Optical unit, optical device, and method for manufacturing optical unit

Abstract

The present invention provides an optical unit comprising: a metal base having a main surface and a back surface on the opposite side of the main surface; an optical surface provided on the main surface; and a vibration element provided on the main surface or the back surface, the substrate including: a support portion; a first extension portion and a second extension portion extending from the support portion; a movable part disposed between the first extension part and the second extension part; and a first connecting portion that connects the first extension portion and the movable portion, and a second connecting portion that connects the second extension portion and the movable portion. The vibration element is provided on the support portion. And an optical surface provided on the main surface in the movable part and configured to oscillate the movable part by causing the supporting part to oscillate to cause torsional vibration in the first connecting part and the second connecting part.

Description

[0001] This application is a divisional application of a patent application with an application date of October 1, 2020 and an application number of 202080093051.7 and an invention title of Optical unit Optical device, and method of manufacturing the optical unit Technical Field

[0002] The present disclosure relates to an optical unit, an optical device, and a method for manufacturing an optical unit. Background Art

[0003] Patent Document 1 describes an optical scanning device having a mirror vibration unit. The mirror vibration unit includes a substrate and a piezoelectric element provided on the substrate. A mirror unit is mounted on the substrate via a torsion beam. In addition, an oscillator and a torsion beam supporting the oscillator are formed outside the mirror unit and the torsion beam supporting it. The mirror unit and the oscillator constitute two oscillator systems and are designed to have resonance frequencies f and 2f, or f and 3f. The piezoelectric element is connected to a drive circuit with a variable frequency. In this mirror vibration unit, by applying a voltage to the piezoelectric element, the piezoelectric element expands and contracts, thereby generating a plate wave on the substrate. The vibration energy of this plate wave causes the mirror unit supported by the beam to swing, providing torque to the mirror unit.

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2010-2783 Summary of the Invention

[0007] Technical Problem to be Solved by the Invention

[0008] However, in an optical device such as the optical scanning device described above, when a metal plate is used as the substrate, the light used for scanning may be reflected other than by the mirror unit and become stray light. The generation of stray light may be a cause of deterioration of the optical characteristics of the optical scanning device.

[0009] Therefore, an object of the present disclosure is to provide an optical unit, an optical device, and a method for manufacturing an optical unit that can improve optical characteristics.

[0010] Technical Means for Solving the Problem

[0011] ​The optical unit of the present disclosure includes: a base body made of metal, having a main surface and a back surface opposite to the main surface; an optical surface provided on the main surface; and a vibration element provided on the main surface or the back surface. The base body includes: a support portion; a first extension portion and a second extension portion extending from the support portion; a movable portion disposed between the first extension portion and the second extension portion; a first connection portion connecting the first extension portion and the movable portion, and a second connection portion connecting the second extension portion and the movable portion. The vibration element is provided on the support portion, and by vibrating the support portion, torsional vibration is generated in the first connection portion and the second connection portion to swing the movable portion. The optical surface is provided on the main surface in the movable portion, and a frosted surface is formed on at least a part of at least any one of a first region on the main surface of the support portion closer to the movable portion than the position where the vibration element is provided, a second region on the main surface corresponding to the first extension portion and the second extension portion, and a third region on the main surface or the back surface opposed to the vibration element.

[0012] In this optical unit, the vibration element provided on the support portion of the base body generates torsional vibration in the first connection portion and the second connection portion of the base body, causing the movable portion provided with the optical surface to swing. Therefore, by making light incident on the optical surface swung by the movable portion, various optical functions such as light scanning can be achieved. In particular, in this optical unit, a frosted surface is formed on at least a part of at least any one of a first region on the main surface of the base body where the optical surface is provided, closer to the movable portion than the position where the vibration element is provided, a second region corresponding to the first extension portion and the second extension portion, and a third region on the main surface or the back surface opposed to the vibration element. The first region and the second region are regions on the main surface relatively close to the optical surface (movable portion) where light is likely to be incident. Therefore, when a frosted surface is formed in the first region and / or the second region, the generation of stray light can be suppressed. That is, the optical characteristics are improved. In addition, when a frosted surface is formed in the third region, the bonding of the vibration element to the main surface or the back surface is strengthened. By firmly bonding the vibration element to the main surface or the back surface, torsional vibration can be reliably generated in the first connection portion and the second connection portion to swing the optical surface (movable portion). Thus, the optical characteristics are also improved in this case.

[0013] In the optical unit of the present disclosure, it may also be that the vibration element is provided on the main surface, and a frosted surface is formed in the first region, the second region, and the third region. In this case, the optical characteristics are reliably improved.

[0014] In the optical unit of the present disclosure, it may also be that a frosted surface is formed on the entire main surface. In this case, the optical characteristics are more reliably improved. In addition, in this case, when forming the frosted surface, the entire main surface can be roughened together, so the manufacturing becomes easy.

[0015] In the optical unit of the present disclosure, alternatively, the substrate may have side surfaces connecting the main surface and the back surface, and a matte surface may be formed on the entire back surface and the side surfaces. In this case, the optical characteristics can be further reliably improved. Further, in this case, when forming the matte surface, the entire surface of the substrate including the main surface, the back surface, and the side surfaces can be roughened together, so that the manufacturing becomes easier.

[0016] In the optical unit of the present disclosure, alternatively, the substrate may have side surfaces connecting the main surface and the back surface, and at least a part of the side surfaces may be flat surfaces. In this case, the strength is improved.

[0017] In the optical unit of the present disclosure, alternatively, it may include stress relief portions provided between the optical surface and the first connection portion and between the optical surface and the second connection portion for relieving stress caused by the torsion of the first connection portion and the second connection portion. In this case, since the deflection of the movable portion is suppressed, the optical characteristics are further improved.

[0018] In the optical unit of the present disclosure, alternatively, it may further include an electrode for electrically connecting the vibration element to the outside. The electrode is located on the support portion and the vibration element, and includes a first portion in contact with the vibration element and a second portion provided on the support portion so as to extend from the first portion toward the outer edge of the support portion. In this case, by providing wiring such as a lead wire in the second portion of the electrode extending toward the outer edge of the support portion, the vibration element can be electrically connected to the outside via the electrode. Therefore, compared with the case where wiring such as a lead wire is directly extended from the outside to the vibration element, the wiring such as a lead wire is shortened and can be stably connected. Further, the outside here refers to a structure outside the optical unit, and in an optical device including the optical unit, it may be a structure inside the optical device such as a substrate on which the optical unit is mounted.

[0019] The optical device of the present disclosure includes: the above-described optical unit; a light source for outputting light; and a detector configured on the optical axis of the light output from the light source for detecting the light. The light source and the detector are configured such that due to the displacement of the substrate corresponding to the vibration of the vibration element, interference occurs between the optical axis and a part of the substrate. According to this optical device, the amplitude (swing angle) of the swing of the optical surface (movable portion) can be detected based on the output of the light output from the light source and detected by the detector without being blocked by the substrate.

[0020] The optical device of the present disclosure includes: an optical unit including a substrate made of metal, an optical surface provided on the substrate, and a vibration element provided on the substrate; and a container that houses the optical unit. The substrate includes: a support portion; a first extension portion and a second extension portion extending from the support portion; a movable portion disposed between the first extension portion and the second extension portion; a first connection portion that connects the first extension portion and the movable portion; and a second connection portion that connects the second extension portion and the movable portion. The vibration element is provided on the support portion, and by vibrating the support portion, torsional vibrations are generated in the first connection portion and the second connection portion to swing the movable portion. The optical surface is provided on the movable portion, and the container is provided with an opening for allowing light to enter the optical surface. At least a part of the portion of the substrate that is exposed from the container through the opening is formed with a matte surface.

[0021] In this optical device, the vibration element provided on the support portion of the substrate generates torsional vibrations in the first connection portion and the second connection portion of the substrate, causing the movable portion provided with the optical surface to swing. Therefore, by allowing light to enter the optical surface that swings with the movable portion, various optical functions such as optical scanning can be achieved. In particular, in this optical device, at least a part of the portion of the substrate that is exposed from the container through the opening is formed with a matte surface. The portion of the substrate that is exposed from the container through the opening is a portion where light is likely to enter. Thus, the generation of stray light can be suppressed. That is, the optical characteristics are improved.

