JP2017170303A - Droplet removal device, imaging device having droplet removal device, control method of droplet removal device, and control program of droplet removal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a droplet removal device having a function for removing surely and efficiently a droplet or the like adhering to a light flux passing region of a dome type droplet prevention cover.SOLUTION: A droplet removal device includes an optical element 111 including a curved surface-shaped dome part 123 having a light flux passing region allowing passage of a light flux for forming an optical image, an excitation member 120 provided on an installation part formed of a surface having a curvature of 0 at least in one direction, connecting to a curved surface forming the dome part of the optical element, for generating bending vibration in the dome part of the optical element, and a vibration control device 401 for controlling the excitation member.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a droplet removing device having a function of removing droplets and the like adhering to a light beam passage region through which a light beam for forming an optical image passes, an image device having the droplet removing device, and the droplets The present invention relates to a control method for an ejecting apparatus and a control program for the droplet ejecting apparatus.

  Conventionally, an optical image formed by an imaging optical system is sequentially subjected to photoelectric conversion using an imaging device or the like, and an image signal acquired thereby is transmitted to an image display device and sequentially displayed using the image display device. In general, an image apparatus configured to be able to be used has been put into practical use.

  Also, in recent years, this type of image device is fixedly installed outdoors or indoors, so that a so-called fixed point observation or monitoring or security camera configured to be able to constantly monitor the state of an area or space to be imaged. Various systems are widely used.

  Furthermore, by fixing the same image device to a predetermined part of the vehicle or the like, for example, an area that is a blind spot from the driver's seat, such as a vehicle rear region or a side region, can be displayed on the image display device, or the surrounding area during vehicle operation By continuously capturing an image of an area, an image of a predetermined time before and after a predetermined time (for example, a time when an abnormal shock is received (so-called accident occurrence time)) is recorded on a recording medium or acquired Various so-called in-vehicle camera systems and the like for use in vehicle operation control such as a lane keeping function and an emergency stop function using a field-of-view image and the like are widely used.

  Since image devices used in these systems are often installed outdoors, for example, when it rains, for example, the optical system closest to the front surface of the imaging optical system or a protective glass disposed on the front side thereof There is a possibility that rainwater or the like adheres as droplets or cloudiness (hereinafter abbreviated as droplets or the like) to a region through which a light beam for forming an image passes. In this way, when a situation such as droplets adhering to an optical system or the like occurs, the above-mentioned droplets or the like appear as a blurred image in the image acquired at that time, and a clear image cannot be acquired. There is. Therefore, it is desirable that the adhesion of droplets or the like to such an optical system is suppressed as much as possible, and the adhered droplets or the like are quickly removed.

  However, this type of conventional image device is generally installed in a place where a user (user) cannot easily reach. Therefore, in such an image apparatus, there is a demand for a device for quickly removing droplets and the like adhering to the light beam passage region on the outer surface on the front side such as an imaging optical system and protective glass.

  For example, in a vehicle or the like, generally, a mirror or the like for confirming a rear view (so-called rearview mirror) is installed outside the vehicle. Even in this type of mirror or the like, when a droplet or the like adheres to the mirror surface, it becomes a factor that hinders the formed image. Therefore, a configuration for removing droplets and the like adhering to the mirror surface is proposed by, for example, Japanese Patent Laid-Open No. 3-114962.

  In the drop eliminator disclosed in the above Japanese Patent Application Laid-Open No. 3-114962, in a vehicle mirror, an ultrasonic vibrator and a surface heating means are arranged in a space on the back side of the mirror, and the mirror is ultrasonically vibrated from the back side. In addition, the liquid droplets and the like adhering to the mirror surface are excluded by heating and heating.

  Further, as a droplet removing device applied to an in-vehicle image device, various types of devices are disclosed in, for example, Japanese Patent Laid-Open Nos. 2006-279560 and 2015-207020.

  An in-vehicle image device having a droplet removing device disclosed in Japanese Patent Application Laid-Open No. 2006-279560 is provided so as to cover the front surface of an imaging optical system and swings around a swing axis with respect to a housing. A spherical cover member that is movably supported, a wiper member that abuts against the cover member, and a weight provided at an end of the cover member in a direction perpendicular to the swing axis. ing. Then, the spherical cover member is swung with respect to the housing by the inertial force of the weight due to the acceleration change of the housing, and the cover is swung with respect to the wiper member. Thereby, the liquid droplets and the like adhering to the cover member are removed by the wiper member.

  An in-vehicle image device having a droplet removing device disclosed in Japanese Patent Application Laid-Open No. 2015-207020 and the like includes a guide path for allowing water droplets adhering to the upper surface of the housing to flow down from the upper side of the imaging optical system. It is formed on the upper surface of the body.

Japanese Patent Laid-Open No. 3-114962 JP 2006-279560 A JP-A-2015-207020

  However, the liquid drop removing device disclosed in Japanese Patent Laid-Open No. 3-114962 only discloses an example applied to a vehicle mirror. In the case of a vehicle mirror, various constituent members for removing droplets attached to the mirror surface can use the space on the mirror back side. Further, the mirror is formed in a plane, and when the mirror surface is placed in a direction close to a direction orthogonal to gravity, the shape is not suitable for removing the droplet. However, in the above-described imaging apparatus having the above-described configuration, the optical member to which droplets or the like adhere must pass a light beam for forming an optical image, and the installation direction is also a direction orthogonal to gravity. There is. Therefore, there is a problem that the configuration disclosed in Japanese Patent Laid-Open No. 3-114962 cannot be applied to an image apparatus as it is.

In addition, in a vehicle-mounted image apparatus having a droplet removing device disclosed in Japanese Unexamined Patent Publication No. 2006-279560 and the like, a wiper member is used as a member for removing droplets and the like. Since the wiper member intermittently crosses the light beam passage region through which the light beam for forming an optical image passes, moments that temporarily and periodically block the field of view are generated, and thus continuous imaging is always performed. There is a problem that it becomes an obstacle to perform. Further, since the liquid wiper member is slid on the cover member to remove droplets and the like, wear occurs between them. Therefore, there is also a problem that deterioration over time occurs during long-term use, and the droplet removing function is lowered. And it is also conceivable that a foreign substance such as a solid substance is sandwiched between the wiper member and the cover member. In this case, if the wiper member slides on the surface of the cover member with the foreign matter sandwiched in between, the surface of the cover member may be damaged. If the cover member is scratched in the light flux passage region, the captured image is deteriorated.

  On the other hand, the in-vehicle image device having the droplet removing device disclosed in the above Japanese Patent Application Laid-Open No. 2015-207020 and the like is intended to flush the droplets attached to the front surface of the housing, This is not a configuration for positively removing liquid droplets or the like adhering to the light beam passage region in the cover member or the like on the front side of the imaging optical system.

  On the other hand, in a conventional in-vehicle camera system, a surveillance or security camera system, and the like, there is a tendency that a wide-field optical system capable of obtaining a wide angle of view is applied in order to ensure a wide observation field of view. This type of wide-field optical system has a configuration in which the foremost optical lens of the imaging optical system protrudes forward, or the aperture on the front side of the holding frame that holds the imaging optical system in order to ensure a wide field of view. There is a tendency to be in a form to ensure a large. Therefore, in the image device to which such a wide-field optical system is applied, when considering miniaturization of the device, for example, a cover member having a shape that can cover the front surface of the imaging optical system, for example, a curved surface shape (dome shape) is applied. It is considered.

  However, when a curved (dome-shaped) cover member is used, it is difficult to perform uniform removal even if, for example, a wiper member is used to remove droplets adhering to the cover member. is there.

  The present invention has been made in view of the above-described points, and an object of the present invention is to provide a droplet removing device including a drip-proof cover member having a curved surface (dome shape) on the front side of an imaging optical system. A droplet ejecting device having a function of reliably and efficiently removing droplets and the like adhering to a light beam passage region of an optical system that transmits a light beam for forming an optical image, and the droplet ejecting device An image device is provided.

  In order to achieve the above object, a liquid droplet ejection apparatus according to an aspect of the present invention includes an optical element having a light beam passage region through which a light beam for forming an optical image passes, and having a curved dome portion. An excitation member connected to a curved surface forming the dome portion of the optical element and provided in an installation portion formed of a surface having at least one curvature in one direction, and generates bending vibration in the dome portion of the optical element And a vibration control device for controlling the vibration member.

  An image device according to one embodiment of the present invention includes a lens unit including an imaging optical system that forms an optical image, a body unit including an imaging element, and the droplet removing device.

  According to the method for controlling a droplet removing device of one embodiment of the present invention, a vibration operation is performed to generate bending vibration in the dome portion of the optical element.

  A control program for a droplet evacuation apparatus according to an aspect of the present invention causes a computer to execute a method for controlling a droplet evacuation apparatus including an excitation step for generating bending vibration in a dome portion of an optical element.

  According to the present invention, in a liquid droplet ejecting apparatus provided with a curved (dome-shaped) drip-proof cover member on the front side of an imaging optical system, the light beam passage of the optical system that allows the light beam for forming an optical image to pass therethrough. Droplet removing device having a function of reliably and efficiently removing droplets adhering to a region, an image device having the droplet removing device, a method for controlling the droplet removing device, and the droplet removing device A control program can be provided.

1 is a schematic perspective view showing an external appearance of an image apparatus (camera) to which a liquid droplet ejecting apparatus according to an embodiment of the present invention is applied. The block block diagram which shows the internal structure of the imaging device of FIG. The front view which removes and shows a cover member from the droplet removal apparatus of this embodiment Sectional drawing which follows the [4]-[4] line of FIG. 3 of the droplet removal apparatus of this embodiment. The principal part disassembled schematic perspective view which shows the basic structural member of the droplet removal apparatus of this embodiment in a simplified manner The top view which shows the signal electrode surface of a piezoelectric element by taking out and showing a piezoelectric element and a flexible printed circuit board connected to the piezoelectric element in the liquid droplet ejecting apparatus of this embodiment The figure which shows notionally the effect | action of the droplet removal apparatus of this embodiment. FIG. 8 is a diagram schematically showing vibration generated on the surface of the dome portion shown in FIG. 7 and showing only the outer surface of the dome portion of FIG. 7. FIG. 8 is a diagram schematically illustrating vibration generated on the surface of the dome portion illustrated in FIG. 7, in which the vibration amplitude illustrated in FIG. FIG. 7 is a diagram schematically showing the resonance vibration of bending generated when a predetermined frequency higher than the frequency of the voltage applied to the piezoelectric element to generate the vibration of the dome portion shown in FIG. 7 is applied to the piezoelectric element. The circuit diagram which shows roughly the structure of the piezoelectric element control part in the droplet removal apparatus of this embodiment The time chart which shows each signal form output from each structural member in the piezoelectric element control part of FIG. Flowchart of main control in the droplet ejecting apparatus of this embodiment The flowchart which shows the subroutine of the vibration operation processing contained in FIG. The flowchart which shows the modification of the vibration operation process in this embodiment The principal part disassembled perspective view which shows one modification about the dust-proof cover and piezoelectric element (vibrating body which consists of) in the droplet removal apparatus of this embodiment. The top view which shows the other modification about the dustproof cover and piezoelectric element (vibrating body which consists of) in the droplet removal apparatus of this embodiment, and shows the signal electrode surface of a piezoelectric element FIG. 17 is a diagram conceptually showing a polarization configuration of a piezoelectric element in the modification of FIG. FIG. 17 is a diagram conceptually showing vibration amplitude generated at a certain latitude when the dome is viewed from the optical axis direction in the modification of FIG. FIG. 19 is a diagram showing the horizontal axis as a circumferential angle φ with respect to vibration at a predetermined latitude shown in FIG.

