Actuator Device

By introducing a curved deformation part in the connection area, the stress uneven problem caused by temperature changes is solved, the vibration frequency change of the main part is suppressed, and the stable driving characteristics under temperature changes are achieved.

JP7672925B2Active Publication Date: 2025-05-08HAMAMATSU PHOTONICS KK

Patent Information

Application Number
JP2021142427
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Priority Date
2021-05-12
Filing Date
2021-09-01
Publication Date
2025-05-08
Estimated Expiration
2041-09-01

AI Technical Summary

Technical Problem

When the temperature changes, the expansion or contraction of the supporting structure causes uneven forces to the connecting part and the main body part, resulting in changes in vibration frequency and affecting the driving characteristics.

Method used

By introducing a curved deformation portion in the connection area, the local deformation of the curved deformation portion can absorb unnecessary stress when the temperature changes, thereby suppressing the change in vibration frequency of the main body part.

Benefits of technology

The driving characteristics are effectively stabilized, the vibration frequency changes caused by temperature changes are avoided, and stable operation under temperature changes are ensured.

✦ Generated by Eureka AI based on patent content.

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Patent Text Reader

Abstract

To provide an actuator device capable of stably obtaining desired drive characteristics even if, for example, an environment temperature is changed.SOLUTION: A metal board 3 supported by a wiring board includes: a movable part; a first extension part 33; a first connection part 35 for connecting the first extension part 33 to the movable part; and a first connection part 37 connected to the first extension part 33. The first connection part 37 includes: a first fixed area 371 fixed to the wiring board; and a first connection area 372 connected to the first extension part 33 and the first fixed area 371. The first connection area 372 includes a first bent part 372c. The first bent part 372c includes a first outer edge P1 in the movable part side and a second outer edge P2 in a side opposite to the movable part, and each of the first outer edge P1 and the second outer edge P2 is bent to the movable part side when viewed from a Z-axis direction.SELECTED DRAWING: Figure 6
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Description

[Technical field]

[0001] The present invention relates to an actuator device. [Background technology]

[0002] There is known an actuator device including a support, a metal substrate supported by the support, and a vibration element disposed in a main body of the metal substrate. In such an actuator device, the metal substrate further includes a movable portion, a pair of extending portions extending from the main body such that the movable portion is located therebetween, a pair of connecting portions connecting the pair of extending portions and the movable portion, and a pair of connecting portions connected to the pair of extending portions, and a portion of each connecting portion may be fixed to the support (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-187292 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the actuator device described above, when the support expands or contracts due to changes in environmental temperature, unnecessary stress acts on each connecting portion and main body portion through a portion of each connection portion fixed to the support, and as a result, the resonant frequency of the metal substrate may change, and the desired driving characteristics may not be obtained.

[0005] An object of the present invention is to provide an actuator device that can stably obtain desired drive characteristics even if, for example, the environmental temperature changes. [Means for solving the problem]

[0006] The vibration element is provided with a support, a metal substrate supported by the support, and a vibration element arranged on a main body portion of the metal substrate, the metal substrate further having a movable portion, a first extension portion and a second extension portion extending from the main body portion so that the movable portion is located therebetween, a first connecting portion connecting the first extension portion and the movable portion, a second connecting portion connecting the second extension portion and the movable portion, a first connection portion connected to the first extension portion, a second connection portion connected to the second extension portion, and a third connection portion connected to the main body portion, the first connection portion including a first fixing region fixed to the support and a first connection region connected to the first extension portion and the first fixing region, the second connection portion including a second fixing region fixed to the support, and a second connection region connected to the second extension portion and the second fixing region, the third connection portion includes a third fixing region fixed to the support and a third connection region connected to the main body portion and the third fixing region, the first connection region includes a first curved portion, the second connection region includes a second curved portion, the first curved portion has a first outer edge on the movable part side and a second outer edge opposite the movable part, the second curved portion has a third outer edge on the movable part side and a fourth outer edge opposite the movable part, each of the first outer edge and the second outer edge is bent towards the movable part side when viewed from the thickness direction of the metal substrate, and each of the third outer edge and the fourth outer edge is bent towards the movable part side when viewed from the thickness direction of the metal substrate.

[0007] In this actuator device, even if the support expands or contracts due to, for example, a change in the environmental temperature, the first and second curved portions in the first and second connection regions deform, so that unnecessary stress is less likely to act on the first and second connecting portions and the main body portion via the first and second fixing regions fixed to the support, and unnecessary stress is less likely to act on the main body portion via the third fixing region fixed to the support, thereby suppressing changes in the resonance frequency of the metal substrate. Therefore, with this actuator device, the desired drive characteristics can be stably obtained even if, for example, the environmental temperature changes.

[0008] In the actuator device of the present invention, the first connection region may further include a first portion extending linearly from the first extension portion, and the second connection region may further include a second portion extending linearly from the second extension portion, the first portion being connected to the first curved portion, and the second portion being connected to the second curved portion. This makes it possible to suppress the influence of deformation of the first curved portion on the connection portion between the first extension portion and the first coupling portion. Similarly, it is possible to suppress the influence of deformation of the second curved portion on the connection portion between the second extension portion and the second coupling portion.

[0009] In the actuator device of the present invention, the first connection region may further include a third portion extending linearly from the first fixing region, and the second connection region may further include a fourth portion extending linearly from the second fixing region, the third portion having a positional relationship intersecting with the first portion and connected to the first curved portion, and the fourth portion having a positional relationship intersecting with the second portion and connected to the second curved portion. This makes it possible to locally deform the first curved portion and the second curved portion in the first connection region and the second connection region when the support expands or contracts due to a change in environmental temperature, for example.

[0010] In the actuator device of the present invention, when viewed from the thickness direction of the metal substrate, the angle that the third portion forms with respect to the direction in which the main body portion and the movable portion are arranged may be greater than 0 degrees and less than or equal to 90 degrees, and when viewed from the thickness direction of the metal substrate, the angle that the fourth portion forms with respect to the direction in which the main body portion and the movable portion are arranged may be greater than 0 degrees and less than or equal to 90 degrees. This ensures that the first and second curved portions in the first and second connection regions can be deformed reliably when the support expands or contracts due to, for example, a change in environmental temperature.

[0011] In the actuator device of the present invention, when viewed in the thickness direction of the metal substrate, the first outer edge and the second outer edge may each be curved so as to be convex on the side opposite the movable part, and when viewed in the thickness direction of the metal substrate, the third outer edge and the fourth outer edge may each be curved so as to be convex on the side opposite the movable part. This reduces stress concentration in the first curved portion and the second curved portion when the support expands or contracts due to changes in environmental temperature, for example, and therefore prevents damage to the first curved portion and the second curved portion.

[0012] In the actuator device of the present invention, the first fixing region and the second fixing region may be spaced apart from each other across a region located on the opposite side of the movable part from the main body part in the direction in which the main body part and the movable part are arranged. This makes it possible to reduce the risk of stray light being generated when light is irradiated onto the movable part, for example, by reflection of the light by the first fixing region or the second fixing region.

[0013] In the actuator device of the present invention, the metal substrate may further include a first intermediate portion connected to the third fixing region and the first fixing region, and a second intermediate portion connected to the third fixing region and the second fixing region, thereby improving the handleability of the metal substrate during manufacture of the actuator device. Effect of the Invention

[0014] According to the present invention, it is possible to provide an actuator device that can stably obtain desired drive characteristics even if, for example, the environmental temperature changes. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a perspective view of an actuator device according to an embodiment. [Diagram 2] FIG. 2 is a plan view of the actuator device shown in FIG. [Diagram 3] 2 is a plan view of a portion of the wiring board and the metal board shown in FIG. 1. [Figure 4]2 is a plan view of a portion of the wiring board and the metal board shown in FIG. 1. [Diagram 5] 2 is a plan view of a portion of the wiring board and the metal board shown in FIG. 1. [Figure 6] 2 is a plan view of a portion of the metal substrate shown in FIG. 1. [Figure 7] 2 is a plan view of a portion of the metal substrate shown in FIG. 1. [Figure 8] 13 is a plan view of a portion of a wiring board and a metal board according to a first modified example. FIG. [Figure 9] 13 is a plan view of a portion of a wiring board and a metal board according to a second modified example. FIG. [Figure 10] FIG. 13 is a plan view of a metal substrate according to a third modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In each drawing, the same or corresponding parts are denoted by the same reference numerals, and duplicated explanations will be omitted. [Structure of the actuator device]

[0017] As shown in FIG. 1 and FIG. 2, the actuator device 1 includes a wiring board (support) 2, a metal substrate 3, a first adhesive member 4, an optical function unit 5 having an optical surface 51, a driving piezoelectric element (vibration element) 6, a detecting piezoelectric element 7, and a second adhesive member 8. The optical function unit 5 is provided on the metal substrate 3. The actuator device 1 is housed in, for example, a package (not shown). As an example, the package has a side wall, a bottom wall, and a top wall made of a light-transmitting material, and is box-shaped. For example, in the actuator device 1, when a laser beam enters the package through the top wall, the laser beam is reflected by the optical surface 51 of the optical function unit 5 that is periodically oscillated through the metal substrate 3 by the driving piezoelectric element 6, and is emitted to the outside through the top wall. The emission direction of the laser beam from the package changes periodically and continuously according to the oscillation of the optical surface 51. That is, in this embodiment, the actuator device 1 is an optical scanning device.

