阅读说明：本技术 振动装置以及光学检测装置 (Vibration device and optical detection device ) 是由 藤本克己 坂口仁志 于 2018-06-15 设计创作，主要内容包括：提供一种能够使液滴以较大的振幅移动或雾化的振动装置。在振动装置(2)中,穹顶状的盖(11)配置为包含光学检测元件(3)的检测区域,在盖(11)固定有筒状的振动体(12),借助振动体(12)使盖(11)振动的压电元件(13)固定于振动体(12)。振动体(12)具有圆筒部(14)、与圆筒部(14)的第1端部(14a)连结的第1连结部(15)、与第1连结部的盖(11)侧连结的第1环状部(16)、与圆筒部(14)的第2端部连结的第2连结部(17)、以及与第2连结部(17)的连结有圆筒部(14)的一侧的相反侧连结的第2环状部(18)。(Provided is a vibration device capable of moving or atomizing liquid droplets with a large amplitude. In a vibrating device (2), a dome-shaped cover (11) is arranged in a detection region including an optical detection element (3), a tubular vibrating body (12) is fixed to the cover (11), and a piezoelectric element (13) that vibrates the cover (11) via the vibrating body (12) is fixed to the vibrating body (12). The vibrator (12) has a cylindrical portion (14), a 1 st connecting portion (15) connected to a 1 st end portion (14a) of the cylindrical portion (14), a 1 st annular portion (16) connected to a cover (11) side of the 1 st connecting portion, a 2 nd connecting portion (17) connected to a 2 nd end portion of the cylindrical portion (14), and a 2 nd annular portion (18) connected to a side of the 2 nd connecting portion (17) opposite to a side to which the cylindrical portion (14) is connected.)

1. A vibration device, wherein,

the vibration device includes:

a cover having a dome shape and configured to include a detection region of the optical detection element;

a vibrating body having a cylindrical shape, the cover being fixed to the vibrating body; and

a piezoelectric element fixed to the vibrator and vibrating the cover by the vibrator,

the vibrator has:

a cylindrical portion having a 1 st end portion located on the cover side and a 2 nd end portion located on the opposite side of the cover;

a 1 st coupling part which is cylindrical, is coupled to the 1 st end of the cylindrical part, and is formed of a cylinder having an inner diameter larger than that of the cylindrical part;

a 1 st annular portion coupled to the cover side of the 1 st coupling portion, having an inner diameter smaller than an inner diameter of the 1 st coupling portion, and having the cover fixed to a surface on the cover side;

a 2 nd coupling part coupled to the 2 nd end part of the cylindrical part and formed of a cylinder having an outer diameter smaller than that of the cylindrical part; and

a 2 nd annular portion fixed to a surface of the 2 nd coupling portion opposite to the side coupled to the cylindrical portion and having an outer diameter larger than that of the 2 nd coupling portion,

the piezoelectric element is fixed to a surface of the 2 nd annular portion opposite to the side fixed to the 2 nd coupling portion.

2. The vibration device according to claim 1,

the 2 nd end portion of the cylindrical portion is disposed at a position within a range of 1/2 ± 40% of a dimension of the cylindrical vibrator along a direction connecting the 1 st end portion and the 2 nd end portion of the cylindrical portion.

3. The vibration device according to claim 1 or 2,

the 2 nd annular portion has an outer diameter different from an outer diameter of the cylindrical portion.

4. The vibration device according to any one of claims 1 to 3,

(the outer diameter of the 2 nd annular portion-the outer diameter of the cylindrical portion) is in a range of + 16% or less of the outer diameter of the cylindrical portion.

5. The vibration device according to any one of claims 1 to 3,

the vibrating portion formed by the vibrating body and the cover vibrates in a (0, 0) mode.

6. The vibration device according to claim 5,

(the outer diameter of the 2 nd annular portion-the outer diameter of the cylindrical portion) is 0% to 15% of the outer diameter of the cylindrical portion.

7. The vibration device according to any one of claims 1 to 3,

the vibrating portion formed by the vibrating body and the cover vibrates in a (0, 1) mode.

8. The vibration device according to claim 7,

(the outer diameter of the 2 nd annular portion-the outer diameter of the cylindrical portion) is about 0% of the outer diameter of the cylindrical portion, or within a range of 5% to + 15%.