  The present invention will be described below with reference to the illustrated embodiments. Each drawing used in the following description is schematically shown. In order to show each component in a size that can be recognized on the drawing, the dimensional relationship and scale of each member are different for each component. May be shown. Accordingly, the present invention is limited only to the illustrated embodiments with respect to the quantity of components, the shape of the components, the size ratio of the components, the relative positional relationship of the components, and the like described in the drawings. It is not something.

  In each embodiment of the present invention, an optical image formed by an imaging optical system is converted into a CCD (Charge Coupled Device) image sensor or a CMOS (Complementary Metal Oxide Semiconductor) type image, for example. A photoelectric conversion device such as a sensor (hereinafter referred to as an imaging device) is used for sequential photoelectric conversion, and an image signal obtained thereby is converted into image data of a predetermined form (for example, digital image data representing a still image or a moving image). The converted image data is sequentially transmitted to an image display device such as a liquid crystal display (LCD) or an organic electro-luminescence (OEL) display, and the image display device. The image apparatus of the form comprised so that it can be displayed as an image using is shown. This image apparatus may further include a storage device including a storage medium for storing image data. In this case, it also has a function of reproducing and displaying an image based on the digital image data stored in the storage medium using the image display device.

  In each embodiment, the optical axis of the imaging optical system in the optical device is represented by reference symbol O. In the direction along the optical axis O, the side of the subject (imaging target) facing the front surface of the optical device is referred to as the front. In addition, the side where the light receiving surface (imaging plane) of the imaging element in the body of the optical device is located is referred to as the rear.

  Further, an axis parallel to the optical axis O of the imaging optical system is defined as a Z-axis, and the left-right direction (horizontal direction) toward the front surface of the optical device among the two axes orthogonal to the Z-axis and orthogonal to each other is X Similarly, an XYZ coordinate system is defined in which the vertical axis (vertical direction) is the Y axis. In this case, the origin of the coordinate system is at the center of the imaging surface (imaging plane) of the imaging device, and is the point where the imaging surface and the optical axis O of the imaging optical system intersect. In this coordinate system, the XY plane is a surface coinciding with the imaging surface.

[One Embodiment]
1 and 2 are views showing an image device (camera) to which a droplet removing device according to an embodiment of the present invention is applied. Of these, FIG. 1 is a schematic perspective view showing the appearance. FIG. 2 is a block diagram showing the internal configuration.

  3 to 6 are views showing the droplet removing device of the present embodiment. 3 is a front view when the cover 410 is removed from the droplet ejecting apparatus, and FIG. 4 is a cross-sectional view taken along the line [4]-[4] in FIG. FIG. 5 is an exploded schematic perspective view of the main part, showing simplified basic components of the droplet removing apparatus of the present embodiment. FIG. 6 is a plan view showing the signal electrode surface of the piezoelectric element by taking out the piezoelectric element and the flexible printed circuit board connected to the piezoelectric element from the droplet ejecting apparatus of this embodiment.

  As shown in FIGS. 1 and 2, the camera 1 that is the image device of the present embodiment includes a lens unit 100, a body unit 200, and an interface 300 (not shown in FIG. 1, see FIG. 2. (Hereinafter abbreviated as “I / F”), and the droplet removing device 400 of the present embodiment.

  Here, the lens unit 100 is connected to the body unit 200 by a bayonet connection of a mount unit (not shown) provided on the rear end surface to a mount unit (not shown) provided on the front surface of the body unit 200. The lens barrel is configured to be detachable and has an imaging optical system inside, but is not limited to this example. For example, the lens unit 100 may be fixedly arranged with respect to the body unit 200.

  The lens unit 100 includes an imaging optical system (front lens 118, focus lens 101, variable magnification lens 102, and the like), a diaphragm 103, a driver 104 for the focus lens 101, a driver 105 for the variable power lens 102, and a diaphragm 103. And a microcomputer (Lucom) 107 as a sub-control unit on the lens unit 100 side, a flash memory 108 for the lens unit 100, and a droplet removing device 400. .

  As described above, in the camera 1 that is the image device of the present embodiment, an example in which the lens unit 100 includes the droplet removing device 400 of the present embodiment is shown. However, the present invention is limited to this embodiment. There is nothing. As another form example, for example, a configuration in which the droplet removing device 400 and the lens unit 100 are formed separately and the droplet removing device 400 can be mounted on the front side (tip portion) of the lens unit 100. It is good. In this case, both the droplet removing device 400 and the lens unit 100 may be integrally configured, or the droplet removing device 400 may be configured to be detachable with respect to the tip portion of the lens unit 100. . In other words, the droplet removing device 400 of the present embodiment only needs to be arranged in front of the imaging optical system in the lens unit 100.

  An imaging optical system in the lens unit 100 is configured by a plurality of optical systems such as the front lens 118, the focus lens 101, and the variable magnification lens 102, and the diaphragm 103. This imaging optical system is a component that transmits incident light from a subject (imaging target) and forms an optical image of the subject (imaging target) on an imaging surface of an imaging element 202 described later.

  Among these, the focus lens 101 mainly includes an optical lens group that contributes to focus adjustment. The variable power lens 102 mainly includes an optical lens group that contributes to a variable power operation (zoom operation). The diaphragm 103 is a unit that constitutes a light amount adjustment mechanism for adjusting the light amount of the light beam transmitted through the imaging optical system. The front lens 118 is an optical lens disposed on the forefront side of the imaging optical system. The front lens 118 is an optical lens formed so as to protrude forward in the direction along the optical axis O, for example. The imaging optical system having the front lens 118 having such a configuration is often found in, for example, a wide-field optical system configured to obtain a wide angle of view. That is, it is assumed that a wide-field optical system is applied as the imaging optical system applied to the camera 1 that is the image apparatus of the present embodiment.

  The focus lens 101 is driven by a driver 104. The variable magnification lens 102 is driven by a driver 105. The diaphragm 103 is driven by a driver 106. These drivers 104, 105, and 106 are configured to include a drive mechanism, a drive motor, and the like, and are controlled by the microcomputer 107 on the lens unit 100 side under the control of the microcomputer 214 that is a main control unit on the body unit 200 side described later. Drive controlled.

  In the above-described example, the imaging optical system in the camera 1 has the variable focal length variable magnification lens 102 and the focus lens 101 that can adjust the focus. However, the present invention is limited to this example. There is no. For example, a single focus lens (single focus optical system) with a fixed focal length may be used. In this case, the variable power lens 102 and its driver 105 are unnecessary. Alternatively, the focus lens 101 may be a fixed focus optical system that is non-movable (fixed). In this case, the focus lens 101 and its driver 104 are unnecessary. A microcomputer (Lucom) 107 is a sub-control unit that controls the lens unit 100 side. The microcomputer 107 is electrically connected to a microcomputer (Bucom) 214 on the body part 200 side, which will be described later, via an interface (I / F) 300 so that they can communicate with each other.

  The electrical connection between the microcomputer 107 and the microcomputer 214 is established in a state where the lens unit 100 is attached to the body unit 200 (in the case of a lens detachable type). The microcomputer 107 is configured to operate as the camera 1 while cooperating with the microcomputer 214 in a dependent manner. In the case where the lens unit 100 and the body unit 200 are integrated cameras, the microcomputers 107 and 214 may be configured as one microcomputer.

  The flash memory 108 is a memory unit that stores various data on the lens unit 100 side. Various data stored in the flash memory 108 are read out at a predetermined timing by the microcomputer 214 on the body unit 200 side and used for various controls in the camera 1. In addition, the flash memory 108 may store control data and a control program for the droplet removing device 400.

  The droplet removing device 400 includes a drip-proof cover 111 (optical element) having two shapes (installation portion) of a curved surface (dome-shaped) dome portion and a flat plate flange and a cylinder connected to the curved surface constituting the dome portion. ), A vibration control device 401 including a vibration member (piezoelectric element 120; described later) and controlling the vibration member, a heating control device 402 including a heating member (heater 130; described later) and controlling the heating member, It is mainly configured by a cover member 410 (not shown in FIG. 2) or the like. The droplet removing device 400 is a constituent unit for removing droplets and the like (see reference numeral 500) attached to the outer surface of the drip-proof cover 111 as shown in FIG.

  Here, as a situation where droplets or the like adhere to the outer surface of the drip-proof cover 111, for example, when the camera 1 is installed outdoors, the surrounding environment may be due to weather conditions such as rain or storm. Conceivable. As another situation, there may be a case in which one of the device internal temperature and the external temperature on the camera 1 side is a low temperature, the other is a high temperature and the humidity is high. Under such circumstances, the outer surface temperature of the drip-proof cover 111 and the outside air temperature on the outer surface side of the drip-proof cover 111 or the temperature of the inner surface and inner surface side of the drip-proof cover 111 (inner air temperature). Due to the temperature difference therebetween, droplets and fogging occur on the outer surface side or inner surface side of the drip-proof cover 111. In this case, the cloudiness generated in the drip-proof cover 111 or the like is a fine state of the droplets. Accordingly, in the following description, it is simply abbreviated as a droplet or the like.

  In the droplet removing device 400, the drip-proof cover 111 is formed in accordance with the outer shape of the front lens 118 of the imaging optical system and is formed to protrude forward so as to cover the front side of the front lens 118. It is an optical element formed by using a curved glass (dome-shaped) transparent glass or resin-made transparent member.

  As shown in FIG. 4 and the like, the drip-proof cover 111 has a dome portion 123, a cylindrical portion 122, and a flange portion 124.

  The dome 123 is a part constituting the main part of the drip-proof cover 111, has a light flux passage region 170, and is formed in a curved surface as a whole. The dome portion 123 is formed in a size that can ensure a slightly larger region than the light beam passage region 170 (see FIG. 3) through which the light beam from the subject transmitted through the imaging optical system in the lens unit 100 of the camera 1 passes. The dome 123 is formed so as to obtain a wide field of view with a viewing angle toward the front surface of approximately 180 degrees. Then, at least a part of the front lens 118 of the imaging optical system is arranged in the inner region of the dome portion 123.

