Vibration module and light deflector

Abstract

A vibration module (3) comprises a drive element (1) and a support substrate (2) that supports the drive element (1). The drive element (1) comprises: a movable part (11); a drive part (12) that rotates the movable part (11) about a rotation axis (R0); a fixed part (15) that is fixed to the lower surface of the support substrate (2) by an adhesive; a coupling part (14) that couples the drive part (12) to the fixed part (15); and a first electrode pad that is installed on the upper surface of the fixed part (15) and that is connected to a drive source of the drive part (12) by a wiring pattern. On the lower surface of the support substrate (2), a second electrode pad is disposed at a position facing the first electrode pad. The support substrate (2) is fixed to the fixed part (15) so that the first electrode pad and the second electrode pad are connected and the support substrate (2) is retracted from the coupling part (14) to the fixed part (15) side.

Description

Vibration module and optical deflector

[0001] The present invention relates to a vibration module that rotates a movable part about a rotation axis, and an optical deflector that includes the vibration module.

[0002] In recent years, drive elements that rotate a movable part using MEMS (Micro Electro Mechanical System) technology have been developed. In this type of drive element, a reflective surface is disposed on the movable part, so that light incident on the reflective surface can be scanned at a predetermined deflection angle. This type of drive element is mounted, for example, on image display devices such as head-up displays and head-mounted displays. In addition, this type of drive element can also be used in laser radars that detect objects using laser light.

[0003] Japanese Patent Application Laid-Open No. 2006-101494 (Patent Document 1) describes a driving element that rotates a movable part using a so-called tuning fork vibrator. In this driving element, two tuning fork vibrators are supported in opposite directions on a frame-shaped support, and a mirror part is driven by these two tuning fork vibrators. A piezoelectric actuator is formed on the arm of the tuning fork vibrator, and a connection terminal for supplying a driving voltage to the piezoelectric actuator is formed on the support.

[0004] Patent No. 5045470

[0005] In the drive element having the above configuration, for example, the lower surface of the frame-shaped support is fixed to a support substrate, and the drive element is mounted on the support substrate. Then, the connection terminals of the drive element are connected to the circuit on the support substrate by wire bonding. However, in this case, the arrangement of the wire bonding increases the size of the entire configuration.

[0006] In view of the above, an object of the present invention is to provide a vibration module and an optical deflector that are capable of smoothly rotating a movable part of a drive element while achieving a compact overall configuration.

[0007] A first aspect of the present invention relates to a vibration module. The vibration module according to this aspect includes a drive element and a support substrate that supports the drive element. The drive element includes a movable part, a drive unit that rotates the movable part about a rotation axis, a fixed part that is fixed to the lower surface of the support substrate with an adhesive, a connecting part that connects the drive unit to the fixed part, and a first electrode pad that is installed on the upper surface of the fixed part and connected to a drive source of the drive unit by a wiring pattern. A second electrode pad is disposed on the lower surface of the support substrate in a position facing the first electrode pad. The first electrode pad and the second electrode pad are connected, and the support substrate is fixed to the fixed part so that the support substrate is retracted from the connecting part toward the fixed part.

[0008] According to the vibration module of this aspect, the first electrode pad and the second electrode pad are connected when the drive element and the support substrate are adhesively fixed together, so the support substrate and the drive element can be electrically connected without using a separate wiring method such as wire bonding. This allows the overall configuration of the vibration module to be miniaturized. Furthermore, because the support substrate is retracted from at least the connecting portion toward the fixed portion, the adhesive that bonds the support substrate and the fixed portion is less likely to reach the connecting portion. This prevents the adhesive from interfering with the rotation of the movable portion. Therefore, the movable portion can be smoothly rotated while the vibration module is miniaturized.

[0009] A second aspect of the present invention relates to an optical deflector. The optical deflector according to this aspect includes the vibration module according to the first aspect and a reflective surface disposed on the surface of the movable part on the same side as the surface to which the support substrate is fixed. The support substrate is disposed in an area other than the area facing the reflective surface.

[0010] Since the optical deflector according to this aspect includes the vibration module according to the first aspect, the optical deflector according to this aspect can smoothly rotate the movable part while miniaturizing the optical deflector. Also, the light incident from above the support substrate can be made to enter the reflective surface without being blocked by the support substrate, and can be efficiently reflected above the support substrate without being blocked by the support substrate.

[0011] As described above, according to the present invention, it is possible to provide a vibration module and an optical deflector that are capable of smoothly rotating the movable part of the drive element while achieving a reduction in the size of the entire configuration.

[0012] The effects and significance of the present invention will become more apparent from the following description of the embodiments, however, the embodiments shown below are merely examples of how the present invention can be implemented, and the present invention is not limited to the embodiments described below.

[0013] FIG. 1 is a perspective view showing the configuration of a drive element according to the first embodiment. FIG. 2 is a perspective view of a drive element according to the first embodiment, as viewed from the bottom side. FIG. 3 is a perspective view showing the configuration of a support substrate according to the first embodiment. FIG. 4 is a perspective view showing the assembly of a vibration module according to the first embodiment. FIG. 5 is a plan view showing the configuration of a vibration module (optical deflector) according to the first embodiment. FIG. 6A is a cross-sectional view of the C1-C2 cross section shown in FIG. 5 according to the first embodiment, as viewed in the negative direction of the X-axis. FIG. 6B is a cross-sectional view of the C3-C4 cross section shown in FIG. 5 according to the first embodiment, as viewed in the positive direction of the Y-axis. FIG. 7A is a cross-sectional view of the C1-C2 cross section shown in FIG. 5 according to a first modification of fixing, as viewed in the negative direction of the X-axis. FIG. 7B is a cross-sectional view of the C1-C2 cross section shown in FIG. 5 according to a second modification of fixing, as viewed in the negative direction of the X-axis. FIG. 8 is a perspective view showing an example of mounting a vibration module (optical deflector) according to the first embodiment. FIG. 9 is a cross-sectional view of a vibration module (optical deflector) installed in a housing according to the first embodiment, viewed in the negative direction of the X axis. FIG. 10 is a plan view showing the configuration of a vibration module (optical deflector) according to a first modified example of the first embodiment. FIG. 11 is a plan view showing the configuration of a vibration module (optical deflector) according to a second modified example of the first embodiment. FIG. 12 is a plan view showing the configuration of a vibration module (optical deflector) according to a third modified example of the first embodiment. FIG. 13 is a plan view showing the configuration of a vibration module (optical deflector) according to a fourth modified example of the first embodiment. FIG. 14 is a plan view showing the configuration of a vibration module (optical deflector) according to a fifth modified example of the first embodiment. FIG. 15 is a plan view showing the configuration of a vibration module (optical deflector) according to a sixth modified example of the first embodiment. FIG. 16 is a perspective view showing the configuration of a drive element according to the second embodiment. FIG. 17 is a plan view showing the configuration of a vibration module (optical deflector) according to the second embodiment. FIG. 18 is a plan view showing the configuration of a vibration module (optical deflector) according to a first modified example of the second embodiment. Fig. 19 is a plan view showing the configuration of a vibration module (optical deflector) according to Modification 2 of Embodiment 2. Fig. 20 is a plan view showing the configuration of a vibration module (optical deflector) according to Embodiment 3.

[0014] However, the drawings are for illustrative purposes only and do not limit the scope of the present invention.

[0015] Hereinafter, embodiments of the present invention will be described with reference to the drawings. For convenience, each drawing is labeled with X, Y, and Z axes that are orthogonal to each other. The Y axis direction is parallel to the rotation axis of the drive element, and the Z axis direction is the thickness direction of the drive element.

[0016] First Embodiment FIG. 1 is a perspective view showing the configuration of a driving element 1, and FIG. 2 is a perspective view of the driving element 1 as viewed from the bottom side (Z-axis negative side).

[0017] The driving element 1 includes a movable portion 11, two driving portions 12, two torsion portions 13, two connecting portions 14, and a fixed portion 15. The driving element 1 has a rectangular outline in a plan view. The driving element 1 has a shape that is symmetrical in the Y-axis direction and in the X-axis direction about the center of the movable portion 11.

[0018] The movable portion 11 is supported by the fixed portion 15 via two torsion portions 13 and two connecting portions 14 so as to be rotatable about a rotation axis R0. The rotation axis R0 extends parallel to the length direction (Y axis direction) of the drive element 1 at the midpoint in the width direction (X axis direction) of the drive element 1. A reflective surface 11a is formed on the upper surface (the surface on the positive side of the Z axis) of the movable portion 11. The reflective surface 11a is formed by laminating a highly reflective material (e.g., metals or metal compounds such as gold, silver, copper, or aluminum, or silicon dioxide or titanium dioxide) on the upper surface of the movable portion 11. The reflective surface 11a may be formed of a dielectric multilayer film. Alternatively, the reflective surface 11a may be formed by the upper surface of the movable portion 11. In this case, the reflective surface may be formed by mirror-finishing the upper surface of the movable portion 11.