9. The vibration device according to any one of claims 1 to 3,

the vibrating portion formed by the vibrating body and the cover vibrates in a (0, 2) mode.

10. The vibration device according to claim 9,

(the outer diameter of the 2 nd annular portion-the outer diameter of the cylindrical portion) is in a range of-6% to-4% of the outer diameter of the cylindrical portion, or 0% to + 12%.

11. The vibration device according to any one of claims 1 to 10,

the outer diameter of the cylindrical portion is equal to the outer diameter of the 1 st coupling portion.

12. The vibration device according to any one of claims 1 to 11,

the 2 nd annular portion is an annular vibration plate.

13. The vibration device according to claim 12,

the 2 nd annular portion is a flange portion that protrudes outward in the radial direction of the 2 nd coupling portion from the outer peripheral edge of the 2 nd coupling portion.

14. The vibration device according to any one of claims 1 to 13,

the outer diameter of the annular piezoelectric element is equal to the outer diameter of the cylindrical portion.

15. The vibration device according to any one of claims 1 to 14,

the cover is formed of a light-transmitting body.

16. An optical inspection apparatus, wherein,

the optical detection device includes: the vibration device of any one of claims 1 to 15; and an optical detection element disposed in at least a part of an internal space of the tubular vibrating body of the vibrating device, the optical detection element having the detection region in the cover.

17. The optical detection device of claim 16,

the optical detection element is an image pickup element, and the detection area is a field of view.

18. The optical detection device of claim 16,

the optical detection element is an element that optically detects active energy rays.

19. The optical detection device of claim 17,

the active energy ray is at least one of infrared ray and electromagnetic wave.

Technical Field

The present invention relates to a vibration device for removing foreign matter such as water droplets and dust adhering to a dome-shaped cover, and an optical detection device including the vibration device.

Background

Various camera modules have been proposed in which a light-transmitting body is disposed in front of an imaging element of a camera. Patent document 1 discloses such a water droplet removing device for a camera module. Patent document 1 discloses a vibration device having a structure in which a cylindrical body is coupled to a dome-shaped light-transmitting body. Here, a structure vibrating in the (m, n) mode is shown for a dome-shaped light-transmitting body. Here, m is the number of pitch lines existing in the radial direction of the circle diameter, and n is the number of pitch lines existing in the circumferential direction. Patent document 1 shows a (0, 0) mode, a (1, 0) mode, a (0, 1) mode, and a (1, 1) mode.

The water droplets adhering to the surface of the dome-shaped light-transmitting body are removed by vibrating the light-transmitting body in such a mode.

Disclosure of Invention

Problems to be solved by the invention

However, in the case of the vibration device described in patent document 1, it is difficult to sufficiently move the droplets adhering to the dome-shaped light transmitting body, or it takes time to atomize.

The present invention aims to provide a vibration device capable of moving or atomizing liquid droplets with a large amplitude.

Another object of the present invention is to provide an optical detection apparatus having the vibration device.

Means for solving the problems

The vibration device of the present invention includes: a cover having a dome shape and configured to include a detection region of the optical detection element; a vibrating body having a cylindrical shape, the cover being fixed to the vibrating body; and a piezoelectric element fixed to the vibrator and vibrating the cover via the vibrator, the vibrator having: a cylindrical portion having a 1 st end portion located on the cover side and a 2 nd end portion located on the opposite side of the cover; a 1 st coupling part which is cylindrical, is coupled to the 1 st end of the cylindrical part, and is formed of a cylinder having an inner diameter larger than that of the cylindrical part; a 1 st annular portion coupled to the cover side of the 1 st coupling portion, having an inner diameter smaller than an inner diameter of the 1 st coupling portion, and having the cover fixed to a surface on the cover side; a 2 nd coupling part coupled to the 2 nd end part of the cylindrical part and formed of a cylinder having an outer diameter smaller than that of the cylindrical part; and a 2 nd annular portion fixed to a surface of the 2 nd coupling portion opposite to the side connected to the cylindrical portion and having an outer diameter larger than that of the 2 nd coupling portion, the piezoelectric element being fixed to a surface of the 2 nd annular portion opposite to the side fixed to the 2 nd coupling portion.