[0018] The wiring board 2 has a mounting surface 2a. The wiring board 2 has an opening 2b that opens on the mounting surface 2a and the surface opposite to the mounting surface 2a. The wiring board 2 has, for example, a rectangular frame shape. Examples of materials for the wiring board 2 include silicon, ceramic, quartz, glass, and plastic. For example, the wiring board 2 may be a glass composite board (CEM-3) in which a base material made of a mixture of glass cloth and nonwoven glass cloth is impregnated with epoxy resin, a glass epoxy board (FR-4) in which a layer of glass fiber cloth is impregnated with epoxy resin, or a metal heat dissipation board with a base material of copper, aluminum, or the like. The thickness of the wiring board 2 may be a thickness that ensures sufficient rigidity, for example, 0.8 mm or more. In this embodiment, the thickness of the wiring board 2 is 1.6 mm. In the following description, the thickness direction of the wiring board 2 is referred to as the Z-axis direction (the thickness direction of the metal board), the direction perpendicular to the Z-axis direction is referred to as the X-axis direction, and the direction perpendicular to both the Z-axis direction and the X-axis direction is referred to as the Y-axis direction (the direction in which the main body portion 31 and the movable portion 32 are aligned).

[0019] A plurality of electrode pads 21, 22, 23 (three in this embodiment) are arranged on the mounting surface 2a of the wiring board 2. The plurality of electrode pads 21, 22, 23 are located on one side in the Y-axis direction with respect to the opening 2b of the wiring board 2, and are lined up along the X-axis direction. A connector 24 is attached to the mounting surface 2a. The connector 24 is a port for inputting and outputting voltage signals, etc., to each of the driving piezoelectric element 6 and the detecting piezoelectric element 7. The connector 24 is located, for example, on one side in the Y-axis direction with respect to the plurality of electrode pads 21, 22, 23. The connector 24 has a plurality of terminals 25. The connector 24 is electrically connected to the plurality of electrode pads 21, 22, 23 via the plurality of terminals 25 and wiring of the wiring board 2, etc.

[0020] The metal substrate 3 is supported by the wiring substrate 2. The metal substrate 3 is made of, for example, an iron-based, stainless steel-based, copper-based, permalloid-based, titanium-based, tungsten-based, molybdenum-based metal, or the like, and has a plate shape. The thickness of the metal substrate 3 is, for example, 50 to 500 μm. The first adhesive member 4 bonds the wiring substrate 2 and the metal substrate 3. The first adhesive member 4 is conductive. An example of a material for the first adhesive member 4 is an epoxy resin containing Ag particles.

[0021] The metal substrate 3 has a main body portion 31, a movable portion 32, a first extending portion 33, a second extending portion 34, a first connecting portion 35, a second connecting portion 36, a first connecting portion 37, a second connecting portion 38, and a third connecting portion 39. The movable portion 32, the first extending portion 33, the second extending portion 34, the first connecting portion 35, the second connecting portion 36, the first connecting portion 37, the second connecting portion 38, and the third connecting portion 39 are integrally formed.

[0022] The main body 31 is a portion where the driving piezoelectric element 6 is fixed (placed). When viewed from the Z-axis direction, the main body 31 is located within the opening 2b of the wiring board 2. The movable portion 32 is a portion where the optical function portion 5 is placed. The movable portion 32 is located on the other side of the main body 31 in the Y-axis direction.

[0023] The first extension portion 33 and the second extension portion 34 extend from the main body portion 31 so that the movable portion 32 is located therebetween. In this embodiment, the movable portion 32 is located midway between the first extension portion 33 and the second extension portion 34. The first extension portion 33 and the second extension portion 34 extend parallel to each other, for example, along the Y-axis direction. In this embodiment, the first extension portion 33 has the same shape as the second extension portion 34. Note that it is sufficient that the first extension portion 33 and the second extension portion 34 extend from the main body portion 31 so that at least a portion of the movable portion 32 is located therebetween (i.e., the movable portion 32 is located between the first extension portion 33 and the second extension portion 34 in the X-axis direction).

[0024] The first connecting portion 35 extends along the X-axis direction between the first extending portion 33 and the movable portion 32. One end of the first connecting portion 35 is connected to the first extending portion 33, and the other end of the first connecting portion 35 is connected to the movable portion 32. In other words, the first connecting portion 35 connects the first extending portion 33 and the movable portion 32 together.

[0025] The second connecting portion 36 extends along the X-axis direction between the second extending portion 34 and the movable portion 32. One end of the second connecting portion 36 is connected to the second extending portion 34, and the other end of the second connecting portion 36 is connected to the movable portion 32. In other words, the second connecting portion 36 connects the second extending portion 34 and the movable portion 32 together.

[0026] In this embodiment, the first connecting portion 35 and the second connecting portion 36 are located on a single straight line along the X-axis direction. Due to the positional relationship between the first extending portion 33 and the second extending portion 34 and the movable portion 32 described above, the length of the first connecting portion 35 in the X-axis direction is the same as the length of the second connecting portion 36 in the X-axis direction. In this embodiment, the first connecting portion 35 has the same shape as the second connecting portion 36.

[0027] The movable part 32, the first extending part 33, the second extending part 34, the first connecting part 35 and the second connecting part 36 are located within the opening 2b of the wiring board 2 when viewed from the Z-axis direction. The first connecting part 35 and the second connecting part 36 function as a torsion bar that elastically deforms so as to twist in response to the deformation (displacement) of the first extending part 33 and the second extending part 34. The movable part 32 swings around an axis along the X-axis direction in response to the elastic deformation of the first connecting part 35 and the second connecting part 36. That is, the movable part 32 is swingably supported by the first extending part 33 and the second extending part 34 via the first connecting part 35 and the second connecting part 36.

[0028] The optical function part 5 is disposed on the surface of the movable part 32 opposite to the opening 2b. The optical function part 5 is, for example, disk-shaped. The optical function part 5 is attached to the movable part 32 so that the optical surface 51 faces the opposite side to the movable part 32. The optical surface 51 is located midway between the first extension part 33 and the second extension part 34 in the X-axis direction. In this embodiment, the metal substrate 3 and the optical surface 51 each have a shape that is line-symmetrical with respect to a straight line passing through the center of the optical surface 51 along the Y-axis direction. As an example, the optical function part 5 is made of a semiconductor material such as silicon or glass, and the optical surface 51 is composed of a reflective film formed on the surface of the optical function part 5 opposite to the movable part 32. That is, the optical surface 51 is a mirror surface (reflective surface). The reflective film of the optical function part 5 can be omitted. In that case, the opposite surface itself may be the optical surface 51.

[0029] The first connection portion 37 is connected to the first extension portion 33. The first connection portion 37 is located on the other side in the Y-axis direction with respect to the first extension portion 33. A portion of the first connection portion 37 on the other side in the Y-axis direction faces a part of the wiring board 2. A first adhesive member 4 is disposed between the other side portion of the first connection portion 37 and the part of the wiring board 2. Note that an electrode pad (not shown) electrically connected to the electrode pad 23 so as to have the same potential as the electrode pad 23 may be disposed on the part of the wiring board 2.

[0030] The second connection portion 38 is connected to the second extension portion 34. The second connection portion 38 is located on the other side in the Y-axis direction with respect to the second extension portion 34. In the second connection portion 38, a portion on the other side in the Y-axis direction faces a part of the wiring board 2. A first adhesive member 4 is disposed between the portion on the other side of the second connection portion 38 and the part of the wiring board 2. Note that an electrode pad (not shown) electrically connected to the electrode pad 23 so as to have the same potential as the electrode pad 23 may be disposed on the part of the wiring board 2. In this embodiment, the first connection portion 37 and the second connection portion 38 are in a line-symmetrical relationship with respect to a straight line passing through the center of the optical surface 51 along the Y-axis direction.

