VIBRATION DEVICE AND IMAGING DEVICE

Abstract

A vibration device that has the following features: a vibrating body with a translucent section having a first and second principal surface opposite each other, and a vibrating section continuous with the translucent section and vibrating together with the translucent section with a principal vibration; and a piezoelectric vibration element that is fixed to the vibration section; wherein a plurality of localized vibration sections, which generate a localized vibration that differs from the main vibration, are provided at a position that does not overlap with a center of the translucent section.

Description

Technical field

[0001] The present invention relates to a vibration device for setting a vibrating body, comprising a translucent section, into vibration, and to an image-generating device comprising the vibration device. Background technology

[0002] Several existing cameras have been proposed that incorporate a function for removing water droplets, such as raindrops. In patent document 1, shown below, a dome-shaped cover is arranged in front of a camera body. A cylindrical section is connected to the dome-shaped cover. A piezoelectric vibrating element is fixed to the cylindrical section. The piezoelectric vibrating element is caused to vibrate when water droplets adhere to the dome-shaped cover. With this configuration, the cylindrical section and the dome-shaped cover are set into vibration, and the water droplets are removed from the dome-shaped cover.

[0003] In contrast, patent document 2, shown below, depicts an ultrasonic transducer, an adhesive layer section, and an outer lens positioned in front of a camera. When water droplets adhere to the outer lens, an alternating current signal voltage is applied to the ultrasonic transducer. This causes the ultrasonic transducer to vibrate, and the outer lens, which is connected to the ultrasonic transducer, also vibrates. As a result, the water droplets adhering to the outer lens are removed. Reference list patent document Patent document 1: Japanese unexamined patent application publication no. 2012-138768 Patent document 2: Japanese unexamined patent application publication no. 2007-82062

[0004] US 2003 / 0214588A1 discloses a camera comprising an image-capturing device that receives an image signal corresponding to the rays directed onto a photoelectric transducer surface; a dust shield with an overall circular or polygonal plate shape, having a transparent section in an area with at least one predetermined extent in the radial direction from the center and located opposite the front of the optical device at a predetermined distance; a vibrating element arranged annularly on a circumferential section of the dust shield, which exerts vibrations on the dust shield;a sealing structure forming a spatial section that is substantially sealed against a section formed by the opposition of the image-taking device and the dust protection element, by sealing the spatial section against the circumferential sections of the image-taking device and the dust protection element; and an image signal processing circuit that converts an image signal received from the image-taking device, corresponding to an image produced on the photoelectric transducer surface of the image-taking device, into a signal suitable for recording. Brief description of the invention: Technical problem

[0005] To reliably remove water droplets or similar substances from the camera with the water droplet removal function disclosed in Patent Document 1 and Patent Document 2, it is necessary to strongly vibrate the domed cover or the outer lens. However, since the materials and shapes of the domed cover, the outer lens, or similar components vary, it is difficult to reliably remove the water droplets adhering to them. Furthermore, if a mixture of water and soil, such as mud, is present, it may not be reliably removed.

[0006] One object of the present invention is to provide a vibration device capable of readily moving and atomizing water droplets or the like adhering to a translucent section of a vibrating body. A further object of the invention is to provide an image-generating device equipped with the vibration device according to the present invention. Solution to the problem

[0007] A vibration device according to the present invention comprises: a vibrating body with a translucent section having a first and second main surface opposite each other, and a vibration section continuous with the translucent section and vibrating together with the translucent section in a main vibration; and a piezoelectric vibration element fixed to the vibration section in which a plurality of localized vibration sections, generating a localized vibration different from the main vibration, are provided at a position that does not overlap with the center of the translucent section.

[0008] In a specific aspect of the vibration device according to the present invention, the piezoelectric vibration element is fixed to the vibration section of the vibration body, so that the main vibration and the localized vibration are excited.

[0009] In another specific aspect of the vibration device according to the present invention, the localized vibration section is provided in the transparent section and differs from the remaining section of the transparent section at least in its modulus of elasticity, density, and Poisson's ratio. In this case, it is possible to configure the localized vibration section simply by configuring it such that it differs from the remaining section at least in its modulus of elasticity, density, and Poisson's ratio.

[0010] In yet another specific aspect of the vibration device according to the present invention, the localized vibration section is provided within the translucent section and is a thin section having a thickness less than the thickness of the remaining portion of the translucent section. In this case, the localized vibration section can be provided simply by providing the thin portion within the translucent section.