ADVANTAGEOUS EFFECTS OF INVENTION

With the vibration device of the present invention, it is possible to provide a vibration device that: the dome-shaped cover can be vibrated at a large amplitude, and the movement of the liquid droplets and the atomization of the liquid droplets can be efficiently achieved.

Drawings

Fig. 1 is a perspective view showing an external appearance of a camera according to embodiment 1 of the present invention.

Fig. 2 is a front sectional view of the camera according to embodiment 1 of the present invention.

Fig. 3 is a front sectional view showing the camera of embodiment 1 in an exploded manner.

Fig. 4 is a front cross-sectional view showing a structure in which a dome-shaped cover, a cylindrical vibrator, and a piezoelectric element of the vibration device according to embodiment 1 are coupled together.

Fig. 5 is a perspective view for explaining a piezoelectric element used in embodiment 1.

Fig. 6 is a front sectional view for explaining example 1 of a supporting structure of a vibration device according to embodiment 1.

Fig. 7 is a perspective view for explaining a support member used in the support structure shown in fig. 6.

Fig. 8 is a front sectional view for explaining example 2 of a supporting structure of a vibrator in the vibrating device according to embodiment 1.

Fig. 9 is a perspective view showing a support member used in the support structure shown in fig. 8.

Fig. 10 (a) to 10 (c) are perspective views for explaining examples of polarization structures of annular piezoelectric elements of the piezoelectric vibrator.

Fig. 11 is a schematic diagram for explaining the (m, n) mode.

Fig. 12 (a) and 12 (b) are schematic main sectional views for explaining the vibration posture and the nodal point in the case where the vibration device of embodiment 1 is not displaced and is maximally displaced in the (0, 0) mode, respectively.

Fig. 13 is a schematic front cross-sectional view for explaining a vibration posture at which the vibration device of embodiment 1 is maximally displaced and a position of a node when vibrating in the (0, 1) mode.

Fig. 14 is a schematic front cross-sectional view for explaining a vibration posture at which the vibration device of embodiment 1 is maximally displaced and a position of a node when vibrating in the (0, 2) mode.

Fig. 15 is a graph showing a relationship between the J-dimension ratio and the electromechanical coupling coefficient.

Fig. 16 is a diagram showing a relationship between the J-size ratio and the amplitude ratio in the case of using the (0, 2) mode.

Fig. 17 is a diagram showing a relationship between the J-size ratio and the amplitude ratio in the case of using the (0, 1) mode.

Fig. 18 is a diagram showing a relationship between the J-size ratio and the amplitude ratio in the case of using the (0, 0) mode.

Detailed Description

The present invention will be made clear by the following description of specific embodiments of the present invention with reference to the accompanying drawings.

Fig. 1 is a perspective view showing an external appearance of a camera according to embodiment 1 of the present invention, and fig. 2 is a front sectional view of the camera according to embodiment 1.

The camera 1 has a camera main body 3 and a vibration device 2 as a water droplet removing device. The camera body 3 is fixed to the base plate 4. An imaging unit 5 is provided at the upper end of the camera body 3. The imaging unit 5 incorporates a circuit including an imaging element. Further, a lens module 6 is fixed to an upper end of the image pickup unit 5. A cylindrical housing member 7 is provided on the bottom plate 4. A part of the vibration device 2 enters the housing member 7.

The vibration device 2 has a dome-shaped cover 11. The dome-shaped cover 11 is formed of a light-transmitting body such as glass or plastic. The dome-shaped cover 11 may be formed of a transparent body only in a portion located in front of the field of view of the camera.

In the vibration device 2, a tubular vibration body 12 is fixed to a dome-shaped cover 11. A piezoelectric element 13 is fixed to the lower end side of the tubular vibrating body 12. By driving the piezoelectric element 13, the entire vibrating portion formed by the piezoelectric element 13, the vibrator 12, and the cover 11 is vibrated.

The 1 st coupling part 15 and the 2 nd coupling part 17 have a cylindrical shape. The 1 st and 2 nd annular portions 16 and 18 are annular plates. The annular plate means that the radial dimension of the annular plate is larger than the thickness. Of course, the 1 st annular portion 16 and the 2 nd annular portion 18 are not limited to such annular plates.