[0022] A method for manufacturing the optical unit of the present disclosure includes: a first step of preparing a metal component; a second step of, after the first step, forming a substrate having a main surface and a back surface opposite to the main surface from the metal component; and a third step of, after the second step, roughening at least a part of the substrate. The substrate includes: a support portion for setting a vibration element; a first extension portion and a second extension portion extending from the support portion; a movable portion disposed between the first extension portion and the second extension portion, and the main surface side is for setting an optical surface; a first connection portion that connects the first extension portion and the movable portion; and a second connection portion that connects the second extension portion and the movable portion. In the third step, at least a part of at least any one of a first region on the main surface of the support portion that is closer to the movable portion than the position where the vibration element is set, a second region on the main surface corresponding to the first extension portion and the second extension portion, and a third region on the main surface or the back surface that faces the vibration element is roughened.

[0023] Alternatively, a method for manufacturing an optical unit of the present disclosure includes: a first step of preparing a metal component; a second step of roughening the surface of the metal component after the first step; and a third step of forming, after the second step, a substrate having a roughened main surface and a roughened back surface opposite to the main surface from the metal component, the substrate including: a support portion for disposing a vibration element; a first extension portion and a second extension portion extending from the support portion; a movable portion disposed between the first extension portion and the second extension portion, and an optical surface is disposed on the main surface side; and a first connection portion connecting the first extension portion and the movable portion and a second connection portion connecting the second extension portion and the movable portion.

[0024] For the reasons described above, any of these manufacturing methods can manufacture an optical unit with improved optical characteristics.

[0025] Advantages of the Invention

[0026] According to the present disclosure, it is possible to provide an optical unit, an optical device, and a method for manufacturing an optical unit that can improve optical characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a perspective view showing the optical device of the present embodiment.

[0028] Figure 2 is a Figure 1 perspective view showing a part (cover portion) of the optical device shown omitted.

[0029] Figure 3 is a Figure 1 and Figure 2 plan view showing the optical unit shown.

[0030] Figure 4 is a cross-sectional view taken along the line IV-IV of Figure 3 .

[0031] Figure 5 is a Figure 3 , 4 perspective view showing a step of the method for manufacturing the optical unit shown.

[0032] Figure 6 is a Figure 3 , 4 perspective view showing a step of the method for manufacturing the optical unit shown.

[0033] Figure 7 is a Figure 3 , 4 perspective view showing a step of the method for manufacturing the optical unit shown.

[0034] Figure 8It is a diagram showing an optical unit of a first modified example.

[0035] Figure 9 It is Figure 8 a perspective view showing a step of a manufacturing method of the optical unit shown.

[0036] Figure 10 It is Figure 8 a perspective view showing a step of a manufacturing method of the optical unit shown.

[0037] Figure 11 It is Figure 8 a perspective view showing a step of a manufacturing method of the optical unit shown.

[0038] Figure 12 It is a plan view showing an optical unit of a second modified example.

[0039] Figure 13 It is Figure 12 a plan view showing a modified example of a stress relaxation portion and a setting portion shown.

[0040] Figure 14 It is a plan view showing an optical unit of a third modified example.

[0041] Figure 15 It is a plan view showing an optical unit of a fourth modified example.

[0042] Figure 16 It is a plan view showing an optical unit of a fifth modified example.

[0043] Figure 17 It is a cross-sectional view taken along line VII-VII of Figure 16 .

[0044] Figure 18 It is a plan view showing an optical unit of a sixth modified example.

[0045] Figure 19 It is a plan view showing an optical unit of a seventh modified example.

[0046] Figure 20 It is a perspective view showing an optical device of a first modified example.

[0047] Figure 21 It is a perspective view showing an optical device of a second modified example.

[0048] Figure 22 It is a perspective view showing an optical device of a third modified example. Detailed implementation mode

[0049] A detailed description of an embodiment of the present disclosure will be given below with reference to the accompanying drawings. In addition, in each figure, the same elements or equivalent elements to each other are denoted by the same reference numerals, and redundant descriptions may sometimes be omitted. In addition, a rectangular coordinate system defined by the X-axis, Y-axis, and Z-axis may sometimes be indicated in each figure.

[0050] Figure 1 is a perspective view showing the optical device of the present embodiment. Figure 2 is Figure 1 a perspective view showing a part (cover) of the optical device shown in Figure 1 omitted. As shown in 2 , the optical device 100 includes an optical unit 1 and a container 110 that houses the optical unit 1. The container 110 has a main body 111 and a cover 112. As an example, the main body 111 is in the shape of a rectangular box open on one side. A notch 111r is formed in one side wall of the main body 111.

[0051] The cover 112 is disposed on the main body 111 so as to close the open portion of the main body 111, and is attached to the main body 111 by fixing members 114 such as screws. An opening 112r is formed in the cover 112. Here, the opening 112r is sealed by a window member 113 made of a light-transmitting material. The window member 113 is parallel to the optical surface 20s and / or the main surface 5s described later. In addition, the opening 112r may be open without providing the window member 113.

[0052] The optical device 100 further includes a wiring board 115. The wiring board 115 is disposed inside the main body 111 on the side of the side wall where the notch 111r is formed, and is fixed to the main body 111. Electrodes 40 such as pads and a connector 50 are provided on the wiring board 115. The electrode 40 is electrically connected to an electrode (the upper electrode 31 of the vibration element 30 described later) of the optical unit 1 via a wiring 41 such as a wire. On the wiring board 115, wirings (not shown) for electrically connecting the electrode 40 to the connector 50 and wirings (not shown) for electrically connecting the other electrode (the lower electrode 32 of the vibration element 30 described later) of the optical unit 1 to the connector 50 are provided.

[0053] That is, the connector 50 is electrically connected to the vibration element 30 of the optical unit 1. A drive voltage can be supplied to the vibration element 30 from the outside of the optical device 100 via the connector 50. Next, the optical unit 1 will be described.

[0054] Figure 3 is a plan view showing Figure 1 , 2 the optical unit shown in Figure 4 is a cross-sectional view taken along line IV-IV of Figure 3 . In particular, Figure 4 in (b) isFigure 4 An enlarged view of the region AR in (a). As Figure 3 , 4 shown, the optical unit 1 includes a substrate 5, an optical surface 20s, and a vibration element 30. The substrate 5 is made of a metal such as an iron-based, stainless steel-based, copper-based, permalloy-based, titanium-based, tungsten-based, molybdenum-based metal, and has a plate shape. The substrate 5 has a main surface 5s, a back surface 5r on the opposite side of the main surface 5s, and side surfaces 5f connecting the main surface 5s and the back surface 5r to each other. Here, the direction from the back surface 5r to the main surface 5s (the thickness direction of the substrate 5) is set as the Z-axis direction. The optical surface 20s and the vibration element 30 are provided on the main surface 5s of the substrate 5 here.

[0055] The substrate 5 includes a support portion 10, a first extension portion 11, a second extension portion 12, a first connection portion 13, a second connection portion 14, and a movable portion 15. The support portion 10, the first extension portion 11, the second extension portion 12, the first connection portion 13, the second connection portion 14, and the movable portion 15 are formed integrally with each other, and each includes a part of the main surface 5s, the back surface 5r, and the side surface 5f. The support portion 10 has a rectangular plate shape here. The first extension portion 11 and the second extension portion 12 extend from one end portion (here, in one direction) of the support portion 10 at intervals from each other.

[0056] As an example, the first extension portion 11 and the second extension portion 12 have the same shape as each other, and extend parallel to each other in such a manner that the intervals therebetween in the Y-axis direction are constant. Here, the extension direction of the first extension portion 11 and the second extension portion 12 is set as the X-axis direction, and the direction in which the first extension portion 11 faces the second extension portion 12 is set as the Y-axis direction. The first extension portion 11 and the second extension portion 12 have, for example, an elongated rectangular plate shape (rod shape with a rectangular cross section). Here, the first extension portion 11 and the second extension portion 12 are supported by the support portion 10 only at one end portion in the X-axis direction, and constitute a cantilever. In addition, the first extension portion 11 and the second extension portion 12 may also have portions extending in a direction intersecting the X-axis direction.