[0019] The two torsion sections 13 have a beam-like shape extending along the rotation axis R0 and are arranged to sandwich the movable section 11 in the Y-axis direction. One end of the torsion section 13 on the Y-axis positive side is connected to the side surface of the movable section 11 on the Y-axis positive side, and the other end is connected to the connecting section 14 on the Y-axis positive side. One end of the torsion section 13 on the Y-axis negative side is connected to the side surface of the movable section 11 on the Y-axis negative side, and the other end is connected to the connecting section 14 on the Y-axis negative side.

[0020] The two connecting portions 14 have a plate-like shape extending along the rotation axis R0. The connecting portions 14 connect the drive portion 12 and the torsion portion 13 to the fixed portion 15.

[0021] The two driving units 12 each include a piezoelectric element 12b as a driving source and rotate the movable unit 11 about a rotation axis R0. Each of the two driving units 12 is formed by a tuning fork vibrator. That is, the two driving units 12 are formed by arranging the two tuning fork vibrators in opposite directions along the rotation axis R0.

[0022] Each drive unit 12 includes a pair of arm units 12a extending in an L-shape from the connecting unit 14. A piezoelectric element 12b for driving the movable unit 11 is disposed on the upper surface of the portion of each arm unit 12a extending in the Y-axis direction. In addition, a piezoelectric element 12c for detecting the vibration state of the arm unit 12a is disposed near the base of each arm unit 12a.

[0023] The piezoelectric bodies 12b and 12c have a laminated structure in which an upper electrode layer and a lower electrode layer are respectively arranged above and below a piezoelectric thin film of a predetermined thickness. The piezoelectric thin film is made of a piezoelectric material with a high piezoelectric constant, such as lead zirconate titanate (PZT). The material of the piezoelectric thin film is not limited to PZT, and piezoelectric materials with other compositions may also be used. The upper electrode layer and the lower electrode layer are made of a material with low electrical resistance and high heat resistance, such as platinum (Pt) or gold (Au). The piezoelectric bodies 12b and 12c are formed on the upper surface of the arm portion 12a by a method such as sputtering.

[0024] The fixed portion 15 has a rectangular frame shape in a plan view. The outer periphery of the fixed portion 15 forms the outer periphery of the drive element 1. The fixed portion 15 supports the movable portion 11, the drive portion 12, and the torsion portion 13 via two connecting portions 14. The fixed portion 15 is fixed to the support substrate 2 (see FIG. 3 ), as described below.

[0025] The fixed part 15 includes two first parts 15a connected to the connecting part 14 and extending in a direction perpendicular to the rotation axis R0 (X-axis direction) in a plan view, and two second parts 15b extending from the end of the first part 15a in the X-axis direction toward the movable part 11 in a direction parallel to the rotation axis R0 (Y-axis direction). The frame shape of the fixed part 15 is formed by connecting the two first parts 15a and the two second parts 15b.

[0026] Two terminals 16 are arranged on the upper surface of the fixed portion 15. The terminal 16 on the positive side of the Y-axis is connected to the two piezoelectric bodies 12b and two piezoelectric bodies 12c on the positive side of the Y-axis via wiring 16b. The terminal 16 on the negative side of the Y-axis is connected to the two piezoelectric bodies 12b and two piezoelectric bodies 12c on the negative side of the Y-axis via wiring 16b. Similar to the piezoelectric bodies 12b and 12c, the wiring 16b has a layered structure in which upper and lower electrode layers are arranged above and below the piezoelectric thin film. On the upper surface of the terminal 16, four electrode pads 16a are arranged, connected to the upper electrode layers of the corresponding piezoelectric bodies 12a and 12b, and two electrode pads 16a are arranged, connected to the lower electrode layers of the corresponding piezoelectric bodies 12a and 12b, and used to connect these lower electrode layers to ground. Each electrode pad 16a is exposed upward. An insulating protective film is disposed on the upper surface of the area of ​​the terminal portion 16 other than the electrode pad 16a, the upper surface of the wiring 16b, and the upper surfaces of the piezoelectric bodies 12b and 12c.

[0027] The driving element 1 is formed by removing the material layer 1b by etching or the like from an integral structure consisting of a substrate 1a of a predetermined thickness and a material layer 1b so as to leave a region corresponding to the fixed portion 15. This increases the mechanical strength of the fixed portion 15.

[0028] The material of the material layer 1b may be different from that of the base material 1a, or may be the same as that of the base material 1a. The driving element 1 may also be configured by laminating the material layer 1b on the lower surface of a base material 1a having a predetermined thickness. In this case, the material layer 1b is laminated only in the region corresponding to the fixed portion 15.

[0029] The substrate 1a has the same contour as the driving element 1 in a plan view and a constant thickness. A reflecting surface 11a, piezoelectric elements 12b and 12c, terminal portion 16, electrode pads 16a, and wiring 16b are arranged in corresponding regions on the top surface of the substrate 1a. The substrate 1a is also removed by etching or the like so as to leave the movable portion 11, driving portion 12, torsion portion 13, and connecting portion 14, thereby forming the movable portion 11, driving portion 12, torsion portion 13, and connecting portion 14 on the substrate 1a. The area of ​​the substrate 1a other than the movable portion 11, driving portion 12, torsion portion 13, and connecting portion 14 is an opening 15c that penetrates vertically.

[0030] The substrate 1a is integrally formed from, for example, silicon (Si). However, the material constituting the substrate 1a is not limited to silicon (Si) and may be other materials. The material constituting the substrate 1a is preferably a material with high mechanical strength and Young's modulus. The same applies to the material of the material layer 1b.

[0031] When the drive element 1 is driven, an AC voltage is applied to the four piezoelectric bodies 12b to resonantly drive the movable part 11 at the natural frequency (resonance frequency) of the drive element 1. As a result, each of the four piezoelectric bodies 12b deforms due to the inverse piezoelectric effect. At this time, the AC voltage applied to two piezoelectric bodies 12b aligned in the Y-axis direction is set to the same phase, and the AC voltage applied to two piezoelectric bodies 12b aligned in the X-axis direction is set to the opposite phase. As a result, the deformation direction (amplitude direction) of the two piezoelectric bodies 12b on the positive side of the X-axis is opposite to the deformation direction (amplitude direction) of the piezoelectric body 12b on the negative side of the X-axis. In this way, the deformation of the four piezoelectric bodies 12b deforms the arm portion 12a, and the movable part 11 is resonantly driven around the rotation axis R0 at a predetermined resonant frequency via the two torsion portions 13.

[0032] The four piezoelectric elements 12c for vibration detection generate electric currents due to the piezoelectric effect in response to the deformation of the corresponding arms 12a. Therefore, the vibration state of the arms 12a can be monitored from these electric currents. An external drive circuit connected to the support substrate 2 (described later) uses these electric currents to control the AC voltages applied to the piezoelectric elements 12b so that the amplitude, frequency, and phase of each arm 12a converge to their respective target values. This causes the movable element 11 and the reflecting surface 11a to rotate at the target resonant frequency and deflection angle.

[0033] Fig. 3 is a perspective view showing the configuration of the support substrate 2. Fig. 3 is a perspective view of the support substrate 2 as viewed from the bottom surface side (negative side of the Z axis).

[0034] The support substrate 2 has a frame shape with a rectangular outline in a plan view. The support substrate 2 includes two first portions 2a that are overlapped with first portions 15a (see FIG. 1) of the fixing portion 15, and two second portions 2b that are connected to the first portions 2a and overlap with second portions 15b (see FIG. 1) of the fixing portion 15. The frame shape of the support substrate 2 is formed by connecting the two first portions 2a and the two second portions 2b. The support substrate 2 has an opening 2c that is surrounded by the first portions 2a and the second portions 2b and penetrates the support substrate 2 in the Z-axis direction. The opening 2c has a rectangular shape in a plan view. Four screw holes 2d that penetrate the support substrate 2 in the Z-axis direction are formed in the corners of the support substrate 2.

[0035] The support substrate 2 is made of a material with a high modulus of elasticity, such as a glass epoxy substrate, a paper phenol substrate, a ceramic substrate, or a glass substrate.

