made smaller than the maximum value of stress applied to the second bar portion. .

In the aspect of the actuator in which the total length of the first bar portion is longer than the total length of the second bar portion as described above, the first bar portion extends in the direction in which the torsion bar extends from the support portion toward the movable portion. You may comprise so that it may have the shape bent at least once in the direction which crosses.

If comprised in this way, by making the shape of at least one part of a 1st bar part into the bent shape, the full length of a 1st bar part is made comparatively long (that is, rather than the full length of a 2nd bar part). Can be longer).

In addition, the shape where the shape of the first bar portion is bent means, for example, that the first bar portion is once directed in a different direction with respect to the direction in which the torsion bar extends from the support portion toward the movable portion. Examples include a shape that expands so as to return to the original direction after expansion, a shape that expands while the first bar portion meanders, a shape that expands while the first bar portion is bent in a zigzag shape, and the like.

Further, in this case, it is preferable that the second bar portion has a shape that is not bent in a direction intersecting with a direction in which the torsion bar extends so as to go from the support portion to the movable portion. For example, the second bar portion has a shape that passes through the shortest path from the support portion toward the movable portion (or from the connection point between the support portion and the torsion bar to the connection point between the movable portion and the torsion bar). You may do it. However, the second bar portion may have a shape that is bent in a direction intersecting with a direction in which the torsion bar extends so as to go from the support portion to the movable portion. Similarly, the second bar portion has a shape that does not pass through the shortest path from the support portion toward the movable portion (or from the connection point between the support portion and the torsion bar to the connection point between the movable portion and the torsion bar). You may have.

In the aspect of the actuator in which the total length of the first bar portion is longer than the total length of the second bar portion as described above, the first bar portion extends in the direction in which the torsion bar extends from the support portion toward the movable portion. May be configured to have a shape that is folded at least once in the opposite direction.

If comprised in this way, by making the shape of at least one part of the 1st bar part into the shape where it turned up, the full length of the 1st bar part is made relatively long (that is, from the full length of the 2nd bar part) Can also be long).

Note that the shape of the first bar portion being folded back means, for example, that the first bar portion extending in the direction in which the torsion bar extends from the support portion toward the movable portion is An example is a shape that is bent (that is, folded) at an angle of 90 degrees or more with respect to the direction.

In this case, the second bar portion preferably has a shape that is not folded back in the direction opposite to the direction in which the torsion bar extends so as to go from the support portion to the movable portion. For example, the second bar portion has a shape that passes through the shortest path from the support portion toward the movable portion (or from the connection point between the support portion and the torsion bar to the connection point between the movable portion and the torsion bar). You may do it. However, the second bar portion may have a shape folded back in a direction opposite to the direction in which the torsion bar extends so as to go from the support portion to the movable portion. Similarly, the second bar portion has a shape that does not pass through the shortest path from the support portion toward the movable portion (or from the connection point between the support portion and the torsion bar to the connection point between the movable portion and the torsion bar). You may have.

As described above, in the aspect of the actuator in which the total length of the first bar portion is longer than the total length of the second bar portion, the movable portion swings so as to rotate along a predetermined rotation axis, At least a part of the second bar portion is formed to extend in a direction different from the direction along the rotation axis, and the second bar portion is formed to extend in a direction along the rotation axis. May be.

If comprised in this way, it has the shape extended in the direction along a rotating shaft by making the shape of a 1st bar part the shape extended in a direction different from the direction along a rotating shaft. Compared to the total length of the two bar portions, the total length of the first bar portions can be made relatively long.

In another aspect of the actuator of the present embodiment, the first bar portion is thinner than the second bar portion.

According to this aspect, the maximum value of the stress applied to the first bar portion can be relatively reduced by relatively reducing the thickness of the first bar portion. Similarly, the maximum value of the stress applied to the second bar portion can be relatively increased by relatively increasing the thickness of the second bar portion. That is, the maximum value of the stress applied to the first bar portion can be made smaller than the maximum value of the stress applied to the second bar portion by making the thickness of the first bar portion thinner than the thickness of the second bar portion. it can.

In another aspect of the actuator of the present embodiment, the contribution of the second bar part to the swing of the movable part is greater than the contribution of the first bar part to the swing of the movable part.

According to this aspect, the second bar portion mainly defines the swinging aspect of the movable part. That is, the influence of the first bar portion on the swinging mode of the movable portion is smaller than the influence of the second bar portion. In other words, the second bar portion mainly defines the bending or twisting motion of the torsion bar. That is, the influence of the first bar portion on the bending or twisting operation of the torsion bar is smaller than the influence of the second bar portion.

As a result, a relatively large stress is applied to the second bar portion because it mainly regulates the bending or twisting motion of the torsion bar that causes the movable portion to move farther. However, since no wiring is formed in the second bar portion, there is a relatively low possibility that the wiring is disconnected due to bending or twisting of the torsion bar. On the other hand, since the bending or twisting operation of the torsion bar that swings the movable part is not mainly defined, the stress applied to the first bar portion causes the bending or twisting operation of the torsion bar that swings the movable part. It becomes smaller than the stress applied to the second bar portion which is mainly defined. Therefore, there is a relatively low possibility that the wiring formed in the first bar portion will be disconnected due to bending or twisting of the torsion bar.

In consideration of the fact that the movable part swings due to the bending or twisting of the torsion bar, the “contribution to the swinging of the moving part” is the degree (or percentage) that defines the bending or twisting operation of the torsion bar. ).

In another aspect of the actuator of the present embodiment, the width of the first bar portion in the direction in which the first bar portion extends is greater than the width of the second bar portion in the direction in which the second bar portion extends. .