[0057] The movable portion 15 is disposed between the first extension portion 11 and the second extension portion 12. More specifically, the movable portion 15 is disposed at an intermediate position between the first extension portion 11 and the second extension portion 12 in the Y-axis direction. The movable portion 15 has a disk shape here, but may be formed into any shape according to the shape of the optical surface 20s, for example.

[0058] The first connecting portion 13 extends from the first extension portion 11 in the Y-axis direction and is connected to the movable portion 15. Thus, the first connecting portion 13 connects the first extension portion 11 and the movable portion 15 to each other. The second connecting portion 14 extends from the second extension portion 12 in the Y-axis direction and is connected to the movable portion 15. Thus, the second connecting portion 14 connects the second extension portion 12 and the movable portion 15 to each other. Here, the first connecting portion 13 and the second connecting portion 14 are provided at the same position in the X-axis direction of the first extension portion 11 and the second extension portion 12. The first connecting portion 13 and the second connecting portion 14 are located on a single straight line in the Y-axis direction. According to the positional relationship among the first extension portion 11, the second extension portion 12, and the movable portion 15 described above, the length of the first connecting portion 13 in the Y-axis direction is the same as the length of the second connecting portion 14 in the Y-axis direction. Here, the first connecting portion 13 and the second connecting portion 14 have the same shape.

[0059] The first connecting portion 13 and the second connecting portion 14 are formed in the shape of an elongated rectangular plate (rod-shaped with a rectangular cross-section) here. As will be described later, the first connecting portion 13 and the second connecting portion 14 function as torsion bars that elastically deform in a torsional manner as the first extension portion 11 and the second extension portion 12 deform (displace). The movable portion 15 is supported via the first connecting portion 13 and the second connecting portion 14 and swings (is supported to be swingable) about an axis in the Y-axis direction as the first connecting portion 13 and the second connecting portion 14 elastically deform.

[0060] The optical unit 1 further includes an optical component 20. The optical component 20 is formed in a disk shape here, and one surface is the optical surface 20s. The optical component 20 is mounted on the movable portion 15 such that the surface opposite to the optical surface 20s faces the main surface 5s, that is, the optical surface 20s faces the side opposite to the main surface 5s. Thus, in the optical unit 1, the optical surface 20s is provided on the movable portion 15. The optical surface 20s (the center of the optical surface 20s) is disposed at an intermediate position between the first extension portion 11 and the second extension portion 12 in the Y-axis direction. Here, the base 5 and the optical surface 20s are line-symmetric with respect to a straight line passing through the center of the optical surface 20s and extending in the X-axis direction. The optical surface 20s is, for example, a reflecting mirror surface (reflective surface). In this case, the optical component 20 is formed of, for example, a semiconductor material such as silicon or glass, and the optical surface 20s is formed by forming a reflective film on one surface. In addition, the reflective film on one surface of the optical component 20 can be omitted. That is, one surface of the optical component 20 itself can also be used as the optical surface 20s.

[0061] The vibration element 30 is provided on the support portion 10. Here, the vibration element 30 is provided on the main surface 5s. An upper electrode 31 is provided on the surface of the vibration element 30 opposite to the main surface 5s. A lower electrode 32 is provided between the vibration element 30 and the main surface 5s. The upper electrode 31 is in contact (electrically connected) with the vibration element 30. Here, the lower electrode 32 is in contact (electrically connected) with the vibration element 30 and the support portion 10. That is, the vibration element 30 is joined to the main surface 5s through the lower electrode 32. However, a conductive adhesive layer may be provided between the main surface 5s and the lower electrode 32 and / or between the lower electrode 32 and the vibration element 30. In this case, the conductive adhesive layer contributes to the joining of the vibration element 30 and the main surface 5s.

[0062] In this way, here, the vibration element 30 is electrically connected to the base 5 via the lower electrode 32 (and the conductive adhesive layer). The base 5 (i.e., the optical unit 1) is fixed to the wiring board 115, for example, by a conductive adhesive layer or mechanical fixing, and is electrically connected to the wiring connected to the connector 50 on the wiring board 115. That is, the vibration element 30 is electrically connected to the connector 50 via the upper electrode 31, the wiring 41, the electrode 40, and the wiring board 115. Also, the vibration element 30 is electrically connected to the connector 50 via the lower electrode 32 (and the conductive adhesive layer) and the wiring board 115. Therefore, the upper electrode 31 and the lower electrode 32 are used for the electrical connection of the vibration element 30 to the outside (outside the optical unit 1).

[0063] Thereby, the vibration element 30 deforms and / or vibrates according to the drive voltage supplied from the outside via the connector 50, thereby vibrating the support portion 10. Thereby, the vibration element 30 causes torsional vibration (torsional resonance) in the first connection portion 13 and the second connection portion 14 via the vibration of the support portion 10, and swings the movable portion 15 and the optical surface 20s. That is, in the optical unit 1, the torsional resonance system of the first connection portion 13, the second connection portion 14, the movable portion 15, and the optical component 20 and the vibration element 30 are arranged at separate positions, and at the same time, a Lamb wave resonance structure is adopted, whereby torsional resonance can be generated with high drive efficiency.

[0064] The vibration element 30 is provided on the support portion 10 in such a manner that the center of the vibration element 30 coincides with the centers of the movable portion 15 and the optical surface 20s in the Y-axis direction. That is, the vibration element 30 is arranged at an intermediate position between the first extension portion 11 and the second extension portion 12 in the Y-axis direction. The position of the vibration element 30 in the X-axis direction can be arbitrarily set according to the form of the torsional vibration to be caused. The vibration element 30 is constituted by a piezoelectric body, for example.

[0065] In the optical device 100 described above, light (such as laser light) enters the container 110 through the window member 113 and the opening 112r of the cover 112. The light entering the container 110 is reflected by the optical surface 20s and exits to the outside through the window member 113 and the opening 112r. The optical surface 20s swings periodically. Therefore, the direction of light exiting from the container 110 changes periodically and continuously with the swing of the optical surface 20s. Thus, the optical device 100 can function as a light scanning device. In this case, the scanning direction of the light is the X-axis direction.

[0066] Here, in the optical unit 1, at least a part of at least any one of a first region R1 on the main surface 5s on the movable portion 15 side with respect to the position where the vibration element 30 is provided on the support portion 10, a second region R2 on the main surface 5s corresponding to the first extension portion 11 and the second extension portion 12, and a third region R3 on the main surface 5s opposed to the vibration element 30 is formed with a dimpled surface (matte surface). The first region R1 is a region that is bounded by a straight line L1 passing through the outer edge on the movable portion 15 side of the vibration element 30 and is on the movable portion 15 side (the positive side in the X-axis direction) with respect to the straight line L1. The second region R2 is one surface of the first extension portion 11 and the second extension portion 12. The third region R3 is a region that coincides with the vibration element 30 when viewed from the Z-axis direction.

[0067] In the present embodiment, a dimpled surface is formed on the entire first region R1, second region R2, and third region R3. More specifically, here, a dimpled surface (the region of the side surface 5f where the dimpled surface is formed will be described later) is formed on at least a part of the entire main surface 5s, the entire back surface 5r, and the side surface 5f. That is, here, in addition to the above-described first region R1 to third region R3, a dimpled surface is also formed in a region on the main surface 5s corresponding to the first connecting portion 13 and the second connecting portion 14 and a region on the main surface 5s corresponding to the movable portion 15.

[0068] In addition, as an example, the dimpled surface here refers to a surface with a surface roughness Ra greater than 0.4 (μm). Alternatively, the dimpled surface here may be a surface that has been roughened so that the surface roughness Ra is 6.3 (μm) or more. On the other hand, a surface with a surface roughness Ra less than 6.3 (μm) is sometimes referred to as a flat surface. Moreover, a surface with a surface roughness Ra of 0.4 (μm) or less can be a mirror surface. The height or pitch of the irregularities, etc. on the dimpled surface can be regular or irregular. Alternatively, the irregularities, etc. on the dimpled surface may or may not have a directionality.