[0031] The third connection portion 39 is connected to the main body 31. The third connection portion 39 is located on one side in the Y-axis direction with respect to the main body 31. A portion of the third connection portion 39 on one side in the Y-axis direction faces a part of the wiring board 2 (a portion where the electrode pad 23 is arranged). The first adhesive member 4 is arranged between the portion on the one side of the third connection portion 39 and the part of the wiring board 2.

[0032] The driving piezoelectric element 6 is an element for generating plate waves in the metal substrate 3 to drive the actuator device 1. The driving piezoelectric element 6 is disposed on the mounting surface 31a on the opposite side to the opening 2b in the main body 31. The center of the driving piezoelectric element 6 in the X-axis direction coincides with the center of the movable part 32 in the X-axis direction (i.e., the center of the optical surface 51 in the X-axis direction). The driving piezoelectric element 6 includes a driving piezoelectric body 61, a first electrode 62, and a second electrode (not shown).

[0033] The driving piezoelectric body 61 includes a first main surface 61a and a second main surface (not shown). The first main surface 61a is a main surface of the driving piezoelectric body 61 on the opposite side to the mounting surface 31a. A first electrode 62 is disposed on the first main surface 61a. The second main surface is a main surface of the driving piezoelectric body 61 on the mounting surface 31a side. A second electrode is disposed on the second main surface. Each of the first electrode 62 and the second electrode is, for example, a Ni / Au layer. In the Ni / Au layer, the Ni layer is disposed on the first main surface 61a, the Au layer is disposed on the Ni layer, and the thickness of the Ni layer is larger than the thickness of the Au layer. Each of the driving piezoelectric body 61, the first electrode 62, and the second electrode is, for example, rectangular plate-shaped. The driving piezoelectric body 61 is electrically connected to the first electrode 62 by being bonded to the first electrode 62. The driving piezoelectric body 61 is bonded to the second electrode, and is thereby electrically connected to the second electrode. A second adhesive member 8 is disposed between the second electrode and the main body portion 31. The second adhesive member 8 bonds the driving piezoelectric body 61 to the metal substrate 3. The second adhesive member 8 has electrical conductivity. An example of a material for the second adhesive member 8 is an epoxy resin containing Ag particles.

[0034] The detection piezoelectric element 7 is an element for detecting the amount of movement of the movable part 32. In this embodiment, the detection piezoelectric element 7 detects the swing angle and phase of the movable part 32. The detection piezoelectric element 7 is disposed on the surface 62a. The surface 62a is a main surface of the first electrode 62 opposite to the driving piezoelectric body 61. The center of the detection piezoelectric element 7 in the X-axis direction coincides with the center of the driving piezoelectric element 6 in the X-axis direction. The detection piezoelectric element 7 includes a detection piezoelectric body 71, a third electrode 72, and a fourth electrode (not shown). The detection piezoelectric body 71 includes a third main surface 71a and a fourth main surface (not shown). The third main surface 71a is a main surface of the detection piezoelectric body 71 opposite to the first electrode 62. The third electrode 72 is disposed on the third main surface 71a. The fourth main surface is a main surface of the detection piezoelectric body 71 on the first electrode 62 side. The fourth electrode is disposed on the fourth main surface. The third electrode 72 and the fourth electrode are, for example, Ni / Au layers. The detection piezoelectric body 71, the third electrode 72, and the fourth electrode are, for example, rectangular plate-shaped. The detection piezoelectric body 71 is bonded to the third electrode 72 and thereby electrically connected to the third electrode 72. The driving piezoelectric body 61 is bonded to the fourth electrode and thereby electrically connected to the fourth electrode. A second adhesive member 8 is disposed between the fourth electrode and the first electrode 62. The second adhesive member 8 bonds the detection piezoelectric body 71 and the driving piezoelectric body 61 together.

[0035] Here, the electrical connection relationships between the wiring board 2, the metal board 3, the driving piezoelectric element 6, and the detecting piezoelectric element 7 will be described. As shown in Fig. 2, the first electrode 62 of the driving piezoelectric element 6 is electrically connected to the electrode pad 21 via the wire 11. The electrode pad 21 is electrically connected to the terminal 25 of the connector 24 via the wiring of the wiring board 2. In other words, the first electrode 62 of the driving piezoelectric element 6 is electrically connected to the connector 24 via the wire 11, the electrode pad 21, and the wiring of the wiring board 2.

[0036] The second electrode of the driving piezoelectric element 6 is electrically connected to the metal substrate 3 via the second adhesive member 8 arranged between the second electrode and the main body 31. The third connection portion 39 of the metal substrate 3 is electrically connected to the electrode pad 23 via the first adhesive member 4 arranged between the third connection portion 39 and the electrode pad 23. The electrode pad 23 is electrically connected to the terminal 25 of the connector 24 via the wiring of the wiring substrate 2. In other words, the second electrode of the driving piezoelectric element 6 is electrically connected to the connector 24 via the second adhesive member 8, the metal substrate 3, the first adhesive member 4, the electrode pad 23, and the wiring of the wiring substrate 2.

[0037] The third electrode 72 of the detecting piezoelectric body 71 is electrically connected to the electrode pad 22 via the wire 12. The electrode pad 22 is electrically connected to the terminal 25 of the connector 24 via the wiring of the wiring board 2. In other words, the third electrode 72 of the detecting piezoelectric body 71 is electrically connected to the connector 24 via the wire 12, the electrode pad 22, and the wiring of the wiring board 2.

[0038] The fourth electrode of the detection piezoelectric element 7 is electrically connected to the first electrode 62 of the driving piezoelectric element 6 via the second adhesive member 8 disposed between the fourth electrode and the first electrode 62 of the driving piezoelectric element 6. In other words, the fourth electrode of the detection piezoelectric element 7 is electrically connected to the connector 24 via the second adhesive member 8, the first electrode 62 of the driving piezoelectric element 6, the wire 11, the electrode pad 21, and the wiring of the wiring board 2.

[0039] Due to the electrical connection relationship as described above, the actuator device 1 is driven, for example, as follows. Specifically, in a state in which the first electrode 62 of the driving piezoelectric element 6 and the fourth electrode of the detecting piezoelectric element 7 are connected to a reference potential (for example, ground potential) via the wire 11, the electrode pad 21, the wiring of the wiring board 2, and the connector 24, a driving voltage signal is input from the outside of the actuator device 1 to the second electrode of the driving piezoelectric element 6 via the connector 24, the wiring of the wiring board 2, the electrode pad 23, the first adhesive member 4, the metal board 3, and the second adhesive member 8. This causes the driving piezoelectric element 6 to deform and / or vibrate, and periodic plate waves are generated in the main body 31. Due to the generation of this periodic plate wave, torsional vibration (torsional resonance) is induced in the first connecting portion 35 and the second connecting portion 36, and the movable portion 32 and the optical surface 51 oscillate. That is, in the actuator device 1, the torsional resonance system of the first connecting portion 35, the second connecting portion 36, the movable portion 32, and the optical surface 51 is disposed at a distance from the driving piezoelectric element 6, and a Lamb wave resonance structure is adopted, so that torsional resonance is generated with high driving efficiency. Meanwhile, a voltage signal corresponding to the change in angle due to the oscillation of the movable portion 32 and the optical surface 51 is outputted from the third electrode 72 of the detecting piezoelectric body 71 to the outside of the actuator device 1 via the wire 12, the electrode pad 22, the wiring of the wiring board 2, and the connector 24, and the oscillation angle and phase of the optical surface 51 are detected. The actuator device 1 includes a piezoelectric unit 10. The piezoelectric unit 10 is composed of the metal substrate 3, the driving piezoelectric element 6, the detecting piezoelectric element 7, and the second adhesive member 8 described above. [Configuration of wiring board, metal board, and first adhesive member]

[0040] As shown in FIG. 3, the first connection portion 37 includes a first region R1, a second region R2, and a third region R3. The first region R1 is a region facing the portion 26 in the Z-axis direction. The portion 26 is a part of the wiring board 2. The second region R2 is a region continuing from the first region R1. The third region R3 is a region continuing from the second region R2 and connected to the first extension portion 33. The "region connected to the first extension portion 33" includes both a region where the third region R3 is directly connected to the first extension portion 33 (i.e., not via another portion) and a region where the third region R3 is indirectly connected to the first extension portion 33 (i.e., via another portion). In other words, the third region R3 is not limited to the entire portion between the first extension portion 33 and the second region R2 in the first connection portion 37, but is a region that is continuously connected to the second region R2. In this embodiment, the second region R2 and the third region R3 do not face the wiring board 2 in the Z-axis direction.

