JP2006203533A - Electronic imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic imaging apparatus which can normally, reliably and excellently perform a dust elimination operation without imposing much burden on a battery to be mounted as the power source of the apparatus. <P>SOLUTION: The imaging apparatus includes: a light transmittable dust-proofing filter 21 on the light receiving part of an imaging element 27; and a vibrating means for vibrating the dust-proofing filter 21. The timing of the operation by the vibrating means is controlled by considering the driving of a main mirror 13b. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electronic image pickup apparatus having a dustproof function for preventing dust from adhering to an image pickup element.

  In a single-lens reflex digital camera with interchangeable lenses, dust floating in the air may enter the camera body when the photographic lens is removed from the camera body. In addition, since various mechanisms that operate mechanically such as a shutter and a diaphragm mechanism are disposed inside the camera, dust may be generated during the operation from these mechanisms.

  There is a problem that these dusts adhere to the surface of the image sensor inside the camera and affect the captured image.

  As a countermeasure, a dustproof member that seals or protects the light receiving portion of the image sensor is provided, and it is possible to suppress dust and the like from adhering to the light receiving portion of the image sensor, and for dust that adheres to the surface of the dustproof member. In recent years, many techniques have been proposed for removing predetermined vibrations by applying predetermined vibrations to the dust-proof members by means of vibration.

  For example, regarding a technique for removing dust by applying vibration to a dustproof member, there is an example in which vibration is started at least during an imaging operation of an imaging device (for example, Patent Document 1). In this case, it vibrates even during substantial exposure, but if it is only during exposure, the dust removal effect is less when the shooting shutter speed is set short, so the dust removal operation is started earlier than the imaging operation. Yes.

As another example, in consideration of the timing of applying vibration to the dustproof member, vibration is given during the imaging operation of the first image sensor during the continuous shooting mode, and vibration is not applied after the second image. There is (for example, Patent Document 2).
JP 2004-23159 A Japanese Patent Application No. 2003-30876

  A large electric power is required for the dust removing operation for removing the dust by applying vibration to the dustproof member. However, in the case of a single-lens reflex camera, mirror up and aperture drive are performed immediately before the imaging operation of the imaging device, and performing the dust removal operation simultaneously with those operations is a battery mounted as a power source of the device There is a problem that a great load is applied to the device. If a large load is applied to the battery, the operation of the camera will be hindered.

  Depending on the shooting mode, the lens drive operation may be executed during the mirror up operation. However, performing the dust removal operation at that time will still put a great load on the battery.

  In view of the above circumstances, an object of the present invention is to provide an electronic imaging device that can always perform a reliable and good dust removing operation without applying a great load to a battery mounted as a power source of the device. .

  An electronic imaging apparatus according to a first aspect of the present invention includes an imaging element, and a translucent member provided on a light receiving portion of the imaging element, and an excitation unit that vibrates the translucent member; And control means for controlling the operation timing of the vibration means.

  According to a second aspect of the present invention, there is provided an electronic imaging apparatus according to the first aspect of the present invention, further comprising: a mirror that is raised before the imaging operation of the imaging device and is lowered after the imaging operation; a mirror driving unit that drives the mirror; It has. Then, the control means operates the excitation means at a timing before the driving of the mirror driving means at the first control for operating the excitation means at a timing parallel to the driving of the mirror driving means, and ends the operation. Any one of the second controls is selectively executed.

  According to a third aspect of the present invention, there is provided an electronic imaging apparatus according to the second aspect of the present invention, further comprising determination means for determining a capacity of a battery mounted as a power source of the apparatus. The control means executes the first control when the capacity determined by the determination means is greater than or equal to a predetermined value, and executes the second control when the capacity determined by the determination means is less than the predetermined value.

  According to a fourth aspect of the present invention, there is provided an electronic imaging apparatus according to the second aspect of the present invention, further comprising selection means for selecting a photographing mode. The control unit executes the second control when the shooting mode selected by the selection unit is a moving body mode suitable for shooting a moving subject, and the shooting mode selected by the selection unit is not the moving body mode. In this case, the first control is executed.

  According to a fifth aspect of the present invention, there is provided an electronic imaging apparatus according to the second aspect, further comprising: an imaging optical system that projects an optical image of a subject onto an imaging device; and a focus detection unit that performs focus detection of the imaging optical system; It is equipped with. The timing before driving of the mirror driving means is at least during the operation of the focus detection means.

  The electronic imaging device of the invention according to claim 6 is limited to the translucent member in the invention according to claim 1 or claim 2. That is, the translucent member is a translucent dustproof filter provided in a state of covering the light receiving portion of the image sensor.

  According to the present invention, the dust removal operation timing is controlled in accordance with the power capacity of the battery or the shooting mode, so that a reliable and good dust is always obtained without imposing a great load on the battery mounted as the power source of the apparatus. An electronic imaging apparatus capable of removing operation can be provided.

  The electronic image pickup apparatus of the present invention illustrated below is an apparatus having a dustproof function of an image pickup element unit that obtains an image signal by photoelectric conversion, and here, as an example, will be described as an improved technique related to dustproof of an electronic camera. In particular, a single-lens reflex electronic camera (digital camera) with interchangeable lenses will be described.

[1] First embodiment
First, FIG. 1 is a diagram for explaining a concept of a main part of a camera that is an electronic imaging apparatus of the first embodiment.

  An imaging element (CCD) 104 is provided on a path through which incident light from a subject passes through a main mirror (also referred to as a main mirror) 101, a sub mirror 102, and a shutter 103, and covers a light receiving portion of the imaging element 104. A light-transmitting dustproof filter 105 is provided. Dust that tends to adhere to the light receiving part of the image sensor 104 adheres to the dustproof filter 105 and does not adhere to the light receiver of the image sensor 104. When the dustproof filter 105 is driven by the dustproof filter driving unit 200, dust attached to the dustproof filter 105 is removed and removed.

  The drive timing of the dustproof filter driving unit 200 is determined by the sequence control unit 201. The sequence control unit 201 is connected to a capacity determination unit 202 that determines the power capacity of a battery that is a power source of the camera, and a mode setting unit 203 that sets a shooting mode of the camera. The sequence control unit 201 determines the operation timing of the dustproof filter driving unit 200 based on the determination result of the capacity determination unit 202 and the photographing mode set by the mode setting unit 203.

  An example of the operation of the single-lens reflex electronic camera is shown in FIG. 1 as a sequence along the flow of time t. That is, after one frame is shot by the image pickup operation of the image sensor 104, the main mirror 101 is lowered (204), followed by an autofocus (AF) operation (AF sensor integration & AF calculation) (205), and then a continuous shooting mode. In this case, the main mirror 101 is raised to start photographing the next frame (206), and when the up is completed, an exposure (imaging) operation (207) to the image sensor 104 is reached. During this sequence, depending on the shooting mode, lens driving (208) based on the AF operation is performed in parallel with the mirror-up operation.

  In such a camera sequence, the sequence control unit 201 sets the dust filter driving unit 200 to the first timing t1 before the mirror driving is finished and the next mirror driving is started, or the second timing t2 parallel to the mirror driving. To make it work.

  The specific configuration of the camera is shown in FIGS. 2 and 3 below. FIG. 2 is a perspective view schematically showing a mechanical internal structure by cutting a part of the camera. FIG. 3 is a block diagram schematically showing mainly the electrical configuration of the camera. First, the mechanical structure will be described.

  The camera 1 includes a camera main body 11 and a lens barrel 12 that are configured separately, and are configured to be detachable from each other.