[0069] Next, a method for manufacturing the above-described optical unit 1 will be described. Figures 5 to 7 It represents Figure 3 , 4 A perspective view of a step of the manufacturing method of the optical unit shown. In this manufacturing method, first, asFigure 5 As shown in (a) of , prepare a rectangular plate-shaped metal plate (metal component) 5A (first step). The metal plate 5A has a main surface 5As, a back surface 5Ar on the side opposite to the main surface 5As, and side surfaces 5Af connecting the main surface 5As and the back surface 5Ar to each other.

[0070] Next, as Figure 5 shown in (b) of , roughen at least a part of the surface (main surface 5As, back surface 5Ar, and side surfaces 5Af) of the metal plate 5A to form a metal plate 5B (second step). Here, as an example, the metal plate 5B is formed by roughening the entire surface of the metal plate 5A. The metal plate 5B has a roughened main surface 5Bs, a back surface 5Br, and side surfaces 5Bf. Examples of the roughening method include laser ablation, etching, or mechanical polishing. Here, since the entire surface of the metal plate 5A is roughened at once, as a roughening method, a method of immersing the entire metal plate 5A in an etching solution for etching can be used (it can also be other methods). In addition, the roughening here means forming the above-mentioned orange peel surface.

[0071] Next, as Figure 6 shown in (a) of , remove (cut out) a part of the metal plate 5B to form a metal plate 5C including a plurality (three here) of substrates 5 (third step). Each of the substrates 5 is a part 1A that will later become the optical unit 1. As a method of removing a part of the metal plate 5B, stamping or etching can be used. The substrate 5 includes a roughened (i.e., formed with an orange peel surface) main surface 5s, a back surface 5r, and a partially roughened side surface 5f. In the side surface 5f, the region that was originally the side surface 5Bf of the metal plate 5B is roughened to form an orange peel surface, and the newly formed region in this third step is not roughened and is a flat surface.

[0072] That is, in the optical unit 1 manufactured by this manufacturing method, at least a part of the side surface 5f is a flat surface. The region of the side surface 5f that is a flat surface is the region of the support portion 10 facing the movable portion 15 side, the region where the first extension portion 11 and the second extension portion 12 face each other, the regions corresponding to the two side surfaces of the first connection portion 13 and the second connection portion 14, and the regions corresponding to the outer side surfaces of the movable portion 15.

[0073] In addition, the order of the second step and the third step can be reversed. In this case, after removing a part of the metal plate 5A to form a metal plate 5C including a plurality of substrates 5 from the metal plate 5A, at least a part of the surface of the metal plate 5C is roughened. At this time, when the entire surface of the metal plate 5C is roughened together, the entire side surface 5f of the substrate 5 is roughened. That is, in the optical unit 1 manufactured in this case, a dimpled surface is formed on the entire side surface 5f. On the other hand, when roughening a part of the surface of the metal plate 5C, at least a part of at least any one of the first region R1, the second region R2, and the third region R3 in the main surface 5s of the substrate 5 can be selectively roughened. For example, laser ablation can be used as a method for selective roughening.

[0074] In subsequent steps, as Figure 6 shown in (b) of, a vibration element 30 (and an upper electrode 31 and a lower electrode 32) is formed on the support portion 10 of each substrate 5 (fourth step). Thereby, a plate member 5D including a plurality of units 1B each composed of a substrate 5 and a vibration element 30 is formed. When the vibration element 30 is a piezoelectric body, as a method for forming the piezoelectric body, for example, a printing method, pasting a piezoelectric sheet, film formation and patterning by a vapor growth method, or film formation and patterning by a liquid growth method can be used.

[0075] Next, as Figure 7 shown in (a) of, an optical surface 20s is provided on the movable portion 15 of each substrate 5 (fifth step). Here, the optical surface 20s is provided on the movable portion 15 by mounting an optical member 20 including the optical surface 20s on the movable portion 15. Thereby, a plate member 5E including a plurality of optical units 1 is formed. In addition, the order of the fourth step and the fifth step can be reversed.

[0076] After that, as Figure 7 shown in (b) of, by cutting each optical unit 1 (sixth step), a singulated optical unit 1 is obtained. In addition, the order of the fifth step and the sixth step can be reversed. Further, in the above manufacturing method, a method for manufacturing a plurality of optical units 1 together has been described, but the optical units 1 can also be manufactured one by one. In this case, the sixth step is not required.

[0077] As described above, in the optical unit 1, the vibration element 30 provided on the support portion 10 of the base 5 causes the support portion 10 to vibrate, thereby generating torsional vibrations in the first connection portion 13 and the second connection portion 14 of the base 5, and causing the movable portion 15 provided with the optical surface 20s to swing. Thus, by making light incident on the optical surface 20s that swings via the movable portion 15, various optical functions such as optical scanning can be achieved. In particular, in the optical unit 1, at least a part of at least any one of the first region R1 on the support portion 10 on the side of the movable portion 15 with respect to the position where the vibration element 30 is provided, the second region R2 corresponding to the first extension portion 11 and the second extension portion 12, and the third region R3 facing the vibration element 30 in the main surface 5s of the base 5 provided with the optical surface 20s is formed with a dimpled surface.

[0078] The first region R1 and the second region R2 are regions in the main surface 5s that are relatively close to the optical surface 20s (movable portion 15) and where light is likely to be incident. Therefore, when a dimpled surface is formed in the first region R1 and / or the second region R2, the generation of stray light can be suppressed. That is, the optical characteristics are improved. In addition, when a dimpled surface is formed in the third region R3, the adhesion of the vibration element 30 (the layer that contributes to the adhesion of the vibration element 30) to the third region R3 is improved, and the bonding of the vibration element 30 to the main surface 5s is strengthened. By firmly bonding the vibration element 30 to the main surface 5s, torsional vibrations can be reliably generated in the first connection portion 13 and the second connection portion 14 along with the vibration of the vibration element 30 to swing the optical surface 20s (movable portion 15). Thus, the optical characteristics are also improved in this case.

[0079] In addition, in the optical unit 1, the base 5 is made of metal. Therefore, from the viewpoints of maintaining the strength of the base 5 and suppressing rusting of the base 5, it is considered ideal to form the surface of the base 5 into a flat surface. In contrast, as described above, from the viewpoint of improving optical characteristics, the optical unit 1 forms a dimpled surface on the surface of the base 5.

[0080] In addition, in the optical unit 1, the vibration element 30 is provided on the main surface 5s, and a dimpled surface is formed in the first region R1, the second region R2, and the third region R3. Therefore, the optical characteristics are reliably improved. In addition, in the optical unit 1, since a dimpled surface is formed on the entire main surface 5s, the optical characteristics are more reliably improved. In addition, in this case, since the entire main surface 5s can be roughened at the same time when forming the dimpled surface, the manufacturing becomes easy. Moreover, in the optical unit 1, since a dimpled surface is also formed on at least a part of the side surface 5f, the generation of stray light by the side surface 5f is suppressed, and the optical characteristics are more reliably improved.

[0081] In addition, if the order of the second step and the third step is swapped in the above manufacturing method, and the surface of the metal plate 5C including a plurality of substrates 5 is roughened after the metal plate 5C is formed, that is, when the entire surface of the metal plate 5C is roughened as a whole, the entire side surface 5f of the substrate 5 is roughened. In this case, in the optical unit 1, a dimpled surface is formed on the entire side surface 5f. Thus, in this case, the optical characteristics can be more reliably improved.

[0082] Furthermore, based on the same reason, an optical unit 1 with improved optical characteristics can be manufactured according to the above manufacturing method of the optical unit 1.

[0083] The above embodiments have illustrated an example of the present disclosure. Therefore, the present disclosure is not limited to the above examples and can be variously modified. Next, modified examples will be described.

[0084] [First Modified Example of Optical Unit]

[0085] Figure 8 FIG. is a view showing the optical unit of the first modified example. Figure 8 (a) thereof is a plan view, Figure 8 (b) thereof is a cross-sectional view taken along line VIII-VIII. As Figure 8 shown, the optical unit 2A of the first modified example is different from the optical unit 1 in that it does not include the optical component 20, and is the same as the optical unit 1 in other aspects.