[0041] In the following description, when viewed from the Z-axis direction, the direction in which the third region R3 is connected to the second region R2 is defined as a connection direction A, and the direction perpendicular to the connection direction A is defined as a direction B. In this embodiment, when viewed from the Z-axis direction, the connection direction A intersects with each of the X-axis direction and the Y-axis direction. In this embodiment, when viewed from the Z-axis direction, the region consisting of the first region R1 and the second region R2 has a polygonal shape, and the second region R2 forms one corner K of the polygonal shape. As an example, when viewed from the Z-axis direction, the region consisting of the first region R1 and the second region R2 has a substantially rectangular shape, and the boundary between the first region R1 and the second region R2 is curved so as to be convex on the opposite side to the apex of the corner K. When viewed from the Z-axis direction, the second region R2 has, for example, a fan shape. As an example, when viewed from the Z-axis direction, the third region R3 has a rectangular shape with the connection direction A as its longitudinal direction, and is connected to the part of the second region R2 that is furthest to the one side in the X-axis direction and furthest to the one side in the Y-axis direction.

[0042] When viewed from the Z-axis direction, the width W2 of the second region R2 in direction B is larger than the width W3 of the third region R3 in direction B. "When viewed from the Z-axis direction, the width W2 of the second region R2 in direction B is larger than the width W3 of the third region R3 in direction B" means that, when viewed from the Z-axis direction, the minimum value of the width W2 of the second region R2 in direction B is larger than the maximum value of the width W3 of the third region R3 in direction B, excluding the boundary portion between the second region R2 and the third region R3.

[0043] In addition, with respect to the first region R1 facing the portion 26 of the wiring board 2 in the Z-axis direction, the second region R2 includes i) a region that does not face the wiring board 2 in the Z-axis direction, or ii) a region whose distance to the wiring board 2 in the Z-axis direction is greater than the distance between the first region R1 and the wiring board 2 in the Z-axis direction. In this embodiment, the second region R2 is i) a region that does not face the wiring board 2 in the Z-axis direction.

[0044] The boundary between the second region R2 and the third region R3 includes i) the "line along direction B" when the width of the first connection portion 37 in direction B changes discontinuously at the "line along direction B", ii) the "line along direction B" when the rate of change of the width of the first connection portion 37 in direction B changes discontinuously at the "line along direction B", or iii) the "line along direction B" when the width of the first connection portion 37 in direction B exceeds 1.1 times the minimum value of the width of the first connection portion 37 in direction B at the "line along direction B". In this embodiment, the boundary between the second region R2 and the third region R3 is iii) the "line along direction B" when the width of the first connection portion 37 in direction B exceeds 1.1 times the minimum value of the width of the first connection portion 37 in direction B at the "line along direction B". The third region R3 is a region that includes at least the portion of the first connection portion 37 that has the minimum width of the first connection portion 37 in direction B, and the second portion of the first adhesive member 4 (described in detail later) does not extend beyond the line that defines the minimum width of the first connection portion 37 in direction B.

[0045] When viewed from the Z-axis direction, the width W1 of the first region R1 in direction B is larger than the width W2 of the second region R2 in direction B. "When viewed from the Z-axis direction, the width W1 of the first region R1 in direction B is larger than the width W2 of the second region R2 in direction B" means that when viewed from the Z-axis direction, the maximum value of the width W1 of the first region R1 in direction B is larger than the maximum value of the width W2 of the second region R2 in direction B. In this way, when viewed from the Z-axis direction, the width of the first connection portion 37 in direction B increases stepwise from the third region R3 toward the first region R1.

[0046] In this embodiment, when viewed from the Z-axis direction, the area of ​​the first region R1 is larger than the area of ​​the second region R2, and the area of ​​the second region R2 is larger than the area of ​​the third region R3. Furthermore, when viewed from the Z-axis direction, the area of ​​the first region R1 is larger than the sum of the areas of the second region R2 and the third region R3. The rigidity of the second region R2 is larger than the rigidity of the third region R3. The rigidity of the first region R1 is larger than the rigidity of the second region R2.

[0047] The first adhesive member 4 (see FIG. 2, etc.) bonds the portion 26 of the wiring board 2 to the first connection portion 37. The first adhesive member 4 has a first portion (not shown) and a second portion (not shown). The first portion is a portion of the first adhesive member 4 that is disposed between the portion 26 and the first region R1. The second portion is a portion of the first adhesive member 4 that is continuous from the first portion, reaches the second region R2, and does not reach the third region R3. That is, the second portion is in contact with the second region R2, but is not in contact with the third region R3. As an example, the second portion is in contact with the side of the second region R2 and the portion 26, and the surface of the second portion opposite to the second region R2 is exposed to space. That is, the first adhesive member 4 is in contact with each of the first region R1 and the second region R2, but is not in contact with the third region R3. In this way, in the first connection portion 37, the second region R2 is provided between the first region R1 and the third region R3, so that in the metal substrate 3, the first adhesive member 4 protruding from the first region R1 remains in the second region R2, and the first adhesive member 4 is not in contact with the third region R3 connected to the first extension portion 33.

[0048] As shown in FIG. 4, the second connection portion 38 includes a first region R1, a second region R2, and a third region R3, similar to the first connection portion 37. The first region R1 of the second connection portion 38 is a region facing the portion 27, which is a part of the wiring board 2, in the Z-axis direction. The second region R2 of the second connection portion 38 is a region continuing from the first region R1. The third region R3 of the second connection portion 38 is a region continuing from the second region R2 and connected to the second extension portion 34. The first adhesive member 4 (see FIG. 2, etc.) bonds the portion 27 of the wiring board 2 and the second connection portion 38. The first adhesive member 4 bonding the portion 27 of the wiring board 2 and the second connection portion 38 also has a first portion (not shown) and a second portion (not shown), similar to the first adhesive member 4 bonding the portion 26 and the first connection portion 37. The configurations of the second connecting portion 38 and the first adhesive member 4 are similar to the configurations of the first connecting portion 37 and the first adhesive member 4 (they are in a line-symmetric relationship with respect to a line passing through the center of the optical surface 51 along the Y-axis direction).

[0049] As shown in FIG. 5, the third connection portion 39 includes a fourth region R4, a fifth region R5, and a sixth region R6. The fourth region R4 is a region facing the portion 28 in the Z-axis direction. The portion 28 is a part of the wiring board 2 that is separate from the portion 26. The fifth region R5 is a region that is continuous with the fourth region R4. The sixth region R6 is a region that is continuous with the fifth region R5 and is connected to the main body portion 31. The "region that is connected to the main body portion 31" includes both a region where the sixth region R6 is directly connected to the main body portion 31 (i.e., not via another portion) and a region where the sixth region R6 is indirectly connected to the main body portion 31 (i.e., via another portion). In other words, the sixth region R6 is not limited to the entire portion between the main body portion 31 and the fifth region R5 in the third connection portion 39, but is a region that is continuously connected to the fifth region R5.

[0050] In the following description, when viewed from the Z-axis direction, the direction in which the sixth region R6 is connected to the fifth region R5 (another connection direction) is defined as the connection direction C, and the direction perpendicular to the connection direction C is defined as the direction D. In this embodiment, when viewed from the Z-axis direction, the region consisting of the fourth region R4 and the fifth region R5 has a polygonal shape, and the fifth region R5 constitutes a part of one side of the polygonal shape. As an example, when viewed from the Z-axis direction, the region consisting of the fourth region R4 and the fifth region R5 has a rectangular shape, and the boundary line between the fourth region R4 and the fifth region R5 is curved so as to be convex on the opposite side to the side. When viewed from the Z-axis direction, the fifth region R5 has, for example, a semi-elliptical shape. When viewed from the Z-axis direction, the sixth region R6 has, for example, a substantially rectangular shape, and is connected to the center in the X-axis direction and the othermost side in the Y-axis direction in the second region R2.

[0051] When viewed from the Z-axis direction, the width W5 of the fifth region R5 in the direction D is larger than the width W6 of the sixth region R6 in the direction D. "When viewed from the Z-axis direction, the width W5 of the fifth region R5 in the direction D is larger than the width W6 of the sixth region R6 in the direction D" means that, when viewed from the Z-axis direction, the minimum value of the width W5 of the fifth region R5 in the direction D is larger than the maximum value of the width W6 of the sixth region R6 in the direction D, except for the boundary portion between the fifth region R5 and the sixth region R6.

[0052] In addition, with respect to the fourth region R4 facing the portion 28 of the wiring board 2 in the Z-axis direction, the fifth region R5 includes i) a region that does not face the wiring board 2 in the Z-axis direction, or ii) a region whose distance to the wiring board 2 in the Z-axis direction is greater than the distance in the Z-axis direction between the fourth region R4 and the wiring board 2. In this embodiment, the fifth region R5 is i) a region that does not face the wiring board 2 in the Z-axis direction.