[0011] In another specific aspect of the vibration section according to the present invention, only either the first or the second main surface of the translucent section in the thin section is provided with a recessed section. In this case, the localized vibration section can be provided by providing only the recessed section on at least either the first or the second main surface.

[0012] In yet another specific aspect of the vibration device according to the present invention, the recessed section is provided on the first main surface. In this case, by positioning the second main surface in an outer section, it is possible to readily atomize water droplets or the like that adhere to the second main surface, which is not provided with the recessed section.

[0013] In yet another specific aspect of an elastic wave device according to the present invention, the localized vibration section is made of a material that differs from the material of the remaining section of the translucent section. In this case, it is possible to configure the localized vibration section by providing only a section made of the other material.

[0014] In yet another specific aspect of the elastic wave device according to the present invention, the localized vibration section is provided within the vibration section.

[0015] In another specific aspect of the vibration device according to the present invention, the localized vibration segment has a planar, circular shape. In this case, the localized vibration is hardly dispersed. Thus, the amplitude of the localized vibration can be increased.

[0016] Another specific aspect of the vibration device according to the present invention is that the number of localized vibration sections is even. In this case, two sets of localized vibration sections oscillating in opposite phases can be provided.

[0017] In yet another specific aspect of the vibration device according to the present invention, the vibration body comprises a tubular main body and a lid section that closes an opening of the tubular main body, and the translucent section is provided in the lid section.

[0018] In yet another specific aspect of the vibration device according to the present invention, the vibration body has a rectangular plate shape.

[0019] In yet another specific aspect of the vibration device according to the present invention, a drive circuit for driving the piezoelectric vibration element is also included.

[0020] A further specific aspect of the vibration device according to the present invention includes a drive frequency changer for changing the frequency of a drive signal of the piezoelectric vibration element. In this case, it is possible to effectively excite the piezoelectric vibration element with a main vibration mode and a localized vibration mode by changing the frequency of the drive signal.

[0021] An image-generating device according to the present invention comprises the vibrating device configured according to the present invention and an image-generating element provided to face the first main surface for receiving an outer surface of the second main surface of the vibrating body of the vibrating device. In this case, the water droplets or the like adhering to the second main surface can be readily moved and atomized in the translucent section.

[0022] In yet another specific aspect of the image-generating device according to the present invention, the localized vibration section is positioned outside the field of view of the image-generating element. In this case, water droplets or the like adhering to the translucent section can easily be moved out of the field of view and removed. Advantageous effects of the invention

[0023] According to a vibration device and an image-generating device comprising the vibration device according to the present invention, water droplets or the like adhering to a translucent section can be moved and atomized without further ado. Brief description of the drawings Fig. Figure 1 is a cross-sectional front view of an image generation device according to a first embodiment of the present invention. Fig. Figure 2 is a perspective partial sectional view to illustrate a tubular main body and a piezoelectric vibration element fixed to the tubular main body in a vibration device according to the first embodiment of the present invention. Fig. Figure 3 is a perspective view of a cover section in which a localized vibration section is provided, as seen from a first main surface side in the vibration device according to the first embodiment of the present invention. Fig. Figure 4 is a top view to illustrate an electrode provided on the piezoelectric vibration element. Fig. 5(a) are schematic top views to illustrate a vibration mode up to Fig. 5(d) in the lid section. Fig. Figure 6 is a schematic top view to illustrate a localized vibration to be excited in the first embodiment of the present invention. Fig. Figure 7 is a schematic top view to illustrate a principal vibration mode excited in the vibration device according to the first embodiment of the present invention. Fig. Figure 8 is a diagram showing a relationship between the frequency of a drive signal and the response of the vibration mode excited in the vibration device according to the first embodiment of the present invention. Fig. Figure 9 is a diagram representing a displacement distribution of a localized vibration mode excited in the vibration device according to the first embodiment of the present invention. Fig. Figure 10 is a diagram showing a displacement distribution of the localized vibration mode excited in the vibration device according to the first embodiment of the present invention. Fig. Figure 11 is a schematic top view to illustrate the localized vibration section according to a variation of the first embodiment of the present invention. Fig. Figure 12 is a cross-sectional front view to illustrate a second variation of the localized vibration section of the vibration device according to the first embodiment of the present invention. Fig. Figure 13 is a cross-sectional front view to illustrate a third variation of the localized vibration section of the vibration device according to the first embodiment of the present invention. Fig. Figure 14 is a cross-sectional front view to illustrate a fourth variation of the localized vibration section of the vibration device according to the first embodiment of the present invention. Fig. Figure 15 is a cross-sectional front view of the localized vibration section of the vibration device according to a second embodiment of the present invention. Fig. Figure 16 is a cross-sectional front view of the vibration device according to a third embodiment of the present invention. Fig. Figure 17 is an expanded perspective view of the vibration device according to a fourth embodiment of the present invention. Fig. Figure 18 is a perspective view to illustrate the localized vibration section of the vibration device according to the fourth embodiment of the present invention. Fig. Figure 19 is a perspective view to illustrate a fifth variation of the localized vibration section of the vibration device according to the first embodiment of the present invention. Fig. Figure 20 is a top view to illustrate a sixth variation of the localized vibration section of the vibration device according to the first embodiment of the present invention. Fig. Figure 21 is a top view to illustrate a seventh variation of the localized vibration section of the vibration device according to the first embodiment of the present invention. Description of the exemplary implementations