  The cylindrical part 122 (installation part) is a structural part that is formed in a form in which the base end of the dome part 123 extends in a cylindrical shape and has an opening directed rearward. Although details will be described later, a heater 130 is disposed at a predetermined portion on the inner surface side of the cylindrical portion 122.

  The flange portion 124 (installation portion) extends in the circumferential direction of the cylindrical portion 122 from the portion toward the outer peripheral side in the vicinity of the connection portion between the base end of the dome portion 123 and the cylindrical portion 122. And has an annular surface orthogonal to the optical axis O. A plate-like piezoelectric element 120 is disposed on the back side of the flange portion 124 as will be described later.

  Although the details will be described later, the drip-proof cover 111 supports the components of the vibration control device 401 and the heating control device 402, protects the front side of the imaging optical system, and prevents liquid droplets from entering from the outside. The light beam from the subject (imaging object) can be transmitted while being suppressed. Therefore, the drip-proof cover 111 is arranged on the optical axis O of the imaging optical system, and is arranged so that the optical axis O passes through the apex portion of the curved surface shape (dome) of the drip-proof cover 111.

  The vibration control device 401 is mainly configured by the piezoelectric element control unit 109 and the piezoelectric element 120 (vibration member) (see FIG. 1 and the like).

  The piezoelectric element 120 is a vibration member for generating vibrations in the drip-proof cover 111 (optical element). The piezoelectric element 120 is formed on the inner surface side of a predetermined position of the drip-proof cover 111 (a flange portion 124 described later; see FIG. 3 and the like) in an annular shape and having a plate thickness over the entire circumference. It is bonded and fixed along the inner surface of the portion 124.

  The piezoelectric element 120 is formed of a piezoelectric material such as an annular plate-shaped piezoelectric ceramic, and has two electrodes (171, 172; FIG. 5 to be described later) for applying a voltage in the thickness direction of the piezoelectric element 120. (See FIG. 6). In this case, as shown in FIG. 5, one electrode 172 on one side (adhesion surface side) is routed on one end surface of the piezoelectric element 120, and the other surface (surface on the non-adhesion side) via the side surface 172a. An electrode is formed in part. The two electrodes (171, 172) are electrically connected to the flexible printed circuit board 121. Although not shown, the flexible printed circuit board 121 extends to the piezoelectric element control unit 109 (see FIG. 1) and is electrically connected thereto.

  The piezoelectric element 120 is bonded and fixed to one surface of the drip-proof cover 111 (the back surface of the flange portion 124) as described above.

  With such a configuration, when the frequency voltage from the piezoelectric element control unit 109 is applied to the piezoelectric element 120 in the thickness direction, the piezoelectric element 120 is directed in a predetermined direction, that is, in the radial direction of the annular shape. Stretching vibration occurs. As will be described later, the vibration of the piezoelectric element 120 has a form as shown in FIGS. 7 to 10 with respect to the dome portion 123 of the drip-proof cover 111, that is, a concentric vibration node of the optical axis O (no vibration amplitude). It is configured to generate a bending vibration having a position).

  The piezoelectric element control unit 109 is a drive control unit for controlling the piezoelectric element 120 (vibration member) to generate a predetermined vibration. The piezoelectric element control unit 109 is a circuit unit that performs control to cause the drip-proof cover 111 to vibrate by causing the piezoelectric element 120 to vibrate at a predetermined frequency determined by the size and material of the drip-proof cover 111. By performing such control, when the drip-proof cover 111 vibrates at a predetermined frequency, droplets 500 (see FIG. 1) adhering to the outer surface of the drip-proof cover 111 are miniaturized and removed. Can be done. Furthermore, the drip-proof cover 111 is configured to vibrate so that dust and the like attached to the outer surface of the drip-proof cover 111 can also be removed.

  The heating control device 402 is mainly configured by a heating control unit 110 and a heater 130 (heating member) (see FIG. 1 and the like).

  The heater 130 is a heating member for heating the drip-proof cover 111 (optical element). The heater 130 is formed of a plate-shaped electric resistance material formed in a substantially arc shape, and, for example, on the inner surface side of the cylindrical portion 122 of the drip-proof cover 111, along the inner periphery of the lower end portion in the Y direction as shown in FIG. Thus, it is bonded and fixed with a highly heat conductive adhesive or a pressure sensitive adhesive sheet. As shown in FIG. 5, the heater 130 has a flexible printed board 131 extending at one end in the same manner as the piezoelectric element 120. And although illustration is abbreviate | omitted, the said heater 130 is electrically connected via the flexible printed circuit board 131 to the heating control part 110 (refer FIG. 1). The inner peripheral surface of the cylindrical portion to which the heater 130 is fixed has zero curvature in one direction (Y direction), so the flexible heater 130 can be fixed to the inner peripheral surface without difficulty. The inner circumferential surface of the cylindrical portion may be a conical surface. In this case, the direction of zero curvature (the direction of the generatrix of the cone) exists infinitely, but a flexible plate heater 130 is provided on the conical surface. Can be fixed without difficulty. Furthermore, if the inner peripheral surface of the cylindrical portion is a surface shape that becomes a flat surface when a surface such as a polygonal column surface, a polygonal cone surface, an elliptical cylinder surface, or an elliptical cone surface having a direction of curvature 0 is developed, it is flexible. The plate heater 130 can be fixed without difficulty. If the heater 130 is not in close contact with the fixing surface (inner peripheral surface) of the cylindrical portion, heat cannot be efficiently transmitted to the drip-proof cover 111, and the heater 130 can be easily fixed to the fixing surface (inner peripheral surface) of the cylindrical portion. Otherwise, the adhesion is deteriorated due to vibration of the drip-proof cover 111 or overheating of the heater 130, and problems such as peeling off occur.

  The heater 130 is bonded and fixed to one surface (inner surface) of the cylindrical portion 122 of the drip-proof cover 111 as described above. In this case, the heater 130 (heating member) is disposed in a lower region closer to the ground in the direction of gravity than the position where the piezoelectric element 120 (vibration member) is disposed. Of course, the shape of the heater 130 is not limited to the above example.

  With such a configuration, the heater 130 functions as a heating member configured to generate heat when the electric signal current from the heating control unit 110 flows and to heat the drip-proof cover 111.

  The electrical signal applied to the heater 130 may be direct current or alternating current, and generates heat according to the magnitude of the current. Further, in order to prevent the drip-proof cover 111 from overheating and becoming a high temperature, a temperature detection element (not shown) such as a thermistor is attached to the drip-proof cover 111 and the temperature signal of the drip-proof cover 111 is sent to the heating control unit 110. It is good also as a structure which feeds back to and controls the heat_generation | fever of the heater 130. FIG. In this case, the temperature detection element is preferably disposed in the vicinity of the heater 130.

  Furthermore, the heater 130 is configured to be bonded and fixed to the drip-proof cover 111. In this case, as described later, the drip-proof cover 111 is fixed along the nodal portion of the resonance vibration of the drip-proof cover 111. It is comprised so that the vibration of the dome part 123 of the cover 111 may not be inhibited (details will be described later; see FIGS. 7 to 10).

  In addition, the heat generated from the heater 130 transfers heat to the material that the heater 130 is in contact with, but the second inner space 159 that contacts the heater 130 in a large area (see FIG. 4; the inner space of the cylindrical portion 122 of the drip-proof cover 111). The heat conductivity of a gas such as air, which will be described later in detail, is as low as 0.02 W / (m · K), and most of the heat generated from the heater 130 is transmitted to the drip-proof cover 111. Incidentally, when the drip-proof cover 111 is made of general glass, the thermal conductivity is 0.8 W / (m · K), which is a numerical value larger by one digit or more than air. Therefore, the heat transmitted to the drip-proof cover 111 is also transmitted to the gas in contact with the drip-proof cover 111 and a drip-proof seal 150 (holding member) and a dust-proof seal 160 described later. If the material such as the dust-proof seal 160 is made of, for example, silicone rubber, the thermal conductivity is 0.2 W / (m · K), which is larger than air, but lower than the drip-proof cover 111, and thus the drip-proof seal. 150 (holding member), the heat transmitted from the dust-proof seal 160 to the drip-proof cover 111 does not escape, and the drip-proof cover 111 can be efficiently heated. Therefore, it is desirable that the thermal conductivity of the drip-proof cover 111 (optical element) is set larger than the thermal conductivity of the drip-proof seal (holding member) and the dust-proof seal 160.

  The heating control unit 110 causes the heater 130 to generate heat by flowing an electric signal current to the heater 130 (heating member), and can always maintain an appropriate temperature (for example, about 60 to 80 degrees Celsius). This is a drive control unit for controlling the temperature of the heater 130 and heating the drip-proof cover 111 (optical element) with the heat. The configuration of the lens unit 100 is generally as described above. In addition, the further detailed structure about the structure of the droplet removal apparatus 400 is mentioned later.

  On the other hand, as shown in FIG. 2, the body unit 200 in the camera 1 of the present embodiment includes a foreign object detection unit 201, an image sensor 202, an analog processing unit 203, an analog-digital (A / D) conversion unit 204, AE processing unit 205, image processing unit 206, AF processing unit 207, image compression / decompression unit 208, LCD driver 209, LCD 210, memory interface (I / F) 211, storage medium 212, SDRAM 213, The microcomputer 214, the flash memory 215, the operation unit 216, the bus 217, and the power supply circuit 218 are mainly configured.

  Among the constituent members included in the body part 200, the imaging element 202 is provided on the optical axis O of the imaging optical system, and forms an optical image of a subject (imaging target) formed through the imaging optical system. This is a photoelectric conversion element having a function of receiving light on the image plane and performing photoelectric conversion. The image sensor 202 is electrically connected to the analog processing unit 203.

  The analog processing unit 203 is a circuit unit that receives an image signal (analog signal) output from the image sensor 202 and performs predetermined signal processing. The analog processing unit 203 is electrically connected to an analog / digital (A / D) conversion unit 204.

  The analog / digital (A / D) conversion unit 204 is a circuit unit that receives the image signal (analog signal) output from the analog processing unit 203 and converts it into a digital signal. The analog / digital (A / D) conversion unit 204 is electrically connected to the microcomputer 214 on the body unit 200 side via the bus 217.

  The internal bus 217 is a connection transmission path for electrically connecting each of the internal configuration units of the camera 1. The internal bus 217 is a signal transmission path for transmitting various control signals and image data generated from each constituent unit to a predetermined constituent unit.

  A microcomputer (Bucom) 214 on the body unit 200 side is a main control unit that controls the camera 1 in an integrated manner. The microcomputer 214 controls each constituent unit on the body part 200 side, and can control the internal constituent units of the lens part 100 in cooperation with the microcomputer 107 on the lens part 100 side as described above. It is configured.