  The lens barrel 12 is configured by internally holding a photographing optical system 12a including a plurality of lenses and their driving mechanisms, and the photographing optical system 12a is formed by the subject light flux by transmitting the light flux from the subject. For example, a plurality of optical lenses are used so that an image of a subject to be imaged is formed at a predetermined position (on a light receiving surface of an image sensor 27 described later). The lens barrel 12 is disposed so as to protrude toward the front surface of the camera body 11.

  The lens barrel 12 is the same as that generally used in conventional cameras and the like. Therefore, the detailed description of the configuration is omitted.

  The camera main body 11 includes various constituent members and the like, and is a photographic optical system that is a connecting member for detachably mounting the lens barrel 12 that holds the photographic optical system 12a. This is a so-called “single-lens reflex camera” configured to include the mounting portion 11a on the front surface thereof.

  That is, an exposure opening having a predetermined aperture capable of guiding the subject light beam into the camera body 11 is formed at a substantially central portion on the front side of the camera body 11, and the exposure opening has a peripheral edge. A photographing optical system mounting portion 11a is formed.

  On the outer surface side of the camera main body 11, the above-described photographing optical system mounting portion 11 a is disposed on the front surface thereof, and various types for operating the camera main body 11 at predetermined positions such as an upper surface portion and a back surface portion. For example, a release button 17 for generating an instruction signal or the like for starting the photographing operation is provided. Since these operation members are not directly related to the present invention, the illustration and description of the operation members other than the release button 17 are omitted in order to avoid complication of the drawing.

  Inside the camera main body 11, various constituent members as shown, for example, on a light receiving surface of an image sensor (corresponding to the image sensor 104) 27 described later for a desired subject image formed by the imaging optical system 12 a. A finder device 13 which is provided to form a predetermined position different from the above, and forms a so-called “observation optical system”, and a shutter which controls the irradiation time of a subject light beam on a light receiving surface of an image sensor 27 which will be described later (on the shutter 103) 14), an image sensor 27 to be described later, which is a photoelectric conversion element for obtaining an image signal corresponding to a subject image formed on the basis of the subject light flux that has passed through the photographing optical system 12a and the shutter 14, and a light receiving surface of the image sensor 27 A dust-proof filter 21 (corresponding to the dust-proof filter 105 described above), which is a translucent member disposed so as to cover the light-receiving surface and preventing dust and the like from adhering to the light receiving surface. The main unit is mounted with an image pickup unit 15 composed of the image pickup unit 15, which will be described in detail later), and various electric members constituting an electric circuit such as an image signal processing circuit that performs various signal processing on the image signal acquired by the image pickup device 27. A plurality of circuit boards including the circuit board 16 (only the main circuit board 16 is shown in FIG. 2) are disposed at predetermined positions.

  The finder device 13 includes a main mirror (corresponding to the main mirror 101) 13b configured to bend the optical axis of a subject light beam that has passed through the photographing optical system 12a and guide it to the observation optical system side, and the main mirror. A pentaprism 13a that receives a light beam emitted from 13b and forms an erect image, and an eyepiece 13c that forms an image in an optimum form for magnifying and observing the image formed by the pentaprism 13a. Has been.

  The main mirror 13b is configured to be movable between a position retracted from the optical axis of the photographic optical system 12a and a predetermined position on the optical axis, and the normal state is on the optical axis of the photographic optical system 12a. It is arranged at a predetermined angle with respect to the optical axis, for example, at an angle of 45 °. As a result, when the camera 1 is in the normal state, the subject luminous flux transmitted through the photographing optical system 12a is bent by the main mirror 13b, and the pentaprism 13a disposed above the main mirror 13b. Reflected to the side of the.

  On the other hand, while the camera 1 is performing a photographing operation, during the actual exposure operation, the main mirror 13b moves to a predetermined position retracted from the optical axis of the photographing optical system 12a. As a result, the subject light flux is guided to the image pickup device 27 side and irradiated on the light receiving surface thereof.

  The shutter (corresponding to the shutter 103) is the same as that generally used in conventional cameras, such as a focal plane type shutter mechanism and a drive circuit for controlling the operation of the shutter mechanism. Applies. Therefore, the detailed description of the configuration is omitted.

  The electrical description based on FIG. 3 will be described in detail later, and then the detailed structure of the imaging unit 15 in the camera 1 will be described below.

  4, 5, and 6 show a part of the image pickup unit 15 in the camera 1. FIG. 4 is an exploded perspective view of the main part showing the image pickup unit 15 in an exploded state, and FIG. 5 is an assembled state. FIG. 6 is a cross-sectional view taken along the cut surface of FIG. 5.

  The imaging unit 15 of the camera 1 is a unit composed of a plurality of members including the shutter 14 as described above. However, in FIGS. 4 to 6, only the main part is illustrated, and the shutter 14 is illustrated. Is omitted. 4 to 6, in order to show the positional relationship of each component, an image pickup device 27 provided in the vicinity of the image pickup unit 15 is mounted and an image pickup system electric circuit including an image signal processing circuit and a work memory is provided. A main circuit board 16 on which a circuit is mounted is also illustrated. The details of the main circuit board 16 itself are assumed to be those commonly used in conventional cameras and the like, and the description thereof is omitted.

  The imaging unit 15 is composed of a CCD or the like, and has an imaging element 27 that obtains an image signal corresponding to light that is transmitted through the imaging optical system 12a and irradiated on its own light receiving surface, and a thin plate-like member that fixes and supports the imaging element 27 An image sensor fixing plate 28 and an optical low-pass filter (Low) formed on the light receiving surface side of the image sensor 27 and formed to remove a high-frequency component from a subject luminous flux that is transmitted through the imaging optical system 12a. Pass Filter (hereinafter referred to as “optical LPF”) 25, a low-pass filter receiving member 26 that is disposed at a peripheral portion between the optical LPF 25 and the image sensor 27 and is formed by a substantially frame-shaped elastic member or the like, and imaging The element 27 is housed and fixedly held, and the optical LPF 25 is supported in close contact with the peripheral portion or the vicinity thereof, and a predetermined portion is described later. An image sensor housing case member 24 (second member to be described later; hereinafter referred to as “CCD case 24”) disposed so as to be in close contact with a first member (to be described later), and the front side of the CCD case 24 And a dustproof filter receiving member 23 (first member) that supports the dustproof filter 21 (dustproof member) in close contact with the peripheral portion or the vicinity thereof, and the image pickup device 27 supported by the dustproof filter receiving member 23. A dust-proof filter 21 that is a translucent member disposed at a predetermined position having a predetermined interval between the optical LPF 25 and the optical LPF 25 on the front side of the optical LPF 25 so as to cover the light-receiving surface of the optical LPF 25, and the periphery of the dust-proof filter 21 Exciting means, for example, a piezoelectric element 22 that is disposed in the section and vibrates the dustproof filter 21, and a dustproof filter described later that is a drive circuit that drives the piezoelectric element 22 Moving circuit 48 (corresponding to the dustproof filter driving unit 200, not shown in FIGS. 4 to 6, see FIG. 3) and the dustproof filter 21 are hermetically joined to the dustproof filter receiving member 23 and fixedly held. It is comprised by the press member 20 etc. which consist of the elastic body which carries out.

  The image sensor 27, which is a photoelectric conversion means, receives the subject luminous flux transmitted through the photographing optical system 12a on its own light receiving surface and performs a photoelectric conversion process, thereby obtaining an image signal corresponding to the subject image formed on the light receiving surface. For example, a charge coupled device (CCD) is applied.