[0024] The present invention is explained below by descriptions of specific embodiments of the present invention with reference to the accompanying drawings.

[0025] It should be clear that each of the embodiments described in this description is exemplary and that partial substitution or combination of configurations is also possible between different embodiments.

[0026] Fig. Figure 1 is a cross-sectional front view of an image generation device according to a first embodiment of the present invention.

[0027] An image-generating device 1 comprises an image-generating element 2. The image-generating element 2 is a widely used, existing, general-purpose image-generating element for converting an image into an electrical signal. A lens housing body 4, which accommodates a plurality of lenses 3a to 3c, is provided in front of the image-generating element 2. The image-generating element 2 is supported by a mounting section 5. A lower end of the mounting section 5 is connected to a base plate 6.

[0028] The image-generating element 2 and the lens housing body 4 described above are arranged in a vibration device 11 according to the first embodiment. The vibration device 11 comprises a vibration body 12 and a piezoelectric vibration element 13.

[0029] In the present embodiment, the vibrating body 12 comprises a tubular main body 14 with a cylindrical shape as the excitation section and a cover section 15 that closes an opening in an upper region of the tubular main body 14.

[0030] Fig. Figure 2 is a perspective partial sectional view showing a structure in which a tubular main body 14, a piezoelectric vibration element 13, and a support section 16 are laminated. The piezoelectric vibration element 13 is fixed to a lower surface of the tubular main body 14. More precisely, a donut-shaped recessed section 16a is provided on an upper surface of the cylindrical support section 16. The piezoelectric vibration element 13 is located within the recessed section 16a. The piezoelectric vibration element 13 is positioned and fixed between the support section 16 and the tubular main body 14.

[0031] On the other hand, the lid section 15 has a disc-like shape. As can be seen in Fig. As shown in Figure 1, the lid section 15 has a first and second main surface 15a and 15b, which are opposite each other. In the present embodiment, the lid section 15 is made of transparent synthetic resin. Other translucent materials, such as transparent glass or the like, can also be used.

[0032] In the present embodiment, the entire cover section 15 is manufactured as a translucent section. However, the central region of the cover section can be manufactured as a translucent section, and an outer section of the translucent section can be a section that does not transmit light.

[0033] Of the first and second principal surfaces 15a and 15b, which are opposite each other, the first principal surface 15a is arranged to face the lens housing body 4. Thus, an outer surface section of the second principal surface 15b can be imaged by a camera containing the image-generating element 2.

[0034] It should be noted that the image-generating element is not particularly limited and a CCD, a CMOS radar (RADAR), a LIDER or the like can be used.

[0035] Meanwhile, in the present embodiment, the cover section 15 has a transparent first disc-shaped plate 17 and a second disc-shaped plate 18 connected to the first disc-shaped plate 17. The first disc-shaped plate 17 and the second disc-shaped plate 18 are made of a transparent glass material or transparent synthetic resin. Furthermore, the second disc-shaped plate 18 has a plurality of through-holes. As a result, the cover section 15 is provided with recessed sections 18a and 18b, which are open on a lower surface side, that is, on one side of the first main surface 15a. Fig. Figure 3 is a perspective view of the cover section 15 as seen from the side of the first main surface 15a. The cover section 15 has a disc-like shape and features a plurality of recessed sections 18a to 18d. The recessed sections 18c and 18d are also formed by providing through-holes in the second disc-shaped plate 18.