The vibrator 12 has a cylindrical portion 14, a 1 st connecting portion 15, a 1 st annular portion 16, a 2 nd connecting portion 17, and a 2 nd annular portion 18. As shown in fig. 2, in the present embodiment, the cylindrical portion 14, the 1 st connecting portion 15, the 1 st annular portion 16, the 2 nd connecting portion 17, and the 2 nd annular portion 18 are integrally formed such that their central axes are on a concentric axis. In fig. 2, the boundary portion of the above members is indicated by a broken line. Of course, the above configuration may be configured by joining members that are relatively independent of each other.

The cylindrical portion 14 has a 1 st end portion 14a on the cover 11 side and a 2 nd end portion 14b on the opposite side from the cover 11. The 1 st coupling portion 15 is coupled to the 1 st end portion 14 a. A 1 st annular portion 16 is coupled to the 1 st coupling portion 15 on the cover 11 side. The cap 11 is fixed to the cap 11-side surface of the 1 st annular portion 16. The 2 nd coupling portion 17 is coupled to the 2 nd end portion 14 b. A 2 nd annular portion 18 is fixed to a surface of the 2 nd coupling portion 17 opposite to the side coupled to the cylindrical portion 14.

Here, the inner diameter of the 1 st coupling part 15 is larger than the inner diameter of the cylindrical part 14. The outer diameter of the 1 st coupling part 15 is equal to the outer diameter of the cylindrical part 14. The 1 st annular portion 16 has an inner diameter smaller than that of the 1 st coupling portion 15. The outer diameter of the 1 st annular portion 16 is equal to the outer diameter of the cylindrical portion 14. That is, the 1 st coupling portion 15 is provided on the outer peripheral side of both the 1 st annular portion 16 and the cylindrical portion 14 between the 1 st annular portion 16 and the cylindrical portion 14. Therefore, the 1 st annular portion 16 has a shape protruding radially inward from the end of the 1 st coupling portion 15 on the cover 11 side. The 1 st ring part 16 is a ring-shaped vibrating plate.

On the other hand, the 2 nd coupling part 17 has a cylindrical shape, and the inner diameter of the 2 nd coupling part 17 is equal to the inner diameter of the cylindrical part 14. The outer diameter of the 2 nd coupling part 17 is smaller than the outer diameter of the cylindrical part 14.

The 2 nd coupling portion 17 is disposed such that the inner peripheral surface thereof is flush with the inner peripheral surface of the cylindrical portion 14.

On the other hand, the 2 nd annular portion 18 has an outer diameter larger than that of the 2 nd coupling portion 17. The inner diameter of the 2 nd annular portion 18 is equal to the inner diameter of the 2 nd coupling portion 17. The inner peripheral surface of the 2 nd annular portion 18 is flush with the inner peripheral surface of the 2 nd coupling portion 17. That is, the 2 nd coupling part 17 is provided between the cylindrical part 14 and the 2 nd annular part 18 on the inner circumferential side of both the cylindrical part 14 and the 2 nd annular part 18 and on the inner diameter side of the 1 st coupling part 15. Therefore, in the vibrating device 2, the tubular vibrating body 12 has a substantially S-shaped cross-sectional shape in the radial cross-section shown in fig. 2.

The 2 nd annular portion 18 has an outer diameter larger than that of the cylindrical portion 14. In the present embodiment, the 2 nd annular portion 18 is an annular vibrating plate. More specifically, the 2 nd annular portion 18 is a flange portion that protrudes outward in the radial direction of the 2 nd coupling portion 17 from the outer peripheral edge of the 2 nd coupling portion 17.

The piezoelectric element 13 has a ring shape. In the vibration device 2, the ring-shaped piezoelectric element 13 is driven to vibrate the piezoelectric element 13 in the vertical direction. As a result, the cylindrical vibrating body 12 and the lid 11 fixed to the annular piezoelectric element are vibrated.

Fig. 3 is an exploded front sectional view for explaining the configuration of the video camera 1.

Fig. 4 is a front sectional view showing a structure in which the tubular vibrating body 12, the piezoelectric element 13, and the cover 11 are coupled together.