[0053] The boundary between the fifth region R5 and the sixth region R6 includes i) the "line along the direction D" when the width of the third connection portion 39 in the direction D changes discontinuously at the "line along the direction D", ii) the "line along the direction D" when the rate of change of the width of the third connection portion 39 in the direction D changes discontinuously at the "line along the direction D", or iii) the "line along the direction D" when the width of the third connection portion 39 in the direction D exceeds 1.1 times the minimum value of the width of the third connection portion 39 in the direction D at the "line along the direction D". In this embodiment, the boundary between the fifth region R5 and the sixth region R6 is iii) the "line along the direction D" when the width of the third connection portion 39 in the direction D exceeds 1.1 times the minimum value of the width of the third connection portion 39 in the direction D at the "line along the direction D". The sixth region R6 is a region that includes at least the portion of the third connection portion 39 that has the minimum width of the third connection portion 39 in direction D, and the fourth portion (described in detail later) of the first adhesive member 4 does not extend beyond the line that defines the minimum width of the third connection portion 39 in direction D.

[0054] When viewed from the Z-axis direction, the width W4 of the portion of the fourth region R4 in the direction D located on one side of the fifth region R5 in the Y-axis direction is larger than the width W5 of the fifth region R5 in the direction D. "When viewed from the Z-axis direction, the width W4 of the portion of the fourth region R4 in the direction D located on one side of the fifth region R5 in the Y-axis direction in the direction D is larger than the width W5 of the fifth region R5" means that when viewed from the Z-axis direction, the maximum value of the width W4 in the direction D is larger than the maximum value of the width W5 of the fifth region R5 in the direction D. In this way, when viewed from the Z-axis direction, the width of the third connection portion 39 in the direction D increases stepwise from the sixth region R6 toward the fourth region R4.

[0055] In this embodiment, when viewed from the Z-axis direction, the area of ​​the fourth region R4 is larger than the area of ​​the fifth region R5. Furthermore, when viewed from the Z-axis direction, the area of ​​the fourth region R4 is larger than the sum of the areas of the fifth region R5 and the sixth region R6. The rigidity of the fifth region R5 is larger than the rigidity of the sixth region R6. The rigidity of the fourth region R4 is larger than the rigidity of the fifth region R5.

[0056] In this embodiment, the fifth region R5 and the sixth region R6 do not face the wiring board 2 in the Z-axis direction. The first adhesive member 4 bonds the portion (another portion) 28 of the wiring board 2 and the third connection portion 39. The first adhesive member 4 (see FIG. 2, etc.) has a third portion (not shown) and a fourth portion (not shown). The third portion is a portion of the first adhesive member 4 that is disposed between the portion 28 and the fourth region R4. The fourth portion is a portion of the first adhesive member 4 that is continuous from the third portion, reaches the fifth region R5, and does not reach the sixth region R6. That is, the fourth portion is in contact with the fifth region R5 and is not in contact with the sixth region R6. As an example, the fourth portion is in contact with the side surface of the fifth region R5 and the portion 28, and the surface of the fourth portion opposite to the fifth region R5 is exposed to the space. That is, the first adhesive member 4 is in contact with each of the fourth region R4 and the fifth region R5, but is not in contact with the sixth region R6. In this manner, in the third connection portion 39, the fifth region R5 is provided between the fourth region R4 and the sixth region R6, and therefore, in the metal substrate 3, the first adhesive member 4 protruding from the fourth region R4 remains in the fifth region R5, and the first adhesive member 4 is not in contact with the sixth region R6 connected to the main body portion 31. [Configuration of each connection]

[0057] As shown in FIG. 3 and FIG. 6, the first connection portion 37 further includes a first fixing region 371 and a first connection region 372. The first fixing region 371 is fixed to the wiring board 2. In this embodiment, at least a part of the first fixing region 371 is fixed to the wiring board 2. Specifically, the first fixing region 371 includes a first region R1 that faces the portion 26 of the wiring board 2 and is fixed to the portion 26 by the first adhesive member 4 (see FIG. 2, etc.), and a second region R2 that does not face the wiring board 2 and is fixed to the portion 26 by the first adhesive member 4. Note that the first fixing region 371 may further include a portion that does not face a part of the wiring board 2 and is not fixed to the wiring board 2.

[0058] The first connection region 372 is a region connected to the first extension portion 33 and the first fixed region 371. The entire boundary between the first connection region 372 and the first fixed region 371 is formed on the movable portion 32 side in the X-axis direction with respect to the connection point between the first connection region 372 and the first extension portion 33. The first connection region 372 includes a third region R3. As shown in FIG. 6, the first connection region 372 includes a portion (first portion) 372a, a portion (third portion) 372b, and a first curved portion 372c. The portion 372a is a portion that extends linearly from the first extension portion 33. The portion 372a is located on the furthest side in the Y-axis direction of the first connection region 372. In this embodiment, the portion 372a extends along the Y-axis direction.

[0059] The portion 372b has a positional relationship in which it intersects with the portion 372a, and is a portion extending linearly from the first fixed region 371. The positional relationship in which the portion 372b intersects with the portion 372a means, for example, that the portion 372a and the portion 372b are in a positional relationship in which the direction along the center line L2 of the portion 372b intersects with the direction along the center line L1 of the portion 372a. That is, the center line L1 of the portion 372a is not parallel to the center line L2 of the portion 372b. The portion 372b is located on the other side of the first connection region 372 in the Y-axis direction. In this embodiment, the portion 372b extends along a direction intersecting each of the X-axis direction and the Y-axis direction.

[0060] The first curved portion 372c is bent toward the movable portion 32 in the first connection region 372. In this embodiment, the first curved portion 372c is a portion connected to the portion 372a and the portion 372b. That is, the first curved portion 372c is located between the portion 372a and the portion 372b. The first curved portion 372c has a first outer edge P1 on the movable portion 32 side and a second outer edge P2 on the opposite side to the movable portion 32. Each of the first outer edge P1 and the second outer edge P2 is bent toward the movable portion 32 side when viewed from the Z-axis direction. That is, the first connection region 372 is bent at the first curved portion 372c. In this embodiment, each of the first outer edge P1 and the second outer edge P2 is curved so as to be convex toward the opposite side to the movable portion 32 when viewed from the Z-axis direction.

[0061] When viewed from the Z-axis direction, the angle θ1 that the portion 372b forms with respect to the Y-axis direction is greater than 0 degrees and equal to or less than 90 degrees. The angle θ1 that the portion 372b forms with respect to the Y-axis direction is, for example, the angle that the center line L2 of the portion 372b forms with respect to the Y-axis direction. In other words, the angle θ1 is an angle that indicates the inclination of the portion 372b toward the movable part 32 when the Y-axis direction is used as a reference. As an example, the angle θ1 is about 45 degrees.

[0062] As shown in FIG. 4 and FIG. 7, the second connection portion 38 further includes a second fixing region 381 and a second connection region 382. The second fixing region 381 is fixed to the wiring board 2 in the same manner as the first fixing region 371. In this embodiment, at least a portion of the second fixing region 381 is fixed to the wiring board 2. Specifically, the second fixing region 381 includes a first region R1 that faces the portion 27 of the wiring board 2 and is fixed to the portion 27 by the first adhesive member 4 (see FIG. 2, etc.) in the same manner as the first fixing region 371, and a second region R2 that does not face the wiring board 2 and is fixed to the portion 27 by the first adhesive member 4 reaching thereto. Note that the second fixing region 381 may further include a portion that does not face a portion of the wiring board 2 and is not fixed to the wiring board 2.

[0063] The second connection region 382 is a region connected to the second extension portion 34 and the second fixing region 381, similar to the first connection region 372. The entire boundary between the second connection region 382 and the second fixing region 381 is formed on the movable portion 32 side in the X-axis direction with respect to the connection point between the second connection region 382 and the second extension portion 34. The second connection region 382 includes the third region R3, similar to the first connection region 372. As shown in FIG. 7, the second connection region 382 includes a portion (second portion) 382a, a portion (fourth portion) 382b, and a second curved portion 382c. The portion 382a is a portion that extends linearly from the second extension portion 34. The portion 382a is located on the furthest side in the Y-axis direction of the second connection region 382. In this embodiment, the portion 382a extends along the Y-axis direction.

[0064] The portion 382b is positioned so as to intersect with the portion 382a, and extends linearly from the second fixing region 381. That is, the center line L3 of the portion 382a is not parallel to the center line L4 of the portion 382b. The portion 382b is located on the othermost side in the Y-axis direction of the second connection region 382. In this embodiment, the portion 382b extends along a direction intersecting with both the X-axis direction and the Y-axis direction.