[0086] In the optical unit 2A, the optical surface 20s is directly provided on the main surface 5s of the movable part 15s. For example, by mirror-polishing the main surface 5s at the movable part 15s, the optical surface 20s is directly formed as a reflecting mirror surface (reflecting surface) on the main surface 5s. In other words, in the optical unit 2A, the region of the main surface 5s corresponding to the movable part 15s is the optical surface 20s. As an example, the optical unit 2A can be manufactured as follows.

[0087] Figures 9 to 11 FIG. is a perspective view showing Figure 8 one step of the manufacturing method of the optical unit shown. In the manufacturing method of the optical unit 2A, first, as Figure 9 (a) of FIG. shows, a metal plate (metal component) 6A (first step) is prepared. The metal plate 6A has a main surface 6As, a back surface 6Ar on the opposite side of the main surface 6As, and side surfaces 6Af connecting the main surface 6As and the back surface 6Ar to each other. Among the surfaces of the metal plate 6A, at least the main surface 6As has been mirror-polished. That is, in the first step, a metal plate 6A in which at least the main surface 6As has been mirror-polished is prepared.

[0088] Next, as Figure 9As shown in (b) thereof, after forming a mask 61 on the main surface 6As, the surface of the metal plate 6A is roughened to form a metal plate 6B (second step) having a roughened main surface 6Bs, a back surface 6Br, and side surfaces 6Bf. Here, a mask 61 is provided in the region that will later become the movable portion 15. As a result, in the metal plate 6B, a mirror surface remains in the region where the mask 61 is provided, forming the optical surface 20s.

[0089] Next, as Figure 10 shown in (b) thereof, a part of the metal plate 6B is removed (cut out) to form a metal plate 6C (third step) including a plurality (three in this case) of units 2B each composed of a base 5 and an optical surface 20s. The base 5 includes a roughened (i.e., having a dimpled surface) main surface 5s, a back surface 5r, and a partially roughened side surface 5f. The region of the side surface 5f that was originally the side surface 6Bf of the metal plate 6B is roughened, and the newly formed region in this third step is not roughened.

[0090] In addition, the order of the second step and the third step can be swapped. In this case, after removing a part of the metal plate 6A to form a metal plate 6C including a plurality of bases 5, a mask 61 is provided on the metal plate 6C for surface roughening. In the subsequent steps, as Figure 11 shown in (a) thereof, a vibration element 30 (and an upper electrode 31 and a lower electrode 32) is formed on the support portion 10 of each base 5 (fourth step). As a result, a plate member 6D including a plurality of optical units 2A is formed.

[0091] After that, as Figure 11 shown in (b) thereof, by cutting off each optical unit 2A (sixth step), a singulated optical unit 2A is obtained. In the above manufacturing method, a method for manufacturing a plurality of optical units 2A together has been described, but the optical units 2A can also be manufactured one by one. In this case, the sixth step is not required.

[0092] Similar to the optical unit 1, the above optical unit 2A suppresses stray light and strengthens the bonding of the vibration element 30 by forming a dimpled surface, thereby achieving an improvement in optical characteristics. In addition, in the optical unit 2A, since the optical surface 20s is directly formed on the main surface 5s of the movable portion 15s, there is no need to prepare an optical component 20 formed separately from the base 5, achieving cost reduction. Moreover, according to the optical unit 2A, warping of the optical surface 20s is suppressed compared to the case of using the optical component 20.

[0093] [Second Modified Example of Optical Unit]

[0094] Figure 12 is a plan view showing the optical unit of the second modified example. As Figure 12As shown, the optical unit 2C of the second modification is different from the optical unit 1 in that it has a stress relief portion 16, and is the same as the optical unit 1 in other respects. The stress relief portion 16 is used to relieve the stress caused by the torsion of the first connecting portion 13 and the second connecting portion 14. Therefore, the stress relief portion 16 is located between the optical surface 20s and the first connecting portion 13, and between the optical surface 20s and the second connecting portion 14.

[0095] More specifically, in the optical unit 2C, the movable portion 15 includes a stress relief portion 16 and a setting portion 17 for setting the optical surface 20s. That is, in the second modification, the stress relief portion 16 is formed as a part of the movable portion 15 on the base 5. The stress relief portion 16 includes a first portion 16a connected to the first connecting portion 13 and a second portion 16b connected to the second connecting portion 14. The first portion 16a branches from the first connecting portion 13 in both the positive and negative directions of the X-axis direction and extends toward the second connecting portion 14. The second portion 16b extends from the second connecting portion 14 in both the positive and negative directions of the X-axis direction and extends toward the first connecting portion 13.

[0096] The first portion 16a and the second portion 16b are connected and integrated with each other at an intermediate position between the first extension portion 11 and the second extension portion 12 in the Y-axis direction, and the whole is in a ring shape. Here, the first portion 16a and the second portion 16b are each in an arc shape (semicircular shape), and are integrated with each other to form a circular ring shape. The widths of the first portion 16a and the second portion 16b (dimensions in the direction intersecting the Z-axis direction and the extending direction) are smaller than the widths of the first connecting portion 13 and the second connecting portion 14 and the width of the setting portion 17.

[0097] The setting portion 17 extends in the X-axis direction in a manner of bridging a pair of connecting portions between the first portion 16a and the second portion 16b (here, in a straight line shape). Here, the optical surface 20s is set on the setting portion 17 by mounting the optical component 20 on the setting portion 17. However, the optical surface 20s can also be directly set on the setting portion 17 by mirroring the main surface 5s on the setting portion 17.

[0098] Similar to the optical unit 1, the above-described optical unit 2C can also improve optical characteristics by forming a dimpled surface to suppress stray light and strengthen the bonding of the vibration element 30. In addition, in the optical unit 2C, the stress transmission path caused by the torsion of the first connecting portion 13 is divided into two directions by the first portion 16a that branches in the stress relaxation portion 16, and the stress transmission path caused by the torsion of the second connecting portion 14 is similarly divided by the second portion 16b that branches in two directions. Moreover, since the widths of the first portion 16a and the second portion 16b of the stress relaxation portion 16 are relatively small, the stress relaxation portion 16 is preferentially deformed. As a result, the stress caused by the torsion of the first connecting portion 13 and the second connecting portion 14 is relaxed in the stress relaxation portion 16, suppressing the flexure of the optical surface 20s via the installation portion 17. Thereby, the optical characteristics are further improved.

[0099] Here, in the stress relaxation portion 16 and the installation portion 17 (i.e., the movable portion 15), it is possible to configure the side surface 5f not to form a dimpled surface but to be a flat surface. In the optical unit 2C, by providing the stress relaxation portion 16 in the movable portion 15, the area of the region of the side surface 5f corresponding to the movable portion 15 becomes larger. Therefore, by configuring the region of the side surface 5f corresponding to the movable portion 15 to be a flat surface, the effect of suppressing the strength reduction is relatively large. In addition, in this case, compared with the case where a dimpled surface is formed in the region of the side surface 5f corresponding to the movable portion 15, a structure closer to the design value can be formed, the operation of the movable portion 15 can be stabilized, and further, the optical characteristics can be stabilized.

[0100] In addition, the shapes of the stress relaxation portion 16 and the installation portion 17 are not limited to the above examples. As an example, as shown in (a) of Figure 13 , the installation portion 17 can be provided so as to extend in the Y-axis direction. In this case, the first portion 16a and the second portion 16b of the stress relaxation portion 16 extend in such a manner that they branch from the first connecting portion 13 and the second connecting portion 14 in the positive and negative directions of the X-axis, respectively, and then reconnect the branched portions to each other, forming a ring shape. Then, the installation portion 17 extends linearly in the Y-axis direction so as to bridge the first portion 16a and the second portion 16b. In this case, the first portion 16a and the second portion 16b are connected via the installation portion 17.

[0101] In addition, as another example, as shown in Figure 13As shown in (b) of [description], a plurality (two in this case) of setting portions 17 are provided. Here, a pair of setting portions 17 extend in the X-axis direction while being spaced apart from each other. In this case, the first portion 16a and the second portion 16b of the stress relaxation portion 16 are composed of portions that extend linearly in the X-axis direction while branching from the first connecting portion 13 and the second connecting portion 14 toward the positive side and the negative side of the X-axis direction, respectively, and portions that extend linearly in the Y-axis direction from the ends of these portions. The first portion 16a and the second portion 16b are connected and integrated with each other at the portions extending in the Y-axis direction, and are integrally annular (rectangular annular in this case) as a whole. Then, the setting portion 17 extends linearly in the X-axis direction so as to be bridged between the first portion 16a and the second portion 16b.