Fig. 5 is a perspective view showing the piezoelectric element 13. The piezoelectric element 13 includes an annular piezoelectric body 13a and electrodes 13b and 13c fixed to one main surface and the other main surface of the piezoelectric body 13a, respectively. Here, the annular piezoelectric body 13a has an annular shape. Of course, the shape may be other than circular. The piezoelectric body 13a may not be annular. The piezoelectric element may have a structure in which a plurality of rectangular plate-shaped piezoelectric bodies are arranged in the circumferential direction. As described later with reference to fig. 10, the piezoelectric bodies 13a differ in polarization direction in the thickness direction among a plurality of regions arranged in the circumferential direction. Thus, when an alternating electric field is applied between the electrodes 13b and 13c, the piezoelectric body 13a vibrates so as to undulate in the vertical direction.

Fig. 6 is a front sectional view showing a 1 st example of a support structure for supporting the structure shown in fig. 4 from the outside. The support plate 21 shown in fig. 7 is used here. The support plate 21 includes a plate main body 21a and a cylindrical support wall 21b surrounding a circular opening 21c provided in the plate main body 21 a. The support wall 21b is provided integrally with the plate main body 21 a. The lower surface of the cylindrical portion 14 is disposed on the upper end surface of the support wall 21b, whereby the vibrating body 12 is supported.

Fig. 8 is a front sectional view of example 2 for explaining a structure for supporting the vibrator 12 from the outside. Fig. 9 is a perspective view showing a support member used in the support structure shown in fig. 8. The support member 22 has a rectangular plate-like shape and a circular opening 22a at the center. As shown in fig. 8, the inner peripheral end surface of the support member 22 abuts against the side surface of the cylindrical portion 14. Thereby, the vibrator 12 is supported by the support member 22.

The structure of supporting the vibrator 12 is not limited to the above-described 1 st and 2 nd examples.

Fig. 10 (a) to 10 (c) are perspective views for explaining examples of the polarization structure of the piezoelectric element. Fig. 10 shows only the piezoelectric body 13a shown in fig. 5, and shows the polarization direction of each region.

In fig. 10 (a) to 10 (c), the region of + indicates a region in which the polarization axis is in a direction from the lower surface to the upper surface in the thickness direction of the piezoelectric body 13 a. Conversely, the region of-indicates a region in which the polarization axis is in a direction from the upper surface toward the lower surface in the thickness direction of the piezoelectric body 13 a.

In fig. 10 (a), all the polarization directions of the regions arranged in the circumferential direction are the same direction.

On the other hand, in fig. 10 (b), of the 4 regions divided into 4 portions in the circumferential direction, the polarization directions of the regions on both sides facing each other with the center interposed therebetween are opposite.

In fig. 10 (c), of the 4 regions divided into 4 portions in the circumferential direction, the regions on both sides facing each other with the center interposed therebetween have the same polarization direction.

When the piezoelectric body 13a shown in fig. 10 (a) is used, when the vibration device 2 is vibrated by driving the annular piezoelectric element, vibration in a (0, 0) mode, which will be described later, is excited in the dome-shaped cover 11. On the other hand, in the case of using the piezoelectric body 13a of the polarization structure shown in fig. 10 (b), vibration of the (0, 1) mode is excited in the dome-shaped cover 11.

When the piezoelectric body 13a of the polarization structure shown in fig. 10 (c) is used, the dome-shaped cover 11 is excited in the (0, 2) mode.

In the vibration device 2 of the present embodiment, the above-described (0, 0) mode, (0, 1) mode or (0, 2) mode is used. This will be described in more detail later. In addition, as described above, m of the (m, n) pattern is the number of pitch lines existing in the radial direction, and n is the number of pitch lines existing in the circumferential direction. m and n are integers.

The (m, n) mode is schematically shown in fig. 11. Here, the phase of the vibration of the region in the cover 11 when the cover 11 is viewed in plan is shown. Such a case is shown in fig. 11: the region marked with + and the region marked with-vibrate in a phase-reversed manner.

In the vibration device of the present invention, the (0, 0) mode, (0, 1) mode, and (0, 2) mode among such (m, n) modes are utilized.