[0065] The second curved portion 382c is curved toward the movable portion 32 in the second connection region 382. In this embodiment, the second curved portion 382c is a portion connected to the portion 382a and the portion 382b. The second curved portion 382c has a third outer edge P3 on the movable portion 32 side and a fourth outer edge P4 on the opposite side to the movable portion 32. Each of the third outer edge P3 and the fourth outer edge P4 is curved toward the movable portion 32 when viewed from the Z-axis direction. That is, the second connection region 382 is bent at the second curved portion 382c. In this embodiment, each of the third outer edge P3 and the fourth outer edge P4 is curved so as to be convex toward the opposite side to the movable portion 32 when viewed from the Z-axis direction.

[0066] When viewed from the Z-axis direction, the angle θ2 that portion 382b makes with respect to the Y-axis direction is greater than 0 degrees and less than or equal to 90 degrees, for example, approximately 45 degrees. As described above, the configurations of second fixing region 381 and second connection region 382 are similar to the configurations of first fixing region 371 and first connection region 372 (they are in a line-symmetric relationship with respect to a straight line that passes through the center of optical surface 51 along the Y-axis direction).

[0067] 2, the first fixing region 371 and the second fixing region 381 are spaced apart from each other with a region Rh therebetween. The region Rh is located on the opposite side of the movable portion 32 from the main body portion 31 in the Y-axis direction. In this embodiment, the region Rh is a space. That is, in this embodiment, the first fixing region 371 and the second fixing region 381 are spaced apart from each other. Note that the region Rh may include an object other than a space.

[0068] As shown in FIG. 5, the third connection portion 39 further includes a third fixing region 391 and a third connection region 392. The third fixing region 391 is a region fixed to the wiring board 2. In this embodiment, at least a part of the third fixing region 391 is fixed to the wiring board 2. Specifically, the third fixing region 391 includes a fourth region R4 that faces the portion 28 of the wiring board 2 and is fixed to the portion 28 by the first adhesive member 4 (see FIG. 2, etc.), and a fifth region R5 that does not face the wiring board 2 and is fixed to the portion 28 by the first adhesive member 4 reaching thereto. The third connection region 392 is a region that is connected to the main body 31 and the third fixing region 391. The third connection region 392 includes a sixth region R6. The third fixing region 391 may further include a portion that does not face a part of the wiring board 2 and is not fixed to the wiring board 2. As an example, the third connection region 392 extends linearly from the main body portion 31 along the Y-axis direction. [Action and Effects]

[0069] In the actuator device 1, even if the wiring board 2 expands or contracts due to, for example, a change in the environmental temperature, the first curved portion 372c deforms in the first connection region 372 and the second curved portion 382c deforms in the second connection region 382, ​​so that unnecessary stress is less likely to act on the first coupling portion 35, the second coupling portion 36 and the main body portion 31 via the first fixing region 371 and the second fixing region 381 fixed to the wiring board 2, and unnecessary stress is less likely to act on the main body portion 31 via the third fixing region 391 fixed to the wiring board 2, thereby suppressing a change in the resonance frequency of the metal substrate 3. Therefore, according to this actuator device 1, desired drive characteristics can be stably obtained even if, for example, the environmental temperature changes.

[0070] The effect of the actuator device 1 will be further described. In the actuator device 1, when the wiring board 2 expands or contracts due to, for example, a change in the environmental temperature, the first fixing region 371 moves along a direction inclined toward the opposite side of the movable part 32 with respect to the Y-axis direction, and the second fixing region 381 moves along a direction inclined toward the opposite side of the movable part 32 with respect to the Y-axis direction. As an example, when the wiring board 2 expands, the first fixing region 371 moves outward along the above-mentioned direction, and the second fixing region 381 moves outward along the above-mentioned direction. In such an actuator device 1, if each of the connection regions 372, 382 extends linearly from each of the extension parts 33, 34 to each of the fixing regions 371, 381 along the Y-axis direction without including each of the curved parts 372c, 382c, the following problem may occur. In other words, in the above configuration, if the wiring board 2 expands or contracts due to, for example, a change in environmental temperature, each connection area 372, 382 does not include a portion that deforms, and therefore unnecessary stress acts on the first connecting portion 35, the second connecting portion 36 and the main body portion 31 via each fixed area 371, 381, resulting in a change in the resonant frequency of the metal board 3.

[0071] In addition, if, as viewed from the Z-axis direction, in the first connection region 372, the first outer edge P1 and the second outer edge P2 are each bent toward the opposite side to the movable part 32, and the portion 372b is inclined toward the opposite side to the movable part 32 with respect to the Y-axis direction, and in the second connection region 382, ​​the third outer edge P3 and the fourth outer edge P4 are each bent toward the opposite side to the movable part 32, and the portion 372b is inclined toward the opposite side to the movable part 32 with respect to the Y-axis direction, the following problem may occur. That is, in the above configuration, for example, when the wiring board 2 expands or contracts due to a change in the environmental temperature, the direction in which the portion 372b extends and the direction in which the first fixing region 371 moves become nearly parallel, and the direction in which the portion 382b extends and the direction in which the second fixing region 381 moves become nearly parallel, so that the curved portions 372c, 382c are less likely to deform. As a result, unnecessary stress acts on the first connecting portion 35, the second connecting portion 36 and the main body portion 31 via the fixing regions 371, 381, and 391, causing the resonance frequency of the metal substrate 3 to change.

[0072] Furthermore, the drive voltage for obtaining a desired swing angle in the movable part 32 is affected by the ratio between the resonance frequency in the resonance mode of the entire metal substrate 3 (hereinafter referred to as the "leaf spring resonance mode") and the resonance frequency in the resonance mode of the movable part 32. Therefore, for example, in each of the above configurations, if the wiring substrate 2 expands or contracts due to a change in the environmental temperature, unnecessary stress acts on the first connecting part 35, the second connecting part 36, and the main body part 31 via the fixing regions 371, 381, and the resonance frequency in the leaf spring resonance mode changes, which may cause a change in the ratio between the resonance frequency in the leaf spring resonance mode and the resonance frequency in the movable part resonance mode, and the desired drive characteristics may not be obtained.

[0073] In contrast, in the actuator device 1, since the first connection region 372 includes the first curved portion 372c and the second connection region 382 includes the second curved portion 382c, when the fixing regions 371, 381 move due to the deformation of the wiring board 2, stress can be generated in a concentrated manner in the curved portions 372c, 382c. This is because the tensile stress or compressive stress acting on the metal board 3 via the fixing regions 371, 381 can be converted into bending stress acting on the curved portions 372c, 382c. In other words, the stress acting on the metal board 3 due to the deformation of the wiring board 2 is absorbed by the first connection region 372 and the second connection region 382, ​​which are unlikely to affect the change in the resonance frequency of the metal board 3, and the stress can be suppressed from acting on the first coupling portion 35, the second coupling portion 36, and the main body portion 31, which are likely to affect the change in the resonance frequency of the metal board 3.

[0074] In addition, in an example in which each connection region 372, 382 does not include each curved portion 372c, 382c, and a first curved portion bent toward the movable portion 32 side from the first extension portion 33 is provided closer to the main body portion 31 (one side in the Y-axis direction) than the connection portion between the first extension portion 33 and the first coupling portion 35, and a second curved portion bent toward the movable portion 32 side from the second extension portion 34 is provided closer to the main body portion 31 (one side in the Y-axis direction) than the connection portion between the second extension portion 34 and the second coupling portion 36, the following problem may occur. That is, in the above configuration, the connection portion between the first extension portion 33 and the first coupling portion 35 is located closer to the first fixing region 371 than the first curved portion, and the connection portion between the second extension portion 34 and the second coupling portion 36 is located closer to the second fixing region 381 than the second curved portion. Therefore, for example, if the wiring board 2 expands or contracts due to a change in the environmental temperature, unnecessary stress is likely to act on the connection portion between the first extension portion 33 and the first connecting portion 35, and the connection portion between the second extension portion 34 and the second connecting portion 36, resulting in a significant change in the resonant frequency of the metal board 3.

[0075] In contrast to this, in the actuator device 1, a first curved portion 372c is provided in a first connection region 372 located on the opposite side to the main body portion 31 (the other side in the Y-axis direction) from the connection portion between the first extension portion 33 and the first coupling portion 35, and a second curved portion 382c is provided in a second connection region 382 located on the opposite side to the main body portion 31 (the other side in the Y-axis direction) from the connection portion between the second extension portion 34 and the second coupling portion 36. This makes it possible to suppress significant fluctuations in the resonance frequency in both the leaf spring resonance mode and the movable portion resonance mode, and to stably obtain desired drive characteristics.