[0036] Two terminals 21 are arranged on the lower surface (negative surface of the Z-axis) of the support substrate 2. Six electrode pads 21a are arranged on each terminal 21, exposed downward (in the negative direction of the Z-axis). The electrode pads 21a are made of a metal with high electrical conductivity, such as copper (Cu) or gold (Au). Each electrode pad 21a in the two terminals 21 is connected to a connection terminal 22 installed on the side of the support substrate 2 via a wiring pattern (not shown) arranged on the surface of the support substrate 2. In this case, the wiring pattern is also made of a metal with high electrical conductivity, such as copper (Cu) or gold (Au). An insulating protective film is arranged on the lower surface (negative surface of the Z-axis) of the area other than the electrode pads 21a in the terminal 21 and on the lower surface (negative surface of the Z-axis) of the wiring pattern connecting each electrode pad 21a to the connection terminal 22. For convenience, FIG. 3 shows a state in which a flexible printed circuit board (FPC) is connected to the connection terminal 22.

[0037] The six electrode pads 21a in the terminal portion 21 on the Y-axis positive side provided on the support substrate 2 are arranged at positions that overlap with the six electrode pads 16a (see FIG. 1) in the terminal portion 16 on the Y-axis positive side provided on the drive element 1 when the support substrate 2 and the drive element 1 are fixed together. Similarly, the six electrode pads 21a in the terminal portion 21 on the Y-axis negative side provided on the support substrate 2 are arranged at positions that overlap with the six electrode pads 16a (see FIG. 1) in the terminal portion 16 on the Y-axis negative side provided on the drive element 1 when the support substrate 2 and the drive element 1 are fixed together.

[0038] The electrode pads 21a and 16a arranged at positions where they overlap each other are equal in size, and the centers of the electrode pads 21a and 16a arranged at positions where they overlap each other are aligned. However, the electrode pads 21a and 16a arranged at positions where they overlap each other may be different in size, and the centers of the electrode pads 21a and 16a arranged at positions where they overlap each other may not be aligned.

[0039] FIG. 4 is a perspective view showing the assembly of the vibration module 3. As shown in FIG.

[0040] The upper surface (the surface on the positive side of the Z axis) of the fixing portion 15 of the driving element 1 is fixed to the lower surface (the surface on the negative side of the Z axis) of the support substrate 2 with an adhesive 24, which will be described later. At this time, the fixing portion 15 is fixed to the lower surface of the support substrate 2 so that the center of the driving element 1 and the center of the support substrate 2 coincide with each other in a plan view. The fixing of the driving element 1 and the support substrate 2 will be described later with reference to Figures 6(a) and (b). When the support substrate 2 supports the driving element 1, a vibration module 3 consisting of the driving element 1 and the support substrate 2 is completed.

[0041] By fixing the driving element 1 to the support substrate 2, each electrode pad 21a provided on the support substrate 2 is electrically connected to a corresponding electrode pad 16a provided on the driving element 1. In this way, the electrode pad 16a of the driving element 1 is connected to a connection terminal 22 (see FIG. 3) via the electrode pad 21a on the support substrate 2, and is connected to an external driving circuit via a flexible substrate FPC (see FIG. 3) connected to the connection terminal 22.

[0042] In this embodiment, a reflecting surface 11a is formed on the upper surface of the movable part 11. Therefore, the vibration module 3 constitutes an optical deflector 3a that deflects light incident on the reflecting surface 11a in response to the driving of the movable part 11.

[0043] FIG. 5 is a plan view showing the configuration of the vibration module 3 (optical deflector 3a).

[0044] 5, the portion of the drive element 1 that is hidden by the support substrate 2 when viewed in the negative direction of the Z axis is shown by a dashed line for convenience. In a plan view, the outline of the support substrate 2 is located outside the outline of the drive element 1, and the four screw holes 2d are located outside the outline of the drive element 1.

[0045] For convenience, a boundary line B1 between the connecting portion 14 and the fixed portion 15 (first portion 15a) of the driving element 1 is shown by a dotted line. As shown in Fig. 1, the upper surface of the substrate 1a is flat at the boundary line B1, but as shown in Fig. 2, the material layer 1b is formed outward from the boundary line B1.

[0046] In a plan view, the side of the outline of the opening 2c in the support substrate 2 extending in the X-axis direction is receded outside the boundary line B1 (in the direction away from the movable part 11). The side of the outline of the opening 2c in the support substrate 2 extending in the Y-axis direction is inward of the side of the opening 15c in the drive element 1 extending in the Y-axis direction (in the direction approaching the movable part 11). The reflecting surface 11a formed on the movable part 11 is open upward (in the positive direction of the Z-axis) through the opening 2c in the support substrate 2.

[0047] FIG. 6A is a cross-sectional view of the C1-C2 cross section shown in FIG. 5 as viewed in the negative direction of the X axis.

[0048] The support substrate 2 has an edge E11 parallel to the X-Z plane on the inside of the first portion 2a (on the movable portion 11 side, on the positive side of the Y axis in FIG. 6A). The fixed portion 15 has an edge E21 parallel to the X-Z plane on the inside of the first portion 15a. The edge E11 of the support substrate 2 is retracted by a distance D1 outward from the edge E21 of the fixed portion 15 (on the fixed portion 15 side, on the negative side of the Y axis in FIG. 6A).

[0049] FIG. 6B is a cross-sectional view of the C3-C4 cross section shown in FIG. 5 as viewed in the positive direction of the Y axis.

[0050] The support substrate 2 has an edge E12 parallel to the YZ plane on the inside of the second portion 2b (on the movable portion 11 side, on the positive side of the X axis in FIG. 6B). The fixed portion 15 has an edge E22 parallel to the YZ plane on the inside of the second portion 15b. The edge E12 of the support substrate 2 is recessed inward by a distance D2 from the edge E22 of the fixed portion 15.

[0051] When the fixing portion 15 is fixed to the support substrate 2, as shown in Fig. 6(a), solder 23 is applied to the electrode pad 21a or the electrode pad 16a, and the upper surface of the fixing portion 15 is placed on the lower surface of the support substrate 2. This electrically connects the two corresponding electrode pads 21a, 16a. Thereafter, as shown in Figs. 6(a) and 6(b), adhesive 24 is injected from the gap between the support substrate 2 and the fixing portion 15 into the entire area where the support substrate 2 and the fixing portion 15 face each other.

[0052] The adhesive 24 is, for example, an underfill material, and may be, for example, an epoxy resin, a silicone resin, an acrylic resin, or a urethane resin.

[0053] As shown in FIG. 6A , the adhesive 24 between the first portion 2 a and the first portion 15 a is disposed so as to extend inward beyond the edge E11 of the support substrate 2 and to be located outside the edge E21 of the fixing portion 15. The adhesive 24 on the inside of the edge E11 is disposed so as to form a fillet, i.e., so as to cover and wet the edge E11. The width of the fillet extending inward from the edge E11 can be adjusted to approximately 0 mm or more and 1 mm or less by, for example, surface modification of the edge E11 by UV or plasma irradiation or the like, and surface modification of the fixing portion 15 by UV or plasma irradiation or the like. Similarly, a fillet of the adhesive 24 is also formed on the outside of the first portion 15 a of the fixing portion 15.

[0054] 6B, the adhesive 24 between the second portion 2b and the second portion 15b is disposed so as to extend inward beyond the edge E22 of the fixing portion 15 and to be positioned outside the edge E12 of the support substrate 2. The adhesive 24 on the inside of the edge E22 is disposed so as to form a fillet, i.e., so as to cover and wet the edge E22. The width of the fillet extending inward from the edge E22 can be adjusted to approximately 0 mm or more and 1 mm or less, for example, by surface modification of the edge E22, such as by irradiating it with UV or plasma. Similarly, a fillet of the adhesive 24 is also formed on the outside of the second portion 15b of the fixing portion 15.

[0055] 6( a), if the distance D1 is short, the adhesive 24 will reach the connecting portion 14, hindering the rotation of the movable portion 11. To avoid this rotational hindrance, it is preferable that the distance D1 be longer. On the other hand, the longer the distance D1, the smaller the adhesion area between the first portion 2a of the support substrate 2 and the first portion 15a of the fixed portion 15, and therefore the weaker the bond between the support substrate 2 and the fixed portion 15. Therefore, it is necessary to appropriately select the distance D1.

[0056] More specifically, when the distance D1 is 0.5 mm or more, a fillet is formed on the edge E11 while preventing the fillet from overlapping the connecting portion 14. On the other hand, when the distance D1 is 1 mm or less, a fillet is formed on the edge E11 while increasing the bonding area of ​​the first portions 2a, 15a. For the above reasons, the distance D1 is preferably greater than 0 mm and equal to or less than 3 mm, more preferably equal to or greater than 0.5 mm and equal to or less than 2 mm, and even more preferably equal to or greater than 0.5 mm and equal to or less than 1 mm.