According to this aspect, since the wiring is formed, the second bar portion does not have such a restriction with respect to the first bar portion, which has a restriction that the predetermined width determined by the width of the wiring cannot be supplemented. . For this reason, the second bar portion can have an ideal thin rod-like shape as a so-called torsion bar, and as a result, it is possible to mainly define the mode of swinging of the movable portion. In other words, the second bar portion can mainly define the bending or twisting motion of the torsion bar. As a result, a relatively large stress is applied to the second bar portion because it mainly defines the bending or twisting motion of the torsion bar that causes the movable portion to swing. However, since no wiring is formed in the second bar portion, there is a relatively low possibility that the wiring is disconnected due to bending or twisting of the torsion bar.

In another aspect of the actuator of the present embodiment, the first bar portion is physically separated from the second bar portion.

According to this aspect, since the first bar portion where the wiring is formed and the second bar portion where the wiring is formed can be physically separated, the disconnection of the wiring can be more suitably prevented.

In another aspect of the actuator of the present embodiment, the first bar portion and the second bar portion intersect each other at least once, and at least a part of the first bar portion in the intersecting portion is the first bar portion. The two bar portions are formed integrally with at least a part.

In this aspect, since the first bar portion and the second bar portion are integrated at least once (in other words, joined), the first bar portion alone is bent or twisted (or resonated). It can prevent suitably. That is, it is possible to suitably prevent a situation in which the swinging mode of the movable part is adversely affected by the bending or twisting (or resonance) of the first bar portion alone.

In another aspect of the actuator of the present embodiment, the movable portion swings so as to rotate along a predetermined rotation axis, and the first bar portion is formed at a position different from the rotation axis, The second bar portion is formed on the rotation shaft.

In this aspect, since the second bar portion is formed on the rotating shaft, it is possible to mainly define the bending or twisting operation of the torsion bar. As a result, the maximum value of stress applied to the second bar portion can be relatively increased. On the other hand, since the first bar portion is not formed on the rotation axis, the first bar portion rarely mainly defines the bending or twisting operation of the torsion bar. As a result, the maximum value of stress applied to the first bar portion can be relatively reduced. That is, the maximum value of stress applied to the first bar portion can be made smaller than the maximum value of stress applied to the second bar portion.

In another aspect of the actuator of the present embodiment, the torsion bars are a pair of torsion bars extending so as to sandwich the movable part from two opposite sides inside the support part, and the pair of torsion bars At least one includes the first bar portion and the second bar portion.

In this aspect, one of the pair of torsion bars sandwiching the movable portion includes both the first bar portion and the second bar portion. That is, in the actuator in which the torsion bars are arranged on both sides of the movable part, both the first bar part and the second bar part are arranged on one side of the movable part.

In another aspect of the actuator of the present embodiment, the movable portion swings so as to rotate along a predetermined rotation axis, and at least one of the first bar portion and the second bar portion is the rotation shaft. Have a symmetrical shape.

According to this aspect, the swinging of the movable part (that is, rotation along the rotation axis) is performed relatively smoothly. Therefore, the torsion bar can be distinguished from the first bar portion and the second bar portion without greatly affecting the normal swing of the movable portion.

Such an operation and other advantages of the present embodiment will be clarified from examples described below.

As described above, according to the actuator of the present embodiment, the movable portion, the support portion, the torsion bar, and the drive coil are provided, and the torsion bar is formed with the first bar portion where the wiring is formed and the wiring. The maximum value of the stress applied to the first bar portion is smaller than the maximum value of the stress applied to the second bar portion. Therefore, it is possible to move the movable part supported by the torsion bar while suitably preventing disconnection of the wiring formed on the torsion bar.

Hereinafter, examples will be described with reference to the drawings.

(1) First Embodiment Hereinafter, the actuator 101 of the first embodiment will be described with reference to FIG. FIG. 1 is a plan view showing an example of the configuration of the actuator 101 of the first embodiment. FIG. 2 is a detailed enlarged view showing details of the shapes of the torsion bar 130 and the wiring 140 included in the actuator 101 of the first embodiment.

As shown in FIG. 1, the actuator 101 according to the first embodiment is a planar electromagnetic drive actuator (that is, a MEMS scanner) used for, for example, laser beam scanning. The actuator 101 includes a support part 110, a movable part 120, a pair of torsion bars 130, and a pair of permanent magnets 160.

The support portion 110, the movable portion 120, and the pair of torsion bars 130 are integrally formed from a nonmagnetic substrate such as a silicon substrate, for example. That is, the support part 110, the movable part 120, and the pair of torsion bars 130 are formed by forming a gap by removing a part of a nonmagnetic substrate such as a silicon substrate. A MEMS process is preferably used as the formation process at this time. Instead of the silicon substrate, the support portion 110, the movable portion 120, and the pair of torsion bars 130 may be integrally formed from an arbitrary elastic material.

The support part 110 has a frame shape surrounding the movable part 120, and is located on both sides of the movable part 120 (in other words, sandwiching the movable part from both sides of the movable part 120) by a pair of torsion bars 130. The movable part 120 is connected.

The movable part 120 is pivotally supported on the support part 110 by a pair of torsion bars 130 so as to be swingable. A mirror (not shown) that reflects the laser light is formed on the surface of the movable portion 120. A drive coil 140 is further formed on the surface of the movable portion 120. However, the drive coil 140 may be formed inside the movable part 120.