[0076] In addition, if, as viewed from the Z-axis direction, the outer edge of the first connection region 372 opposite to the movable part 32 extends along the Y-axis direction, and only the outer edge on the movable part 32 side is bent toward the movable part 32, and the outer edge of the second connection region 382 opposite to the movable part 32 extends along the Y-axis direction, and only the outer edge on the movable part 32 side is bent toward the movable part 32, the following problem may occur. That is, in this example, each connection region 372, 382 does not include a curved portion, and the width of the first connection region 372 in the X-axis direction increases as it approaches the first fixing region 371 from the first extension portion 33 side, and the width of the second connection region 382 in the X-axis direction increases as it approaches the second fixing region 381 from the second extension portion 34 side. Therefore, when the wiring board 2 expands or contracts, it becomes difficult to convert the tensile stress or compressive stress acting on the metal board 3 into bending stress. In contrast, in the actuator device 1, a first curved portion 372c is formed in the first connection region 372, where both the first outer edge P1 and the second outer edge P2 are bent toward the movable part 32, and a second curved portion 382c is formed in the second connection region 382, ​​where both the third outer edge P3 and the fourth outer edge P4 are bent toward the movable part 32. Therefore, when the wiring board 2 expands or contracts, the tensile stress or compressive stress acting on the metal substrate 3 can be effectively converted into bending stress acting on each curved portion 372c, 382c.

[0077] In the actuator device 1, the portion 372a extending linearly from the first extending portion 33 is connected to the first curved portion 372c, and the portion 372b extending linearly from the second extending portion 34 is connected to the second curved portion 382c. This makes it possible to suppress the influence of deformation of the curved portion 372c on the connection portion between the first extending portion 33 and the first connecting portion 35. Similarly, it is possible to suppress the influence of deformation of the curved portion 382c on the connection portion between the second extending portion 34 and the second connecting portion 36.

[0078] In the actuator device 1, the portion 372b, which has a positional relationship intersecting with the portion 372a and extends linearly from the first fixing region 371, is connected to the first curved portion 372c, and the portion 382b, which has a positional relationship intersecting with the portion 372b and extends linearly from the second fixing region 381, is connected to the second curved portion 382c. This allows the first curved portion 372c and the second curved portion 382c to be locally deformed in the first connection region 372 and the second connection region 382 when the wiring board 2 expands or contracts due to a change in the environmental temperature, for example. Therefore, the influence of the deformation of the curved portion 372c on the connection portion between the first extension portion 33 and the first connection portion 35 can be further suppressed. Similarly, the influence of the deformation of the curved portion 382c on the connection portion between the second extension portion 34 and the second connection portion 36 can be further suppressed. Furthermore, since each portion 372b, 382b has a shape extending in a straight line, the first curved portion 372c and the second curved portion 382c can be appropriately deformed both when the wiring board 2 expands due to a change in environmental temperature, and when the wiring board 2 contracts.

[0079] In the actuator device 1, when viewed from the Z-axis direction, the angle that the portion 372b forms with respect to the Y-axis direction is greater than 0 degrees and equal to or less than 90 degrees, and the angle that the portion 382b forms with respect to the Y-axis direction is greater than 0 degrees and equal to or less than 90 degrees. This allows the first curved portion 372c and the second curved portion 382c to be reliably deformed in the first connection region 372 and the second connection region 382 when the wiring board 2 expands or contracts due to a change in environmental temperature, for example. Specifically, the direction in which the portion 372b extends intersects with the above-mentioned direction in which the first fixing region 371 moves, and the direction in which the portion 382b extends intersects with the above-mentioned direction in which the second fixing region 381 moves, so that the curved portions 372c, 382c can be deformed according to the amount of deformation of the wiring board 2.

[0080] In the actuator device 1, when viewed from the Z-axis direction, the first outer edge P1 and the second outer edge P2 are each curved so as to be convex on the side opposite the movable part 32, and the third outer edge P3 and the fourth outer edge P4 are each curved so as to be convex on the side opposite the movable part 32. Thereby, when the wiring board 2 expands or contracts due to a change in the environmental temperature, for example, stress concentration in the first curved portion 372c and the second curved portion 382c is alleviated, thereby preventing damage to the first curved portion 372c and the second curved portion 382c.

[0081] In the actuator device 1, the first fixing region 371 and the second fixing region 381 are spaced apart from each other across the region Rh located on the opposite side of the main body portion 31 with respect to the movable portion 32 in the direction in which the main body portion 31 and the movable portion 32 are arranged. This reduces the risk of stray light being generated by the first fixing region 371 or the second fixing region 381 when light is irradiated onto the movable portion 32. In addition, even in the metal substrate 3 that is susceptible to the effects of the expansion and contraction of the wiring board 2 because the first fixing region 371 and the second fixing region 381 are spaced apart, the first curved portion 372c deforms in the first connection region 372 and the second curved portion 382c deforms in the second connection region 382, ​​so that a change in the resonance frequency of the metal substrate 3 can be suppressed. [Variations]

[0082] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-mentioned embodiments. For example, each of the fixing regions 371, the second fixing region 381, and the third fixing region 391 may be a region fixed to the wiring board 2. Each of the fixing regions 371, 381, and 391 may include, for example, only a region facing a portion of the wiring board 2 and fixed to the wiring board 2.

[0083] The shapes of the first connection region 372 and the second connection region 382 are not limited to those in the above embodiment. For example, when viewed from the Z-axis direction, the first outer edge P1 and the second outer edge P2 of the first curved portion 372c of the first connection region 372 may be bent in a V-shape so as to be convex on the opposite side to the movable portion 32. The third outer edge P3 and the fourth outer edge P4 of the second curved portion 382c of the second connection region 382 may also be bent in a V-shape so as to be convex on the opposite side to the movable portion 32. In addition, the angle θ1 that the portion 372b makes with respect to the Y-axis direction and the angle θ2 that the portion 382b makes with respect to the Y-axis direction may each be greater than 90 degrees, for example. In addition, for example, the first connection region 372 may not include the portion 372b, and the first curved portion 372c connected to the portion 372a may be directly connected to the first fixing region 371. The second connection region 382 may also not include the portion 382b, and the second curved portion 382c connected to the portion 382a may be directly connected to the second fixed region 381.

[0084] In the example shown in FIG. 8, the portion 372a extends along the Y-axis direction, and the portion 372b extends along the X-axis direction. The angle θ1 that the portion 372b makes with respect to the Y-axis direction is about 90 degrees. The portion 382b of the second connection region 382 may also have a configuration similar to that of the portion 372b shown in FIG. 8. For example, the portion 372a of the first connection region 372 may be inclined toward the movable portion 32 with respect to the first extension portion 33, and the portion 382a of the second connection region 382 may be inclined toward the movable portion 32 with respect to the second extension portion 34. For example, the first extension portion 33 may be inclined toward the movable portion 32 with respect to the Y-axis direction, and the portion 372a may be further inclined toward the movable portion 32 with respect to the first extension portion 33, and the second extension portion 34 may be inclined toward the movable portion 32 with respect to the Y-axis direction, and the portion 372b may be further inclined toward the movable portion 32 with respect to the second extension portion 34.

[0085] Also, the first connection region 372 may not include either the portion 372a or the portion 372b, for example, or may not include both the portion 372a and the portion 372b. Also, the second connection region 382 may not include either the portion 382a or the portion 382b, for example, or may not include both the portion 382a and the portion 382b, for example. As an example, the example shown in FIG. 9 differs from the above embodiment in that the first connection region 372 includes a first curved portion 372c that is continuous with each of the first extension portion 33 and the first fixed region 371. The first connection region 372 does not include the portion 372a or the portion 372b. The first curved portion 372c is curved between the first extension portion 33 and the first fixed region 371 so as to be convex toward the opposite side to the movable portion 32. The second connection region 382 may also have a similar configuration to the first connection region 372 shown in FIG.

[0086] In the above embodiment, the third connection part connected to the main body part is configured by one third connection part 39, but the third connection part may be configured by a plurality of third connection parts 39. As an example, the third connection part may be configured by two third connection parts 39, and the two third connection parts 39 may be located on one side in the Y-axis direction with respect to the main body part 31, and may be arranged line-symmetrically with respect to a straight line passing through the center of the optical surface 51 along the Y-axis direction.

[0087] The shape of the metal substrate 3 is not limited to the above embodiment. For example, the first fixing region 371 and the second fixing region 381 may be connected to each other. Even in this case, the thickness of the wiring substrate 2 is overwhelmingly larger than the thickness of the metal substrate 3, and the difference in thermal expansion coefficient between the wiring substrate 2 and the metal substrate 3 is large, so that the metal substrate 3 is subjected to tensile stress or compressive stress. However, as described above, the first curved portion 372c is provided in the connection region 372, and the second curved portion 382c is provided in the connection region 382, ​​so that the desired driving characteristics can be stably obtained.