[0057] Furthermore, increasing the distance D2 shown in FIG. 6B makes it easier to form a fillet at the edge E22, and the wetting and spreading effect of the fillet increases the bonding area, thereby strengthening the bond between the support substrate 2 and the fixing portion 15. Furthermore, stronger bonding increases the robustness of the entire module, and the width of the second portion 15b of the fixing portion 15 in the X-axis direction can be reduced, thereby also reducing the width of the support substrate 2 in the X-axis direction. This allows the vibration module 3 to be miniaturized in the X-axis direction. Furthermore, setting the distance D2 to 0 mm or more makes it easier to form a fillet at the edge E22, thereby strengthening the bond between the support substrate 2 and the fixing portion 15. On the other hand, decreasing the distance D2 increases the bonding area between the second portion 2b of the support substrate 2 and the second portion 15b of the fixing portion 15, thereby strengthening the bond between the support substrate 2 and the fixing portion 15.

[0058] More specifically, when the distance D2 is 1 mm or less, a fillet can be formed at the edge E22 while the bonding area of ​​the second portions 2 b, 15 b can be increased. For these reasons, the distance D2 is preferably greater than 0 mm and less than or equal to 3 mm, more preferably greater than 0 mm and less than or equal to 2 mm, and even more preferably greater than 0 mm and less than or equal to 1 mm.

[0059] The connection of the electrode pads 21a, 16a and the fixing of the support substrate 2 and the fixing portion 15 are not limited to being performed using solder 23 and adhesive 24, but may also be performed using adhesive 25 as shown in Figure 7(a) or adhesive 26 as shown in Figure 7(b).

[0060] In the example shown in FIG. 7( a), the adhesive 25 includes an adhesive material and a conductive filler dispersed in the adhesive material. The adhesive material of the adhesive 25 can be the same material as the adhesive 24, and the conductive filler of the adhesive 25 can be a conductive metal material. The adhesive 25 is, for example, an anisotropic conductive paste (ACP). In this case, the adhesive 25 is also disposed over the entire area where the support substrate 2 and the fixing portion 15 face each other, and a fillet is formed at the end of the adhesive 25. The conductive filler contained in the adhesive 25 electrically connects electrode pads arranged opposite each other in the Z-axis direction while electrically disconnecting adjacent electrode pads arranged parallel to the X-Y plane.

[0061] In the example shown in FIG. 7B , the adhesive 26 includes an adhesive material and a conductive filler dispersed in the adhesive material. The adhesive material of the adhesive 26 can be an adhesive containing the same material as the adhesive 24, and the conductive filler of the adhesive 26 can be a conductive metal material. The adhesive 26 is, for example, an anisotropic conductive film (ACF). In this case, too, the adhesive 26 is disposed over the entire area where the support substrate 2 and the fixing portion 15 face each other, and a fillet is formed at the end of the adhesive 26. The conductive filler contained in the adhesive 26 electrically connects the electrode pads disposed opposite each other in the Z-axis direction.

[0062] In order to facilitate the formation of fillets, adhesives 24, 25, and 26 are each arranged so that the thickness of adhesives 24, 25, and 26 after hardening is, for example, 10 μm or more and 200 μm or less, preferably 30 μm or more and 150 μm or less, and more preferably 50 μm or more and 100 μm or less.

[0063] FIG. 8 is a perspective view showing an example of mounting the vibration module 3 (optical deflector 3a).

[0064] The vibration module 3 (optical deflector 3a) is used in head-mounted displays (AR glasses, AR goggles, VR glasses, VR goggles, etc.), in-vehicle head-up displays, etc. The vibration module 3 (optical deflector 3a) is mounted on a target device by being fixed to a housing 4, for example, as shown in FIG. 8 . Assembly in this case will be described below.

[0065] The housing 4 is a plate-like member with a rectangular outline in a plan view. Four holes 41 are formed in the housing 4, which respectively face the four screw holes 2d of the support substrate 2 when the support substrate 2 and the housing 4 are stacked together. The upper ends of four bolts 42 are fixed to the four screw holes 2d of the fixing portion 15, and the lower ends of the four bolts 42 are fixed to the four holes 41 of the housing 4 by nuts 43. In this way, the vibration module 3 (optical deflector 3a) is installed in the housing 4 with a predetermined gap between it and the top surface of the housing 4.

[0066] FIG. 9 is a cross-sectional view of the vibration module 3 (optical deflector 3a) installed in the housing 4 cut along the YZ plane passing through the rotation axis R0, viewed in the negative direction of the X axis.

[0067] Incident light incident on the vibration module 3 (optical deflector 3a) from above (positive side of the Z axis) is irradiated onto the reflective surface 11a of the movable part 11 through the opening 2c of the support substrate 2. The incident light is reflected by the reflective surface 11a in a direction according to the rotation angle of the movable part 11. The incident light reflected by the reflective surface 11a is irradiated as reflected light onto a scanning region located above the vibration module 3 (optical deflector 3a) through the opening 2c.

[0068] <Effects of First Embodiment> According to the first embodiment, the following effects are achieved.

[0069] As shown in Fig. 4, the vibration module 3 includes a driving element 1 and a support substrate 2 that supports the driving element 1. As shown in Fig. 1, the driving element 1 includes a movable portion 11, a driving portion 12 that rotates the movable portion 11 about a rotation axis R0, a fixed portion 15 that is fixed to the lower surface of the support substrate 2 with adhesive 24 (see Figs. 6(a) and 6(b)), a connecting portion 14 that connects the driving portion 12 to the fixed portion 15, and an electrode pad 16a (first electrode pad) that is installed on the upper surface of the fixed portion 15 and connected to the piezoelectric element 12b (driving source) of the driving portion 12 by wiring 16b (wiring pattern). As shown in Fig. 4, an electrode pad 21a (second electrode pad) is arranged on the lower surface of the support substrate 2 in a position facing the electrode pad 16a (first electrode pad). As shown in FIG. 6( a), the electrode pad 16 a (first electrode pad) and the electrode pad 21 a (second electrode pad) are connected, and as shown in FIG. 5, the support substrate 2 is fixed to the fixing portion 15 so that the support substrate 2 retreats from the connecting portion 14 toward the fixing portion 15.

[0070] According to this configuration, the electrode pads 16a, 21a are connected when the drive element 1 and the support substrate 2 are adhesively fixed, so the support substrate 2 and the drive element 1 can be electrically connected without using a separate wiring means such as wire bonding. This allows the overall configuration of the vibration module 3 to be miniaturized. Furthermore, because the support substrate 2 is retracted at least from the connecting portion 14 toward the fixed portion 15, the adhesive 24 that bonds the support substrate 2 and the fixed portion 15 is less likely to reach the connecting portion 14. This prevents the adhesive 24 from interfering with the rotation of the movable portion 11. Therefore, the movable portion 11 can be smoothly rotated while the vibration module 3 is miniaturized.

[0071] 5, the fixed portion 15 includes a first portion 15a connected to the connecting portion 14 and extending in a direction perpendicular to the rotation axis R0 (X-axis direction) in a plan view, and a second portion 15b extending from an end of the first portion 15a toward the movable portion 11 in parallel to the rotation axis R0 (Y-axis direction). As shown in Figures 6(a) and 6(b), the support substrate 2 has an edge E11 (first edge) and an edge E12 (second edge) that extend along an inner edge E21 (first edge) of the first portion 15a of the fixed portion 15 and an inner edge E22 (second edge) of the second portion 15b of the fixed portion 15, respectively, in a plan view. The edge E11 (first edge) of the support substrate 2 is retracted toward the fixed portion 15 from the edge E21 (first edge) of the fixed portion 15, and the edge E12 (second edge) of the support substrate 2 is recessed toward the rotation axis R0 from the edge E22 (second edge) of the fixed portion 15.

[0072] With this configuration, the upper surfaces of the first portion 15a and the second portion 15b of the fixed portion 15 can be used to bond and fix the driving element 1 to the support substrate 2, thereby firmly fixing the driving element 1 to the support substrate 2. Furthermore, because the edge E11 of the support substrate 2 is recessed toward the fixed portion 15 from the edge E21 of the fixed portion 15, the adhesive 24 used to bond and fix the support substrate 2 to the first portion 15a is less likely to reach the connecting portion 14. This allows the movable portion 11 to rotate smoothly. Furthermore, because the edge E12 of the support substrate 2 is recessed toward the rotation axis R0 from the edge E22 of the fixed portion 15, the adhesive 24 used to bond and fix the support substrate 2 to the second portion 15b spreads further along the support substrate 2. This further strengthens the bond between the support substrate 2 and the second portion 15b.

[0073] As shown in FIG. 6A, in plan view, a distance D1 between an edge E11 (first edge) of the support substrate 2 and an edge E21 (first edge) of the fixing portion 15 is greater than 0 mm and equal to or less than 3 mm.