Fig. 12 (a) and 12 (b) are schematic main sectional views for explaining the vibration posture and the nodal point in the case where the vibration device of embodiment 1 is not displaced and is maximally displaced in the (0, 0) mode, respectively. The arrow in (b) of fig. 12 indicates the position of the node of the vibration.

As shown in fig. 12 (b), in the (0, 0) mode, the displacement is maximized at the center of the dome-shaped cover 11. Therefore, the liquid adhering to the vicinity of the center of the cover 11 can be moved greatly. In addition, the liquid attached to the center can be easily atomized.

Fig. 13 is a schematic front cross-sectional view showing the vibration posture in the maximum displacement state and the position of the node of the vibration in the case of performing vibration in the (0, 1) mode. Here, the node position of the vibration is also indicated by an arrow. In the (0, 1) mode, the center to one side of the cover 11 and the center to the other side of the cover 11 are alternately greatly displaced. Therefore, droplets adhering to the outer surface of the dome-shaped cover 11 can be dispersed and atomized to positions other than the center of the cover 11 by the (0, 1) mode. Further, by switching the vibration mode, a small number of droplets remaining in the drive region can be atomized at the center, and the droplets can be removed without increasing the amplitude. Fig. 14 is a schematic front cross-sectional view showing the vibration posture in the maximum displacement state and the position of the node of the vibration when the vibration is performed in the (0, 2) mode. In the (0, 2) mode shown in fig. 14, the droplets can be moved in a sufficiently dispersed manner to a position other than the center of the cover 11 in the vicinity of the droplets, as in the case of the (0, 1) mode. Further, the droplets remaining in the nodes can be atomized at the center, and the droplets can be removed without increasing the amplitude.

In addition, in the (0, 0) mode, no node of vibration is generated in the cover 11. Thus, the field of view can be ensured. In any of the (0, 0) mode, the (0, 1) mode, and the (0, 2) mode, no node extending in the circumferential direction exists in the cover 11. This is because the radial cross section of the vibrating body 12 has an S-shaped configuration. That is, with such a configuration, nodes extending in the circumferential direction in the (1, 0) mode, the (1, 1) mode, and the (1, 2) mode move toward the thickness direction intermediate portion of the vibration body 12. In the case of one piece of the annular vibrating body, nodes extending in the circumferential direction exist in the cover. In contrast, in the present embodiment, since the node has the radial cross section of the S-shape, nodes other than the radial direction can be positioned outside the field of view.

In the present invention, the 2 nd end portion 14b of the cylindrical portion 14 is disposed at a position within 1/2 ± 40% of the dimension of the cylindrical vibrating body 12 along the direction connecting the 1 st end portion 14a and the 2 nd end portion 14b of the cylindrical portion 14 (the direction in which the central axis of the cylindrical portion 14 extends). Therefore, the support structure shown in fig. 6 and the support structure shown in fig. 8 can support the tubular vibrating body 12 of the vibrating device 2 without inhibiting the vibration.

The present inventors have found that, in the above-described vibration device 2, when the outer diameter of the 2 nd annular portion 18 is J and the outer diameter of the cylindrical portion 14 is D, the lid 11 can be greatly vibrated if the J dimension ratio represented by (J-D)/D is within a specific range. This will be described with reference to fig. 15 to 18.

Fig. 15 is a graph showing the relationship between the J-size ratio and the electromechanical coupling coefficient in the (0, 2) mode, the (0, 1) mode, and the (0, 0) mode. The electromechanical coupling coefficient represents the efficiency of converting an electrical input into a mechanical output, and is calculated using the frequency bandwidth of the resonator as an index. When the electromechanical coupling coefficient is small, the amplitude is drastically reduced by a slight frequency deviation even if the peak value of the amplitude is the same. Thus, it is difficult to maintain the amplitude. In fig. 15, lines A, B and C indicate values of the (0, 0) mode, the (0, 2) mode, and the (0, 1) mode, respectively, when the outer diameter of the 2 nd coupling part is D. A lower line A, B or C indicates that the 2 nd link need not be provided. Therefore, in order to obtain the effect of the S-shaped cross-sectional structure, it is preferable to select the J-size having a higher coupling coefficient than the line A, B or C.