[0088] Also, for example, the third fixing region 391 and the first fixing region 371 of the metal substrate 3 may be connected to each other, and the third fixing region 391 and the second fixing region 381 may be connected to each other. In the example shown in FIG. 10, the metal substrate 3 further includes a first intermediate portion 30a and a second intermediate portion 30b. The first intermediate portion 30a is connected to the first fixing region 371 and the third fixing region 391. The first intermediate portion 30a includes a portion facing a part of the wiring substrate 2. Note that, in the example shown in FIG. 10, the wiring substrate 2 and the like are omitted from the illustration. As an example, the first intermediate portion 30a has a C-shape surrounding the main body portion 31 when viewed from the Z-axis direction. The second intermediate portion 30b is connected to the second fixing region 381 and the third fixing region 391. The second intermediate portion 30b includes a portion facing a part of the wiring substrate 2. As an example, the second intermediate portion 30b has a C-shape surrounding the main body portion 31 when viewed from the Z-axis direction. According to this modification, the handleability of the metal substrate 3 during the manufacture of the actuator device 1 can be improved. In this modification, for example, the first adhesive member 4 may be disposed between the first intermediate portion 30a and a portion of the wiring substrate 2 facing the first intermediate portion 30a, and between the second intermediate portion 30b and a portion of the wiring substrate 2 facing the second intermediate portion 30b, and all of the fixing regions 371, 381, 391, the first intermediate portion 30a, and the second intermediate portion 30b may be fixed to the wiring substrate 2. This can increase the adhesive strength between the wiring substrate 2 and the metal substrate 3. In addition, in this modification, for example, only the fixing regions 371, 381, 391 may be fixed to the wiring substrate 2.

[0089] The shape of the wiring board 2 is not limited to that of the above embodiment. For example, the wiring board 2 may have a recess in which the central portion is recessed on the opposite side of the metal board 3 with respect to the mounting surface 2a instead of the opening. In that case, each of the second region R2 and the third region R3 may face the recess of the wiring board 2. Also, for example, the wiring board 2 may have a plurality of pillars instead of the opening. In that case, each of the second region R2 and the third region R3 may face the wiring board 2. Also, in the above embodiment, the wiring board 2 supporting the metal board 3 is exemplified, but the metal board 3 may be supported by a support composed of, for example, a single member or a plurality of members.

[0090] In the above embodiment, torsional vibration (torsional resonance) is induced in the first connecting portion 35 and the second connecting portion 36, and the movable portion 32 oscillates around the X-axis, but the manner of operation of the movable portion 32 is not particularly limited. As an example, in the actuator device 1, in addition to the mode in which the movable portion 32 and the optical surface 51 oscillate (hereinafter referred to as the "first resonance mode"), or instead of the first resonance mode, there may be a mode in which the movable portion 32 moves along the Z-axis direction by the generation of periodic plate waves, causing the first connecting portion 35 and the second connecting portion 36 to move (translate) along the Z-axis direction (hereinafter referred to as the "second resonance mode"). In that case, in the first resonance mode, the oscillation angle and phase of the movable portion 32 may be detected by the detection piezoelectric element 7, and in the second resonance mode, the displacement amount and phase of the movable portion 32 may be detected by the detection piezoelectric element 7.

[0091] In the above embodiment, the optical function unit 5 has the optical surface 51 which is a mirror surface, but the optical function unit 5 may be, for example, a reflective diffraction grating, a transmission diffraction grating, an optical filter, or the like. In the above embodiment, the driving piezoelectric element 6 is disposed on the mounting surface 31a of the metal substrate 3, and the detecting piezoelectric element 7 is disposed on the driving piezoelectric element 6. However, the detecting piezoelectric element 7 may be disposed on the mounting surface 31a of the metal substrate 3, and the driving piezoelectric element 6 may be disposed on the detecting piezoelectric element 7. In the above embodiment, the actuator device 1 includes the driving piezoelectric element 6 as a vibration element, but the vibration element may be any element having a vibration source which vibrates by a drive signal, and is not limited to a piezoelectric driving type. For example, the vibration element may be an electromagnetic driving type having a magnet in the main body 31 of the metal substrate 3 and a coil in a location separate from the metal substrate 3 (or having a coil in the main body 31 of the metal substrate 3 and a magnet in a location separate from the metal substrate 3). The actuator device 1 only needs to include the wiring board 2, the metal board 3, and the driving piezoelectric element 6. The actuator device 1 may not, for example, be provided with the connector 24, the wires 11, and the wires 12. The actuator device 1 may not, for example, be provided with the first adhesive member 4 and the second adhesive member 8, and may not, for example, be provided with the detecting piezoelectric element 7. [Explanation of symbols]

[0092] 1...actuator device, 2...wiring board (support), 3...metal board, 6...driving piezoelectric element (vibration element), 30a...first intermediate portion, 30b...second intermediate portion, 31...main body portion, 32...movable portion, 33...first extension portion, 34...second extension portion, 35...first coupling portion, 36...second coupling portion, 37...first connection portion, 38...second connection portion, 39...third connection portion, 371...first fixed region, 372...first connection region, 3 72a... part (first part), 372b... part (third part), 372c... first song part, 381... second fixed area, 382... second connection area, 382a... part (second part), 382b... part (fourth part) 382c...Second music part, 391...Third fixed area, 392...Third connection area, P1...First outer edge, P2...Second outer edge, P3...Third outer edge, P4...Fourth outer edge, Rh...Area, θ1, θ2...Angle.

Claims

1. A support; A metal substrate supported by the support; a vibration element disposed in a main body portion of the metal substrate; The metal substrate is A movable part; a first extension portion and a second extension portion extending from the main body portion such that the movable portion is located therebetween; a first connecting portion that connects the first extending portion and the movable portion; a second connecting portion that connects the second extending portion and the movable portion; A first connection portion connected to the first extension portion; A second connection portion connected to the second extension portion; A third connection portion connected to the main body portion, The first connection portion is A first fixing region fixed to the support; a first connection region connected to the first extension portion and the first fixing region, The second connection portion is A second fixing region fixed to the support; a second connection region connected to the second extension portion and the second fixing region, The third connection portion is a third fixing region fixed to the support; a third connection region connected to the body portion and the third fixing region, the first connection region includes a first curved portion; the second connection region includes a second curved portion; the first curved portion has a first outer edge on a side of the movable portion and a second outer edge on a side opposite to the movable portion, the second curved portion has a third outer edge on the movable portion side and a fourth outer edge on the opposite side to the movable portion, each of the first outer edge and the second outer edge is bent toward the movable portion when viewed from a thickness direction of the metal substrate; An actuator device, wherein the third outer edge and the fourth outer edge are each bent toward the movable portion when viewed in a thickness direction of the metal substrate.

2. The first connection region further includes a first portion linearly extending from the first extension portion, The second connection region further includes a second portion extending linearly from the second extension portion, the first portion is connected to the first curved portion; The actuator device of claim 1 , wherein the second portion is connected to the second curved portion.

3. The first connection region further includes a third portion extending linearly from the first fixing region, The second connection region further includes a fourth portion extending linearly from the second fixing region, the third portion has a positional relationship intersecting with the first portion and is connected to the first curved portion; The actuator device according to claim 2 , wherein the fourth portion has an intersecting positional relationship with the second portion and is connected to the second curved portion.

4. When viewed from a thickness direction of the metal substrate, an angle formed by the third portion with respect to a direction in which the main body portion and the movable portion are arranged is greater than 0 degrees and is equal to or smaller than 90 degrees; The actuator device according to claim 3 , wherein when viewed from a thickness direction of the metal substrate, an angle formed by the fourth portion with respect to the direction in which the main body portion and the movable portion are aligned is greater than 0 degrees and is equal to or smaller than 90 degrees.

5. When viewed from a thickness direction of the metal substrate, each of the first outer edge and the second outer edge is curved so as to be convex toward an opposite side to the movable portion, An actuator device according to any one of claims 1 to 4, wherein, when viewed in the thickness direction of the metal substrate, each of the third outer edge and the fourth outer edge is curved so as to be convex toward the opposite side to the movable portion.

6. An actuator device according to any one of claims 1 to 5, wherein the first fixing region and the second fixing region are spaced apart from each other by a region located on the opposite side of the main body portion with respect to the movable portion in the direction in which the main body portion and the movable portion are arranged.

7. The metal substrate is a first intermediate portion connected to the third fixing region and the first fixing region; The actuator device according to claim 1 , further comprising: a second intermediate portion connected to the third fixing region and the second fixing region.

Citation Information

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