  In the present embodiment, an example in which the microcomputer 214 as the main control circuit unit in the camera 1 is included in the body unit 200 is shown, but the present invention is not limited to this configuration. For example, in the case of an in-vehicle camera system configured with a plurality of cameras, a microcomputer 214 is provided as a single control circuit unit, and the single control circuit unit and a plurality of cameras are connected to the internal circuit. A connection transmission path equivalent to that of the bus 217 may be used, and the single control circuit unit may perform control processing by concentrating a plurality of cameras.

  The AE processing unit 205 is a circuit unit that performs automatic exposure (AE) control processing based on the digital image signal from the A / D conversion unit 204.

  The image processing unit 206 is a circuit unit for executing other necessary image processing relating to the digital image signal.

  The AF processing unit 207 is a circuit unit that performs automatic focus adjustment (AF) control processing (for example, AF processing using a contrast detection method or an image plane phase difference detection method) based on the digital image signal from the A / D conversion unit 204. is there.

  The image compression / decompression unit 208 performs predetermined compression processing based on the digital image signal from the A / D conversion unit 204 or the image processing unit 206 or the like, and stores stored image data in a storage medium 212 (described later). This is a circuit unit for reading from the file and performing a predetermined expansion process.

  The LCD 210 is an image display device having a display screen for displaying an image. As the image display device, for example, a liquid crystal display is applied. The LCD 210 is driven and controlled by an LCD driver 209.

  In the camera 1 of the present embodiment, the body part 200 includes the LCD 210 and the LCD driver 209, but the present invention is not limited to such a form. For example, the LCD 210 and the LCD driver 209 are configured separately from the body unit 200, and are configured to be able to communicate with each other bidirectionally by wired cable or wireless communication so that image data can be exchanged. May be.

  The storage medium 212 is a storage unit that stores acquired image data and the like, predetermined control parameters necessary for camera control, and the like. As the storage medium 212, for example, a semiconductor memory in the form of a memory card, and various forms of magnetic storage media such as a disk form or a tape form can be applied. The storage medium 212 is driven and controlled by a memory interface (I / F) 211.

  In the camera 1 of the present embodiment, the body unit 200 includes the storage medium 212 and the memory interface (I / F) 211. However, the present invention is not limited to this configuration. For example, the storage medium 212 and the memory interface (I / F) 211 are configured separately from the body unit 200, and the two are communicably connected via a wired cable or wireless communication so that image data can be exchanged. You may comprise so that it can perform. Furthermore, the storage medium 212 may be fixed inside the body part 200 or may be configured to be detachable from the body part 200.

  An SDRAM (Synchronous Dynamic Random Access Memory) 213 is a memory for temporarily storing image data, for example, and is used as a work area or the like when signal processing or the like based on image data is performed.

The flash memory 215 is a non-volatile memory that stores and stores in advance various control programs for operating the camera 1. As the flash memory 215, for example, an EEPROM (Electrically Erasable Programmable Read-Only Memory) or the like is applied.

  The operation unit 216 includes a plurality of operation members, operation switches, and the like that generate various instruction signals for executing settings and operations of the camera 1. The instruction signal generated by the operation unit 216 is transmitted to the microcomputer 214 and becomes a trigger signal for various control processes. Further, in the surveillance camera and the in-vehicle camera, the operation unit 216 and the camera 1 are not integrated with each other, but are separated from each other as a camera operation device, and the camera and the operation device are connected by wire or wirelessly. Is configured.

  The power supply circuit 218 is a circuit unit that receives power from a power supply source, converts the voltage into a voltage required by each circuit unit constituting the camera 1, and supplies the converted voltage. The power supply source of the camera 1 includes, for example, a primary battery such as a dry battery, a secondary battery such as a storage battery (hereinafter referred to as a battery), and a general commercial power source.

  The foreign matter detection unit 201 is a circuit unit that detects whether or not foreign matter has adhered to the surface of the drip-proof cover 111. The foreign object detection unit 201 performs foreign object detection based on a plurality of digital image signals that are acquired by, for example, the image sensor 202 and are continuously output from the A / D conversion unit 204 through various processes. Specifically, for example, foreign matter detection is performed by performing processing for comparing an image at the start of operation of the camera 1 with an image after a predetermined time has elapsed.

  Here, the foreign matter refers to an object that adheres to the surface of the drip-proof cover 111 and becomes a factor that hinders an image to be acquired, for example, a droplet or dust. When these droplets or dust adhere to the surface of the drip-proof cover 111, an area where the contrast is extremely reduced or an image of the droplet or dust should be generated in the acquired image. In addition, when the drip-proof cover 111 is cloudy, the acquired image may be in a state where the entire area or a part of the image is extremely lowered in contrast or a clear image cannot be obtained. .

  Therefore, the foreign object detection unit 201 detects such a situation by periodically comparing the acquired images.

  In the camera 1 of the present embodiment, for example, it is assumed that the camera 1 is fixed and used in a situation where a predetermined imaging range is continuously imaged for a long time. In this case, the imaging object in the image to be captured often has little change with time over time. For this reason, for example, an image acquired at the time of starting the camera 1 is recorded as a reference image, and image processing that is sequentially performed thereafter is compared with the reference image at predetermined time intervals. It can be considered as a foreign object detection process. The structure of the body part 200 is almost the above.

  The interface 300 is a connection unit that electrically connects the lens unit 100 and the body unit 200. In the present embodiment, as described above, since the lens unit 100 and the body unit 200 are configured to be detachable, the interface 300 is required, but the lens unit 100 and the body unit 200 are integrated. When the configuration is configured, the interface 300 is not particularly required, and a connection transmission path equivalent to the internal bus 217 or the like may be provided between the constituent units of the lens unit 100 and the body unit 200.

  The camera 1 is configured to include various other constituent units other than those described above. However, the constituent units (not shown) are portions not directly related to the present invention, so The detailed description is omitted because it has substantially the same configuration as a general lens unit.

  The components of the camera 1 configured as described above generally operate as follows. First, the image processing unit 206 drives and controls the image sensor 202 in accordance with a command from the microcomputer 214. The image sensor 202 sequentially captures image signals (analog) at a predetermined timing and performs photoelectric conversion. The converted image signal (analog) is subjected to predetermined processing through an analog processing unit 203 and an A / D conversion unit 204, and then converted into a video signal by the image processing unit 206, which is output to the LCD 210 and displayed. . The user (user) can visually recognize the acquired image by checking the display screen of the LCD 210.

  Further, the image data output from the A / D conversion unit 204 is temporarily stored in the SDRAM 213. The image data temporarily stored in the SDRAM 213 is converted into JPEG data (in the case of still image data) or MPEG data (in the case of moving image data) by the image compression / decompression unit 208 under the control of the microcomputer 214. Thereafter, the data is stored in the storage medium 212 via the memory I / F 211.

  In the focus adjustment control of the imaging optical system, the position of the focus lens 101 on the optical axis O is sequentially changed, and each time an image is picked up by the image pickup element 202, and the image has the highest contrast based on the acquired image data. The high position is calculated in the image processing unit 206 under the control of the microcomputer 214, and the calculation result is transmitted to the microcomputer 107 via the interface 300, and the microcomputer 107 is on the optical axis O of the focus lens 101. Perform position control. Photometry (AE processing) is also performed by well-known processing by detecting the amount of light based on the captured image.

  Next, the detailed mechanical configuration of the droplet ejecting apparatus 400 of the present embodiment will be described below mainly using FIGS.

  As described above, the droplet removing device 400 is mainly configured by the drip-proof cover 111, the vibration control device 401, the heating control device 402, and the like. The main components are a drip-proof cover 111, a piezoelectric element 120, a heater 130, and the like. These main components are fixedly supported by a support frame (base frame) 140. Here, the support frame 140 is a pedestal member provided mainly for attaching and fixing the drip-proof cover 111 (optical element).

  Further, in the droplet removing device 400 of the present embodiment, as described above and as shown in FIG. 4, the cover member 410 is disposed so as to cover the front side of the drip-proof cover 111. In FIG. 3, the cover member 410 is not shown in order to avoid complication of the drawing.

  The cover member 410 covers the outer peripheral edge of the flange portion 124 on the base end side of the drip-proof cover 111, thereby protecting the vicinity of the portion where the vibration control device 401 and the heating control device 402 are provided from the outside. doing.

  Further, the cover member 410 is formed in a substantially cylindrical shape as a whole, and an opening for allowing the imaging light beam to pass therethrough is formed in a substantially central portion. The opening is formed to have a size that can sufficiently secure the light flux passage area 170 so as to correspond to the light flux passage area 170 so that the light flux can pass through the central portion of the drip-proof cover 111. It serves to regulate the incidence of unnecessary harmful light flux. The inner surface of the cover member 410 is subjected to surface treatment, coating, flocking, or the like for suppressing internal reflection in the cover member 410 in order to prevent harmful light from being mixed into the imaging light beam. Yes. The cover member 410 is fixed to the support frame 140 so as to cover a part of the outer peripheral edge of the support frame 140.

  By providing the cover member 410, a predetermined space (a space indicated by reference numeral 169 in FIG. 4) is provided between the inner wall of the cover member 410 and the drip-proof cover 111 and the support frame 140. As shown, it is formed as shown in FIG.

  This space 169 is an external space with respect to the drip-proof cover 111. The space 169 is formed so as to be able to receive, for example, liquid droplets that fall off the surface of the drip-proof cover 111 and drop downward in the direction of gravity (Y direction).

  In a normal case, the camera 1 is, for example, in an attitude in which the optical axis O of the imaging optical system is in a horizontal state, or in a state in which the optical axis O is tilted so that the front side of the imaging optical system faces downward. It is fixed in the desired facility.

  Therefore, when the droplets and the like attached to the outer surface of the drip-proof cover 111 of the droplet removing device 400 attached to the camera 1 installed in such a normal posture are released, the drip-proof cover It is configured such that it travels down the gravitational direction (Y direction) along the outer surface of 111 and enters the space 169.

  As shown in FIG. 4, the cover member 410 has a through hole 411 in a predetermined position on the peripheral surface thereof in a region near the ground in the direction of gravity (Y direction). Therefore, as described above, the liquid droplets that enter the space 169 and accumulate in the space 169 are discharged to the outside through the through hole 411. That is, the through-hole 411 of the cover member 410 is a component that functions as a drainage port (discharge port) that discharges droplets and the like that enter the space 169 and accumulate inside.