The drive coil 140 is, for example, a coil that extends so as to surround a mirror (not shown) formed on the surface of the movable part 120. The drive coil 140 may be formed using, for example, a material having relatively high conductivity (for example, gold or copper). The drive coil 140 may be formed using a semiconductor manufacturing process such as a plating process or a sputtering method. Alternatively, the drive coil 140 may be embedded in a silicon substrate for forming the support part 110, the movable part 120, and the pair of torsion bars 130 using an implant method. In FIG. 1, the outer shape of the drive coil 140 is simplified for the sake of easy viewing, but in actuality, the drive coil 140 is formed on the surface of the movable portion 120. It is constituted by one or a plurality of windings.

The drive coil 140 includes a power terminal 170 formed on the support 110 and a wiring 150 for electrically connecting the power terminal 170 and the drive coil 140, and is formed on the torsion bar 130. A control current is supplied from the power supply via the wiring 150. The control current is a control current for swinging the movable portion 120, and is typically an alternating current including a signal component having a frequency synchronized with the frequency at which the movable portion 120 swings. The power source may be a power source provided in the actuator 101 itself, or a power source prepared outside the actuator 101.

The pair of torsion bars 130 connect the movable portion 120 and the support portion 110 so that the movable portion 120 can swing with respect to the support portion 110. Due to the elasticity of the pair of torsion bars 130, the movable portion 120 swings so as to rotate about an axis along the direction in which the pair of torsion bars 130 extends as a central axis (in other words, a rotation axis). That is, the movable unit 120 swings so as to rotate around the central axis with the axis along the left-right direction in FIG. 1 as the central axis.

The pair of permanent magnets 160 are attached to the outside of the support part 110. The pair of permanent magnets 160 preferably have their magnetic poles appropriately set so that a predetermined static magnetic field can be applied to the drive coil 140. Note that a yoke may be added to the pair of permanent magnets 160 in order to increase the strength of the static magnetic field.

When the actuator 101 according to the first embodiment operates (specifically, the movable unit 120 swings), first, from the power source to the drive coil 140 via the power terminal 170 and the wiring 150. In contrast, a control current is supplied. On the other hand, a static magnetic field is applied to the drive coil 140 by a pair of permanent magnets 160. Therefore, a force (that is, a Lorentz force) due to an electromagnetic interaction between the static magnetic field applied from the pair of permanent magnets 160 and the control current supplied to the drive coil 140 is generated in the drive coil 140. As a result, the movable part 120 in which the drive coil 140 is formed swings due to the Lorentz force resulting from the electromagnetic interaction between the static magnetic field applied from the pair of permanent magnets 160 and the control current supplied to the drive coil 140. To do. That is, the movable part 120 swings so as to rotate about the axis along the left and right direction in FIG.

Particularly in the first embodiment, each of the pair of torsion bars 130 includes a first bar portion 131 and a second bar portion 132. The first bar portion 131 and the second bar portion 132 are preferably distinguished from two viewpoints described with reference to FIG. 2 below. 2A is an enlarged plan view showing details of the shape of the torsion bar 130, and FIG. 2B is an enlarged plan view showing details of the shape of the first bar portion 131 included in the torsion bar 130. FIG. 2B is an enlarged plan view showing details of the shape of the second bar portion 132 included in the torsion bar 130. In FIG. 2A to FIG. 2C, a wiring 150 indicated by a dotted line is also shown for easy understanding of the shape of the torsion bar 130. 1 and 2 illustrate an example in which both of the pair of torsion bars 130 include the first bar portion 131 and the second bar portion 132, but only one of the pair of torsion bars 130 is included. The first bar portion 131 and the second bar portion 132 may be included. That is, either one of the pair of torsion bars 130 may not include the first bar portion 131 and the second bar portion 132.

First, as a first viewpoint, the first bar portion 131 and the second bar portion 132 are distinguished by the maximum value of stress applied when the movable portion 120 swings. Specifically, the maximum value of stress applied to the first bar portion 131 when the movable portion 120 swings by a predetermined amount is the stress applied to the second bar portion 132 when the movable portion 120 swings by a predetermined amount. Is less than the maximum value. In other words, the maximum value of the stress applied to the second bar portion 132 when the movable portion 120 swings by a predetermined amount is the maximum value of the stress applied to the first bar portion 131 when the movable portion 120 swings by a predetermined amount. Greater than the value.

In order to make the maximum value of the stress applied to the first bar portion 131 different from the maximum value of the stress applied to the second bar portion 132, in the first embodiment, from FIG. 2A to FIG. 2C. As shown, the total length of the first bar portion 131 (specifically, the total length in the direction in which the first bar portion 131 extends) and the total length of the second bar portion 132 (specifically, the second bar portion 132 is The total length in the extending direction) is different. More specifically, as shown in FIGS. 2A to 2C, the overall length of the first bar portion 131 is longer than the overall length of the second bar portion 132. In other words, as shown in FIGS. 2A to 2C, the total length of the second bar portion 132 is shorter than the total length of the first bar portion 131. That is, the torsion bar 130 of the first embodiment includes a first bar portion 131 having a relatively long overall length and a second bar portion 132 having a relatively short overall length.

In this way, in order to make the total length of the first bar portion 131 different from the total length of the second bar portion 132, in the first embodiment, the shape of the first bar portion 131 and the shape of the second bar portion 132 are changed. It is different.