[0036] Accordingly, in the cover section 15, the section where the excluded sections 18a to 18d are each provided is a thin section compared to the remaining section. This thin section causes a localized vibration, which is described below. Therefore, the section where the excluded sections 18a to 18d are each provided is a localized vibration section that generates the localized vibration.

[0037] It should be noted that in the vibration device 11, the entire cover section 15, described above, is manufactured as the translucent section, and the tubular main body 14, which forms the excitation section, is continuous with the translucent section. Both the cover section 15, which is the translucent section, and the tubular main body 14 are configured to vibrate.

[0038] In the present embodiment, the cover section 15 is fixed to the tubular main body 14. The fixing structure is not particularly restricted. The cover section 15 can be fixed to the tubular main body 14 using an adhesive. Alternatively, screws screwed together can be provided on an outer circumferential surface of the cover section 15 or on an inner circumferential surface of an end section of the tubular main body 14. The cover section 15 and the tubular main body 14 can be integrated by screws. Alternatively, the cover section 15 and the tubular main body 14 can be formed in one piece from the same material.

[0039] The piezoelectric vibration element 13 comprises ring-shaped piezoelectric elements 21 and 21. Ring-shaped piezoelectric element 21 and ring-shaped piezoelectric element 21 are laminated with an annular metal plate 22, which is sandwiched between them. The annular metal plate 22 also serves as a terminal connected to an electrical potential. Electrodes 23 and 24, as the other terminals, are provided on the outer surfaces of ring-shaped piezoelectric elements 21 and 21, respectively, in the lamination direction.

[0040] Fig. Figure 4 is a top view to illustrate one shape of electrode 23. As it is in Fig. As shown in Figure 4, the electrode 23 is provided with a ring shape on an upper surface of the ring-shaped piezoelectric element 21. Similarly, the one shown in Figure 4 has a ring shape on the upper surface of the ring-shaped piezoelectric element 21. Fig. The electrode 24 shown in Figure 1 also has a ring shape.

[0041] The ring-shaped piezoelectric elements 21 and 21 are uniformly subjected to a polishing treatment in the thickness direction. However, one ring-shaped piezoelectric element 21 and the other ring-shaped piezoelectric element 21 are subjected to the polishing treatment in the opposite direction, in the thickness direction. A driving signal of an alternating current signal is applied to the piezoelectric vibrating element 13 described above. As a result, the piezoelectric vibrating element 13 expands and contracts, thereby causing a change in volume. This excites a longitudinal vibration and a respiratory vibration. The tubular main body 14, as the vibrating section to which the piezoelectric vibrating element 13 is attached, vibrates, and the lid section 15 also vibrates together with the tubular main body 14. When the lid section 15 vibrates, vibrations in different vibration modes can occur.

[0042] Fig. 5(a) to Fig. Figure 5(d) shows schematic top views to illustrate the vibration modes in cover section 15. Fig. 5(a) to Fig. Figure 5(d) shows a white section and a diagonally hatched section, regions that are shifted in opposite phases. Therefore, a boundary between the white section and the diagonally hatched region becomes a vibration node. For example, in the vibration mode shown in Fig. As shown in 5(b), the outer circumference A of the diagonally hatched region is a node of vibration.

[0043] A mechanical resonance wave type of a circular component can be expressed as (m, n). Here, m is the number of lines of nodes that lie in a radial direction, and n is the number of lines of nodes that lie in a circumferential direction. It should be noted that m and n are both integers. Therefore, a value in Fig. 5(a) the mode shown is a (0, 0)-mode, Fig. 5(b) represents a (1, 0)-mode, Fig. 5(c) represents a (0, 1)-mode and in Fig. 5(d) represents a (1, 1) mode. Furthermore, a higher-order vibrational mode can also be used, where m is 2 or more and n is 2 or more.

[0044] In the present embodiment, the Fig. The (0, 0) mode shown in Figure 5(a) is used as a principal oscillation. In other words, the piezoelectric oscillation element 13 described above is configured such that, at the lid section 15 described above, the principal oscillation is strongly excited in the (0, 0) mode. As long as there is no deviation from this configuration, there is no specific restriction on the structure of the piezoelectric oscillation element 13.