  In the droplet removing apparatus 400 of the present embodiment, the drip-proof cover 111 is an example in which a curved glass (dome-shaped) transparent glass is applied as described above. A drip-proof seal 150 formed in an annular shape is closely fitted and disposed on the outer peripheral edge of the flange portion 124 of the drip-proof cover 111. In this state, the drip-proof seal 150 and the flange portion 124 of the drip-proof cover 111 are in close contact with each other in a watertight state. Therefore, in this state, the drip-proof seal 150 serves as a holding member that fixes and holds the drip-proof cover 111 (optical element) and also functions as a drip-proof member that suppresses intrusion of liquid droplets and the like into the inside. doing. The drip-proof seal 150 is made of a rubber material such as silicone rubber having vibration absorption and lower thermal conductivity than the drip-proof cover 111.

  Further, as shown in FIG. 3, the drip-proof seal 150 has a plurality of protruding pieces 154 protruding in a radial direction at a predetermined portion of the outer peripheral edge. The plurality of protruding pieces 154 come into contact with a plurality of positioning projections 146 provided on the support frame 140 when the drip-proof cover 111 with the drip-proof seal 150 attached is arranged on one surface side of the support frame 140. Accordingly, the outer peripheral edge portion of the drip-proof seal 150 of the drip-proof cover 111 is positioned in the XY directions. The plurality of protruding pieces 154 are provided in at least three locations at substantially equal intervals in the circumferential direction of the drip-proof cover 111. This positioning mechanism also positions the drip-proof cover 111 in the rotational direction around the optical axis O.

  As described above, the drip-proof cover 111 in a state in which the drip-proof seal 150 is fitted and arranged on the outer peripheral edge of the flange portion 124 of the drip-proof cover 111 is arranged on one plane of the support frame 140 and will be described later. It is fixed to the support frame 140 by predetermined means.

  The support frame 140 is a housing having a rectangular through-opening 145 at a substantially central portion. The through-opening 145 is an opening for allowing an incident light beam from an object (imaging target) to pass therethrough and guiding the light beam to the imaging optical system. The support frame 140 is formed of a resin molded part using a material having low thermal conductivity, such as a synthetic resin.

  As shown in FIG. 4, the drip-proof cover 111 is arranged in a state where the plane of the flange portion 124 with the drip-proof seal 150 attached to one surface side of the support frame 140 other than the through opening 145 is placed. The At this time, a drip-proof cover receiver that protrudes from one surface of the support frame 140 toward the front surface (Z direction) is provided at a portion of the opposite surface on the support frame 140 side that faces the drip-proof seal 150. A portion 141 is formed.

  With such a configuration, when the drip-proof cover 111 with the drip-proof seal 150 attached to the one surface side of the support frame 140 is disposed, the protrusion of the outer peripheral edge of the drip-proof seal 150 attached to the drip-proof cover 111 is provided. In the installation portion 154, the plurality of positioning projections 146 position in the XY direction, and the drip-proof cover receiving portion 141 supports the positioning of the drip-proof seal 150 in the Z direction.

  Furthermore, in this state, the drip-proof seal 150 of the drip-proof cover 111 is pressed by the pressing member 151 from the front surface (Z direction) side toward the drip-proof cover receiving portion 141 of the support frame 140 on the rear side. . The pressing member 151 has a Z-shaped cross section as shown in FIG. 4, for example, by bending a plate-like metal member having spring properties.

  One piece of the pressing member 151 is fastened and fixed to one surface of the support frame 140 using a screw 152. In this case, the pressing member 151 is restricted in rotation by a rotation stop protrusion 142 that protrudes from one surface of the support frame 140 toward the front surface (Z direction). On the other hand, the pressing member 151 is arranged such that the other piece on the tip side presses the pressing receiving projection 153 on the front side of the drip-proof seal 150.

  With such a configuration, the pressing member 151 presses the drip-proof seal 150 from the front side toward the support frame 140 on the rear side, whereby a watertight state is formed between the drip-proof seal 150 and the drip-proof cover receiving portion 141. It is said. As a result, the internal space (first internal space 149 and second internal space 159; which will be described later) formed by the drip-proof cover 111, the drip-proof seal 150, and the support frame 140 is in a watertight state with respect to the outside. Yes. Further, the contact portion between the drip-proof seal 150 and the drip-proof cover 111 to which the pressing force of the pressing member 151 is applied and the contact portion between the drip-proof seal 150 and the drip-proof cover receiving portion 141 inhibit vibration of the drip-proof cover 111. However, the drip-proof seal 150 is formed of a vibration-absorbing material such as rubber, and the two contact portions are formed in a portion where the vibration amplitude of the drip-proof cover 111 is almost absent. The cover 111 does not hinder the vibration of the cover 111.

  Specifically, for example, the pressing receiving projection 153 of the drip-proof seal 150 to which a pressing force is applied by the pressing member 151 and the drip-proof cover receiving portion 141 of the support frame (base frame) 140 are arranged on the outermost peripheral side. The drip-proof cover 111 is disposed along a nodal portion (not shown) of resonance bending vibration. Thereby, the drip-proof seal 150 is configured so as not to inhibit the vibration of the drip-proof cover 111.

  Here, the first internal space 149 is a space in which the piezoelectric element 120 is disposed. In other words, the piezoelectric element 120 (vibration member) has a flange portion 124 and a cylindrical portion 122 of the drip-proof cover 111 in a portion outside the light flux passage region 170 in an internal space that is blocked from the outside by the drip-proof cover 111. It is arranged in a space surrounded by one surface of the support frame 140 and the drip-proof seal 150 (holding member).

  The second internal space 159 is a space including a light flux passage area 170 through which a light flux for forming an image passes. A front lens 118 included in the lens unit 100 of the camera 1 is disposed behind the second internal space 159. Further, as shown in FIG. 4, a heater 130 is disposed on the inner surface of the cylindrical portion 124 following the inner surface of the dome portion 123 of the drip-proof cover 111 that constitutes the second internal space 159.

  Each of the flexible printed boards 121 and 131 extending from the piezoelectric element 120 and the heater 130 is led out to the rear outside of the support frame 140 (not shown in detail).

  As shown in FIGS. 5 and 6, the piezoelectric element 120 has two electrodes 171 and 172 for applying a voltage in the thickness direction (the hatched portions in FIGS. 5 and 6). reference). The back side electrode structure of the piezoelectric element 120 is as shown in FIG. That is, of the two electrodes, the electrode (reference numeral 172) on the adhesion surface side to the drip-proof cover 111 is drawn around the side surface of the piezoelectric element 120 (reference numeral 172a), and the other surface is interposed through the side electrode 172a. An electrode (reference numeral 172) is formed on a part of the (non-adhesive surface side; FIG. 6). Further, another electrode (reference numeral 171) is formed in a region other than the electrode (reference numeral 172) on the other surface (the surface shown in FIG. 6; non-adhesive surface) of the piezoelectric element 120. Here, the electrode indicated by reference numeral 172 is a ground electrode, and the electrode indicated by reference numeral 171 is a signal electrode. The piezoelectric element 120 is plate-shaped and has a flat adhesive surface, and the flange portion 124 of the drip-proof cover 111 is provided continuously over the entire periphery of the end portion of the dome portion 123, and the curvature in two directions is zero. Therefore, the piezoelectric element 120 can be joined to the flange portion 124 very easily, and vibration can be efficiently generated in the dome portion 123.

  The operation of the droplet ejecting apparatus 400 of the present embodiment configured as described above will be described below.

  FIG. 7 is a diagram conceptually showing the operation of the droplet removing device of this embodiment.

  Specifically, FIG. 7 is a diagram for explaining the basic principle when vibrations generated on the surface of the dome portion 123 of the drip-proof cover 111 and droplets and the like are removed from the outer surface of the dome portion 123 by the vibration. It is. That is, FIG. 7 shows a cross section of the vibrating body (120 + 111) in a state where the piezoelectric body 120 is attached to the drip-proof cover 111 and bonded and fixed along the XZ plane (a plane including the X axis and the Y axis). Furthermore, an outline of vibration generated when a voltage signal from the piezoelectric element control unit 109 is applied to the piezoelectric element 120 through the signal electrode 171 and the ground electrode 172 is shown. In FIG. 7, the shape indicated by the solid line indicates a natural state that is not applied to the piezoelectric element 120, and the shapes indicated by the long broken line and the short broken line are applied to the piezoelectric element 120 to expand and contract and vibration is generated. Respectively.

  In FIG. 7, an arrow V indicated on the piezoelectric element 120 indicates the polarization direction of the piezoelectric element 120. Here, when a positive voltage is applied to the signal electrode 171, the piezoelectric element 120 contracts in the direction in which the plate thickness decreases, and extends in the direction of the electrode surface (horizontal direction; the direction orthogonal to the arrow V). Then, the flange portion 124 of the drip-proof cover 111 is bent as shown in FIG. 7, and the inner and outer diameters of the annular ring are widened. In this case, the end portion of the dome portion 123 following the flange portion 124 extends in the radial direction (a direction orthogonal to the optical axis O).

  On the other hand, when a negative voltage is applied to the signal electrode 171, the piezoelectric element 120 expands in the direction of increasing the plate thickness and contracts in the direction of the electrode surface. Then, the flange portion 124 of the drip-proof cover 111 is bent as shown in FIG. 7, and the inner and outer diameters of the annular ring are contracted. In this case, the end portion of the dome portion 123 shrinks in the radial direction.

  In response to such displacement of the flange portion 124, the drip-proof cover 111 is displaced by the dome portion 123 connected to the flange portion 124. Then, when a voltage signal having a predetermined frequency is applied to the piezoelectric element 120, the vibrating body (111 + 120) resonates and generates a bending vibration as shown in FIG. This bending vibration has a plurality of nodes (reference numeral 420) that hardly vibrate in the bending direction. The plurality of nodes 420 are concentric circles with the optical axis O as the center when the dome portion 123 is formed by a curved surface, as exemplified in the present embodiment. In order to efficiently generate the bending vibration having the amplitude in the direction perpendicular to the surface of the dome portion 123, it is preferable to vibrate in the direction perpendicular to the end surface of the dome portion 123. The plate-like piezoelectric element 120 fixed to the flange portion 124 provided in the portion realizes this.

  The operation of the droplet evacuation apparatus 400 of this embodiment provided with the vibrator (111 + 120) having such a configuration is as follows.

  In FIG. 7, a droplet 500 or the like attached to a bending vibration region having an amplitude of the dome portion 123 of the drip-proof cover 111 becomes a plurality of minute droplets 501 due to the vibration, and each droplet scatters in the amplitude direction of the vibration ( Symbol F) in FIG. In this case, if the gravity direction is a direction orthogonal to the optical axis O (the direction of arrow G shown in FIG. 7), gravity is applied to each microdroplet 501, and most of them fall in the gravity direction G. Will be removed.

  However, at this time, due to, for example, the flow of air, the fine liquid droplets 501 scattered and separated from the surface of the drip-proof cover 111 may adhere to the surface of the dome portion 123 again. In addition, the micro droplet 501 may be attached to the bending vibration region of the dome portion 123 from the beginning. Since the acting force of the bending vibration by the piezoelectric element 120 is proportional to the mass of the droplet or the like, the generated force is small, and the above-described minute droplet 501 cannot be removed by bending vibration.