Specifically, in the first embodiment, the second bar portion 132 has a direction in which the torsion bar 130 extends from the support portion 110 toward the movable portion 120 (specifically, the left and right directions in FIGS. 1 and 2). ). At this time, the second bar portion 132 extends along only the direction in which the torsion bar 130 extends from the support unit 110 toward the movable unit 120 (specifically, the left and right directions in FIGS. 1 and 2). May be. On the other hand, the first bar portion 131 may extend not only in the direction in which the torsion bar 130 extends from the support part 110 toward the movable part 120 but also in a direction bent from the direction. More specifically, the first bar portion 131 extends in a direction (in the example of FIGS. 1 and 2, which is orthogonal to the direction in which the torsion bar 130 extends from the support portion 110 toward the movable portion 120. You may do it.

The direction in which the torsion bar 130 extends from the support part 110 toward the movable part 120 substantially coincides with the direction of the rotation axis of the movable part 120. Therefore, from the viewpoint of the rotation axis of the movable part 120, it can be said that the second bar portion 132 extends in a direction along the rotation axis of the movable part 120. On the other hand, it can be said that the first bar portion 131 extends in a direction different from the direction along the rotation axis of the movable portion 120.

Further, the first bar portion 131 not only has a direction from the support portion 110 toward the movable portion 120 (a direction from the left side to the right side in FIGS. 1 and 2) but also a direction opposite to the direction (FIGS. 1 and 2). 2 in the direction from the right side to the left side). Alternatively, the first bar portion 131 is not only the direction from the support portion 110 toward the movable portion 120 (the direction from the left side to the right side in FIGS. 1 and 2), but also the direction folded back from the direction (the direction). , And a direction folded at an angle of at least 90 degrees and extending in the direction from the right side to the left side in FIGS. 1 and 2.

However, it goes without saying that the specific method for making the total length of the first bar portion 131 different from the total length of the second bar portion 132 is not limited to the above-described example. That is, the first bar portion 131 and the second bar portion 132 may be extended in other manners other than the example described above, so that the total length of the first bar portion 131 and the total length of the second bar portion 132 may be different. Needless to say.

As described above, the maximum value of the stress applied to the first bar portion 131 is different from the maximum value of the stress applied to the second bar portion 132 (when the movable portion 120 is swung by a predetermined amount, the first bar portion The stress applied to 131 is smaller than the stress applied to the second bar portion 132 when the movable portion 120 is swung by the same predetermined amount), so that the second bar portion is moved when the movable portion 120 is swung. Stress can be concentrated at 132.

At this time, the degree to which the first bar portion 131 contributes (in other words, contributes) to the sway of the movable part 120 is different from the degree to which the second bar part 132 contributes to the sway of the movable part 120. It is preferable to become a thing. Specifically, it is preferable that the degree to which the first bar portion 131 contributes to the swing of the movable portion 120 is smaller than the degree to which the second bar portion 132 contributes to the swing of the movable portion 120. . In other words, it is preferable that the degree to which the second bar portion 132 contributes to the swing of the movable portion 120 is greater than the degree to which the first bar portion 131 contributes to the swing of the movable portion 120. In this case, the movable portion 120 swings mainly due to the bending or twisting of the second bar portion 132.

Note that, from the viewpoint of relatively increasing the contribution of the movable unit 120 to the swing, it is preferable that at least the second bar portion 132 is located on the rotation axis of the movable unit 120. However, the second bar portion 132 may not be located on the rotation axis of the movable portion 120. Even when the second bar portion 132 is not positioned on the rotation axis of the movable portion 120, the degree to which the second bar portion 132 contributes to the swing of the movable portion 120 is determined with respect to the swing of the movable portion 120. Thus, the degree to which the first bar portion 131 contributes can be increased. In addition, it is preferable that at least a part of the first bar portion 131 is located on the rotation axis of the movable portion 120. However, the first bar portion 131 may not be located on the rotation axis of the movable portion 120.

Further, from the viewpoint of relatively increasing the degree of contribution of the movable part 120 to the sway, it is preferable that the second bar portion 132 is as hard as possible while satisfying the conditions or constraints described above or described later. In particular, it is preferable that the second bar portion 132 is soft with respect to the rotation direction of the movable portion 120 but hard with respect to other directions. Further, it is preferable that the first bar portion 131 is as soft as possible while satisfying the conditions or restrictions described above or described later. However, the relative hardness relationship between the first bar portion 131 and the second bar portion 132 is not always determined uniformly, and even if the first bar portion 131 is harder than the second bar portion 132. Alternatively, the second bar portion 132 may be harder than the first bar portion 131. In addition, it is preferable that the 1st bar part 131 is also hard with respect to the other direction like the 2nd bar part 132, although it is soft with respect to the rotation direction of the movable part 120. As a result, the first bar portion 131 and the second bar portion 132 as a whole have a hardness that can act appropriately as a single torsion bar 130 with respect to the sway of the movable portion 120. Is preferred.

However, the degree to which the first bar portion 131 contributes to the swing of the movable portion 120 may be the same as the degree to which the second bar portion 132 contributes to the swing of the movable portion 120. Alternatively, the degree to which the second bar portion 132 contributes to the swaying of the movable part 120 may be smaller than the degree to which the first bar part 131 contributes to the swaying of the movable part 120.

In the above description, in order to make the maximum value of the stress applied to the first bar portion 131 different from the maximum value of the stress applied to the second bar portion 132, the total length of the first bar portion 131 is set to the second bar. The total length of the portion 132 is different. However, in order to make the maximum value of the stress applied to the first bar portion 131 different from the maximum value of the stress applied to the second bar portion 132, the total length of each of the first bar portion 131 and the second bar portion 132 is increased. In addition to or instead of being different, the other characteristics (for example, material, material, manufacturing method, etc.) of the first bar portion 131 and the second bar portion 132 may be different.