  The image sensor 27 is mounted at a predetermined position on the main circuit board 16 via the image sensor fixing plate 28. On the main circuit board 16 (not shown), the image signal processing circuit and the work memory are mounted together as described above, and an output signal from the image sensor 27, that is, an image signal obtained by photoelectric conversion processing is processed. The

  An optical LPF 25 is disposed on the front side of the image sensor 27 with a low-pass filter receiving member 26 interposed therebetween. A CCD case 24 is disposed so as to cover it.

  That is, the CCD case 24 is provided with a rectangular opening 24c at a substantially central portion, and the optical LPF 25 and the image sensor 27 are disposed in the opening 24c from the rear side. A step portion 24a having a substantially L-shaped cross section as shown in FIGS. 5 and 6 is formed on the inner peripheral edge portion on the rear side of the opening 24c.

  As described above, the low-pass filter receiving member 26 made of an elastic member or the like is disposed between the optical LPF 25 and the image sensor 27. The low-pass filter receiving member 26 is disposed at a position that avoids the effective range of the light receiving surface at the peripheral portion on the front surface side of the image sensor 27 and comes into contact with the vicinity of the peripheral portion on the back surface side of the optical LPF 25. Yes. The optical LPF 25 and the image sensor 27 are configured to maintain substantially airtightness. Thereby, an elastic force in the optical axis direction by the low-pass filter receiving member 26 acts on the optical LPF 25.

  Therefore, by arranging the peripheral portion on the front side of the optical LPF 25 so as to be in substantially airtight contact with the stepped portion 24a of the CCD case 24, the optical LPF 25 is designed to be displaced in the optical axis direction. The position of the optical LPF 25 in the optical axis direction is restricted against the elastic force of the filter receiving member 26. In other words, the position of the optical LPF 25 inserted from the back side into the opening 24c of the CCD case 24 is regulated in the optical axis direction by the step portion 24a. Thus, the optical LPF 25 is prevented from coming out from the inside of the CCD case 24 toward the front side.

  Thus, after the optical LPF 25 is inserted into the opening 24c of the CCD case 24 from the back side, the image sensor 27 is disposed on the back side of the optical LPF 25. In this case, a low-pass filter receiving member 26 is sandwiched between the optical LPF 25 and the image sensor 27 at the peripheral edge.

  Further, as described above, the image sensor 27 is mounted on the main circuit board 16 with the image sensor fixing plate 28 interposed therebetween. The imaging element fixing plate 28 is fixed to the screw hole 24e from the back side of the CCD case 24 with a screw 28b via a spacer 28a. Further, the main circuit board 16 is fixed to the image sensor fixing plate 28 with screws 16d through spacers 16c.

  On the front side of the CCD case 24, a dustproof filter receiving member 23 is fixed to the screw hole 24b of the CCD case 24 by screws 23b. In this case, a circumferential groove 24d is formed in a substantially annular shape at a predetermined position on the peripheral side of the CCD case 24 and on the front side, as shown in detail in FIGS. On the other hand, an annular convex portion 23d (not shown in FIG. 4) corresponding to the circumferential groove 24d of the CCD case 24 is provided at a predetermined position on the peripheral side of the dust-proof filter receiving member 23 on the back side. It is formed in a substantially annular shape over the entire area. Therefore, the CCD case 24 and the dustproof filter receiving member 23 are mutually connected in the annular region, that is, in the region where the circumferential groove 24d and the annular convex portion 23d are formed by fitting the annular convex portion 23d and the circumferential groove 24d. It fits in a substantially airtight manner.

  The dustproof filter 21 has a circular or polygonal plate shape as a whole, and at least a region having a predetermined spread in the radial direction from its own center forms a transparent portion, and this transparent portion is the front side of the optical LPF 25. Are opposed to each other with a predetermined interval.

  Further, a peripheral portion of one surface of the dustproof filter 21 (the back side in the present embodiment) is a predetermined vibration member for applying vibration to the dustproof filter 21, and is provided by an electromechanical conversion element or the like. For example, the piezoelectric elements 22 to be formed are arranged by means such as adhesion using an adhesive. The piezoelectric element 22 is configured to generate a predetermined vibration, that is, a standing wave vibration, in the dust filter 21 when a drive pulse voltage having a predetermined period is applied from a dust filter driving circuit 48 described later. Yes. The dustproof filter 21 is fixed and held by a pressing member 20 made of an elastic body such as a leaf spring so as to be airtightly joined to the dustproof filter receiving member 23.

  In the vicinity of the substantially central portion of the dustproof filter receiving member 23, an opening 23f having a circular shape or a polygonal shape is provided. The opening 23f is set to have a size sufficient to transmit the subject light beam that has passed through the photographing optical system 12a and to irradiate the light receiving surface of the image sensor 27 disposed behind.

  A wall portion 23e (see FIGS. 5 and 6) protruding to the front surface side is formed in a substantially annular shape at the peripheral portion of the opening 23f, and further toward the front surface side at the distal end side of the wall portion 23e. A receiving portion 23c is formed so as to protrude.

  On the other hand, in the vicinity of the outer peripheral edge portion on the front surface side of the dustproof filter receiving member 23, a plurality of (three in the present embodiment) protruding portions 23a are formed to protrude toward the front surface side at predetermined positions. The protruding portion 23a is formed to fix the pressing member 20 that fixes and holds the dustproof filter 21, and the pressing member 20 is fixed to the tip portion of the protruding portion 23a by a screw 20a or the like. .

  The pressing member 20 is a member formed of an elastic body such as a leaf spring as described above, and its base end is fixed to the projecting portion 23a, and its free end abuts against the outer peripheral edge of the dust filter 21. By contacting, the dustproof filter 21 is pressed toward the dustproof filter receiving member 23 side, that is, in the optical axis direction.

  In this case, the positions of the dust filter 21 and the piezoelectric element 22 in the optical axis direction are adjusted by contacting a predetermined portion of the piezoelectric element 22 disposed on the outer peripheral edge on the back side of the dust filter 21 with the receiving portion 23c. Being regulated. Accordingly, the dustproof filter 21 is thereby fixed and held so as to be airtightly joined to the dustproof filter receiving member 23 via the piezoelectric element 22.

  In other words, the dustproof filter receiving member 23 is configured to be airtightly bonded via the dustproof filter 21 and the piezoelectric element 22 by the urging force of the pressing member 20.

  By the way, as described above, the dustproof filter receiving member 23 and the CCD case 24 are set so that the circumferential groove 24d and the annular convex portion 23d (see FIGS. 4 and 5) are fitted in a substantially airtight manner. At the same time, the dustproof filter receiving member 23 and the dustproof filter 21 are set so as to be airtightly joined via the piezoelectric element 22 by the urging force of the pressing member 20. The optical LPF 25 disposed in the CCD case 24 is disposed so as to be substantially airtight between the peripheral portion on the front side of the optical LPF 25 and the step portion 24 a of the CCD case 24. Furthermore, an image sensor 27 is disposed on the back side of the optical LPF 25 via a low-pass filter receiving member 26, so that substantially airtightness is maintained between the optical LPF 25 and the image sensor 27. Yes.