Thus, in the (0, 0) mode, the J size ratio is preferably in the range of-16% or more and + 19% or less. In the (0, 2) mode, the content is preferably in the range of-8% to + 16%. In the (0, 1) mode, the J size ratio is preferably in the range of-3% or more and + 20% or less.

Therefore, in the case of using the vibration device 2 of the above 3 modes, it is preferable to set the J-size ratio to + 16% or less. Further, the J size ratio is preferably-3% or more.

Fig. 16 is a diagram showing a relationship between the J-size ratio and the amplitude ratio (%) when vibration is performed in the (0, 2) mode. Here, the amplitude ratio (%) is an amplitude increasing/decreasing rate (%) with reference to the amplitude when J is D.

In fig. 16, the solid line indicates the result when the thickness of the 2 nd annular portion 18, which is a metal plate, is 0.5t, and the broken line indicates the result when the thickness of the 2 nd annular portion 18, which is a metal plate, is 1.0 t. Wherein t is 1.0 mm.

As is clear from fig. 16, even if the thickness of the 2 nd annular portion 18 is changed, in any thickness, a large amplitude can be obtained when the J dimension ratio is in the range of-6% or more and-4% or less on the minus side and 0% or more and 12% or less on the plus side.

Fig. 17 is a diagram showing a relationship between the J-size ratio and the amplitude ratio (%) when vibration is performed in the (0, 1) mode. Here, the thickness of the metal plate as the 2 nd annular portion 18 was 0.5 t.

As is clear from fig. 17, when the (0, 1) mode is used, the J-size ratio is preferably about 0% or in the range of 5% to 15%. Thereby, a relatively large amplitude can be obtained.

Fig. 18 is a diagram showing a relationship between the J-size ratio and the amplitude ratio (%) when vibration is performed in the (0, 0) mode.

As is clear from fig. 18, when the (0, 0) mode is used, the J-size ratio is preferably in the range of 0% to 12%. In this case, a relatively large amplitude can be obtained.

As is clear from fig. 15 to 18, in the present invention, it is preferable that the vibrating portion formed by the dome-shaped cover is vibrated in the (0, 0) mode, the (0, 1) mode, or the (0, 2) mode, and in this case, it is preferable that the J-dimension ratio is in the range of 5% to 12%. This can remove droplets such as water droplets adhering to the outer surface of the cover 11 by moving them greatly and atomizing them.

Of course, when only one or two of the (0, 0) mode, the (0, 1) mode, and the (0, 2) mode are used, the respective preferable ranges of the J-size ratios shown in fig. 16 to 18 may be used.

The J-dimension ratio is preferably 5% or more and 15% or less, but in the present invention, the cap 11 can be vibrated in the (0, 0) mode, (0, 1) mode, or (0, 2) mode as described above as long as the outer diameter of the 2 nd annular portion 18 is different from the outer diameter of the cylindrical portion 14. The 2 nd annular portion 18 is preferably formed to have an outer diameter slightly different from the outer diameter of the cylindrical portion 14, whereby the electromechanical coupling coefficient can be stabilized.

In the above-described embodiment, the image pickup device is used as the optical detection device, and the detection region is the field of view, but the optical detection device may be a device that optically detects active energy. In this case, for example, at least one of infrared rays and electromagnetic waves can be suitably used as the active energy ray.

The optical detection device of the present invention includes the vibration device and the optical detection element disposed in at least a part of the internal space of the tubular vibrating body of the vibration device and having the detection region in the cover, and therefore, the optical detection device of the present invention is not limited to the camera.

Description of the reference numerals

1. A camera; 2. a vibrating device; 3. a camera main body; 4. a base plate; 5. an image pickup unit; 6. a lens module; 7. a housing member; 11. a cover; 12. a vibrating body; 13. a piezoelectric element; 13a, a piezoelectric body; 13b, 13c, electrodes; 14. a cylindrical portion; 14a, 14b, 1 st end, 2 nd end; 15. 1 st connecting part; 16. the 1 st annular part; 17. a 2 nd connecting part; 18. a 2 nd annular part; 21. a support plate; 21a, a plate main body; 21b, a support wall; 21c, an opening part; 22. a support member; 22a, an opening.