  However, it has been found that small droplets 501 with a small mass require a small amount of heat to evaporate. Accordingly, by heating the drip-proof cover 111 with the heater 130, the small liquid droplets 501 having a small mass attached to the surface of the drip-proof cover 111 can be evaporated in a very short time (reference numerals in FIG. 7). H). Thereby, the micro droplet 501 adhering to the dome part 123 is also removed. Even if the heater 130 is not installed, if the external environment is about room temperature, the fine droplet 501 is naturally evaporated and the droplet is removed from the dome.

  8 and 9 are diagrams schematically showing vibrations generated on the surface of the dome portion 123 of FIG. FIG. 8 shows only the outer surface of the dome portion 123 of FIG. FIG. 9 shows a state in which the vibration amplitude of FIG. 7 is not vibrated as an amplitude of 0. The vertical axis represents the amplitude, and the horizontal axis represents the angle θ from the optical axis O.

  FIG. 10 is a diagram schematically showing the resonant vibration of bending that occurs when a predetermined frequency higher than the frequency of the voltage applied to the piezoelectric element 120 to generate the vibration of FIG. 7 is applied to the piezoelectric element 120. It is. The vibration node positions in FIG. 9 and FIG. 10 are different, and when the voltages of the respective frequencies are sequentially applied to the piezoelectric element 120, the entire surface of the dome portion 123 has vibration amplitude and is attached to the dome portion 123. Droplets can be removed.

  Note that the droplet removing device 400 of the present embodiment is configured by providing a cover member 410 that covers the outer peripheral edge of the drip-proof cover 111. Accordingly, the liquid droplets or the like that flow down the gravity direction G along the outer surface of the drip-proof cover 111 are guided to the space 169 that serves as a receiving portion of the cover member 410 (collected by water introduction). For example, some of the micro droplets 501 removed from the surface of the dome portion 123 by the vibration action described above are configured to be received in the space 169 of the cover member 410. Then, the liquid droplets or the like that have entered the space 169 and accumulated in the space 169 can be easily discharged to the outside through the through hole 411 of the cover member 410 without affecting the drip-proof cover 111. it can.

  Next, the piezoelectric element control unit 109 of the droplet ejecting apparatus 400 in the present embodiment will be described below. FIG. 11 is a circuit diagram schematically showing the configuration of the piezoelectric element control unit in the droplet ejecting apparatus of the present embodiment. FIG. 12 is a time chart showing the form of each signal output from each component in the piezoelectric element control unit of FIG.

  The piezoelectric element control unit 109 has a circuit configuration as shown in FIG. 11, and the waveform signals (Sig1 to Sig4) shown in the time chart of FIG. 12 are generated in each part, and based on these signals, the following is performed. Controlled.

  As shown in FIG. 11, the piezoelectric element control unit 109 includes an N-ary counter 182, a 1/2 frequency divider circuit 183, an inverter 184, a plurality of MOS transistors Q00, Q01, Q02, a transformer 185, a resistor R00, and a voltage control circuit 186. It is composed of

  A ON / OFF switching operation of the MOS transistor Q01 and the MOS transistor Q02 connected to the primary side of the transformer 185 generates a signal (Sig4) having a predetermined period on the secondary side of the transformer 185. The piezoelectric element 120 is driven based on the signal of the predetermined period, and a resonant standing wave is generated in the drip-proof cover 111 to which the piezoelectric element 120 is fixed.

  In the following description, the piezoelectric element control unit 109 is described as being controlled by the microcomputer (Bucom) 214 on the body unit 200 side, but actually, the microcomputer (Bucom) on the body unit 200 side is described. ) 214 and the microcomputer (Lucom) 107 on the lens unit 100 side cooperate to perform a series of control processes. In the following description, in order to avoid complication, it is described mainly as control by the microcomputer (Bucom) 214 on the body part 200 side.

  The microcomputer (hereinafter referred to as Bucom) 214 on the body part 200 side is piezoelectric via three IO ports P_PwCont, IO port D_NCnt, IO port VCnt provided as control ports, and a clock generator 181 existing inside the Bucom 214. The element control unit 109 is controlled as follows.

  The clock generator 181 outputs a pulse signal (basic clock signal) to the N-ary counter 182 at a frequency sufficiently higher than the signal frequency applied to the piezoelectric element 120. This output signal is the signal Sig1 having the waveform shown in the time chart of FIG. The basic clock signal is input to the N-ary counter 182.

  The N-ary counter 182 counts the pulse signal and outputs a count end pulse signal every time it reaches a predetermined value “N”. That is, the basic clock signal is divided by 1 / N. This output signal is the signal Sig2 having the waveform shown in the time chart of FIG.

  In this divided pulse signal, the duty ratio between High and Low is not 1: 1. Therefore, the duty ratio is converted to 1: 1 through the 1/2 frequency dividing circuit 183. The converted pulse signal corresponds to the signal Sig3 having the waveform shown in the time chart of FIG.

  In the High state of the converted pulse signal, the MOS transistor Q01 to which this signal is input is turned on. On the other hand, this pulse signal is applied to MOS transistor Q02 via inverter 184. Therefore, in the low state of the pulse signal, the MOS transistor Q02 to which this signal is input is turned on. When the MOS transistor Q01 and the MOS transistor Q02 connected to the primary side of the transformer 185 are alternately turned on, a signal having a cycle such as the signal Sig4 in FIG. 12 is generated on the secondary side.

  The winding ratio of the transformer 185 is determined from the output voltage of the unit of the power supply circuit 218 and the voltage necessary for driving the piezoelectric element 120. The resistor R00 is provided to limit an excessive current flowing through the transformer 185.

  When driving the piezoelectric element 120, the MOS transistor Q00 must be in the ON state and a voltage must be applied from the power supply circuit 218 to the center tap of the transformer 185. In this case, ON / OFF control of the MOS transistor Q00 is performed via the IO port P_PwCont of the Bucom 217. The voltage control circuit 186 is controlled via the IO port VCnt of the Bucom 214 and controls the voltage applied to the primary side of the transformer 185. When the voltage on the primary side of the transformer 185 is changed, the voltage on the secondary side changes correspondingly, and the voltage applied to the piezoelectric element 120 changes. Then, the displacement amount of the piezoelectric element 120 changes, and the amplitude of the resonance bending vibration of the drip-proof cover 111 changes. Therefore, the voltage control circuit 186 can control the amplitude of the resonance bending vibration of the dustproof cover 111.

  The set value “N” of the N-ary counter 182 can be set from the IO port D_NCnt of the Bucom 214. Therefore, the Bucom 214 can arbitrarily change the drive frequency of the piezoelectric element 120 by appropriately controlling the set value “N”. is there.

At this time, the frequency can be calculated by the following equation (6). That is,
fdrv = fpls / 2N (6)
Here, N is a set value for the N-ary counter 182, fpls is a frequency of an output pulse of the clock generator 181, and fdrv is a frequency of a signal applied to the piezoelectric element 120. The calculation based on the equation (6) is performed in Bucom 214.

  Next, the control processing in the droplet removing apparatus 400 of the present embodiment will be described below with reference to FIGS. FIG. 13 and FIG. 14 are flowcharts of control processing in the droplet ejecting apparatus of this embodiment. Among these, FIG. 13 is a flowchart of the main control of the droplet removing apparatus of the present embodiment. FIG. 14 is a flowchart of the vibration operation by the body side microcomputer (Bucom).

  The control program related to the flowchart shown in FIG. 13 mainly operates in the Bucom 214 on the body part 200 side. This control program starts its operation (start) when a predetermined operation for activating the camera 1, for example, a power switch included in the operation unit 216 is turned on.

  First, in step S101, processing for starting the camera 1 is executed. That is, the Bucom 214 controls the power supply circuit 218 to start supplying power to each circuit unit constituting the camera 1. Also, initial setting operation of each circuit is executed.

  Next, in step S <b> 102, the Bucom 214 calls a vibration operation process, and executes a control process for controlling the piezoelectric element 120 via the piezoelectric element control unit 109 to vibrate the drip-proof cover 111. Details of this vibration operation processing will be described later with reference to a subroutine shown in FIG.

  Subsequently, in step S <b> 103, the Bucom 214 calls a heating operation process, and executes a control process for heating the drip-proof cover 111 by controlling the heater 130 via the heating control unit 110.

  Subsequently, in step S104, the Bucom 214 performs an imaging operation process. In this imaging operation process, image data sequentially acquired by driving the image sensor 202 is received, and after predetermined image processing is sequentially performed, the image data is stored in the recording medium 212 via the SDRAM 213 or the memory I / F. It is a series of processes to be recorded. This imaging operation process is the same as that performed in a general camera that acquires an image using a conventional imaging device.

  In step S <b> 105, the Bucom 214 controls the image processing unit 206, the foreign matter detection unit 201, and the like, and executes a foreign matter detection operation process for detecting whether or not foreign matter is present on the surface of the drip-proof cover 111. This foreign object detection operation process is an image process performed based on the image data acquired in step S104 described above (details have been described above).

  In step S106, the Bucom 214 checks whether or not a foreign object has been detected in the process of step S105 described above. If a foreign object is detected, the process proceeds to step S107. If no foreign object is detected, the process proceeds to step S108.

  When foreign substance detection is confirmed in the process of step S106 described above, when the process proceeds to step S107, the Bucom 214 executes a vibration operation change process for changing the vibration operation in step S107. This excitation operation changing process is a control process in which, for example, the output voltage of the voltage control circuit 186 is increased to apply a stronger vibration having a large vibration amplitude. Thereafter, the process returns to the above-described step S102. Further, even if the application time of the resonance bending vibration of the drip-proof cover 111 applied to the foreign matter such as droplets and dust is lengthened, the vibration energy acting on the foreign matter increases, and the effect of removing the foreign matter from the drip-proof cover 111 is obtained. Can be increased.

  The foreign object detection operation process described above is repeatedly and periodically performed. However, if the foreign object continues to be detected indefinitely and cannot be excluded, for example, the detection confirmation determination from step S106 to step S107. If the number of branches exceeds the predetermined number, the process branches to another processing sequence, where a warning display on the LCD 210 may continue to be issued and the original normal process may be returned. If the user (user) visually recognizes the warning display on the LCD 210, the user (user) can remove foreign matter by taking some forcible measures such as manually wiping the surface of the drip-proof cover 111. it can.

  Returning to FIG. 13, when the foreign substance detection is not confirmed in the process of step S106 described above and the process proceeds to step S108, the Bucom 214 continues to execute the normal vibration operation process and the heating operation process in step S108. .

  Subsequently, in step S109, the Bucom 214 continues to execute the imaging operation process.