[0045] As long as the vibration in the (0, 0) mode described above can be strongly excited in the lid section 15, the piezoelectric vibration element 13 can have a structure in which one piezoelectric element is used or can have a structure in which three or more piezoelectric elements are laminated.

[0046] In the vibration device 11 of the present embodiment, the lid section 15, i.e., the translucent section, is strongly vibrated by the main vibration described above. This allows water droplets or the like, adhering to the second main surface 15b of the lid section 15, to be easily removed by atomization.

[0047] On the other hand, the cover section 15 is provided with the four excluding sections 18a to 18d described above, and the localized vibration sections, which are formed from four thin sections, are provided. Therefore, when the piezoelectric vibration element 13 is driven, the localized vibration is generated in which the entire cover section 15 does not vibrate uniformly, due to the thin sections described above. Fig. Figure 6 is a schematic top view to illustrate localized vibration. Regions indicated by alternating long and short dashed lines A1 and A2 are shown in Fig. 6. Where the excluded sections 18a to 18d project towards the outer surface section of the second main surface 15b, regions indicated by alternating long and short dashed lines B1 and B2 project conversely towards an outer surface section of the first main surface 15a. In other words, the sections where the excluded sections 18a to 18d are provided are alternately displaced to project in the thickness direction to one side and the other. The excluded sections 18a and 18b and the excluded sections 18c and 18d are displaced in opposite phases. Thus, the sections indicated by the dashed lines C1 and C2 become vibration nodes.

[0048] Since the majority of vibration segments are localized, the entire cover section 15 is not displaced uniformly during such a localized vibration. Therefore, the vibration is referred to as the localized vibration.

[0049] Fig. Figure 7 is a schematic top view to illustrate the main vibration. In this case, the entire cover section 15 is displaced uniformly.

[0050] Meanwhile, a drive circuit 25, as it is in Fig. Figure 1 shows a piezoelectric vibration element 13 connected to a drive frequency conversion circuit 26. The drive circuit 25 outputs an alternating current signal to drive the piezoelectric vibration element 13. The drive frequency conversion device 26 has a function of changing the frequency of the drive signal.

[0051] Using the drive circuit 25 and the drive frequency conversion circuit 26 described above, an alternating current signal with a predetermined frequency is applied to the piezoelectric oscillating element 13. As a result, the cover section 15 oscillates as described above. Fig. Figure 8 is a circuit diagram that illustrates the relationship between the frequency of the driving signal and the response of the vibration mode to be excited. In the diagram, E1 shows the response of the vibration in the (0, 0) mode, and E2 and E3 each show the response of the localized vibration.

[0052] Accordingly, by converting the drive frequency using the drive frequency conversion circuit, the main oscillation mode and the localized oscillation mode described above can be strongly excited.

[0053] Fig. Figure 9 is a diagram that shows a relationship between the position in the lid section oscillating in the localized vibration mode indicated by E3, as described above, and a displacement magnitude, that is, a displacement distribution. It should be noted that in Fig. 9 and Fig. 10, which are described below, the position in the cover section on the horizontal axis indicates a position in the cover section 15 along a diameter, assuming that one end is 0 (mm) in the diameter direction. The displacement amount in the steady state is assumed to be 0 (mm) and is taken as a positive value when displaced upwards and as a negative value when displaced downwards. As described by Fig. As is evident from Figure 9, the center of the lid section 15 is significantly displaced. It is noted that the lid section 15 is in a state that is in Fig. 9 is shown, and oscillates in an inverted state of the same.

[0054] On the other hand, Fig. Figure 10 is a diagram showing the relationship between the position in the lid section oscillating in the localized vibration mode indicated by E2 and a displacement magnitude. The lid section 15 oscillates between a displacement state indicated by a solid line and a displacement state indicated by a dashed line. Fig. 10 is displayed.

[0055] When water droplets adhere to the second main surface 15b of the lid section 15, the central region can be strongly displaced by oscillation in the (0, 0) mode, that is, in the main oscillation mode. Therefore, the water droplets adhering to the central region can be removed by atomization. If small water droplets adhere, they can also be desorbed and transformed into relatively large water droplets. It is also possible to remove these relatively large water droplets by atomization.