  Accordingly, a predetermined gap 51a is formed in the space between the optical LPF 25 and the dustproof filter 21 facing each other. Further, the peripheral portion of the optical LPF 25, that is, the space 51 b is formed by the CCD case 24, the dustproof filter receiving member 23, and the dustproof filter 21. The space portion 51b is a sealed space formed so as to protrude outside the optical LPF 25 (see FIGS. 5 and 6). The space 51b is set to be a larger space than the gap 51a. The space composed of the gap 51a and the space 51b becomes a sealed space 51 that is sealed almost airtight by the CCD case 24, the dustproof filter receiving member 23, the dustproof filter 21, and the optical LPF 25 as described above. ing.

  As described above, in the imaging unit 15 in the camera 1, a sealing structure portion is formed that forms a substantially sealed space 51 that is formed on the periphery of the optical LPF 25 and the dust filter 21 and includes the gap 51 a. And this sealing structure part is provided in the outer position from the periphery of the optical LPF25 or its vicinity.

  Further, in the first embodiment, the dustproof filter receiving member 23 that is a first member that supports the dustproof filter 21 in close contact with the peripheral portion or the vicinity thereof, and the optical LPF 25 is provided in the peripheral portion or the vicinity thereof. A sealing structure is provided by a CCD case 24, which is a second member disposed so as to be in close contact with and supported in close contact with the dust-proof filter receiving member 23 (first member) at its own predetermined portion. The part is composed.

  In the camera 1 configured as described above, the dust-proof filter 21 is disposed opposite to the light-receiving surface of the image sensor 27, and the sealing space 51 formed at the periphery of the light-receiving surface of the image sensor 27 and the dust-proof filter 21 is provided. Sealing and covering the light receiving surface of the image pickup device 27 with the dustproof filter 21 prevents dust and the like from adhering to the light receiving surface of the image pickup device 27.

  In this case, with respect to dust and the like adhering to the exposed surface on the front side of the dustproof filter 21, a periodic voltage is applied to the piezoelectric element 22 disposed so as to be integrated with the peripheral portion of the dustproof filter 21. This can be removed by applying a predetermined vibration to 21.

  Here, the vibration (dust removal operation) of the dustproof filter 21 will be described.

  FIG. 7 is a front view showing only the dust filter 21 and the piezoelectric element 22 provided integrally therewith in the image pickup unit 15 of the camera 1.

  8 and 9 show changes in the state of the dustproof filter 21 and the piezoelectric element 22 when a periodic drive voltage is applied to the piezoelectric element 22 of FIG. 7, and FIG. 8 shows the line AA in FIG. FIG. 9 is a sectional view taken along line BB in FIG.

  For example, when a negative (minus ;−) voltage is applied to the piezoelectric element 22, the dust filter 21 is deformed as indicated by solid lines in FIGS. 8 and 9. When a positive (plus; +) voltage is applied to the piezoelectric element 22, the dustproof filter 21 is deformed as indicated by a broken line in FIG.

  In this case, the amplitude is substantially zero at the position of the vibration node as indicated by reference numeral 21a in FIGS. By bringing the receiving portion 23c of the dustproof filter receiving member 23 into contact with the portion corresponding to the node 21a, the dustproof filter 21 can be reliably supported without inhibiting vibration. In this state, by applying a voltage whose level changes periodically to the piezoelectric element 22, the dustproof filter 21 vibrates, and dust and the like attached to the surface of the dustproof filter 21 are removed.

  Note that the resonance frequency of the dustproof filter 21 at this time is determined by the shape, plate thickness, material, and the like of the dustproof filter 21. In the example shown in FIGS. 7 to 9 described above, a case where primary vibration is generated is shown.

  Note that FIGS. 10 to 12 show the case where the secondary vibration is generated in the dust filter 21. FIG.

  FIG. 10 is a front view showing only the dust filter 21 and the piezoelectric element 22 provided integrally therewith in the imaging unit 15 of the camera 1, as in FIG. 7.

  11 and 12 show changes in the states of the dustproof filter 21 and the piezoelectric element 22 when a voltage whose level is periodically changed to generate secondary vibrations is applied to the piezoelectric element 22. 11 is a cross-sectional view taken along line AA in FIG. 10, and FIG. 12 is a cross-sectional view taken along line BB in FIG.

  For example, when a negative (minus ;−) voltage is applied to the piezoelectric element 22, the dust filter 21 is deformed as indicated by a solid line in FIGS. 11 and 12. When a positive (plus; +) voltage is applied to the piezoelectric element 22, the dustproof filter 21 is deformed as indicated by a broken line in FIG.

  In this case, as shown by reference numerals 21a and 21b in FIGS. 10 to 12, there are two pairs of nodes in the secondary vibration. For example, by bringing the receiving portion 23c of the dustproof filter receiving member 23 into contact with the portion corresponding to the node 21a, the dustproof filter 21 can be reliably secured without impeding vibration, as in the examples shown in FIGS. Can be supported.

  Here, the system configuration of the camera 1 will be described in detail.

  As shown in FIG. 3, the system of the camera 1 includes a body unit 100 that is a camera body, and a lens unit (that is, a lens barrel) 12 that is, for example, an interchangeable lens that is an accessory device (hereinafter abbreviated as “accessory”). A recording medium 39 for recording captured image data, an external power source 70, an external strobe unit 80, and the like.

  The lens unit 12 desired by the user can be detachably mounted via a lens mount (not shown) provided on the front surface of the body unit 100.

  The recording medium 39 is an external recording medium such as various memory cards or an external HDD, and is mounted so as to be communicable with the camera body via the communication connector 35 and exchangeable.

  The external power source 70 incorporates an AC / DC converter function, and is connected between, for example, a household power outlet and a jack 37 on the camera body side via an attached connector 71 and a plug 72, so that the camera 1. Electric power necessary for the operation is supplied to the body unit 100.

  The strobe unit 80 includes a flash bulb 81, a DC / DC converter 82, a strobe control microcomputer 83, and a battery 84, and is attached to the body unit 100 via a strobe communication connector 85 so as to be communicable.

  The lens unit 12 is controlled by a lens control microcomputer (hereinafter referred to as “Lucom”) 5. The body unit 100 is controlled by a body control microcomputer (corresponding to the sequence control unit 201, hereinafter referred to as “Bucom”) 50. The Lucom 5 and Bucom 50 are electrically connected via the communication connector 6 when the lens unit 12 and the body unit 100 are combined. Lucom 5 operates in cooperation with Bucom 50 in a dependent manner.

  In the lens unit 12, a photographing lens 12a and a diaphragm 3 are provided. The photographic lens 12a is driven by a DC motor (not shown) existing in the lens driving mechanism 2. The diaphragm 3 is driven by a stepping motor (not shown) existing in the diaphragm drive mechanism 4. Lucom 5 controls each of these motors in accordance with a command from Bucom 50.

  The following structural members are disposed in the body unit 100. For example, in addition to a single-lens reflex type pentaprism 13a, main mirror 13b, eyepiece 13c, and submirror 13d as an imaging optical system, a focal plane shutter 14 on the optical axis, and the submirror (corresponding to the submirror 102) An AF sensor unit 30a for automatically measuring the distance by receiving the reflected light beam from 13d is provided.

  Further, an AF sensor driving circuit 30b for driving and controlling the AF sensor unit 30a, a mirror driving mechanism 18 for driving and controlling the main mirror 13b, a shutter charging mechanism 19 for charging springs for driving the front curtain and the rear curtain of the shutter 14, A shutter control circuit 31 for controlling the movement of the front curtain and the rear curtain, a photometric circuit 32 for performing photometric processing based on the light flux from the pentarhythm 13a, and the like are provided.