[0102] Moreover, the above example has described the example in which the first portion 16a and the second portion 16b of the stress relaxation portion 16 branch from the first connecting portion 13 and the second connecting portion 14 in two directions, respectively. However, the first portion 16a and the second portion 16b may be configured to branch from the first connecting portion 13 and the second connecting portion 14 in more than three directions. That is, here, the stress relaxation portion 16 is a portion that is integrally provided with the base 5 between the optical surface 20s and the first connecting portion 13 and between the optical surface 20s and the second connecting portion 14 and branches into a plurality of parts.

[0103] [Third Modified Example of Optical Unit]

[0104] Figure 14 is a plan view showing the optical unit of the third modified example. As Figure 14 shown, compared with the optical unit 1, the optical unit 2D of the third modified example is different from the optical unit 1 in terms of having the stress relaxation portion 21 and the shape of the movable portion 15, and is the same as the optical unit 1 in other aspects. The stress relaxation portion 21 is used to relieve the stress caused by the torsion of the first connecting portion 13 and the second connecting portion 14 in the same manner as in the second modified example. Therefore, the stress relaxation portion 21 is located between the optical surface 20s and the first connecting portion 13 and between the optical surface 20s and the second connecting portion 14 in the same manner as in the second modified example.

[0105] However, in the third modified example, the stress relaxation portion 21 is formed integrally with the optical component 20. That is, the stress relaxation portion 21 is provided annularly (circular annular in this case) around the optical component 20 so as to surround the optical component 20 when viewed from the Z-axis direction. More specifically, here, the first connecting portion 13 and the second connecting portion 14 are connected to each other at the central positions of the first extension portion 11 and the second extension portion 12 in the Y-axis direction, and the movable portion 15 extends linearly from the connecting portion of the first extension portion 11 and the second extension portion 12 to both sides in the X-axis direction.

[0106] Moreover, the stress relaxation portion 21 includes a first portion 21a fixed to a portion on one side in the X-axis direction of the movable portion 15 and a second portion 21b fixed to a portion on the other side in the X-axis direction of the movable portion 15. The first portion 21a branches out in two directions, the positive side and the negative side in the Y-axis direction, from a fixing portion 22a fixed to the movable portion 15 and extends along the X-axis direction. The second portion 21b branches out in two directions, the positive side and the negative side in the Y-axis direction, from a fixing portion 22b fixed to the movable portion 15 and extends along the X-axis direction. The first portion 21a and the second portion 21b are connected and integrated with each other at positions overlapping the first connecting portion 13 and the second connecting portion 14, respectively, when viewed from the Z-axis direction, and the whole is in a ring shape.

[0107] Here, the first portion 21a and the second portion 21b are each in an arc shape (semicircular shape), and are integrated with each other to form a ring shape. The widths of the first portion 21a and the second portion 21b (dimensions in the direction crossing the Z-axis direction and the extending direction) are smaller than the widths of the first connecting portion 13 and the second connecting portion 14 and the width of the movable portion 15. The optical component 20 and the stress relaxation portion 21 are connected and integrated with each other by a pair of connecting portions 23 provided at the connecting portion between the first portion 21a and the second portion 21b (formed integrally from the same material as the optical component 20). On the other hand, the optical component 20 and the stress relaxation portion 21 are separated from each other at portions other than the connecting portion 23, and a space is formed therebetween. Further, the optical surface 20s is spaced apart from the movable portion 15 in the Z-axis direction.

[0108] Similar to the optical unit 1, the above optical unit 2D can also improve the optical characteristics by forming a matte surface to suppress stray light and strengthen the bonding of the vibration element 30. In addition, in the optical unit 2D, the stress transmission path caused by the torsion of the first connecting portion 13 and the second connecting portion 14 is divided by the first portion 21a branching out in two directions from the fixing portion 22a fixed to the movable portion 15, and is divided by the second portion 21b branching out in two directions from the fixing portion 22b fixed to the movable portion 15. Moreover, since the widths of the first portion 21a and the second portion 21b of the stress relaxation portion 21 are relatively small, the stress relaxation portion 21 is preferentially deformed. As a result, the stress caused by the torsion of the first connecting portion 13 and the second connecting portion 14 is relaxed in the stress relaxation portion 21, and the deflection of the optical surface 20s is suppressed. Thereby, the optical characteristics are further improved.

[0109] In the above example, an example in which the first part 21a and the second part 21b of the stress relaxation part 21 branch in two directions from the fixing parts 22a and 22b fixed to the movable part 15 respectively has been described. However, the first part 21a and the second part 21b may be configured to branch in more than three directions from the fixing parts 22a and 22b respectively. That is, here, the stress relaxation part 21 is a part that is integrated with the optical component 20 (separate from the base body 5) and branches into a plurality of parts between the optical surface 20s and the first connecting part 13, and between the optical surface 20s and the second connecting part 14.

[0110] [Fourth modification example of optical unit]

[0111] Figure 15 is a plan view showing the optical unit of the fourth modification example. As Figure 15 shown, the optical unit 2E of the fourth modification example is different from the optical unit 1 in that it includes an optical component 60 instead of the optical component 20 and in the shape of the movable part 15, and is the same as the optical unit 1 in other aspects.

[0112] Here, an opening 15p is formed in the movable part 15. Here, the movable part 15 has an annular shape with a circular opening 15p formed therein, but it may also be other shapes. The optical component 60 is mounted on the movable part 15 such that its center coincides with the center of the opening 15p. More specifically, as an example, the optical component 60 is formed in a disk shape and includes an optical surface 60s and an optical surface 60r on the opposite side of the optical surface 60s. The optical component 60 is mounted on the movable part 15 such that the optical surface 60r faces the main surface 5s, that is, such that the optical surface 60s is located on the side opposite to the main surface 5s. Therefore, in the optical unit 2E, a pair of optical surfaces 60s and 60r are provided on the main surface 5s in the movable part 15. The optical component 60 is made of a light-transmitting material.

[0113] As an example, such an optical component 60 can be configured as a beam splitting filter. In this case, by forming an antireflection film on the optical surface 60s as the light incident surface and forming a beam splitting filter on the optical surface 60r as the light exit surface, the optical unit 2E can be configured as a beam splitting element in which the wavelength of the transmitted light varies with the swing angle of the movable part 15.

[0114] By using such a spectroscopic element, a spectroscopic device can be constituted which allows light emitted from a light source and transmitted or reflected by a measurement object to pass through the spectroscopic element (or to be further reflected or spectroscopically analyzed by the spectroscopic element) and be detected by a light detector. Alternatively, by disposing such a spectroscopic element together with a laser medium inside an optical resonator, a wavelength tunable light source can be constituted which outputs light transmitted through the spectroscopic element and amplified by the optical resonator. In addition, a transmission grating (or a reflection grating) can be used instead of the spectroscopic filter. Moreover, the optical unit 2E can be configured as an optical path changer by making the optical component 60 a transmission refractive element.

[0115] The optical unit 2E configured as a transmission type as described above can also, similarly to the optical unit 1, improve optical characteristics by forming a dimpled surface to suppress stray light and strengthen the bonding of the vibration element 30.

[0116] [Fifth Modification Example of Optical Unit]

[0117] Figure 16 is a plan view showing the optical unit of the fifth modification example. Figure 17 is along Figure 16 the VII-VII line sectional view. As Figure 16 , 17 shown, compared with the optical unit 1, the optical unit 2F of the fifth modification example is different from the optical unit 1 in the electrical connection structure of the vibration element 30 and is the same as the optical unit 1 in other aspects.

[0118] That is, in the optical unit 2F, the upper electrode 31 extends from the vibration element 30 on the support portion 10. More specifically, the upper electrode 31 is located on the support portion 10 and the vibration element 30, and includes a first portion 31a in contact with the vibration element 30 and a second portion 31b provided on the support portion 10 so as to extend from the first portion 31a toward the outer edge of the support portion 10. An insulating layer 33 is provided between the second portion 31b and the support portion 10 (main surface 5s).