[0056] On the other hand, not all water droplets can be removed solely by oscillation in the (0, 0) mode described above. In contrast, in the Fig. 9 and Fig. The localized vibration mode shown in Figure 10 localizes the vibration, although its amplitude is smaller than that of the main vibration mode. Thus, it is possible to move adhering water droplets from the center to an outer section by oscillating in this mode. In other words, by alternately exciting the main vibration mode and the localized vibration mode, it is possible to remove water droplets adhering to the center by atomizing and coalescing the smaller water droplets and moving the water droplets that cannot be atomized to the outer section. Then, the water droplets moved to the outer section can also be removed by atomization or similar processes at that outer section.

[0057] The reason why the adhering water droplets can be moved towards the circumferential section during the localized vibration as described above is that the localized vibration section is provided as described above. However, if the localized vibration section overlaps with the center of the cover section 15, that is, the center of the translucent section, the water droplets cannot move towards the circumferential section. In other words, to achieve the movement of the water droplets towards the outer circumference, it is desirable that the localized vibration section be positioned in a location that does not overlap with the center of the cover section 15, that is, the center of the translucent section, which represents the center of the field of view of the image-generating element.

[0058] Fig. Figure 11 is a schematic top view to illustrate the localized vibration section according to a variation of the first embodiment.

[0059] In the embodiment described above, the localized vibration section formed from the thin section is provided by providing each of the excluded sections 18a to 18d with a circular planar shape. In the present invention, the planar shape of the excluded section or the thin section described above is not limited to this. As shown in Fig. As shown in Figure 11, fan-shaped excluding sections 18e to 18h may be provided and the localized vibration sections formed from the fan-shaped thin sections may be provided.

[0060] Furthermore, the number of localized vibration segments is not particularly limited. The number is not restricted to four; a different number of localized vibration segments can be provided. Preferably, the number of localized vibration segments is even. In this case, it is possible to equalize the number of localized vibration segments that vibrate in opposite phases.

[0061] More preferably, the number of localized vibration sections is two or four, and even more preferably four, as in the first embodiment. In this case, it is easy and desirable to shift two localized vibration sections and the other two localized vibration sections in opposite phases.

[0062] Additionally, the localized vibration segment preferably has a circular planar shape. In this case, the localized vibration mode is hardly dispersed. Thus, the amplitude of the localized vibration mode can be increased.

[0063] Furthermore, it is preferred that the depth of each of the excluded sections 18a to 18d and 18e to 18h, which form the localized vibration section, lies within a range of 25% or more and 75% or less of the thickness of the cover section 15, including the translucent section. If the depth is 25% or more of the thickness, the localized vibration section, which sufficiently excites the localized vibration, is generated more reliably. If the depth is 75% or less of the thickness, sufficient strength can be provided to the translucent section even if the excluded section is provided within the translucent section.

[0064] In the first embodiment, the second disc-shaped plate 18 is connected to the first disc-shaped plate 17, but the cover section 15 can be provided by a disc-shaped plate having a recessed section on one surface. For example, a recessed section in a plate-shaped translucent component can be provided by pressing.

[0065] Fig. 12 to Fig. Figure 14 shows cross-sectional front views to illustrate a second to fourth variation of the localized vibration sections.

[0066] As it is in Fig. As shown in Figure 12, the excluded sections 18a and 18b, and the excluded sections 18e and 18j, can be provided in the cover section 15 on the first main surface 15a and the second main surface 15b respectively.

[0067] As it is in Fig. As shown in Figure 13, material layers 18k and 18l, which differ from the material forming the cover section 15, may also be provided in the excluded sections 18a and 18b. Furthermore, the different material layers 18k and 18l may be connected to at least either the first main surface 15a or the second main surface 15b of the cover section 15 without providing the excluded sections 18a and 18b.

[0068] As it is in Fig. As shown in Figure 14, through-holes may also be provided in a lid section main body 15c, which is made of glass, in addition to the lid section 15. A different material sheet 18m may be laminated onto a surface of the lid section main body 15c. The other material sheet 18m is made of a material different from that of the lid section main body 15c. The through-holes are closed by this other material sheet 18m, and the excluded sections 18a and 18b are provided.

[0069] As it is in Fig. 11 to Fig. As shown in Figure 14, the structure of the localized guide section described above is not particularly restricted in the present invention, as long as the localized vibration can be generated. Furthermore, it is preferred that the localized vibration section and the remaining section of the translucent section are configured to differ from each other, at least in terms of a modulus of elasticity, density, or Poisson's ratio, so that the localized vibration can be excited with a large amplitude.