Alternatively, the maximum value of stress applied to the first bar portion 131 is different from the maximum value of stress applied to the second bar portion 132, or the maximum value of stress applied to the first bar portion 131 and the second bar portion. In addition to or instead of making the maximum stress applied to 132 different, as shown in FIGS. 2 (a) to 2 (c), the width of at least a part of the first bar portion 131 (specifically, Specifically, the width along the direction in which the first bar portion 131 extends and the width of at least a part of the second bar portion 132 (specifically, the width along the direction in which the second bar portion 132 extends). ) May be different. More specifically, as shown in FIGS. 2A to 2C, the width of the first bar portion 131 may be larger than the width of the second bar portion 132. In other words, as shown in FIGS. 2A to 2C, the width of the second bar portion 132 may be narrower than the width of the first bar portion 131. That is, the torsion bar 130 of the first embodiment may include a first bar portion 131 having a relatively large width and a second bar portion 132 having a relatively small width.

Alternatively, the maximum value of stress applied to the first bar portion 131 is different from the maximum value of stress applied to the second bar portion 132, or the maximum value of stress applied to the first bar portion 131 and the second bar portion. In addition to or instead of making the maximum value of the stress applied to 132 different, the thickness of at least a portion of the first bar portion 131 (specifically, the thickness along the thickness direction of the actuator 101). The thickness of at least a part of the second bar portion 132 may be different. More specifically, for example, the thickness of the first bar portion 131 may be smaller than the thickness of the second bar portion 132. In other words, the thickness of the second bar portion 132 may be narrower than the thickness of the first bar portion 131. That is, the torsion bar 130 of the first embodiment may include a first bar portion 131 having a relatively small thickness and a second bar portion 132 having a relatively large thickness.

Alternatively, the maximum value of stress applied to the first bar portion 131 is different from the maximum value of stress applied to the second bar portion 132, or the maximum value of stress applied to the first bar portion 131 and the second bar portion. In addition to or instead of making the maximum stress applied to 132 different, other characteristics of the first bar portion 131 and the second bar portion 132 (for example, materials, materials, manufacturing methods, etc.) By making them different, the degree to which the first bar portion 131 contributes to the swing of the movable part 120 and the degree to which the second bar part 132 contributes to the swing of the movable part 120 may be different. Good. In this case, the first bar portion 131 and the second bar portion 132 contribute to the sway of the movable part 120 instead of being distinguished by the maximum value of the stress applied when the movable part 120 sways. It is distinguished by the degree to do.

Furthermore, as a second viewpoint, the first bar portion 131 and the second bar portion 132 are distinguished by whether or not the wiring 150 connected to the drive coil 140 is formed thereon. Specifically, a wiring 150 is formed in the first bar portion 131. On the other hand, the wiring 150 is not formed in the second bar portion 132.

In addition to or instead of the wiring 150 connected to the drive coil 140, an arbitrary wiring connected to an arbitrary circuit existing on the movable unit 120 and supplied with an effective signal related to the operation of the arbitrary circuit is formed. The first bar portion 131 and the second bar portion 132 may be distinguished depending on whether or not they are set. In this case, an arbitrary wiring is formed on the first bar portion 131, while an arbitrary wiring is not formed on the second bar portion 132.

However, so-called dummy wiring (for example, (i) a signal to be supplied is not used effectively for the operation of the actuator 101, or (ii) even if it is disconnected, it has no effect on the normal operation of the actuator 101. May be formed on the second bar portion 132.

As described above, according to the actuator 101 of the first embodiment, when the movable part 120 swings, the torsion so that the first bar part 131 and the second bar part 132 swing the movable part 120 is performed. The bar 130 bends or twists. At this time, the stress applied to the relatively hard second bar portion 132 due to bending or twisting of the torsion bar 130 (in other words, the swing of the movable portion 120) becomes relatively large. However, since the wiring 150 is not formed in the second bar portion 132, the torsion bar is not separated into the first bar portion and the second bar portion (that is, the wiring is formed on one torsion bar and Compared to the actuator of the comparative example (the one torsion bar defines the swing of the movable part), the possibility that the wiring 150 is disconnected due to the bending or twisting of the torsion bar 130 is relatively low.

On the other hand, even when the movable part 120 swings, the stress applied to the first bar portion 131 remains relatively small. In other words, even when the movable part 120 swings, the stress applied to the first bar portion 131 is smaller than the stress applied to the second bar portion 132. Therefore, the torsion bar is not separated into the first bar portion and the second bar portion (that is, the wiring is formed on one torsion bar and the one torsion bar defines the swing of the movable portion). Compared to the above, the wiring 150 formed in the first bar portion 131 is relatively less likely to be disconnected due to the torsion bar 130 being bent or twisted.

As a result, according to the actuator 101 of the first embodiment, it is possible to move the movable part 120 supported by the torsion bar 130 while suitably preventing the wire 150 formed on the torsion bar 130 from being disconnected.

Note that, according to the actuator 101 of the first embodiment, the first bar portion 131 and the second bar portion 132 intersect at least once. In addition, it is preferable that the 1st bar part 131 and the 2nd bar part 132 are integrated in the location which mutually crosses (in other words, coupling | bonding or integration). For example, in the actuator 101 shown in FIGS. 1 and 2, since the first bar portion 131 intersects with the first bar portion 131 at both ends of each second bar portion 132, the first bar portion 131 and the second bar portion 132 are rotated six times. Crossed. That is, in the actuator 101 shown in FIGS. 1 and 2, the first bar portion 131 and the second bar portion 132 are integrated at six locations. As described above, the first bar portion 131 and the second bar portion 132 intersect at least once (in other words, at least one place is integrated), so that the first bar portion 131 resonates independently. There is almost no end. Therefore, even if the torsion bar 130 is separated into the first bar portion 131 and the second bar portion 132, the influence on the swing of the movable portion 120 is reduced or almost eliminated.