  On the optical axis, an image sensor 27 that photoelectrically converts a subject image that has passed through the optical system is provided, and the image sensor 27 is provided by a light-transmitting dustproof filter 21 that covers the light receiving surface of the image sensor 27. Is protected. A piezoelectric element 22 is attached to the periphery of the dust filter 21 as part of the vibration means that vibrates the dust filter 21 at a predetermined frequency.

  The piezoelectric element 22 has two electrodes, and the dustproof filter 21 vibrates by applying a voltage from the dustproof filter drive circuit 48 between the two electrodes. Due to this vibration, the dust adhering to the surface of the dustproof filter 21 is shaken off and removed. Thus, an electronic camera system having the basic structure of a so-called “camera with dustproof function” is configured.

  Note that a temperature measurement circuit 33 is provided in the vicinity of the dust filter 21 in order to measure the temperature around the image sensor 27.

  This camera system also includes a CCD interface circuit 34 connected to the image sensor 27, a liquid crystal monitor 36, an SDRAM 38a provided as a storage area, a flash ROM 38b, a recording medium 39, and an image processing controller 40 that performs image processing. Is provided so that an electronic recording display function can be provided together with an electronic imaging function.

  As other storage areas, a nonvolatile memory 29 made of, for example, an EEPROM is provided as a nonvolatile storage means for storing predetermined control parameters necessary for camera control, and is accessible from the Bucom 50.

  The Bucom 50 includes an operation display LCD 57 for notifying the user of the operation state of the camera by display output, and a camera operation switch (corresponding to the mode setting unit 203) 52 as selection means for selecting a shooting mode. Is provided. The camera operation switch 52 is a switch group including operation buttons necessary for operating the camera, such as a release switch, a mode change switch, and a power switch, and changes the SWRAF mode in addition to the continuous shooting mode selection switch. To select the moving object AF mode. Further, a battery 54 that is an operation power supply of the camera 1, a power supply circuit 53 a that converts and supplies the voltage of the battery 54 to a voltage required by each circuit unit of the camera system, and an input from the external power supply 70 via the jack 71. And a voltage detection circuit 53b for detecting the voltage of the battery 54 and a voltage of the battery 54, and a power supply type detection circuit 53c for detecting the type of the battery 54 (difference in power capacity). The power supply type detection circuit 53c is provided with a mechanical switch that is turned on or off according to the type of battery 54 (difference in power capacity) as an actuator, and the type of power (power) of the battery 54 is determined by determining the state of the switch. Detect the difference in capacity). The power source type detection circuit 53c and the voltage detection circuit 53b constitute the capacity determination unit 202 that determines the power capacity of the battery 54.

  Each part of the camera system configured as described above operates as follows.

  First, the image processing controller 40 controls the CCD interface circuit 34 in accordance with an instruction from the Bucom 50 to capture image data from the image sensor 27. This image data is converted into a video signal by the image processing controller 40 and output and displayed on the liquid crystal monitor 36. The user can confirm the captured image from the display image on the liquid crystal monitor 36.

  The SDRAM 38a is a memory for temporarily storing image data, and is used as a work area when image data is converted. The image data is stored in the recording medium 39 after being converted into JPEG data.

  The image sensor 27 has a light receiving surface protected by a light-transmitting dustproof filter 21. A piezoelectric element 22 for oscillating the filter surface is disposed at the periphery of the dust filter 21, and the piezoelectric element 22 is driven by the dust filter driving circuit 48 as described above.

  It is more preferable for dust prevention that the image pickup element 34 and the piezoelectric element 22 are housed integrally in a case surrounded by a frame having the dust filter 21 as one surface and indicated by a broken line.

  Normally, temperature affects the elastic modulus of glass materials and is one of the factors that change its natural frequency. Therefore, the temperature must be measured during operation and its natural frequency must be taken into account. Don't be. During operation, it is better to measure the temperature change of the dust-proof filter 21 provided to protect the front surface of the image sensor 27 where the temperature rises rapidly, and to predict the natural frequency at that time.

  Therefore, in this example, a sensor (not shown) connected to the temperature measurement circuit 33 is provided to measure the ambient temperature of the image sensor 27. The temperature measurement point of the sensor is preferably set in the vicinity of the vibration surface of the dust filter 21.

  The mirror drive mechanism 18 is a mechanism for driving the main mirror 13b to the up position and the down position. When the main mirror 13b is lowered and is in the down position, the light flux from the photographing lens 12a is on the AF sensor unit 30a side. And led to the pentaprism 13a side.

  The output from the AF sensor in the AF sensor unit 30a is transmitted to the Bucom 50 via the AF sensor driving circuit 30b, and a known distance measurement process is performed.

  The eyepiece 13c adjacent to the pentaprism 13a allows the user to see the subject, while part of the light beam that has passed through the pentaprism 13a is guided to a photosensor (not shown) in the photometry circuit 32, where it is detected. A well-known photometric process is performed based on the light quantity.

  Next, driving of the dustproof filter 21 will be described based on the circuit of the dustproof filter driving circuit 48 shown in FIG. 13 and the time chart shown in FIG.

  The dustproof filter driving circuit 48 has the circuit configuration of FIG. 13 and has the same length as follows based on the waveform signals Sig1 to Sig4 shown in the time chart of FIG.

  The dustproof filter driving circuit 48 includes an N-ary counter 41, a 1/2 frequency divider 42, an inverter 43, a plurality of MOS transistors (Q00.Q01.Q02) 44a, 44b, 44c, a transformer 45, and a resistor (R00) 46. Has been.

  An on / off switching operation of the transistor (Q01) 44b and the transistor (Q02) 44c connected to the primary side of the transformer 45 generates a signal Sig4 having a predetermined period on the secondary side of the transformer 45. Based on this signal Sig4, the piezoelectric element 22 is driven to resonate the dust filter 21.

  The Bucom 50 has two IO ports P_PwCont and IO port D_NCnt provided as control ports, and controls the dustproof filter drive circuit 48 using the internal clock generator 55 as follows. The clock generator 55 outputs a pulse signal (referred to as a basic clock signal) having a frequency sufficiently higher than the frequency of the signal applied to the piezoelectric element 22. This basic clock signal is Sig 1 and is input to the N-ary counter 41.

  The N-ary counter 41 counts the pulses of the input basic clock signal Sig1, and outputs a count end pulse signal every time the count value reaches a predetermined value “N”. That is, the basic clock signal Sig1 is divided by 1 / N. The pulse signal after the frequency division is Sig2.

  The pulse signal Sig2 after frequency division does not have a high-level and low-level duty ratio of 1: 1. Therefore, the pulse signal Sig2 after the frequency division is passed through the 1/2 frequency dividing circuit 42 to convert the duty ratio to 1: 1. Note that the converted pulse signal is Sig3.

  In the high level period of the converted pulse signal Sig3, the MOS transistor (Q01) 44b is turned on. On the other hand, the pulse signal Sig3 is applied to the transistor (Q02) 44c via the inverter 43. Therefore, the transistor (Q02) 44c is turned on in the low level period of the pulse signal Sig3. When the transistor (Q01) 44b and the transistor (Q02) 44c connected to the primary side of the transformer 45 are alternately turned on, a signal having a cycle such as Sig4 is generated on the secondary side of the transformer 45.

  The winding ratio of the transformer 45 is determined from the output voltage of the power supply circuit 53 a and the voltage necessary for driving the piezoelectric element 22. The resistor (R00) 46 is provided to restrict an excessive current from flowing through the transformer 45.