[0074] According to this configuration, by retracting the edge E11 of the support substrate 2 outward from the edge E21 of the fixed portion 15 by more than 0 mm, the adhesive 24 is less likely to reach the connecting portion 14, allowing for smooth rotation of the movable portion 11. Furthermore, by setting the distance D1 by which the edge E11 of the support substrate 2 is retracted outward from the edge E21 of the fixed portion 15 to 3 mm or less, the adhesive area between the support substrate 2 and the first portion 15a of the fixed portion 15 can be increased, thereby enabling the support substrate 2 and the first portion 15a to be firmly fixed together.

[0075] As shown in FIG. 6B, in plan view, the distance D2 between the edge E12 (second edge) of the support substrate 2 and the edge E22 (second edge) of the fixing portion 15 is greater than 0 mm and equal to or less than 3 mm.

[0076] According to this configuration, by retracting the edge E22 of the fixing portion 15 outward from the edge E12 of the support substrate 2 by more than 0 mm, a fillet is easily formed at the edge E22. The wetting and spreading effect of the fillet increases the bonding area, thereby strengthening the bond between the support substrate 2 and the fixing portion 15. Furthermore, the stronger bond increases the robustness of the entire module, and the width of the second portion 15b of the fixing portion 15 can be reduced, allowing the driver element 1 and the vibration module 3 to be miniaturized in the direction perpendicular to the rotation axis R0 (the X-axis direction). Furthermore, by setting the distance D2 by which the edge E12 of the support substrate 2 inward from the edge E22 of the fixing portion 15 to 3 mm or less, the bonding area between the support substrate 2 and the second portion 15b of the fixing portion 15 can be increased, thereby strengthening the bond between the support substrate 2 and the second portion 15b.

[0077] 5, the driving element 1 includes, in a plan view, a set of a driving unit 12, a connecting unit 14, and a first portion 15a, which are arranged along the rotation axis R0 on both sides of the movable unit 11. Two second portions 15b connect both ends of the two first portions 15a, respectively.

[0078] According to this configuration, both ends of the first portion 15a are connected to the second portion 15b, thereby strengthening the fixing portion 15. Furthermore, by adhesively fixing at least one of the two second portions 15b to the support substrate 2, the driving element 1 can be supported by the support substrate 2 with higher rigidity.

[0079] As shown in Figure 5, the support substrate 2 has two first portions 2a that are overlaid on the two first portions 15a of the fixed portion 15, and two second portions 2b that are overlaid on the two second portions 15b of the fixed portion 15.

[0080] According to this configuration, the upper surfaces of the first part 15a and the second part 15b of the fixing portion 15 can be used for adhesively fixing to the first part 2a and the second part 2b of the support substrate 2, respectively, so that the driving element 1 can be firmly fixed to the support substrate 2.

[0081] As shown in Figure 5, the two first portions 2a of the support substrate 2 are arranged corresponding to the two first portions 15a of the fixing portion 15, respectively, and the two second portions 2b of the support substrate 2 connect both ends of the two first portions 2a of the support substrate 2, respectively.

[0082] According to this configuration, both ends of the two first portions 2a of the support substrate 2 are connected to the two second portions 2b of the support substrate 2, thereby making the support substrate 2 stronger. Furthermore, by adhesively fixing at least one of the two second portions 15b of the fixing portion 15 to the second portion 2b of the support substrate 2, the drive element 1 can be supported on the support substrate 2 with higher rigidity.

[0083] As shown in Figure 6 (a), the electrode pad 16a (first electrode pad) of the fixing portion 15 and the electrode pad 21a (second electrode pad) of the support substrate 2 are electrically connected by solder 23, and the adhesive 24 is made of a resin material.

[0084] This configuration allows the electrode pad 16a and the electrode pad 21a to be firmly connected to each other.

[0085] In the modification of FIG. 7( a ), the adhesive 25 is made of a conductive filler and a resin material, and in the modification of FIG. 7( b ), the adhesive 26 is made of a conductive filler and a resin material.

[0086] This configuration makes it easier to arbitrarily set the bonding location between the support substrate 2 and the fixing portion 15. That is, in the modified example of Figures 7(a) and (b), it is only necessary to apply adhesive 25 or place adhesive 26 in the region including electrode pad 16a of the fixing portion 15 or the region including electrode pad 21a of the support substrate 2, and then overlap and fix the fixing portion 15 to the support substrate 2. This makes it easier to arbitrarily set the bonding location between the support substrate 2 and the fixing portion 15, in other words, the positions at which the adhesives 25 and 26 are disposed, compared to the fixing method shown in Figures 6(a) and (b).

[0087] 6(a) and 6(b), at least a part of the adhesive 24 is disposed so as to protrude from the support substrate 2 in plan view. Similarly, in the modified examples of FIGS. 7(a) and 7(b), at least a part of the adhesives 25 and 26 is disposed so as to protrude from the support substrate 2 in plan view.

[0088] According to this configuration, the adhesives 24, 25, and 26 protrude from the support substrate 2 to form fillets, thereby increasing the contact area between the adhesives 24, 25, and 26 and the support substrate 2 and the fixed portion 15, thereby enabling the support substrate 2 and the fixed portion 15 to be firmly fixed in that area.

[0089] 5, the optical deflector 3a includes a vibration module 3 and a reflecting surface 11a disposed on the surface of the movable part 11 on the same side (positive side of the Z axis) as the surface to which the support substrate 2 is fixed. The support substrate 2 is disposed in an area other than the area facing the reflecting surface 11a.

[0090] Since the optical deflector 3a includes the vibration module 3, this configuration allows the optical deflector 3a to be miniaturized while smoothly rotating the movable part 11. In addition, as shown in Figure 9, light incident from above the support substrate 2 is made to enter the reflective surface 11a without being blocked by the support substrate 2, and can be efficiently reflected upward from the support substrate 2 without being blocked by the support substrate 2.

[0091] <First Modification of First Embodiment> The fixed portion 15 of the first embodiment includes a pair of second portions 15b sandwiching the movable portion 11 therebetween, but one of the two second portions 15b may be omitted from the configuration of the first embodiment. For example, as shown in Fig. 10 , the second portion 15b on the positive side of the X-axis may be omitted.

[0092] FIG. 10 is a plan view showing the configuration of the vibration module 3 (optical deflector 3a) according to the first modification of the first embodiment.

[0093] In a plan view, the driving element 1 includes a set of a driving unit 12, a connecting unit 14, and a first portion 15a on both sides of the movable portion 11 along the rotation axis R0. One second portion 15b connects one end (end on the negative side of the X axis) of the two first portions 15a.

[0094] Even in this configuration, the movable part 11 is supported and driven on both sides, allowing the movable part 11 to be driven stably and efficiently. Furthermore, since one second part 15b connects one end of each of the two first parts 15a, the two first parts 15a can be integrated, strengthening the fixed part 15. Furthermore, by adhesively fixing the second part 15b to the support substrate 2, the drive element 1 can be supported on the support substrate 2 with high rigidity.

[0095] <Modification 2 of Embodiment 1> The support substrate 2 of Embodiment 1 includes a pair of second portions 2 b sandwiching the movable portion 11, but one of the two second portions 2 b may be omitted from the configuration of Embodiment 1. For example, as shown in FIG. 11 , the second portion 2 b on the positive side of the X-axis may be omitted.

[0096] FIG. 11 is a plan view showing the configuration of the vibration module 3 (optical deflector 3a) according to the second modification of the first embodiment.

[0097] The support substrate 2 has two first portions 2a that are respectively overlapped on the two first portions 15a of the fixed portion 15, and one second portion 2b that is connected to the two first portions 2a of the support substrate 2 and overlapped on the second portion 15b of the fixed portion 15.

[0098] Even in this configuration, the upper surfaces of the first portion 15a and the second portion 15b of the fixing portion 15 can be used to adhesively fix the first portion 2a and the second portion 2b of the support substrate 2, respectively, and therefore the drive element 1 can be firmly fixed to the support substrate 2. Furthermore, in this modified example, compared to the first embodiment, the second portion 2b on the positive side of the X axis is omitted, and therefore the support substrate 2 and the vibration module 3 (optical deflector 3a) can be made smaller in the X axis direction.

[0099] <Modification 3 of Embodiment 1> The support substrate 2 of Embodiment 1 includes a pair of first portions 2 a sandwiching the movable portion 11, but one of the two first portions 2 a may be omitted from the configuration of Embodiment 1. For example, as shown in FIG. 12 , the first portion 2 a on the negative side of the Y axis may be omitted.

[0100] FIG. 12 is a plan view showing the configuration of the vibration module 3 (optical deflector 3a) according to the third modification of the first embodiment.

[0101] The support substrate 2 includes one first portion 2a that overlaps with the first portion 15a on the Y-axis positive side of the fixed portion 15, and two second portions 2b that are connected to the one first portion 2a of the support substrate 2 and overlap with the second portion 15b of the fixed portion 15. In this case, since the support substrate 2 does not overlap with the first portion 15a on the Y-axis negative side of the fixed portion 15, the terminal portions 16 and 21 on the Y-axis negative side are installed on the second portions 15b and 2b on the X-axis negative side, respectively, in comparison with the first embodiment.