[0119] The first portion 31a is the portion of the upper electrode 31 that overlaps the vibration element 30 when viewed from the Z-axis direction. The second portion 31b is the portion of the upper electrode 31 that does not overlap the vibration element 30 (the portion extending from the vibration element 30) when viewed from the Z-axis direction. When viewed from the Z-axis direction, the shortest distance between the second portion 31b and the outer edge of the support portion 10 is less than the shortest distance between the first portion 31a and the outer edge of the support portion 10.

[0120] Similar to the optical unit 1, the above-described optical unit 2F can also improve optical characteristics by forming a dimpled surface to suppress stray light and strengthen the bonding of the vibration element 30. Additionally, in the optical unit 2F, by providing wiring such as leads (e.g., the wiring 41 of the optical device 100) in the second portion 31b extending toward the outer edge of the support portion 10, electrical connection between the vibration element 30 and the outside can be achieved. Therefore, compared with the case where wiring such as leads is directly extended from the outside to the vibration element 30, the length of the wiring such as leads is shortened, enabling stable connection. Here, the outside refers to the structure other than the optical unit 2F. In an optical device (e.g., the optical device 100) having the optical unit 2F, it can be, for example, a structure inside the optical device such as a substrate (e.g., the wiring substrate 115 of the optical device 100) on which the optical unit 2F is mounted.

[0121] [Sixth modification example of the optical unit]

[0122] Figure 18 is a plan view showing the optical unit of the sixth modification example. As Figure 18 shown, compared with the optical unit 1, the optical unit 2G of the sixth modification example is different from the optical unit 1 in the electrical connection structure of the vibration element 30 corresponding to the shape of the support portion 10, and is the same as the optical unit 1 in other aspects.

[0123] That is, in the optical unit 2G, an opening 10p is formed in the support portion 10. The opening 10p is a through-hole that penetrates the base body 5 in the support portion 10. The opening 10p is formed in the support portion 10 such that, when viewed from the Z-axis direction, the shortest distance between the inner edge of the opening 10p and the outer edge of the support portion 10 is less than the shortest distance between the vibration element 30 (upper electrode 31) and the outer edge of the support portion 10. The optical unit 2G is mounted on the wiring substrate 115 such that the electrode 40 provided on the wiring substrate 115 is exposed to the main surface 5s side through the opening 10p. Moreover, the wiring 41 is connected to the electrode 40 and the vibration element 30 (upper electrode 31) via the opening 10p.

[0124] Similar to the optical unit 1, the above-described optical unit 2G can also improve optical characteristics by forming a dimpled surface to suppress stray light and strengthen the bonding of the vibration element 30. Additionally, for the optical unit 2G, similar to the optical unit 2F, the length of the wiring such as wires 41 is shortened, enabling stable connection.

[0125] [Seventh modification example of the optical unit]

[0126] Figure 19 is a plan view showing the optical unit of the seventh modification example. As Figure 19As shown, the optical unit 2H of the seventh modification example differs from the optical unit 1 in terms of the formation range of the dimpled surface, and is the same as the optical unit 1 in other aspects. In the optical unit 2H, a dimpled surface is formed in the portion of the base 5 that is exposed from the opening 112r provided on the lid 112 of the container 110. The portion of the base 5 that is exposed from the opening 112r is the portion of the base 5 that includes the movable portion 15 (i.e., the optical surface 20s), and is the portion that is located inside the opening 112r when viewed from the Z-axis direction.

[0127] Here, a dimpled surface is formed as a whole in the fourth region R4 of the main surface 5s of the base 5 that includes the entire region exposed from the opening 112r. On the other hand, a dimpled surface (constituting a flat surface) is not formed in the region R5 other than the fourth region R4 of the main surface 5s of the base 5. As shown in the figure, the fourth region R4 may not reach the straight line L1 passing through the outer edge on the side of the movable portion 15 of the vibration element 30, or may cross the straight line L1 and extend. In addition, it is not limited to the case where a dimpled surface is formed in the entire portion of the base 5 that is exposed from the opening 112r, and it is sufficient if a dimpled surface is formed in at least a part thereof. Figure 19 In the figure, the fourth region R4 is hatched for convenience.

[0128] Similar to the optical unit 1, the above optical unit 2H can suppress stray light by forming a dimpled surface, thereby improving optical characteristics.

[0129] [First Modification Example of Optical Device]

[0130] Figure 20 is a perspective view showing the optical device of the first modification example. As Figure 20 shown, the optical device 100A differs from the optical device 100 in that it includes a container 110A instead of the container 110, and is the same as the optical device 100 in other aspects.

[0131] The container 110A also has a frame portion 116A provided on the lid 112. The frame portion 116A is erected along the inner edge of the opening 112r of the lid 112 on the lid 112. A window member 113 is mounted on the top of the frame portion 116A to seal the opening 112r. The height of the frame portion 116A with respect to the lid 112 decreases (or increases) as it goes from one side to the other side in the Y-axis direction. Therefore, the window member 113 is inclined in the Y-axis direction (the direction orthogonal to the light scanning direction). By inclining the window member 113 in this way, it is possible to suppress stray light emitted to the outside via the window member 113.

[0132] [Second Modification Example of Optical Device]

[0133] Figure 21 is a perspective view showing the optical device of the second modification example. As Figure 21As shown, the optical device 100B is different from the optical device 100 in that it includes a container 110B instead of the container 110, and is the same as the optical device 100 in other aspects.

[0134] The container 110B also has a frame portion 116B provided on the lid 112. The frame portion 116B is erected along the inner edge of the opening 112r of the lid 112 on the lid 112. A window member 113 is mounted on the top of the frame portion 116B to seal the opening 112r. The height of the frame portion 116B with respect to the lid 112 decreases (or increases) as going from one side to the other side in the X-axis direction. Therefore, the window member 113 is inclined in the X-axis direction (the light scanning direction). By inclining the window member 113 in this way, the stray light emitted to the outside via the window member 113 can be suppressed.

[0135] [Third Modified Example of Optical Device]

[0136] Figure 22 It is a perspective view showing the optical device of the third modified example. Figure 22 The container 110 and the wiring board 115 are omitted. As Figure 22 shown, the optical device 100C of the third modified example is different from the optical device 100 in that it further includes a light source 71 and a detector 72, and is the same as the optical device 100 in other aspects.

[0137] The light source 71 outputs light C (for example, laser). The detector 72 is disposed on the optical axis of the light C output from the light source 71 and is used to detect the light C. The detector 72 can be, for example, a single-element PD or APD, SiPM, or their array or sensor or image sensor, position detection sensor. The light source 71 and the detector 72 are configured such that due to the displacement of the base 5 corresponding to the vibration of the vibration element 30, the optical axis of the light C interferes with a part of the base 5. In Figure 22 (a), the optical axis of the light C is set to interfere with the movable part 15 as the movable part 15 swings. On the other hand, in Figure 22 (b), a connecting portion 19 that connects the first extension portion 11 and the second extension portion 12 is provided on the side of the base 5 opposite to the support portion 10 with the movable part 15 interposed therebetween, and the optical axis of the light C is set to interfere with the connecting portion 19 in response to the deformation (displacement) of the connecting portion 19. In addition, the connecting portion 19 has, for example, the same cross-sectional shape (the cross-sectional shape in the X-Z plane) as the first connecting portion 13 and the second connecting portion 14.

[0138] Based on the above optical device 100C, it is possible to detect the amplitude (swing angle) of the swing of the optical surface 20s (movable part 15) based on the output of the light output from the light source 71 and detected by the detector 72 without being blocked by the base 5. In addition, in the illustrated example, an example in which the light source 71 and the detector 72 are provided outside the optical unit 1 is described, but the light source 71 and / or the detector 72 may also be provided on the base 5. For example, by disposing one of the light source 71 and the detector 72 on the first extension portion 11 or the second extension portion 12, the optical axis of the light C can interfere with the movable part 15. In addition, a through hole may be formed at a position on the movable part 15 side of the support portion 10 relative to the vibration element 30, and the light source 71 may be disposed so as to protrude from the through hole toward the main surface 5s side. In addition, the light source 71 and the detector 72 may be arranged such that the optical axis of the light C interferes with any part, not limited to the movable part 15 and the connecting part 19. By forming a matte surface in the region of the main surface 5s of the base 5 that may interfere with the optical axis of the light C, stray light of the light C can be suppressed and the swing angle can be accurately detected.