  When driving the piezoelectric element 22, the transistor (Q00) 44a must be in an on state, and a voltage must be applied from the power supply circuit 53a to the center tap of the transformer 45. The transistor (Q00) 44a is ON / OFF controlled by the output of the IO port P_PwCont. The set value “N” of the N-ary counter 41 can be set by the output of the IO port D_NCnt. The Bucom 50 can arbitrarily change the frequency of the drive signal for the piezoelectric element 22 by appropriately controlling the set value “N”.

The frequency of the drive signal for the piezoelectric element 22 is expressed by the following equation.
fdrv = fpls / 2N
N is a set value for the N-ary counter 41, fpls is the frequency of the output signal of the clock generator 55, and fdrv is the frequency of the signal applied to the piezoelectric element 22.
The calculation based on the above equation is performed by the CPU (control means) of the Bucom 50.

  Before describing the flowchart of the camera sequence procedure, the power capacity of the battery will be described.

  FIG. 15 shows a state where one of two types of batteries having different power capacities is attached to the camera body 11 as the battery 24.

  That is, a charge type battery (for example, Li ion battery) 111 having a small power capacity and a charge type battery (for example, Li ion battery) 112 having a large power capacity can be mounted on the battery mounting portion 113 as the battery 24. Yes.

A switch unit 114 for determining which of the batteries 111 and 112 is mounted is provided as an actuator of the power supply type detection circuit 53C. When the battery 112 having a large capacity is mounted, the convex portion 112a of the battery 112 is switched. The mechanical switch of the unit 114 is pressed and turned on, and an electric signal indicating that the battery 112 is attached is sent to the Bucom 50. When the battery 111 having a small capacity is attached, the mechanical switch of the switch unit 114 is not pressed (off state). At this time, the attachment of the battery 111 itself can be grasped by detecting the battery voltage by the voltage detection circuit 53b.
Based on the output of the switch unit 114 and the output of the voltage detection circuit 53b, the Bucom 50 determines which of the batteries 111 and 112 is installed, that is, whether the power capacity of the battery 54 is greater than or less than a predetermined value. It has a discriminating means (corresponding to the capacity discriminating unit 202 in FIG. 1).

  FIG. 16 shows the cumulative power consumption during the photographing operation, particularly the change in the cumulative power consumption when the dust removal operation due to the dust filter 21 being vibrated is performed while the main mirror 13b is being mirrored up. In the figure, the horizontal axis represents time, and the vertical axis represents power consumption (power supplied from the battery 54). The time indicated as “start” corresponds to the development sequence start timing (up start timing of the main mirror 13b).

  At the start of the development sequence, three mechatronic controls are simultaneously executed: driving of the photographing optical system 12a by the lens driving mechanism 2, driving of the diaphragm 3 by the diaphragm driving mechanism 4, and driving of the main mirror 13b by the mirror driving mechanism 18. As described above, the lens drive rush power, the aperture drive rush power, and the mirror drive rush power are superimposed. Each inrush power corresponds to the power at the start of starting each motor that requires a large current.

  Here, the dust filter driving power is the power consumption of the dust filter driving circuit 48. When the dust removal operation is performed in parallel with the mirror drive, the power consumption of the dustproof filter drive circuit 48 is also superimposed.

  The driving power of other devices indicates power consumption of other devices excluding the lens driving mechanism 2, the aperture driving mechanism 4, the mirror driving mechanism 18, and the dust filter driving circuit 48, and is substantially constant.

  The rated power capacity of the Li ion battery 111 having a small power capacity and the rated power capacity of the Li ion battery 112 having a large capacity are shown by broken lines in FIG. That is, in order to operate the dustproof filter drive circuit 48 in parallel with the mirror drive mechanism 18, it is necessary to use the Li ion battery 112 having a large power capacity. When the Li ion battery 111 having a small power capacity is used, the dustproof filter drive circuit 48 cannot be operated in parallel with the mirror drive mechanism 18.

  The Bucom 50 has, as main functions, a first control function for operating the piezoelectric element 22 that is a vibrating means at a timing parallel to the driving of the mirror driving mechanism 18 and a piezoelectric at a timing before the driving of the mirror driving mechanism 18. A second control function is provided to operate the element 22 and end the operation, and selectively execute one of these control functions.

The control executed by the Bucom 50 is shown by the flowchart of FIG. 17 and the subsequent FIG.
The control of the Bucom 50 is started when a power switch (not shown) of the camera 1 is turned on.

  First, in # 000, as an initial setting operation at the time of starting the camera system, power supply from the power supply circuit 53a to each circuit unit in the camera system is started, and initial setting of each circuit unit is performed.

  In # 001, data related to the drive time (Tosc) and drive frequency (resonance frequency: Nosc) for the dust filter 21 is read from a predetermined area of the EEPROM 29.

  In # 002, a signal of the drive frequency (Nosc) is output from the output port D_NCnt of the Bucom 50 according to the read data. This output is supplied to the N-ary counter 41 of the dustproof filter driving circuit 48.

  In # 003, vibration (dust removal operation) of the dustproof filter 21 due to the operation of the piezoelectric element 22 is started. That is, by setting the output of the IO port P_PwCont to a high level, the piezoelectric element 22 is driven at a predetermined driving frequency (Nosc) to vibrate the dustproof filter 21, and dust attached to the dustproof filter 21 is caused by the vibration. It will be paid off. That is, the dust removal operation is started. As a result, during this period when the camera 1 is not yet used for shooting, the user can automatically remove dust adhering to the dustproof filter 21 without intending anything.

  In # 004, while the vibration of the dustproof filter 21 is continued, standby is performed for a predetermined time (Tosc) based on the read data.

  After the elapse of a predetermined time (Tosc), in # 005, the output of the IO port P_PwCont is set to a low level, thereby stopping the driving of the piezoelectric element 22, stopping the vibration of the dustproof filter 21, and stopping the dust removing operation. .

Subsequent # 006 to # 039 are steps periodically executed.
In # 006, an attachment / detachment detection operation for detecting the state of the lens unit 12 is executed by communication with Lucom5.

  In # 007, when it is detected that the lens unit 12 is attached to the body unit 100, the process proceeds to # 010, and the control flag F_Lens is set to “1”. In # 008, when it is detected that the lens unit 12 is detached from the body unit 100, the process proceeds to # 009, and the control flag F_Lens is set to “0”. Thereafter, the process proceeds to # 014.

  The control flag F_Lens is “1” when the lens unit 12 is attached to the body unit 100 and “0” when the lens unit 12 is removed.

  Here, since the lens unit 12 is mounted, the dust removal operation is performed in the same manner as described above in # 011 to # 013. That is, the dust removal operation is started by setting the output of the IO port P_PwCont to a high level. The piezoelectric element 22 vibrates the dust-proof filter 21 at a predetermined frequency (Nosc) and shakes off dust attached to the dust-proof filter 21 (# 011).

  The dust filter 21 continues to vibrate for a predetermined time (Tosc) (# 012). After the predetermined time (Tosc) has elapsed, the output of the IO port P_PwCont is set to a low level to perform the dust removal operation. Stop (# 013). That is, during this period when the camera 1 is not yet used for photographing, the user can automatically remove the dust attached to the dustproof filter 21 without intending anything.

  As described above, during the period in which the lens unit 12 is not attached to the body unit 100, since there is a high possibility that dust usually adheres to each lens, the dustproof filter 21, etc., the timing at which the attachment of the lens unit 12 is detected. It is desirable to carry out the operation of dusting off with. In addition, since there is a high possibility that external air circulates inside the camera and dust adheres when the lens is exchanged, it is meaningful to perform the dust removal operation even when this lens is exchanged.