[0102] Even in this configuration, the upper surfaces of the first portion 15a and the second portion 15b of the fixing portion 15 can be used to adhesively fix the first portion 2a and the second portion 2b of the support substrate 2, respectively, and therefore the drive element 1 can be firmly fixed to the support substrate 2. Furthermore, in this modified example, compared to the first embodiment, the first portion 2a on the negative side of the Y axis is omitted, and therefore the support substrate 2 and the vibration module 3 (optical deflector 3a) can be made smaller in the Y axis direction.

[0103] <Fourth Modification of First Embodiment> In the first embodiment, the terminal portions 21 and 16 are respectively provided on the first portions 2 a and 15 a so as to be aligned in the Y-axis direction with the movable portion 11 therebetween, but the arrangement positions of the terminal portions 21 and 16 are not limited thereto. For example, as shown in Fig. 13 , the terminal portions 21 and 16 may be respectively provided on the second portions 2 b and 15 b so as to be aligned in the X-axis direction with the movable portion 11 therebetween.

[0104] FIG. 13 is a plan view showing the configuration of the vibration module 3 (optical deflector 3a) according to the fourth modification of the first embodiment.

[0105] According to this configuration, since the terminal portions 21 and 16 are not arranged along the Y axis, the support substrate 2 and the vibration module 3 (optical deflector 3a) can be made smaller in the Y axis direction compared to the first embodiment.

[0106] <Fifth Modification of First Embodiment> In the first embodiment, the opening 2 c of the support substrate 2 has a rectangular shape in a plan view, but the shape of the opening 2 c of the support substrate 2 is not limited to this. For example, as shown in Fig. 14 , an inner edge E11 (see Fig. 6A ) of the first portion 2 a of the support substrate 2 may be disposed outside the boundary line B1 between the connecting portion 14 and the first portion 2 a in a plan view, along the boundary line B1.

[0107] FIG. 14 is a plan view showing the configuration of the vibration module 3 (optical deflector 3a) according to the fifth modification of the first embodiment.

[0108] According to this configuration, the area where the first portion 2 a of the support substrate 2 and the first portion 15 a of the fixing portion 15 overlap in a plan view is wider than in embodiment 1. This allows the support substrate 2 and the first portion 15 a of the fixing portion 15 to be more firmly fixed to each other.

[0109] <Modification 6 of Embodiment 1> In Embodiment 1, in a plan view, the set of the drive unit 12, the connecting unit 14, and the first part 15a is arranged on both sides of the movable unit 11 along the rotation axis R0, but as shown in FIG. 15 , it may be arranged on only one side of the movable unit 11 along the rotation axis R0.

[0110] FIG. 15 is a plan view showing the configuration of the vibration module 3 (optical deflector 3a) according to the sixth modification of the first embodiment.

[0111] In this modified example, compared to the first embodiment, the drive unit 12, connecting unit 14, first portion 15a, and terminal portion 16 on the negative side of the Y axis are omitted from the drive element 1, and the first portion 2a on the negative side of the Y axis is omitted from the support substrate 2. The support substrate 2 includes one first portion 2a overlapped with one first portion 15a of the fixed portion 15, and two second portions 2b connected to the one first portion 2a of the support substrate 2 and overlapped with two second portions 15b of the fixed portion 15.

[0112] According to this modified example, the upper surfaces of the first portion 15a and the second portion 15b of the fixing portion 15 can be used to adhesively fix the first portion 2a and the second portion 2b of the support substrate 2, respectively, and therefore the drive element 1 can be firmly fixed to the support substrate 2. Furthermore, according to this modified example, compared to the first embodiment, the configuration on the Y-axis negative side of the movable portion 11 is omitted, and therefore the support substrate 2 and the vibration module 3 (optical deflector 3a) can be made smaller in the Y-axis direction.

[0113] In the first embodiment, the two first portions 15 a of the fixing portion 15 are connected by the two second portions 15 b. In contrast, in the second embodiment, the two first portions 15 a are connected by the lower cover 17.

[0114] FIG. 16 is a perspective view showing the configuration of a driving element 1 according to the second embodiment.

[0115] 1 , in the second embodiment, the two second portions 15b are omitted from the fixed portion 15, and the lower surfaces of the two first portions 15a (lower surfaces of the material layer 1b) are connected by a lower cover 17. The lower cover 17 is made of, for example, silicon (Si). The lower cover 17 may be processed and molded together with the driving element 1 from a single SOI wafer, or the lower cover 17 molded separately from the driving element 1 may be bonded to the lower surfaces of the two first portions 15a.

[0116] FIG. 17 is a plan view showing the configuration of the vibration module 3 (optical deflector 3a) according to the second embodiment.

[0117] In the second embodiment, the lower surface of the first portion 2 a of the support substrate 2 and the upper surface of the first portion 15 a of the fixing portion 15 are bonded together with an adhesive 24 .

[0118] <Effects of Second Embodiment> In the second embodiment, the electrode pads 16a, 21a are connected when the driving element 1 and the support substrate 2 are adhesively fixed, thereby electrically connecting the support substrate 2 and the driving element 1. Furthermore, because the support substrate 2 is retracted at least from the connecting portion 14 toward the fixed portion 15, the adhesive 24 that bonds the support substrate 2 and the fixed portion 15 is less likely to reach the connecting portion 14. Therefore, the movable portion 11 can be smoothly rotated while the vibration module 3 is miniaturized.

[0119] 16 and 17 , the driving element 1 includes, in a plan view, a pair of a driving unit 12 and a connecting unit 14 on both sides of the movable unit 11 along the rotation axis R0. The fixed unit 15 includes two first portions 15a to which the two connecting units 14 are respectively connected, and a lower cover 17 (second portion) connecting the lower ends of the two first portions 15a.

[0120] With this configuration, the movable part 11 is supported and driven on both sides, thereby enabling stable and efficient driving of the movable part 11. Furthermore, since the lower cover 17 connects the lower ends of the two first parts 15a, the two first parts 15a can be integrated, making the fixed part 15 stronger.

[0121] As shown in Figure 17, the support substrate 2 has two first parts 2a (parts) that are respectively fixed to two first parts 15a of the fixed portion 15, and two second parts 2b (parts) that connect the two first parts 2a (parts) in a direction parallel to the rotation axis R0 (Y-axis direction).

[0122] According to this configuration, the two first portions 15a of the fixed portion 15 are bridged by the strong support substrate 2, so that the drive element 1 can be supported by the support substrate 2 with high rigidity.

[0123] <First Modification of Second Embodiment> The support substrate 2 of the second embodiment includes a pair of second portions 2 b sandwiching the movable portion 11, but one of the two second portions 2 b may be omitted from the configuration of the second embodiment 2. For example, as shown in FIG. 18 , the second portion 2 b on the positive side of the X-axis may be omitted.

[0124] FIG. 18 is a plan view showing the configuration of a vibration module 3 (optical deflector 3a) according to a first modification of the second embodiment.

[0125] The support substrate 2 has two first parts 2a that are respectively fixed to two first parts 15a of the fixed portion 15, and one second part 2b that connects the two first parts 2a in a direction parallel to the rotation axis R0 (Y-axis direction).

[0126] In this configuration, the two first portions 15a of the fixed portion 15 are bridged by the strong support substrate 2, so the drive element 1 can be supported with high rigidity by the support substrate 2. Furthermore, compared to the second embodiment, the second portion 2b on the positive side of the X axis is omitted, so the support substrate 2 and the vibration module 3 (optical deflector 3a) can be made smaller in the X axis direction.

[0127] <Modification 2 of Embodiment 2> The support substrate 2 of Embodiment 2 has a pair of second portions 2b sandwiching the movable portion 11, but as shown in FIG. 19 , both of the two second portions 2b may be omitted from the configuration of Embodiment 2.

[0128] FIG. 19 is a plan view showing the configuration of a vibration module 3 (optical deflector 3a) according to a second modification of the second embodiment.

[0129] In this modified example, two support substrates 2 (first portions 2 a) are respectively fixed to two first portions 15 a of the fixing portion 15. Both of the two support substrates 2 include connection terminals 22 (see FIG. 3 ), and each electrode pad 21 a of the two support substrates 2 is connected to an external drive circuit via the corresponding connection terminal 22 and a flexible printed circuit board FPC.

[0130] In this modified example, the two support substrates 2 are not connected to each other, so the rigidity of the vibration module 3 alone is reduced compared to embodiment 2. However, by installing the two support substrates 2 in the housing 4, as in Figure 9, the rigidity of the vibration module 3 can be increased.