[0070] Fig. Figure 15 is a cross-sectional front view illustrating the localized vibration section of the vibration device according to a second embodiment of the present invention. A vibration device 41 according to the second embodiment comprises a first and second translucent plate 42 and 43. The first and second translucent plates 42 and 43 are made of transparent synthetic resin, glass, or the like. Cutout sections 42a and 42b are provided on an inner surface of the second translucent plate 42. With this configuration, the thin sections are provided, and the localized vibration sections are configured.

[0071] Piezoelectric vibration elements 44 and 45 are fixed to an outer surface of the second translucent plate 43. Furthermore, the first and second translucent plates 42 and 43 are connected by a support plate 46 positioned between them. The support plate 46 has a cavity 46a. Accordingly, the first and second translucent plates 42 and 43 are positioned opposite each other, with the cavity 46a located between them.

[0072] In the present embodiment, the center of each of the first and second translucent plates 42 and 43 described above forms the translucent section. The outer circumferential edge section of both the first and second translucent plates 42 and 43 then forms part of the vibrating body, and the piezoelectric vibration elements 44 and 45 are fixed to this vibrating body section. As described above, the central section of the component on the plate can be considered the translucent section, and the outer section can be used as the vibrating body. As in the present embodiment, a so-called convex-type piezoelectric vibration element can also be used.

[0073] Fig. Figure 16 is a cross-sectional front view of the vibration device according to a third embodiment of the present invention.

[0074] In a vibration device 51, the translucent plate, which forms the translucent section, is fitted into a tip opening of a tubular main body 14A, which forms the vibration section. Here, an upper end of the tubular main body 14A has a donut-shaped section 14c that extends inwards. Excepted sections 14d and 14e are provided on an inner surface of the donut-shaped section 14c to form the localized vibration section. That is, although the translucent plate forms the translucent section, the localized vibration section described above is provided in the donut-shaped section 14c in an outer surface area of ​​the translucent section. As described above, the localized vibration section can be provided in the vibration section as long as it does not overlap with the center of the translucent section.In other words, the localized vibration section can be located in a different position than the transparent section.

[0075] Fig. Figure 17 is an expanded perspective view of the vibration device according to a fourth embodiment of the present invention. A vibration device 61 comprises a translucent plate 62 and a rectangular plate 63. An opening 63a is provided in the center of the rectangular plate 63. The translucent plate 62 and the rectangular plate 63 are connected by a rectangular, frame-shaped support body 64, which is arranged between them. The piezoelectric vibration element 65 and 66 are connected to a lower surface of the rectangular plate 63.

[0076] As it is in Fig. As shown in Figure 18, in the vibration device 61 the localized vibration section is formed by providing recessed sections 62a and 62b on a lower surface of the translucent plate 62. As described above, the vibration device according to the present invention as a whole can have a rectangular plate shape, and the recessed section for forming the localized vibration section can also have any shape, such as a rectangle or the like.

[0077] Fig. Figure 19 is a perspective view illustrating a fifth variation of the localized vibration section of the vibration device according to the first embodiment. In the fifth variation, which is shown in Fig. As shown in Figure 19, a single excluded section 71a is provided on the first main surface 15a of the cover section 15. As described above, a single localized vibration section can be formed by providing the single excluded section 71a.

[0078] Fig. Figure 20 is a top view illustrating a sixth variation of the localized vibration section of the vibration device according to the first embodiment. Here, a pair of recessed sections 81a and 81b are provided on the first main surface 15a of the cover section 15. The recessed section 81a has a shape in which an arc of an inner second circle with a different radius is connected at both ends. The central angle of this arc is set to approximately 180°. In this case, when the cover section 15 vibrates, a section on the side of the recessed section 81a, indicated by a dashed line, and a section on the side of the recessed section 81b, indicated by an alternating long and short dashed line, become sections that are set into vibration in opposite phases.Accordingly, the water droplets or the like can be efficiently moved from the center of the lid section 15 to the outer section.