Further, the torsion bar 130 may further include a bar portion other than the first bar portion 131 and the second bar portion 132. For example, the torsion bar 130 may further include a third bar portion that is relatively soft and the wiring 150 is not formed, and a fourth bar portion that is relatively hard and the wiring 150 is formed.

(2) Second Embodiment Next, an actuator 102 according to a second embodiment will be described with reference to FIG. FIG. 3 is a plan view showing an example of the configuration of the actuator 102 of the second embodiment. Note that the same reference numerals are assigned to the same components as those provided in the actuator 101 of the first embodiment, and the detailed description thereof is omitted.

As shown in FIG. 3, the actuator 102 of the second embodiment is physically separated from the entire first bar portion 131 and the entire second bar portion 132 as compared to the actuator 101 of the first embodiment. Are different (in other words, separated). In other words, in the actuator 102 of the second embodiment, the first bar portion 131 and the second bar portion 132 are supported independently of each other without crossing each other (in other words, never integrated). The portion 110 extends toward the movable portion 120.

Even in the actuator 102 of the second embodiment, various effects that can be enjoyed by the actuator 101 of the first embodiment can be suitably enjoyed. In addition, since the first bar portion 131 and the second bar portion 132 are completely separated, the stress when the movable part 120 swings can be more concentrated on the second bar portion 132. As a result, disconnection of the wiring 150 formed on the first bar portion 131 can be more suitably prevented.

(3) Third Embodiment Next, the actuator 103 of the third embodiment will be described with reference to FIG. FIG. 4 is a plan view showing an example of the configuration of the actuator 103 of the third embodiment. Note that the same reference numerals are assigned to the same components as those provided in the actuator 101 of the first embodiment, and the detailed description thereof is omitted.

As shown in FIG. 4, the actuator 103 of the third embodiment has a movable portion in a state where the first bar portion 131 and the second bar portion 132 are physically separated compared to the actuator 101 of the first embodiment. It is different in that it is connected to 120. In the actuator 101 of the first embodiment, the first bar portion 131 and the second bar portion 132 are temporarily separated on the way from the support portion 110 to the movable portion 120, but the movable portion 120. The first bar portion 131 and the second bar portion 132 cannot be distinguished from each other in the step of connecting to the first bar portion. In the actuator 103 of the third embodiment, the first bar portion 131 and the second bar portion 132 are physically integrated (or the first bar portion 131 and the second bar portion 132 are distinguished from each other). The actuator 101 is the same as the actuator 101 of the first embodiment in that it is connected to the support portion 110 in a state in which the actuator cannot be operated.

Even in the actuator 103 of the third embodiment, various effects that can be enjoyed by the actuator 101 of the first embodiment can be suitably enjoyed.

(4) Fourth Embodiment Next, an actuator 104 according to a fourth embodiment will be described with reference to FIG. FIG. 5 is a plan view showing an example of the configuration of the actuator 104 of the fourth embodiment. Note that the same reference numerals are assigned to the same components as those provided in the actuator 101 of the first embodiment, and the detailed description thereof is omitted.

As shown in FIG. 5, the actuator 104 of the fourth embodiment has a support portion in a state where the first bar portion 131 and the second bar portion 132 are physically separated as compared with the actuator 101 of the first embodiment. 110 is different in that it is connected to 110. In the actuator 101 of the first embodiment, the first bar portion 131 and the second bar portion 132 are temporarily separated on the way from the support portion 110 to the movable portion 120, but the support portion 110. The first bar portion 131 and the second bar portion 132 cannot be distinguished from each other in the step of connecting to the first bar portion. In the actuator 104 of the fourth embodiment, the first bar portion 131 and the second bar portion 132 are physically integrated (or the first bar portion 131 and the second bar portion 132 are distinguished from each other. The actuator 101 is the same as the actuator 101 of the first embodiment in that it is connected to the movable part 120 in a state in which the actuator 101 cannot be operated.

Even in the actuator 104 of the fourth embodiment, various effects that can be enjoyed by the actuator 101 of the first embodiment can be suitably enjoyed.

(5) Fifth Embodiment Next, an actuator 105 according to a fifth embodiment will be described with reference to FIG. FIG. 6 is a plan view showing an example of the configuration of the actuator 105 of the fifth embodiment. Note that the same reference numerals are assigned to the same components as those provided in the actuator 101 of the first embodiment, and the detailed description thereof is omitted.

As shown in FIG. 6, the actuator 105 of the fifth embodiment is folded back when the first bar portion 131 is viewed from the support portion 110 toward the movable portion 120 as compared to the actuator 101 of the first embodiment. It is different in that it does not extend in the other direction (in other words, it is not folded). In the actuator 101 of the first embodiment, at least a part of the first bar portion 131 extends in a folded direction when viewed from the support portion 110 toward the movable portion 120.

Even in the actuator 105 of the fifth embodiment, various effects that can be enjoyed by the actuator 101 of the first embodiment can be suitably enjoyed.

(6) Sixth Embodiment Next, an actuator 106 according to a sixth embodiment will be described with reference to FIG. FIG. 7 is a plan view showing an example of the configuration of the actuator 106 of the sixth embodiment. Note that the same reference numerals are assigned to the same components as those provided in the actuator 101 of the first embodiment, and the detailed description thereof is omitted.