[0131] In this modified example, the vibration module 3 can also be made smaller by using the support substrate 2, and the two support substrates 2 (first portions 2 a) are retracted outward from the connecting portion 14, allowing the movable portion 11 to rotate smoothly. Furthermore, compared to the second embodiment, the two second portions 2 b are omitted, allowing the support substrate 2 and vibration module 3 (optical deflector 3 a) to be made smaller in size in the X-axis direction.

[0132] Third Embodiment In the first and second embodiments, the driving unit 12 is a tuning fork type vibrator, but the driving unit 12 may be a vibrator of another type. In a third embodiment, the driving unit 12 is a meander type vibrator.

[0133] FIG. 20 is a plan view showing the configuration of the vibration module 3 (optical deflector 3a) according to the third embodiment.

[0134] In the third embodiment, compared to the first embodiment shown in Fig. 5 , the pair of torsion units 13 is omitted, and the pair of drive units 12 are meandering vibrators. The drive unit 12 includes four rectangular arm units 12a connected to each other, and two piezoelectric bodies 12b and two piezoelectric bodies 12c installed on the four arm units 12a. The inner end of the drive unit 12 is connected to the movable unit 11, and the outer end of the drive unit 12 is connected to the first portion 15a of the fixed unit 15 via the connecting unit 14. In Fig. 20 , the boundary line B1 between the connecting unit 14 and the first portion 15a is shown by a dotted line for convenience.

[0135] In the third embodiment, similarly to the first embodiment, the support substrate 2 and the fixing portion 15 are fixed to each other by the adhesive 24. The positional relationship between the edge E11 of the support substrate 2 and the edge E21 of the fixing portion 15 is the same as that shown in Fig. 6(a), and the positional relationship between the edge E12 of the support substrate 2 and the edge E22 of the fixing portion 15 is the same as that shown in Fig. 6(b). In addition, a fillet similar to that shown in Figs. 6(a) and 6(b) is formed at the end of the adhesive 24.

[0136] In the third embodiment as well, the electrode pads 16a, 21a are connected when the drive element 1 and the support substrate 2 are adhesively fixed, so that the support substrate 2 and the drive element 1 can be electrically connected without using a separate wiring means such as wire bonding. Furthermore, because the support substrate 2 is retracted at least from the connecting portion 14 toward the fixed portion 15, the adhesive 24 that bonds the support substrate 2 and the fixed portion 15 is less likely to reach the connecting portion 14. Therefore, the movable portion 11 can be smoothly rotated while the vibration module 3 is miniaturized.

[0137] <Other Modifications> The configuration examples of the present invention are not limited to the above-described embodiment and modifications, and various modifications are possible.

[0138] In Modifications 1 to 6 of Embodiment 1, Embodiment 2, Modifications 1 and 2 of Embodiment 2, and Embodiment 3, the support substrate 2 and the fixing portion 15 may also be fixed to each other by adhesive 25 (see Figure 7(a)) or adhesive 26 (see Figure 7(b)).

[0139] In the above embodiment and modified example, adhesive is applied to the entire area where the support substrate 2 and the fixing portion 15 face each other, but as long as sufficient bonding strength between the support substrate 2 and the fixing portion 15 is ensured, adhesive need not be applied to part of the area where the support substrate 2 and the fixing portion 15 face each other. For example, adhesive need not be applied to areas corresponding to the four corners of the fixing portion 15. However, it is preferable that adhesive be applied to at least the peripheral area including the electrode pads 21 a, 16 a, so that the opposing electrode pads 21 a, 16 a are reliably connected to each other.

[0140] In the third modification of the first embodiment, the second portion 2b on the positive side of the X-axis of the support substrate 2 may be omitted. That is, the support substrate 2 may be configured with the first portion 2a and the second portion 2b connected in an L-shape. In this case as well, the first portion 2a and the second portion 2b of the support substrate 2 are fixed to the first portion 15a and the second portion 15b of the fixing portion 15, respectively, so that the drive element 1 can be firmly fixed to the support substrate 2.

[0141] In the above embodiment and modified examples, the outer contour of the first portion 2a of the support substrate 2 may match the outer contour of the first portion 15a of the fixed portion 15 in a planar view. This allows the vibration module 3 (optical deflector 3a) to be miniaturized in the Y-axis direction. Similarly, the outer contour of the second portion 2b of the support substrate 2 may match the outer contour of the second portion 15b of the fixed portion 15 in a planar view. This allows the vibration module 3 (optical deflector 3a) to be miniaturized in the X-axis direction.

[0142] In the above embodiment and modified examples, the shape of the movable part 11 is circular, but the shape of the movable part 11 may be other shapes such as square. The shape of the driving element 1 in a plan view and the dimensions of each part of the driving element 1 can also be changed as appropriate.

[0143] Furthermore, the driving element 1 may be used as an element other than an optical deflector. When the driving element 1 is used as an element other than an optical deflector, the movable part 11 does not need to have the reflecting surface 11 a, and may have another member other than the reflecting surface 11 a.

[0144] In addition, the embodiments of the present invention can be modified in various ways as appropriate within the scope of the technical ideas set forth in the claims.

[0145] (Additional Notes) The above description of the embodiments discloses the following techniques.

[0146] (Technology 1) A vibration module comprising: a driving element; and a support substrate supporting the driving element, wherein the driving element comprises: a movable part; a driving part that rotates the movable part about a rotation axis; a fixed part fixed to a lower surface of the support substrate by an adhesive; a connecting part that connects the driving part to the fixed part; and a first electrode pad installed on an upper surface of the fixed part and connected to a driving source of the driving part by a wiring pattern, wherein a second electrode pad is arranged on the lower surface of the support substrate at a position opposite to the first electrode pad, and the first electrode pad and the second electrode pad are connected, and the support substrate is fixed to the fixed part so that the support substrate is retracted from the connecting part towards the fixed part.

[0147] According to this technology, the first electrode pad and the second electrode pad are connected when the drive element and the support substrate are adhesively fixed, so the support substrate and the drive element can be electrically connected without using a separate wiring method such as wire bonding. This allows the overall configuration of the vibration module to be miniaturized. Furthermore, because the support substrate is retracted from at least the connecting portion toward the fixed portion, the adhesive that bonds the support substrate and the fixed portion is less likely to reach the connecting portion. This prevents the adhesive from interfering with the rotation of the movable portion. Therefore, the movable portion can be smoothly rotated while miniaturizing the vibration module.

[0148] (Technology 2) A vibration module according to Technology 1, characterized in that: the fixed portion comprises a first portion connected to the connecting portion and extending in a direction perpendicular to the rotation axis in a planar view, and a second portion extending from an end of the first portion toward the movable portion in parallel to the rotation axis; the support substrate has a first edge and a second edge that are aligned respectively with a first edge on the inside of the first portion and a second edge on the inside of the second portion in a planar view; the first edge of the support substrate is retracted toward the fixed portion from the first edge of the fixed portion, and the second edge of the support substrate is recessed toward the rotation axis from the second edge of the fixed portion.

[0149] According to this technology, the upper surface of the second portion as well as the upper surface of the first portion of the fixed portion can be used to bond and fix the drive element to the support substrate, thereby firmly fixing the drive element to the support substrate. Furthermore, because the first edge of the support substrate is recessed toward the fixed portion from the first edge of the fixed portion, the adhesive used to bond and fix the support substrate and the first portion is less likely to reach the connecting portion. This allows the movable portion to rotate smoothly. Furthermore, because the second edge of the support substrate is recessed toward the rotation axis from the second edge of the fixed portion, the adhesive used to bond and fix the support substrate and the second portion spreads further along the support substrate. This allows for stronger bonding between the support substrate and the second portion.

[0150] (Technology 3) The vibration module according to Technology 2, wherein the distance between the first edge of the support substrate and the first edge of the fixing portion is greater than 0 mm and equal to or less than 3 mm in plan view.

[0151] According to this technology, by retracting the first edge of the support substrate outward from the first edge of the fixed portion by more than 0 mm, the adhesive is less likely to reach the connecting portion, allowing the movable portion to rotate smoothly. Also, by setting the distance by which the first edge of the support substrate retracts outward from the first edge of the fixed portion to 3 mm or less, the adhesive area between the support substrate and the first portion of the fixed portion can be increased, thereby enabling the support substrate and the first portion to be firmly fixed together.

[0152] (Technology 4) The vibration module according to Technology 2 or 3, wherein in a plan view, the distance between the second edge of the support substrate and the second edge of the fixing portion is greater than 0 mm and equal to or less than 3 mm.