[0139] In addition, in the above example, the detector 72 is arranged to detect the light C that passes through without being blocked by a part of the base 5. However, the detector 72 may also be arranged to detect the light C reflected by a part of the base 5. More specifically, the detector 72 may be arranged to detect the light C reflected by the side surface 5f of the base 5 or the connecting part 19. In this case, it is also possible to detect the amplitude (swing angle) of the swing of the optical surface 20s (movable part 15) based on the output of the detector 72.

[0140] [Other modification examples]

[0141] The modification examples of the optical unit and the optical device have been described above, but the present disclosure is not limited to the above modification examples and can be further modified. For example, the optical devices 100, 100A, 100B may include any of the optical units 2A, 2C, 2D, 2E, 2F, 2G, 2H instead of the above optical unit 1. Moreover, in the optical units 1, 2A, 2C, 2D, 2E, 2F, 2G, 2H, the structures of the respective parts can be applied to each other.

[0142] For example, for the optical unit 2A in which the optical surface 20s is directly provided on the movable part 15, the stress relaxation portion 16 of the optical unit 2C can be applied. In addition, for the transmissive optical unit 2E, the stress relaxation portion 16 of the optical unit 2C or the stress relaxation portion 21 of the optical unit 2D can be applied. In addition, the stress relaxation portion 16 and the stress relaxation portion 21 can be used in combination. In addition, the electrical connection method of the vibration elements of the optical units 2F, 2G can be applied to other optical units 2A, 2C, 2D, 2E, 2H.

[0143] In addition, in the above example, the vibration element 30 is provided on the main surface 5s of the base body 5. However, the vibration element 30 may also be provided on the back surface 5r of the base body 5, for example, according to the required vibration mode. In each of the above optical units, a matte surface may be formed only in the region of the main surface 5s corresponding to the first connecting portion 13 and the second connecting portion 14.

[0144] Industrial applicability

[0145] An optical unit, an optical device, and a method for manufacturing an optical unit that can improve optical characteristics can be provided.

[0146] Explanation of reference numerals

[0147] 1, 2A, 2C, 2D, 2E, 2F, 2G, 2H... optical units, 5... base body, 5s... main surface, 5r... back surface, 5f... side surface, 10... support portion, 11... first extension portion, 12... second extension portion, 13... first connecting portion, 14... second connecting portion, 15... movable portion, 16, 21... stress relief portions, 20s, 60s, 60r... optical surfaces, 30... vibration element, 31... upper electrode, 31a... first part, 31b... second part, 71... light source, 72... detector, 100, 100A, 100B... optical devices, 110, 110A, 110B... containers, 112r... opening, R1... first region, R2... second region, R3... third region.

Claims

1. An optical unit, comprising: a base body made of metal, having a main surface and a back surface opposite to the main surface; an optical surface provided on the main surface; and a vibration element provided on the main surface or the back surface, wherein the base body includes: a support portion; a first extension portion and a second extension portion extending from the support portion; a movable portion disposed between the first extension portion and the second extension portion; and a first connection portion connecting the first extension portion to the movable portion and a second connection portion connecting the second extension portion to the movable portion, the vibration element is provided on the support portion, and by vibrating the support portion, torsional vibration is generated in the first connection portion and the second connection portion to swing the movable portion, the optical surface is provided on the main surface in the movable portion, at least a part of at least any one of a first region on the support portion on the main surface closer to the movable portion than the position where the vibration element is provided and a second region on the main surface corresponding to the first extension portion and the second extension portion is formed with a dimpled surface at a position separated from the movable portion when viewed from the thickness direction of the base body.

2. The optical unit according to claim 1, wherein, a dimpled surface is formed in the first region and the second region.

3. The optical unit according to claim 1 or 2, wherein, a dimpled surface is formed on the entire main surface.

4. The optical unit according to any one of claims 1 to 3, wherein, the base body has a side surface connecting the main surface and the back surface, a dimpled surface is formed on the main surface, the back surface and the side surface.

5. The optical unit according to any one of claims 1 to 4, wherein, when viewed from the thickness direction of the base body, at least a part of the first region is adjacent to the movable portion with a gap in the extending direction of the first extension portion and the second extension portion.

6. The optical unit according to claim 5, wherein, a dimpled surface is formed on a part of the first region adjacent to the movable portion with a gap when viewed from the thickness direction of the base body.

7. The optical unit according to any one of claims 1 to 6, wherein, when viewed from the thickness direction of the base body, the first extension portion and the second extension portion are in an elongated shape with the extending direction of the first extension portion and the second extension portion as the long side.

8. The optical unit according to any one of claims 1 to 7, wherein, when viewed from the thickness direction of the base body, the widths of the first extension portion and the second extension portion in a direction crossing the extending direction of the first extension portion and the second extension portion are greater than the widths of the first connection portion and the second connection portion in the extending direction.

9. The optical unit according to any one of claims 1 to 8, wherein, the first extension portion and the second extension portion are supported by the support portion only at one end portion in the extending direction of the first extension portion and the second extension portion, and constitute a cantilever beam.

10. The optical unit according to any one of claims 1 to 9, wherein, the area of the first region is larger than the area of the second region.

11. A manufacturing method of an optical unit, comprising: a first step of preparing a metal component; a second step of forming, after the first step, a substrate having a main surface and a back surface opposite to the main surface from the metal component; and a third step of roughening at least a part of the substrate after the second step, wherein the substrate includes: a support portion for disposing a vibration element; a first extension portion and a second extension portion extending from the support portion; a movable portion disposed between the first extension portion and the second extension portion, and an optical surface is to be disposed on the main surface side; and a first connection portion connecting the first extension portion and the movable portion and a second connection portion connecting the second extension portion and the movable portion, in the third step, at least a part of at least any one of a first region on the main surface on the support portion closer to the movable portion than the position where the vibration element is disposed and a second region on the main surface corresponding to the first extension portion and the second extension portion is roughened at a position separated from the movable portion when viewed from the thickness direction of the substrate.

12. The manufacturing method of the optical unit according to claim 11, wherein, in the third step, the first region and the second region are roughened.

13. The manufacturing method of the optical unit according to claim 11 or 12, wherein, in the third step, the entire main surface is roughened.

14. The manufacturing method of the optical unit according to any one of claims 11 to 13, wherein, the substrate has side surfaces connecting the main surface and the back surface, in the third step, the main surface, the back surface and the side surfaces are roughened.

15. The manufacturing method of the optical unit according to any one of claims 11 to 14, wherein, when viewed from the thickness direction of the substrate, at least a part of the first region is adjacent to the movable portion with a gap therebetween in the extending direction of the first extension portion and the second extension portion.

16. The manufacturing method of the optical unit according to claim 15, wherein, in the third step, a part of the first region adjacent to the movable portion with a gap therebetween when viewed from the thickness direction of the substrate is roughened.

17. The manufacturing method of the optical unit according to any one of claims 11 to 16, wherein, when viewed from the thickness direction of the substrate, the first extension portion and the second extension portion are in an elongated shape with the extending direction of the first extension portion and the second extension portion as the long sides.

18. The manufacturing method of the optical unit according to any one of claims 11 to 17, wherein, when viewed from the thickness direction of the substrate, the widths of the first extension portion and the second extension portion in a direction crossing the extending direction of the first extension portion and the second extension portion are greater than the widths of the first connection portion and the second connection portion in the extending direction.

19. The manufacturing method of the optical unit according to any one of claims 11 to 18, wherein, The first extension part and the second extension part are only supported by the support part at one end in the extension direction of the first extension part and the second extension part, forming a cantilever beam.

20. The manufacturing method of the optical unit according to any one of claims 11 to 19, wherein, the area of the first region is larger than the area of the second region.

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