As shown in FIG. 7, the actuator 106 of the sixth embodiment is different from the actuator 101 of the first embodiment in that the movable portion 622 can be driven in two axes. Specifically, the actuator 106 of the sixth embodiment includes a support part 110, a movable frame 621, a movable part 622, a pair of torsion bars 130, a pair of torsion bars 630, and a pair of permanent magnets 160. I have.

The support part 110, the movable frame 621, the movable part 622, the pair of torsion bars 130, and the pair of torsion bars 630 are integrally formed from a nonmagnetic substrate such as a silicon substrate, for example. In other words, the support portion 110, the movable frame 621, the movable portion 622, the pair of torsion bars 130, and the pair of torsion bars 630 have a gap formed by removing a part of a nonmagnetic substrate such as a silicon substrate. It is formed with. A MEMS process is preferably used as the formation process at this time. Instead of the silicon substrate, the support part 110, the movable frame 621, the movable part 622, the pair of torsion bars 130, and the pair of torsion bars 630 may be integrally formed from an arbitrary elastic material.

The support part 110 has a frame shape surrounding the movable frame 621 and is located on both sides of the movable frame 621 (in other words, sandwiching the movable frame 621 from both sides of the movable frame 621). Is connected to the movable frame 621.

The movable frame 621 has a frame shape surrounding the movable portion 622, and is pivotally supported on the support portion 110 by a pair of torsion bars 130 so as to be swingable. A drive coil 140 is formed on the surface of the movable frame 120. However, the drive coil 140 may be formed inside the movable frame 621.

The drive coil 140 includes a power terminal 170 formed on the support 110 and a wiring 150 for electrically connecting the power terminal 170 and the drive coil 140, and is formed on the torsion bar 130. A control current is supplied from the power supply via the wiring 150. The control current is a control current for swinging the movable frame 621, and is typically an alternating current including a signal component having a frequency synchronized with the frequency at which the movable frame 621 swings.

The movable part 622 is pivotally supported on the movable frame part 621 by a pair of torsion bars 630 so as to be swingable. A mirror (not shown) that reflects the laser light is formed on the surface of the movable portion 622.

Although not shown in FIG. 7 for the sake of easy viewing, the driving coil is also formed on the movable portion 622 in the same manner as the movable portion 120 included in the actuator 101 of the first embodiment. It is preferable.

The pair of torsion bars 130 connect the movable frame 621 and the support unit 110 so that the movable frame 621 can swing with respect to the support unit 110. Due to the elasticity of the pair of torsion bars 130, the movable frame 621 swings so as to rotate about an axis along the direction in which the pair of torsion bars 130 extends as a central axis (in other words, a rotation axis). That is, the movable frame 621 swings so as to rotate around the central axis with the axis along the left and right directions in FIG. 7 as the central axis. At this time, the movable portion 622 is connected to the movable frame 621 via a pair of torsion bars 630. Accordingly, as the movable frame 621 swings, the movable portion 622 substantially swings so as to rotate around the central axis with the axis along the left-right direction in FIG. 7 as the central axis. .

The pair of torsion bars 630 connect the movable part 622 and the movable frame 621 so that the movable part 622 can swing with respect to the movable frame 621. Due to the elasticity of the pair of torsion bars 630, the movable portion 622 swings so as to rotate about the axis along the direction in which the pair of torsion bars 630 extends as a central axis (in other words, a rotation axis). That is, the movable portion 622 swings so as to rotate around the central axis with the axis along the vertical direction in FIG. 7 as the central axis.

When the actuator 106 according to the sixth embodiment operates (specifically, the movable portion 120 swings), first, from the power source to the drive coil 140 via the power terminal 170 and the wiring 150. In contrast, a control current is supplied. At this time, the control current supplied to the drive coil 140 causes the signal for causing the movable frame 621 to swing (specifically, a signal synchronized with the swing period of the movable frame 621) and the movable unit 622. It is preferable that the current be superimposed on a signal to be moved (specifically, a signal synchronized with the swing period of the movable portion 622). On the other hand, a static magnetic field is applied to the drive coil 140 by a pair of permanent magnets 160. Therefore, a force (that is, a Lorentz force) due to an electromagnetic interaction between the static magnetic field applied from the pair of permanent magnets 160 and the control current supplied to the drive coil 140 is generated in the drive coil 140. As a result, the movable frame 621 in which the drive coil 140 is formed swings due to the Lorentz force resulting from the electromagnetic interaction between the static magnetic field applied from the pair of permanent magnets 160 and the control current supplied to the drive coil 140. To do. That is, the movable frame 621 swings so as to rotate about the axis along the left and right directions in FIG. At this time, the movable portion 622 is connected to the movable frame 621 via a pair of torsion bars 630. Accordingly, as the movable frame 621 swings, the movable portion 622 substantially swings so as to rotate around the central axis with the axis along the left-right direction in FIG. 7 as the central axis. .

In addition, the Lorentz force resulting from the electromagnetic interaction between the static magnetic field applied from the pair of permanent magnets 160 and the control current supplied to the drive coil 140 is transmitted to the movable part 622 as an inertial force. As a result, the movable part 622 swings so as to rotate about the axis along the vertical direction in FIG. 7 as the central axis.

Thus, according to the actuator 106 of the sixth embodiment, the movable portion 622 is driven in two axes.