  In # 014, whether or not a 1st release switch (not shown), which is one of the camera operation switches, has been operated is determined based on the on / off state of the 1st release switch. If the first release switch has not been turned on for a predetermined time or longer, the process proceeds to # 040, where the power switch is turned off to end the process, for example, the sleep state.

  When the 1st release switch is turned on, the luminance information of the subject is obtained from the photometry circuit 32 in # 016. From this information, the exposure time (Tv value) of the image sensor 27 and the aperture setting value (Av value) of the lens unit 12 are calculated.

  In # 017, it is determined whether or not the vibration completion flag is set once while the first release switch is on. This flag serves as an indicator of whether or not the dustproof filter 21 has been vibrated once while the first release switch is on (in the loop of # 006 → # 026 → # 040 → # 006), and is set at # 019 described later. It is cleared at # 039 described later. It is also cleared by the initial setting operation of # 000.

  When the flag is set, the dustproof filter 21 has already been vibrated once while the 1st release switch is on, so here the process proceeds to # 021 without performing vibration and is cleared. In this case, the process proceeds to # 018 to perform vibration.

  In # 018, the power capacity of the battery 54 is determined based on the concept described in FIG. 15 and FIG. When a battery with a small power capacity is installed as the battery 54, the process proceeds to # 019 to set the vibration-existing flag once while the 1st release switch is on in order to perform the dust removal operation at the current timing. The dust removal operation is started at # 020. When a battery having a large power capacity is attached as the battery 54, the process directly proceeds to # 021.

  In # 021, detection data of the AF sensor unit 30a is obtained via the AF sensor drive circuit 30b. Based on this data, the amount of focus shift is calculated.

  In # 022, the power capacity of the battery 54 is determined again. When a battery with a small capacity is attached as the battery 54, the dust removal operation is stopped by setting the output of the IO port P_PwCont to a low level in # 023, and the process proceeds to # 024. When a battery having a large power capacity is attached as the battery 54, the process directly proceeds to # 024.

  In # 024, the state of the control flag F_Lens is determined. If the control flag F_Lens is “0”, it means that the lens unit 12 does not exist, and therefore the next photographing operation after # 025 cannot be executed. Therefore, in this case, the process proceeds to # 040, where the power switch is turned off to end the process, for example, to enter a sleep state. If the control flag F_Lens is “1”, the process proceeds to the next # 025.

  In # 025, the amount of focus shift is transmitted to Lucom 5, and drive control of the photographing lens 12a based on this amount of shift is commanded.

  In # 026, it is determined whether or not a 2nd release switch (not shown) which is one of the camera operation switches 52 is turned on. When the 2nd release switch is on, the process proceeds to # 027. When the 2nd release switch is off, the process proceeds to # 040. When the power switch is turned off, the termination process is performed, for example, a sleep state is entered.

  In # 027, the power capacity of the battery 54 is determined again. When a battery having a small power capacity is attached as the battery 54, the process proceeds to # 029 as it is, based on the determination that the dust removal operation is unnecessary (the dust removal operation has already been completed) at this timing. When a battery having a large power capacity is attached as the battery 54, the process proceeds to # 028 based on the determination that the dust removal operation is necessary at this timing.

  In # 028, the dust removal operation for removing dust prior to the photographing operation is started by setting the output of the IO port P_PwCont to a high level.

  From # 029 immediately after the start of the dust removal operation, first, the Av value is transmitted to the Lucom 5, and the driving of the diaphragm 3 is instructed. At # 030, the main mirror 13b is moved to the up position. At # 031, the shutter 14 starts the leading curtain travel and performs open control. At # 032, the image processing controller 40 is instructed to execute an imaging operation. FIG. 19 shows an imaging operation routine, which will be described later.

  When exposure (imaging) to the image sensor 27 is completed for the time indicated by the Tv value, the trailing curtain travel of the shutter 14 is started and closed control is performed in # 033.

  In # 034, the power capacity of the battery 54 is determined again. When a battery with a small power capacity is attached as the battery 54, the dust removal operation is not performed at this timing (since it has already been performed), the process proceeds to # 036. When a battery having a large power capacity is attached as the battery 54, the dust removal operation is performed at this timing, and the process proceeds to # 035. In # 035, the dust removal operation is stopped by setting the output of the IO port P_PwCont to a low level.

  Note that during the imaging operation of # 032, the electronic imaging operation for a time corresponding to the time set for exposure (exposure time) is controlled as usual (details omitted).

  In this way, even during the imaging operation, the dust attached to the dustproof filter 21 can be automatically removed without any intention of the user.

  Thereafter, at # 036, the main mirror 13b is driven to the down position and the shutter 14 is charged.

  In step # 037, the controller 3 instructs Lucom 5 to return the diaphragm 3 to the open position. In # 038, the image processing controller 40 is instructed to record the captured image data on the recording medium 39. When the recording operation of the image data is finished, in # 039, the vibration completion flag is cleared once while the first release switch set in # 019 is turned on, and the process proceeds to # 006 again, and the same series of processing is performed. repeat.

  In the last # 040, the process proceeds to # 040, and the end process (sleep or the like) is performed by turning off the power switch. Then, the operating state is suspended.

Here, the routine of the imaging operation shown in FIG. 19 will be described.
In the dust removal operation of the camera 1, when the imaging operation is set to “long time” such as 2 to 3 seconds, the piezoelectric element 22 is driven for dust removal for a predetermined time (for example, 20 ms), and thereafter, the driving of the piezoelectric element 22 is controlled to end.

  That is, during the imaging operation, a comparison determination is performed between the time set for exposure (exposure time) and the limited predetermined time (200 ms), and the predetermined time is preferentially determined. Thus, the dust removal operation time is appropriately controlled. Therefore, even if an exposure time longer than the predetermined time is set, the dust removal operation is controlled to stop in the middle.

  First, at # 050, the Bucom 50 instructs the shutter control circuit 31, the CCD interface circuit 34, and the like to start the imaging operation at the set exposure time (including the long time).

  In step # 051, the Bucom 50 determines the elapse of exposure second time related to the imaging operation. Here, if the exposure time has already passed, the process proceeds to # 033 of the main routine.

  If the exposure time is a long second time and does not yet elapse, the power capacity of the battery 54 is determined at # 052. If a battery with a small power capacity is attached as the battery 54, the dust removal operation is not performed here, and the process returns to # 051. When a battery having a large power capacity is attached as the battery 54, the dust removal operation is already in progress at this time, so in # 053, a predetermined time (200 ms) after the dust removal operation is started. It is determined whether or not elapses. If it has not yet elapsed, the process returns to # 051 to continue the dust removal operation. If the predetermined time has elapsed, in # 054, even if the exposure time (long time) has not been reached, the output of the IO port P_PwCont is set to a low level to stop the dust removal operation. And it returns to # 051.

  As described above, in the first embodiment, the dust removal operation by the vibration of the dustproof filter 21 is performed at the same timing as the driving of the main mirror 13b that is up before the imaging operation of the image sensor 27 and goes down after the imaging operation. There is a first control to be executed and a second control for starting the dust removal operation at a timing before driving the main mirror 13b and ending the dust removal operation, and the power capacity of the mounted battery 54 is The first control is executed if it is greater than or equal to a predetermined value, and the second control is executed if the power capacity of the attached battery 54 is less than a predetermined value.