[0079] Fig. Figure 21 is a top view illustrating a seventh variation of the localized vibration section of the vibration device according to the first embodiment. As shown in Fig. As shown in Figure 21, four excluded sections 91a to 91d may be provided on the first main surface 15a of the cover section 15. The excluded sections 91a and 91b correspond to shapes formed by dividing the Fig. 20 are obtained from the exempted section 81a shown. Exempted sections 91c and 91d correspond to forms obtained by parts of exempted section 81b, which is set out in Fig.Figure 20 is shown in the center. In this case, the excluded section 91a and the excluded section 91d are opposite each other, with the center of the cover section 15 positioned between them. The excluded section 91b and the excluded section 91c are opposite each other, with the center of the cover section 15 positioned between them. When the cover section 15 oscillates, a section of the excluded sections 91b and 91c, indicated by a dashed line, and a section of the excluded sections 91a and 91d, enclosed by a line with alternating long and short dashes, are set into strong oscillation in opposite phases. Therefore, the water droplets adhering to the center of the cover section 15 can be efficiently moved to the outer circumferential side of the cover section 15. Reference symbol list 1 Image generating device 2 Image generation element 3a - 3c lens 4 lens housing bodies 5, 16 carrying section 6 Base plate 11, 41, 51, 61 Vibration device 12 vibrating bodies 13, 65, 66 piezoelectric vibration element 14, 14a tubular main body 14c donut-shaped section 15 Cover section 15a, 15b first and second main surface 15c Cover section main body 16a, 14d, 14e, 18a to 18j, 42a, 42b, 62a, 62b, 71a, 81a, 81b, 91a to 91d (excluded section) 17 first disc-shaped plate 18 second disc-shaped plate 18k, 18l material layer 18m other material panel 21 piezoelectric element 22 metal plate 23, 24 electrode 25 Drive circuit 26 Drive frequency conversion circuit 42, 43 first and second translucent plate 44, 45 piezoelectric vibration element 46 Support plate 46a Cavity 47 tubular supporting element 48 camera 62 translucent panels 63 rectangular plates 63a Opening 64 carrying bodies

Claims

[1] A vibration device having the following features: a vibrating body with a translucent section having a first and second principal surface opposite each other, and a vibrating section continuous with the translucent section and vibrating together with the translucent section with a principal vibration; and a piezoelectric vibration element that is fixed to the vibration section; wherein a plurality of localized vibration sections, which generate a localized vibration that differs from the main vibration, are provided at a position that does not overlap with a center of the translucent section. [2] The vibration device according to claim 1, wherein the piezoelectric vibration element is fixed to the vibration section of the vibration body, so that the main vibration and the localized vibration are excited. [3] The vibration device according to claim 1 or 2, wherein the localized vibration section is provided in the translucent section and differs from the remaining section of the translucent section at least in either a modulus of elasticity, a density and a Poisson number. [4] The vibration device according to claim 1 or 2, wherein the localized vibration section is provided in the translucent section and is a thin section having a thickness less than the thickness of the remaining section of the translucent section. [5] The vibration device according to claim 4, wherein at least either the first or the second main surface of the translucent section in the thin section is provided with an excluding section. [6] The vibration device according to claim 5, wherein the excluded section is provided on the first main surface. [7] The vibration device according to claim 1 or 2, wherein the localized vibration section comprises a section made of a material that differs from a material of the remaining section of the translucent section. [8] The vibration device according to claim 1 or 2, wherein the localized vibration section is provided in the vibration section. [9] The vibration device according to any one of claims 1 to 8, wherein a planar shape of the localized vibration section is circular. [10] The vibration device according to any one of claims 1 to 9, wherein the number of localized vibration segments is an even number. [11] The vibration device according to any one of claims 1 to 10, wherein the vibration body comprises a tubular main body and a lid section which closes an opening of the tubular main body, and the light-transmitting section is provided in the lid section. [12] The vibration device according to any one of claims 1 to 10, wherein the vibration body has a rectangular plate shape. [13] The vibration device according to one of claims 1 to 12, which further comprises a drive circuit for driving the piezoelectric vibration element. [14] The vibration device according to claim 13, which further comprises a drive frequency changing device for changing a frequency of a drive signal of the piezoelectric vibration element. [15] An image-generating device having the following features: the vibration device according to any one of claims 1 to 14; and an image-generating element provided to be positioned opposite the first main surface for recording an outside of the second main surface of the vibrating body of the vibrating device. [16] The image generation device according to claim 15, wherein the localized vibration section is positioned outside a field of view of the image generation element.

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