In the sixth embodiment, the biaxial drive of the movable portion 622 is performed by swinging the movable frame 621 using the Lorentz force itself and swinging the movable portion 622 using the Lorentz force as an inertial force. ing. However, a drive coil for generating a Lorentz force that causes the movable part 622 to swing may be formed on the movable part 622. In this case, the pair of torsion bars 630 (and the movable frame 621, the pair of torsion bars 130, and the support unit 110) are connected to the drive coil on the movable unit 622 from the power terminal 170 on the support unit 110. It is preferable that a connecting wiring is formed. In this case, it is preferable that at least one of the pair of torsion bars 630 includes a first bar portion 131 and a second bar portion 132, similarly to the torsion bar 130. Further, in this case, it is preferable that a pair of permanent magnets for applying a static magnetic field to the drive coil on the movable portion 622 is attached to the outside of the support portion 110.

Even in the actuator 106 of the sixth embodiment, various effects that can be enjoyed by the actuator 101 of the first embodiment can be suitably enjoyed.

(7) Seventh Embodiment Next, an actuator 107 according to a seventh embodiment will be described with reference to FIG. FIG. 8 is a plan view showing an example of the configuration of the actuator 107 of the seventh embodiment. Note that the same reference numerals are assigned to the same components as those provided in the actuator 101 of the first embodiment, and the detailed description thereof is omitted.

As shown in FIG. 8, in the actuator 107 of the seventh embodiment, the first bar portion 131 has a line-symmetric relationship with respect to the rotation axis of the movable portion 120 as compared to the actuator 101 of the first embodiment. It is different in that it does. That is, in the actuator 107 of the seventh embodiment, the first bar portion 131 branches in the left-right direction along the rotation axis of the movable portion 120, and the branch shape in the left-right direction becomes a virtual center line on the rotation axis. It is symmetrical with respect to the line.

Even with the actuator 107 of the seventh embodiment, various effects that can be enjoyed by the actuator 101 of the first embodiment can be suitably enjoyed. In addition, since the first bar portion 131 is axisymmetric with respect to the rotation axis, the presence of the first bar portion 131 has little or no significant adverse effect on the normal swing of the movable portion 120. Therefore, the smoother swing of the movable part 120 can be realized.

In addition, you may combine suitably a part of each structure demonstrated in 1st Example-7th Example. For example, the physical separation of the first bar portion 131 and the second bar portion 132 described in the second embodiment may be combined with the biaxial drive described in the sixth embodiment. Even in this case, the actuator obtained by appropriately combining a part of the configurations described in the first to seventh embodiments can suitably enjoy the various effects described above.

In the above description, the description is advanced focusing on the MEMS scanner in which the movable unit 120 rotates about the axis along the direction in which the torsion bar 130 extends. However, the various configurations described above may be applied to any actuator, not limited to the MEMS scanner. For example, the various configurations described above may be applied to the MEMS actuator that moves so that the movable unit 120 moves in parallel with the movement of the torsion bar 130. Even in this case, the above-described various effects are favorably enjoyed.

The present invention is not limited to the above-described embodiments, and can be appropriately changed without departing from the spirit or concept of the invention which can be read from the claims and the entire specification. It is included in the technical scope of the invention.

DESCRIPTION OF SYMBOLS 110 Support part 120 Movable part 130 Torsion bar 131 1st bar part 132 2nd bar part 140 Drive coil 150 Wiring 160 Permanent magnet

Claims

Moving parts;
A support part surrounding the movable part;
A torsion bar that connects the movable part and the support part so that the movable part can swing;
A processing circuit that is formed in the movable part and performs processing related to the swinging of the movable part,
The torsion bar includes (i) a first bar portion where a wiring connected to the processing circuit is formed, and (ii) a second bar portion where the wiring is not formed,
The maximum value of stress applied to the first bar part when the movable part swings is smaller than the maximum value of stress applied to the second bar part when the movable part swings. Actuator.
2. The actuator according to claim 1, wherein a total length of the first bar portion is longer than a total length of the second bar portion.
The first bar portion has a shape bent at least once in a direction intersecting a direction in which the torsion bar extends so as to go from the support portion to the movable portion. The actuator described.
The first bar portion has a shape folded at least once in a direction opposite to a direction in which the torsion bar extends so as to go from the support portion to the movable portion. The actuator according to claim 2.
The movable part swings so as to rotate along a predetermined rotation axis,
At least a portion of the first bar portion is formed to extend in a direction different from the direction along the rotation axis;
The actuator according to claim 2, wherein the second bar portion is formed to extend in a direction along the rotation axis.
The actuator according to claim 1, wherein the first bar portion is thinner than the second bar portion.
2. The actuator according to claim 1, wherein the contribution degree of the second bar part to the swing of the movable part is larger than the contribution degree of the first bar part to the swing of the movable part.
The width of the first bar portion in the direction in which the first bar portion extends is greater than the width of the second bar portion in the direction in which the second bar portion extends. Actuator.
2. The actuator according to claim 1, wherein the first bar portion is physically separated from the second bar portion.
The first bar portion and the second bar portion intersect each other at least once, and at least a part of the first bar portion is integrated with at least a part of the second bar portion at the intersecting portion. The actuator according to claim 1, wherein the actuator is formed.
The movable part swings so as to rotate along a predetermined rotation axis,
The first bar portion is formed at a position different from the rotation axis,
The actuator according to claim 1, wherein the second bar portion is formed on the rotation shaft.
The torsion bars are a pair of torsion bars extending so as to sandwich the movable part from two opposite sides inside the support part,
2. The actuator according to claim 1, wherein at least one of the pair of torsion bars includes the first bar portion and the second bar portion.
The movable part swings so as to rotate along a predetermined rotation axis,
2. The actuator according to claim 1, wherein at least one of the first bar portion and the second bar portion has a symmetrical shape with respect to the rotation axis.