[0153] According to this technology, by retracting the second edge of the fixing portion outward from the second edge of the support substrate by more than 0 mm, it becomes easier to form a fillet on the second edge, and the wetting and spreading effect of the fillet increases the bonding area, thereby strengthening the bond between the support substrate and the fixing portion. Furthermore, the stronger bond increases the robustness of the entire module, and the width of the second portion of the fixing portion can be reduced, allowing the drive element and vibration module to be miniaturized in a direction perpendicular to the rotation axis. Furthermore, by setting the distance that the second edge of the support substrate extends inward from the second edge of the fixing portion to 3 mm or less, the bonding area between the support substrate and the second portion of the fixing portion can be increased, thereby strengthening the bond between the support substrate and the second portion.

[0154] (Technology 5) A vibration module described in any one of technologies 2 to 4, characterized in that the drive element, in a planar view, has a set of the drive section, the connecting section, and the first section on both sides of the movable section along the rotation axis, and the second section connects at least one end of two of the first sections.

[0155] According to this technology, the movable part is supported and driven on both sides, allowing the movable part to be driven stably and efficiently. Furthermore, because the second part connects one end of at least two first parts, the two first parts can be integrated, making the fixed part stronger. Furthermore, by adhesively fixing the second part to the support substrate, the drive element can be supported on the support substrate with high rigidity.

[0156] (Technology 6) In the vibration module according to Technology 5, the two second parts connect both ends of the two first parts, respectively.

[0157] According to this technique, both ends of the first portion are connected to the second portion, thereby making the fixing portion stronger. Furthermore, by adhesively fixing at least one of the two second portions to the support substrate, the driving element can be supported by the support substrate with higher rigidity.

[0158] (Technology 7) In the vibration module described in Technology 6, the support substrate has a first portion that overlaps the first portion of at least one of the fixed portions, and a second portion that overlaps the second portion of at least one of the fixed portions.

[0159] According to this technique, the upper surfaces of the first and second parts of the fixing portion can be used to adhesively fix the driving element to the first and second parts of the support substrate, respectively, thereby enabling the driving element to be firmly fixed to the support substrate.

[0160] (Technology 8) In the vibration module described in Technology 7, the two first portions of the support substrate are respectively arranged to correspond to the two first portions of the fixing portion, and the two second portions of the support substrate respectively connect both ends of the two first portions of the support substrate.

[0161] According to this technique, both ends of the two first portions of the support substrate are connected to the two second portions of the support substrate, respectively, making the support substrate stronger. Furthermore, by adhesively fixing at least one of the two second portions of the fixing part to the second portion of the support substrate, the drive element can be supported by the support substrate with higher rigidity.

[0162] (Technology 9) A vibration module according to Technology 1, characterized in that the driving element, in a plan view, has a set of the driving unit and the connecting unit on both sides of the movable unit along the rotation axis, and the fixed unit has two first parts to which the two connecting units are respectively connected, and a second part connecting the lower ends of the two first parts.

[0163] According to this technology, the movable part is supported and driven on both sides, so that the movable part can be driven stably and efficiently. In addition, because the second part connects the lower ends of the two first parts, the two first parts can be integrated, and the fixed part can be made strong.

[0164] (Technology 10) In the vibration module described in Technology 9, the support substrate has a portion that is fixed to each of the two first portions, and a portion that connects these portions in a direction parallel to the rotation axis.

[0165] According to this technique, the two first portions of the fixed portion are bridged by a strong support substrate, so that the drive element can be supported by the support substrate with high rigidity.

[0166] (Technology 11) In the vibration module described in any one of technologies 1 to 10, the first electrode pad and the second electrode pad are electrically connected by solder, and the adhesive is made of a resin material.

[0167] This technique allows the first electrode pad and the second electrode pad to be firmly connected.

[0168] (Technology 12) The vibration module according to any one of technologies 1 to 10, wherein the adhesive is made of a conductive filler and a resin material.

[0169] This technique makes it easy to arbitrarily set the bonding location between the support substrate and the fixed portion.

[0170] (Technology 13) The vibration module according to any one of Techniques 1 to 12, wherein at least a part of the adhesive is disposed so as to protrude from the support substrate in a plan view.

[0171] According to this technique, the adhesive overflows from the support substrate to form a fillet, which increases the contact area between the adhesive and the support substrate and the fixed portion, thereby enabling the support substrate and the fixed portion to be firmly fixed in that area.

[0172] (Technology 14) An optical deflector comprising: a vibration module according to any one of technologies 1 to 13; and a reflecting surface arranged on the surface of the movable part on the same side as the surface to which the support substrate is fixed, wherein the support substrate is arranged in an area other than the area facing the reflecting surface.

[0173] Since this technology includes the vibration module, it is possible to smoothly rotate the movable part while miniaturizing the optical deflector. Also, light incident from above the support substrate can be made to enter the reflective surface without being blocked by the support substrate, and can be efficiently reflected above the support substrate without being blocked by the support substrate.

[0174] REFERENCE SIGNS LIST 1 Drive element 2 Support substrate 2a First portion 2b Second portion 3 Vibration module 3a Optical deflector 11 Movable portion 11a Reflecting surface 12 Drive portion 12b Piezoelectric body (drive source) 14 Connecting portion 15 Fixed portion 15a First portion 15b Second portion 16a Electrode pad (first electrode pad) 16b Wiring (wiring pattern) 17 Lower cover (second portion) 21a Electrode pad (second electrode pad) 23 Solder 24, 25, 26 Adhesive E11, E21 First edge E12, E22 Second edge R0 Rotation axis

Claims

1. A vibration module comprising a driving element and a support substrate for supporting the driving element, wherein the driving element includes a movable part, a driving part for rotating the movable part about a rotation axis, a fixing part fixed to the lower surface of the support substrate by an adhesive, a connecting part for connecting the driving part to the fixing part, and a first electrode pad disposed on the upper surface of the fixing part and connected to a driving source of the driving part by a wiring pattern; a second electrode pad is disposed on the lower surface of the support substrate at a position facing the first electrode pad; the first electrode pad and the second electrode pad are connected; and the support substrate is fixed to the fixing part such that the support substrate retreats from the connecting part toward the fixing part side.

2. The vibration module according to claim 1, wherein the fixing part includes a first part connected to the connecting part and extending in a direction perpendicular to the rotation axis in a plan view, and a second part extending from an end of the first part toward the movable part side parallel to the rotation axis; the support substrate has a first edge along the inner first edge of the first part and a second edge along the inner second edge of the second part in a plan view; the first edge of the support substrate retreats from the first edge of the fixing part toward the fixing part side, and the second edge of the support substrate enters from the second edge of the fixing part toward the rotation axis side.

3. The vibration module according to claim 2, wherein in a plan view, a distance between the first edge of the support substrate and the first edge of the fixing part is greater than 0 mm and equal to or less than 3 mm.

4. The vibration module according to claim 2, wherein in a plan view, a distance between the second edge of the support substrate and the second edge of the fixing part is greater than 0 mm and equal to or less than 3 mm.

5. The vibration module according to claim 2, wherein in a plan view, the driving element includes a set of the driving part, the connecting part, and the first part on both sides of the movable part along the rotation axis; and the second part connects at least one end of the two first parts.

6. In the vibration module according to claim 5, the two second portions connect the ends of both of the two first portions, respectively. A vibration module characterized by this.

7. In the vibration module according to claim 6, the support substrate includes a first portion that is overlapped with at least one of the first portions of the fixing portion, and a second portion that is overlapped with at least one of the second portions of the fixing portion. A vibration module characterized by this.

8. In the vibration module according to claim 7, the two first portions of the support substrate are respectively arranged corresponding to the two first portions of the fixing portion, and the two second portions of the support substrate connect the ends of both of the two first portions of the support substrate, respectively. A vibration module characterized by this.

9. In the vibration module according to claim 1, in a plan view, the driving element includes a set of the driving portion and the connecting portion on both sides of the movable portion along the rotation axis, and the fixing portion includes two first portions to which the two connecting portions are respectively connected, and a second portion that connects the lower ends of the two first portions. A vibration module characterized by this.

10. In the vibration module according to claim 9, the support substrate has a portion fixed to each of the two first portions and a portion that connects these portions in a direction parallel to the rotation axis. A vibration module characterized by this.

11. In the vibration module according to claim 1, the first electrode pad and the second electrode pad are electrically connected by solder, and the adhesive is made of a resin material. A vibration module characterized by this.

12. In the vibration module according to claim 1, the adhesive is made of a conductive filler and a resin material. A vibration module characterized by this.

13. In the vibration module according to claim 1, at least a part of the adhesive is arranged to protrude from the support substrate in a plan view. A vibration module characterized by this.

14. An optical deflector comprising: the vibration module according to any one of claims 1 to 13; and a reflecting surface disposed on the surface of the movable portion on the same side as the surface to which the support substrate is fixed, wherein the support substrate is disposed in a region other than the region facing the reflecting surface.

Images