  Next, in step S110, the Bucom 214 monitors an instruction signal generated from the operation unit 216 or the like, and confirms whether or not an instruction signal (imaging stop signal) for stopping the imaging operation is generated. Here, the imaging stop signal is, for example, an instruction signal for stopping the imaging operation or a power-off signal.

  If the imaging stop signal is confirmed in the process of step S110, the process proceeds to the next step S111. If the imaging stop signal is not confirmed, the process returns to step S108 described above.

  When the imaging stop signal is confirmed in the process of step S110 described above and the process proceeds to the process of step S111, the Bucom 214 controls the piezoelectric element control unit 109 to execute the excitation operation stop process in step S111.

  Subsequently, in step S112, the Bucom 214 controls the heating control unit 110 to execute a heating operation stop process. Thereafter, the series of processing sequence is ended (END).

  Next, details of the vibration operation processing sequence in step S102 of FIG. 13 will be described below with reference to FIG.

  First, in step S <b> 201 of FIG. 14, the Bucom 214 reads data from the flash memory 215 regarding the driving time (Toscf0) and the driving frequency (resonance frequency: Noscf0) for vibrating the drip-proof cover 111.

  Next, in step S202, the Bucom 214 outputs the drive frequency Noscf0 from the IO port D_NCnt to the N-ary counter 182 of the piezoelectric element control unit 109 and sets it (see FIG. 11).

  Subsequently, in step S203, the Bucom 214 sets the control flag P_PwCont to “Hi”. As a result, the piezoelectric element 120 vibrates the drip-proof cover 111 at a predetermined drive frequency (Noscf0), and executes a vibration operation that shakes off droplets attached to the surface of the drip-proof cover 111.

  Next, in step S204, the Bucom 214 stands by in a state where the drip-proof cover 111 is vibrated for a predetermined drive time (Toscf0).

  When the predetermined time (Toscf0) in step S204 described above has elapsed, subsequently, in step S205, Bucom 214 sets the control flag P_PwCont to “Lo”. As a result, the droplet removing operation is stopped. Thereafter, the process returns to the original processing sequence (return). In this case, the process returns to the flowchart of FIG. 13 and proceeds to the next step S103.

  Note that the vibration operation processing in the droplet ejecting apparatus of the present embodiment is not limited to the example described with reference to FIG. 13 described above, and other types of vibration operation processing may be considered. For example, the flowchart shown in FIG. 15 shows a modification of the vibration operation processing in the present embodiment. In the vibration operation processing of this modification, the operation of the drip-proof cover 111 is slightly different from the vibration operation processing in the embodiment described above with reference to FIG.

  That is, in the above-described embodiment, the drip-proof cover 111 is configured to generate a standing wave with the drive frequency of the drip-proof cover 111 set to f0 (fixed value). On the other hand, in this modified example, the drive frequency is sequentially changed and added, so that the change range of the resonance frequency is included without performing the strict drive frequency control for tracking the resonance frequency that changes due to the environmental temperature or the like. By sweeping a wide frequency band, a vibration with a large vibration amplitude is generated.

  In addition, when the shape and material of the drip-proof cover 111 change due to component variations during manufacturing, the resonance frequency may change greatly. Therefore, in order to make the driving of the piezoelectric element 120 for each product uniform, it is necessary to set an accurate resonance frequency for each product. In this case, the vibration speed may decrease when driven at a frequency other than the resonance frequency.

  Therefore, by applying frequency control as shown in this modification described below, it becomes possible to drive the piezoelectric element 120 by the resonance frequency even with a very simple control circuit, and thus resonance due to component variations during manufacturing. Even if there is a variation in frequency, it is possible to obtain an effect that appropriate control can always be performed.

  Hereinafter, frequency control in the vibration operation processing of this modification will be described with reference to the processing sequence of FIG.

  First, in step S211 of FIG. 15, the Bucom 214 performs a drive time (Toscf0), a drive start frequency (Noscfs), a frequency shift amount (Δf), and a drive end frequency (Noscfe) for vibrating the drip-proof cover 111. Are read from the flash memory 215.

  Next, in step S212, the Bucom 214 sets the drive start frequency (Noscfs) to the drive frequency (Noscf).

  Subsequently, in step S213, the Bucom 214 outputs the drive frequency (Noscf) from the IO port D_NCnt to the N-ary counter 182 of the piezoelectric element control unit 109 and sets it.

  In step S214, the Bucom 214 sets the control flag P_PwCont to “Hi”. Accordingly, the piezoelectric element 120 vibrates the drip-proof cover 111 at a predetermined driving frequency (Noscf), and causes the drip-proof cover 111 to generate standing wave vibration with a small vibration amplitude. Here, the droplets attached to the surface of the drip-proof cover 111 may not be removed if the vibration amplitude is small.

  In step S215, the Bucom 214 stands by in a state where the drip-proof cover 111 is vibrated for a predetermined drive time (Toscf0).

  When the predetermined time (Toscf0) in step S215 described above has elapsed, in step S216, the Bucom 214 performs a comparison determination as to whether or not the drive frequency (Noscf) = the drive end frequency (Noscfe). If it is determined that the two do not match (N determination), the process proceeds to step S217. If it is determined that the two match (Y determination), the process proceeds to the next step S218.

  When N is determined in the above-described step S216 and the process proceeds to step S217, the Bucom 214 adds the frequency shift amount (Δf) to the drive frequency (Noscf) in this step S217, and again the drive frequency (Noscf). ) Is set. Thereafter, the processing returns to the above-described step S213.

  When Y is determined in the process of step S216 described above and the process proceeds to the process of step S218, in this step S218, Bucom 214 sets P_PwCont to “Lo”. Thereby, the vibration operation of the piezoelectric element 120 is completed. Thereafter, the series of processing sequences is terminated, and the original processing sequence is returned (return).

  As described above, when the frequency is changed, the amplitude of the standing wave vibration increases. Therefore, if the drive start frequency (Noscfs), the frequency shift amount (Δf), and the drive end frequency (Noscfe) are set so as to pass the resonance frequency of the standing wave, the drip-proof cover 111 has a small vibration amplitude. It is possible to perform control such that vibration is first generated, the amplitude of the standing wave vibration gradually increases, becomes resonant vibration, and then the standing wave vibration amplitude decreases. If there is a vibration amplitude (vibration speed) that is greater than or equal to a predetermined value, it is possible to reliably remove droplets and the like attached to the surface of the drip-proof cover 111. Is possible. On the other hand, in one resonance bending mode, a vibration node (node line) may occur in the light beam passage region 170. In that case, it is only necessary to sequentially drive in different resonance bending modes by changing the driving frequency. When the resonance frequencies of a plurality of resonance bending modes are close, the driving is performed so that a plurality of resonance frequencies are included in the predetermined frequency range described above. You may do it.

  Further, if the drive start frequency (Noscfs) and the drive end frequency (Noscfe) are widened to some extent, it is caused by the temperature of the constituent unit composed of the piezoelectric element 120 and the drip-proof cover 111 and the variations that occur during the manufacture of these members. It is possible to absorb changes in the resonance frequency. Therefore, it is possible to reliably shake off the droplets adhering to the drip-proof cover 111 with an extremely simple circuit configuration.

  Furthermore, when there are a plurality of vibration modes having close resonance frequencies, the control time can be shortened and the control can be simplified by setting a drive frequency range including the plurality of vibration modes.

  As described above, according to the above-described embodiment, droplets and the like adhering to the surface of the curved (dome-shaped) drip-proof cover 111 are made minute by the vibration operation of the drip-proof cover 111 and reliably removed. In addition, even when droplets etc. that have been miniaturized by the vibration of the drip-proof cover 111 adhere to the surface of the drip-proof cover 111 again, those miniaturized droplets, etc. It is possible to evaporate in a short time by the heating operation of 111 and reliably eliminate it. Furthermore, the vibration operation of the drip-proof cover 111 can also shake off dust and the like adhering to the surface of the drip-proof cover 111.

  Therefore, the image apparatus to which the droplet removing apparatus 400 of the present embodiment is applied is a camera system that is often installed in a field or a place where a user (user) cannot easily reach, for example, for example, When applied to fixed-point observation cameras, surveillance or security camera systems, in-vehicle camera systems, etc., for example, rainwater droplets or cloudiness that adhere to the imaging light beam passage area on the front side of the imaging optical system due to rain, etc. Since dust and dust can be easily and reliably removed and removed, an image device that can always acquire a clear image can be obtained.

[Modification]
FIG. 16 is an exploded perspective view of a main part showing a modification of the dustproof cover and the piezoelectric element (vibrating body) in the droplet ejecting apparatus of the present embodiment (corresponding to FIG. 5 of the above-described embodiment). ).

  In the present modification, only the form of the piezoelectric element 120A and the portion (cylinder part 122) of the drip-proof cover 111 to which the piezoelectric element 120A is fixed and the flex 121 are different from the above-described embodiment. The piezoelectric element 120A in this modification is formed in a cylindrical shape. In the piezoelectric element 120A, a ground electrode 172 is formed on the inner peripheral surface, and a part thereof extends from one end surface and is drawn out to the outer peripheral surface. The signal electrode 171 is formed on the outer peripheral surface of the piezoelectric element 120A. In addition, the electrodes 171 and 172 are electrically connected to the corresponding electrodes with the flex 121 on the outer peripheral surface of the piezoelectric element 120A. The inner peripheral surface of the piezoelectric element 120A is a cylindrical surface, and the outer peripheral surface of the cylindrical portion 122 of the drip-proof cover 111 to be fixed is a cylindrical surface, so that stable fixing is possible. In addition, the outer peripheral surface of the piezoelectric element 120A is also a cylindrical surface, and the flexible plate-like flexible member 121 can be securely fixedly connected. It is also easy to manufacture the cylindrical piezoelectric element 120A from ceramic.

  The cylindrical piezoelectric element 120A formed in this way covers the outer peripheral surface of the cylindrical portion 122 of the drip-proof cover 111, that is, covers the cylinder of the drip-proof cover 111 on the inner peripheral side of the piezoelectric element 120A. It arrange | positions so that the part 122 may be fitted, and it adheres to the drip-proof cover 111 by adhesion | attachment etc.

  In this modified example having such a configuration, the outer diameter of the flange portion 124 of the drip-proof cover 111 can be further reduced by applying the cylindrical piezoelectric element 120A. In addition, when setting it as the structure shown in this modification, the drip-proof seal | sticker 150 should just support it, sealing only the drip-proof cover 111 (outer edge part of the flange part 124). Therefore, when forming the watertight structure in the droplet evacuating apparatus 400A, a simpler structure can be achieved, thereby contributing to downsizing as a whole.

  As an example of the watertight structure of the drip-proof cover 111, for example, a circumferential groove is formed on the outer peripheral surface of the flange portion 124 of the drip-proof cover 111, and the circumferential groove is made of, for example, a rubber material or the like. A configuration in which an O-ring-shaped drip-proof seal is fitted and arranged is conceivable.