  That is, when the power capacity of the battery 54 is large, the dust removal operation is started immediately before the main mirror 13b starts mirror-up, and the dust removal operation is continued until imaging including mirror-up, which is closer to the imaging timing. The dust removal operation at the timing becomes possible. Thereby, the bad influence on the picked-up image by dust can be eliminated reliably.

  When the power capacity of the battery 54 is small, the dust removal operation is started at the timing before the mirror up start of the main mirror 13b and the dust removal operation is finished. Even if a large amount of power is required for the dust removal operation by vibration, a reliable and good dust removal operation can always be performed without applying a great load to the battery 54. Since a large load is not applied to the battery 54, it is possible to avoid problems such as troubles in the operation of the camera.

  Specifically, the timing of the main mirror 13b before starting the mirror up is during the focus detection operation, and there are the following three advantages as the dust removal operation in parallel with the focus detection operation.

  (1) At the timing of the focus detection operation, since many other devices are not operating, there is a power margin.

  (2) In the continuous shooting mode, focus detection is performed after the main mirror 13b is moved down, and the lens driving operation is subsequently performed after the focus detection. Therefore, in order to prevent the dust removal operation from causing a time lag as much as possible, focus detection and It is better to run in parallel.

  (3) Especially when the subject is dark, it takes time for the charge accumulation time of the AF sensor in the AF sensor unit 30a, which is suitable as a timing for performing the dust removal operation.

  In addition to the focus detection operation, the dust removal operation may be performed in parallel with the photometry operation of the photometry circuit 32 (# 016 in FIG. 18).

[2] A second embodiment will be described.
In the second embodiment, it is determined whether or not the shooting mode selected by operating the camera operation switch 52 is a moving body mode suitable for shooting a moving subject, for example, a moving body AF mode. The dust removal operation is started at the timing before driving 13b and the dust removal operation is ended (second control). If it is not the moving object AF mode (shooting mode suitable for a stationary subject), the dust removal operation is executed at a timing parallel to the driving of the main mirror 13b that is up before the image pickup operation of the image pickup device 27 and goes down after the image pickup operation (first) Control).

  As already described, the moving object AF mode is a mode in which a so-called moving object prediction technique for focusing on a moving subject is mounted. Generally, in the moving object AF mode, as described with reference to FIG. 1, the lens driving operation is performed in parallel with the mirror up operation in order to shorten the time lag. In the moving AF mode in which the lens is also driven while the mirror is up, no dust removal operation is performed during the mirror up to reduce the battery load.

  Of the control of the Bucom 50 in the second embodiment, the part different from the first embodiment is shown in the flowchart of FIG. 20 (the flowchart following FIG. 17). That is, instead of # 022, # 027, and # 034 for determining the power capacity of the battery 54, # 022a, # 027a, and # 034a for determining whether or not the moving body AF mode is set are employed.

  Also, FIG. 21 shows the routine of the imaging operation in # 032, and instead of # 052 for determining the power capacity of the battery 54, # 052a for determining whether or not the moving object AF mode is in effect.

  Other configurations and operations are the same as those in the first embodiment. Therefore, the description is omitted.

  Note that the processing of FIG. 20 shows an example of the single shooting mode of single frame shooting, but it may be combined with the continuous shooting mode. In this case, as described with reference to FIG. 1, the main mirror 13b is lowered after shooting one frame, and then the AF operation (AF sensor integration & AF calculation) is performed. The main mirror 13b is raised to enter, and when the up is completed, the next frame exposure operation is started. The lens driving based on the AF result (based on the moving object prediction technique) is performed in parallel with the mirror up operation. This is a repetition.

  In such a continuous shooting sequence of the camera, the dust removal operation may be performed so that the operation is completed before the mirror-up drive.

  The present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine the component covering different embodiment suitably.

The figure for demonstrating the concept of the principal part of 1st Embodiment. FIG. 3 is a perspective view schematically showing an internal structure of a part of the camera according to the first embodiment by cutting. FIG. 2 is a block diagram showing an electrical configuration of the camera of the first embodiment. The perspective view which decomposes | disassembles and shows the imaging unit in 1st Embodiment. The perspective view which cut | disconnects and shows a part of assembly state of the imaging unit in 1st Embodiment. Sectional drawing which follows the cut surface of FIG. The figure which shows the structure of the dustproof filter in 1st Embodiment. The figure which shows the cross section which follows the AA line of FIG. The figure which shows the cross section which follows the BB line of FIG. The figure which shows the structure of a dustproof filter at the time of generating a secondary vibration in the dustproof filter in 1st Embodiment. The figure which shows the cross section which follows the AA line of FIG. The figure which shows the cross section which follows the BB line of FIG. The block diagram of the dustproof filter drive circuit in 1st Embodiment. The signal waveform diagram of each part of the dustproof filter drive circuit in a 1st embodiment. The figure which shows a mode that two types of batteries in 1st Embodiment are mounted | worn. The figure which shows the change of the integrated power consumption of the camera in 1st Embodiment. The flowchart for demonstrating the operation | movement of Bucom in 1st Embodiment. The flowchart following FIG. The flowchart which shows the imaging operation in FIG. The flowchart for demonstrating the operation | movement of Bucom in 2nd Embodiment. The flowchart which shows the imaging operation in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 101 ... Main mirror, 103 ... Shutter, 104 ... Image sensor, 105 ... Dustproof filter, 200 ... Dustproof filter drive part, 201 ... Sequence control part, 202 ... Capacity determination part, 203 ... Mode setting part, 1 ... Camera, 11 ... Camera body 12, lens barrel 12 a photographing optical system 13 finder device 14 shutter 15 imaging unit 18 mirror drive mechanism 50 Bucom 52 52 camera operation switch (selection means) 53a ... power supply circuit, 53b ... voltage detection circuit, 54 ... battery (power supply)

Claims (6)

In an electronic imaging apparatus provided with an imaging element,
A translucent member provided on the light receiving portion of the imaging element;
Vibration means for vibrating the translucent member;
Control means for controlling the timing of operation of the vibration means;
An electronic imaging apparatus comprising: A mirror that is up before the image pickup operation of the image pickup device and goes down after the image pickup operation; and a mirror driving means for driving the mirror;
The control means operates the excitation means at a timing prior to driving the mirror driving means and performs the first control for operating the excitation means at a timing parallel to the driving of the mirror driving means. The electronic imaging apparatus according to claim 1, wherein any one of the second controls to be ended is selectively executed. It further comprises a discriminating means for discriminating the capacity of the battery mounted as the power source of the device,
The control means executes the first control when the capacity determined by the determination means is greater than or equal to a predetermined value, and executes the second control when the capacity determined by the determination means is less than a predetermined value. The electronic imaging apparatus according to claim 2. A selection means for selecting a shooting mode;
The control unit performs the second control when the shooting mode selected by the selection unit is a moving body mode suitable for shooting a moving subject, and the shooting mode selected by the selection unit is not the moving body mode. The electronic imaging apparatus according to claim 2, wherein the first control is executed in some cases. An imaging optical system that projects an optical image of a subject onto the imaging element; and a focus detection unit that performs focus detection of the imaging optical system;
The electronic imaging apparatus according to claim 2, wherein the timing before driving the mirror driving unit is at least during the operation of the focus detection unit. The electronic imaging apparatus according to claim 1, wherein the translucent member is a translucent dustproof filter provided so as to cover a light receiving portion of the imaging element.

Images