  FIGS. 17-20 is a figure which shows the other modification about the dust-proof cover and piezoelectric element (vibrating body which consists of) in the droplet removal apparatus of this embodiment. Among these, FIG. 17 is a plan view showing a signal electrode surface of the piezoelectric element (corresponding to FIG. 6 of the above-described embodiment). FIG. 18 is a diagram conceptually showing the polarization configuration of the piezoelectric element. FIG. 19 conceptually shows vibration amplitude generated at a certain latitude when the dome 123 is viewed from the optical axis O direction. FIG. 20 is a diagram illustrating the vibration of FIG. 19 with the horizontal axis representing the circumferential angle φ.

  In the present modification, the piezoelectric element 120B is formed so as to be a plate-like ring as in the above-described embodiment. In the modified example, the polarization of the piezoelectric element 120B is formed in a form different from that of the one embodiment. That is, in this modification, as shown in FIG. 17, the polarization regions having the same shape in the circumferential direction are arranged so that the angles are substantially equal in the circumferential direction, and the polarization directions are alternately arranged along the circumferential direction. The direction is reversed.

  A frequency voltage is applied to the entire polarization region by the signal electrode 171. Then, in the piezoelectric element 120B, areas that contract in the same manner as areas extending in the circumferential direction are alternately generated. When a voltage having a predetermined frequency is applied to the piezoelectric element 120B, the surface of the dome 123 is formed as shown in FIGS. Vibration occurs. In the case of the configuration of this modification, the resonance bending vibration generated in the dome portion 123 generates a vibration node 420 along the meridian of the dome portion 123 (see FIG. 19).

  Since the bending vibration of the present modification also has a vibration node 420, it is configured to eliminate droplets and the like attached to the dome portion 123 by combining with a different vibration. For example, when the piezoelectric element 120B of this modification is driven by the voltage of the resonance frequency shown in the above-described embodiment, the vibration shown in the above-described embodiment can be easily generated.

  In each embodiment of the present invention, as a device for imaging, a camera that uses an image sensor and handles digital image data has been described as an example. However, as a camera to which the droplet ejecting apparatus of the present invention can be applied, For example, it may be a lens type camera or a single-lens reflex type or a compact type digital camera. Furthermore, a video camera such as a video camera or a movie camera may be used. In addition, of course, it may be a camera built in a personal digital assistant (PDA) including a mobile phone, a smartphone, or the like. Also, it may be an industrial or medical optical device such as an endoscope or a microscope that is an optical device used in an environment where droplets adhere, and it may be a surveillance camera, an on-vehicle camera, a stationary type. In addition to the above-mentioned cameras, for example, a camera attached to a television receiver, a personal computer, or the like can cause the same problem, so the technique of the present invention can be applied.

  Note that each process sequence described in each of the above-described embodiments can allow a change in procedure as long as it does not contradict its nature. Therefore, for each of the above-described processing sequences, for example, the order of the processing steps is changed each time the processing order is changed, the processing steps are executed simultaneously, or a series of processing sequences are executed. It may be. That is, regarding the operation flow in the claims, the specification, and the drawings, even if it is described using “first,” “next,” etc. for convenience, it is essential to carry out in this order. It doesn't mean. In addition, it goes without saying that the steps constituting these operation flows can be omitted as appropriate for portions that do not affect the essence of the invention.

  Of the technologies described here, many of the controls and functions described mainly in the flowcharts are often settable by a software program. The computer program reads and executes the software program described above. Control and functions can be realized. The software program is stored in advance as a computer program product in the product manufacturing process, such as the above-mentioned storage medium or storage unit, specifically, a portable medium such as a flexible disk or CD-ROM, a non-volatile memory, a hard disk, a volatile Electronic data stored or recorded in whole or in part in a storage medium such as a volatile memory. Apart from this, it can be distributed or provided at the time of product shipment or via a portable medium or a communication line. Users can operate by downloading their software programs and installing them on a computer via a communication network, the Internet, etc., or installing them on a computer from a storage medium even after the product has been shipped. As a result, the imaging apparatus of the present embodiment can be easily realized.

  The present invention is not limited to the above-described embodiments, and it is needless to say that various modifications and applications can be implemented without departing from the spirit of the invention. Further, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if several constituent requirements are deleted from all the constituent requirements shown in the above-described embodiment, if the problem to be solved by the invention can be solved and the effect of the invention can be obtained, this constituent requirement is deleted. The configured structure can be extracted as an invention. Furthermore, constituent elements over different embodiments may be appropriately combined. The invention is not limited by the specific embodiments thereof, except as limited by the appended claims.

  The present invention is not limited to the liquid drop removing device applied to the image device in the in-vehicle camera system, the surveillance or security camera system, etc., and other forms of the image device, for example, for observation used in a wet environment test chamber Moving images or still images used for various purposes such as cameras, so-called action cameras that are attached to athletes in sports competitions, etc., and observation cameras that are mounted on small model aircraft (so-called drones, etc.) and used in outdoor environments The present invention can be widely applied to image capturing cameras.

  Further, the present invention can also be applied to an illumination device having a cover member that covers an illumination light source, such as a headlight or taillight used for vehicles such as automobiles, trains, and aircraft.

  Furthermore, the present invention can be similarly applied to an observation apparatus provided with a Hankyu-shaped (dome-shaped) drip-proof cover member on the front side of the optical system, for example, a telescope, binoculars, and monoculars.

  Furthermore, the present invention can be similarly applied to an imaging optical system for image recognition in a robot or the like.

  In addition to these, the present invention can be similarly applied to, for example, a projection type image display apparatus that enlarges and projects an image using a transmission type liquid crystal display apparatus or the like.

1 …… Camera,
100 …… Lens part,
101 …… Focus lens,
102 …… Variable lens,
103 …… Aperture,
104, 105, 106 ... driver,
107 …… Microcomputer,
108 …… Flash memory,
109 …… Piezoelectric element control unit,
110... Heating control unit,
111 …… Drip-proof cover,
118 …… Front lens,
120, 120A, 120B ... Piezoelectric element,
121 …… Flexible printed circuit board,
122 …… Cylinder part,
123 …… Dome part,
124 …… Flange part,
130 …… Heater,
131 …… Flexible printed circuit board,
140 …… Support frame,
141 …… Drip-proof cover receiving part,
142 …… Rotation stop protrusion,
145 ... through opening,
146 ... positioning protrusion,
149 .... first internal space,
150 …… Drip-proof seal,
151 …… Pressing member,
152 …… Screw,
153 ....... Pressure receiving protrusion,
154 ... Projection piece,
159 ... the second internal space,
160 …… Dust-proof seal,
169 ... space,
170 ....... light flux passage region,
171, 172 ... Electrodes,
172a ...... side electrode,
181 ... Clock generator,
182 ... N-ary counter,
183 ... 1/2 frequency divider,
184 …… Inverter,
185 ... Trans,
186 ... Voltage control circuit,
200 …… Body part,
201 ... Foreign matter detection unit,
202 …… Image sensor,
203 …… Analog processing unit,
204... A / D converter,
205... AE processing unit,
206 …… Image processing unit,
207 …… AF processing unit,
208 …… Image compression / decompression unit,
209 …… LCD driver,
210 …… LCD,
211 …… Memory I / F,
212 …… Storage medium,
213 ... SDRAM,
214 …… Microcomputer,
215: Flash memory,
216 ... operation unit,
217 ... Internal bus,
218 …… Power supply circuit,
300 …… Interface (I / F),
400, 400A ... Droplet eliminator,
401... Vibration control device,
402... Heating control device,
410 …… Cover member,
411 …… through hole,
420 …… Section,
500 …… Droplets, etc.
501: Fine droplets,

Claims (12)

An optical element having a light beam passage region for passing a light beam for forming an optical image, and having a curved dome portion;
It is connected to the end of the curved surface forming the dome portion of the optical element, and is provided in an installation portion formed by a surface having a curvature of 0 in at least one direction, and generates bending vibration in the dome portion of the optical element. A vibration member;
A vibration control device for controlling the excitation member;
A droplet ejecting apparatus comprising: The optical element is formed with a plane part composed of a surface having a curvature in two directions of 0 in the installation part,
The droplet ejecting apparatus according to claim 1, wherein the vibration member is a piezoelectric body fixed to the flat portion and formed in a plate shape. A support frame for mounting and fixing the optical element;
A holding member provided in close contact with the outer peripheral edge of the planar portion of the optical element, and holding and holding the optical element and having vibration absorption;
Further comprising
The droplet removing device according to claim 2, wherein the holding member makes an internal space formed by the optical element, the holding member, and the support frame watertight with respect to the external space. A cover member that covers the installation portion of the optical element and has an opening that allows the light beam forming the optical image to pass therethrough is further provided,
The cover member is formed to have a receiving portion that receives liquid droplets separated from the outer surface of the optical element, and a drain port that discharges the liquid droplets received by the receiving portion to the outside. The droplet ejecting apparatus according to any one of claims 1 to 3. A heating member that is connected to an end of the curved surface forming the dome portion of the optical element and is provided in an installation portion formed by a surface having a curvature of 0 in at least one direction, and heating the optical element;
A heating control device for controlling the heating member;
The droplet removing device according to any one of claims 1 to 4, further comprising: An optical element having a light beam passage region for passing a light beam for forming an optical image, and having a curved dome portion;
An excitation member connected to a curved surface forming the dome portion of the optical element and provided in an installation portion formed of a surface having at least one curvature in one direction, and generates bending vibration in the dome portion of the optical element When,
A heating member connected to the curved surface forming the dome portion of the optical element and provided in an installation portion formed by a surface having a curvature of 0 in at least one direction, and heating the optical member;
A vibration control device for controlling the excitation member;
A heating control device for controlling the heating member;
A droplet ejecting apparatus comprising: A lens unit having an imaging optical system for forming an optical image;
A body portion having an image sensor;
A droplet evacuation device according to any one of claims 1 to 6,
An image apparatus comprising:   The droplet ejecting device is disposed on the front side of the lens unit, and a part of the tip side of the lens unit is disposed in the inner space of the dome portion of the optical element of the droplet ejecting device. The image apparatus according to claim 7, wherein   A method for controlling a droplet removing apparatus, comprising performing an exciting operation for generating a bending vibration in a dome portion of an optical element.   The method for controlling a droplet removing apparatus according to claim 9, further comprising a heating operation for heating the optical element.   A control program for a droplet ejecting apparatus, which causes a computer to execute a method for controlling a droplet ejecting apparatus including an excitation step for generating bending vibration in a dome portion of an optical element.   12. The control program for a droplet discharge device according to claim 11, wherein the computer executes a control method for the droplet discharge device further including a heating step for heating the optical element.

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