JP4098120B2 - Electronic imaging device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electronic imaging apparatus, and more particularly, to an electronic imaging apparatus with a dustproof function that can remove dust attached to components such as a camera system.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as an example of a technique related to a dustproof function of an optical device, a technique has been proposed in which dust attached to the dustproof glass is removed by vibrating a protective glass (dustproof glass) that protects an image sensor. For example, there exists what was disclosed by Unexamined-Japanese-Patent No. 2002-204379, and the piezoelectric element is used for this as a means to vibrate dust-proof glass. This piezoelectric element expands and contracts in response to an applied voltage, and vibrates the attached dustproof glass at a predetermined cycle. Japanese Patent Application No. 2002-142703 discloses that a dust removal operation is performed when a photographing lens is replaced.
[0003]
[Problems to be solved by the invention]
There are various situations in which dust adheres to the dust-proof glass. When the photographic lens is replaced, the mirror box may be exposed and dust may enter from the outside of the camera and adhere to the dust-proof glass. There is a higher possibility that dust will adhere to the dust-proof glass when the shutter is in the OPEN state without attaching the interchangeable lens (lens unit). Even in such a situation, it seems that there are few problems if the shutter speed is high.
[0004]
On the other hand, with improvement in performance of the image sensor, some users attach a camera to the telescope and take astronomical photographs. In astrophotography, the shutter speed is long because the subject brightness is low. Therefore, there is a possibility that dust may adhere to the shutter OPEN. In addition, telescopes are often larger than interchangeable lenses for cameras, and their sealing performance is low. Therefore, the possibility of contact between the dust-containing air and the dust-proof glass is increased.
[0005]
The above-mentioned prior art does not show a countermeasure for the problem of dust adhering to the shutter OPEN during such a long exposure time.
[0006]
The present invention has been made paying attention to such problems, and the object of the present invention is to reduce image quality by performing an appropriate dust removal operation, for example, in an imaging operation in which long exposure is performed. It is an object of the present invention to provide an electronic imaging apparatus that does not incur and eliminates unnecessary power consumption.
[0007]
[Means for Solving the Problems]
  To achieve the above objective,An electronic imaging apparatus according to a first aspect of the present invention includes an imaging lens, an imaging element that converts an image of the imaging lens into an electrical signal, and an optical that prevents adhesion of dust or the like to the photoelectric conversion surface of the imaging element. And a control means for performing a dust removal operation by vibrating the optical element, and an operation switch for instructing the dust removal operation, and the control means performs a dust removal operation in response to an operation of the operation switch. In the case where the optical element is vibrated at the resonance frequency of the optical element, and the long-exposure shooting operation is set and the dust removal operation is performed during the exposure period, the resonance frequency of the optical element is used. The optical element is vibrated at a shifted frequency.
[0008]
  Also,An electronic imaging apparatus according to a second aspect of the present invention includes an interchangeable imaging lens, an imaging element that converts an image of the imaging lens into an electrical signal, and adhesion of dust and the like to the photoelectric conversion surface of the imaging element. And an optical element for preventing dust and a control means for performing a dust removal operation by vibrating the optical element. When the dust removal operation is performed when the photographing lens is replaced, the control means When the optical element is vibrated at a resonance frequency and a long-time exposure photographing operation is set and a dust removing operation is performed during the exposure period, the optical element is vibrated at a frequency deviated from the resonance frequency of the optical element. .
[0009]
  Also,An electronic imaging apparatus according to a third aspect of the present invention includes a photographing lens, an imaging element that converts an image of the photographing lens into an electrical signal, and an optical that prevents adhesion of dust or the like to the photoelectric conversion surface of the imaging element. And a control means for performing a dust removal operation by vibrating the optical element, and an operation switch for instructing the dust removal operation, and the control means performs a dust removal operation in response to an operation of the operation switch. In the case where the optical element is continuously vibrated, the optical element is intermittently vibrated when the long-time exposure photographing operation is set and the dust removing operation is performed during the exposure period..
[0010]
  Also,According to a fourth aspect of the present invention, there is provided an electronic imaging device including an interchangeable imaging lens, an imaging element that converts an image of the imaging lens into an electrical signal, and adhesion of dust or the like to the photoelectric conversion surface of the imaging element. And an optical element for preventing dust and a control means for vibrating the optical element to perform a dust removing operation. When the dust removing operation is performed when the photographing lens is replaced, the control means When the long-time exposure shooting operation is set and the dust removal operation is performed during the exposure period, the optical element is vibrated intermittently..
[0011]
  An electronic imaging apparatus according to a fifth aspect of the present invention is the electronic imaging apparatus according to any one of the first to fourth aspects, wherein the control means sets a bulb photographing operation as the long-time exposure photographing operation. Then, the dust removal operation is performed during the exposure period..
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0018]
FIG. 1 is a partially cutaway perspective view showing a schematic configuration of an embodiment when the present invention is applied to a digital camera.
[0019]
That is, FIG. 1 is a perspective view schematically showing an internal configuration of a part of the camera body cut away.
[0020]
The camera 1 according to the present embodiment includes a camera main body 11 and a lens unit 12 that are separately configured, and both the camera main body 11 and the lens unit 12 are configured to be detachable from each other. It is.
[0021]
The lens unit 12 includes a photographing optical system 12a including a plurality of lenses and their driving mechanisms.
[0022]
The photographing optical system 12a transmits a light beam from the subject so that an image of the subject formed by the subject light beam is formed at a predetermined position (on a photoelectric conversion surface of an image sensor described later). For example, it is composed of a plurality of optical lenses.
[0023]
The lens unit 12 is disposed so as to protrude toward the front surface of the camera body 11. In addition, the camera body 11 includes various components and the like, and is an imaging optical device that is a connecting member for detachably disposing the lens unit 12 that holds the imaging optical system 12a. This is a so-called single-lens reflex camera having the system mounting portion 11a provided on the front surface thereof.
[0024]
That is, an exposure opening having a predetermined aperture capable of guiding the subject light flux into the camera body 11 is formed at a substantially central part on the front side of the camera body 11, and the periphery of the exposure opening A photographing optical system mounting portion 11a is formed in the portion.
[0025]
In addition to the above-described photographing optical system mounting portion 11a being disposed on the front surface of the camera main body 11, various operation members for operating the camera main body 11 at predetermined positions such as an upper surface and a back surface. For example, a release button 17 or the like for generating an instruction signal or the like for starting the photographing operation is provided.
[0026]
Inside the camera body 11, various components, for example, a finder device 13 that constitutes a so-called observation optical system, and a shutter mechanism that controls the irradiation time of the subject luminous flux on the photoelectric conversion surface of the image sensor, etc. The shutter unit 14 provided, an image pickup device (not shown) that obtains an image signal corresponding to the subject image, and a predetermined position on the front surface side of the photoelectric conversion surface of the image pickup device, dust or the like on the photoelectric conversion surface A plurality of circuits including an image pickup unit 15 including a dustproof filter (also referred to as dustproof glass) 21 which is a dustproof member for preventing adhesion of the liquid and a main circuit board 16 on which various electrical members constituting the electrical circuit are mounted. Substrates (only the main circuit board 16 is illustrated) and the like are respectively disposed at predetermined positions.
[0027]
The finder device 13 includes a quick return mirror 13b configured to bend the optical axis of a subject light beam that has passed through the photographing optical system 12a and guide the light beam toward the observation optical system, and a light beam emitted from the quick return mirror 13b. A pentaprism 13a that receives 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.
[0028]
The quick return mirror 13b is configured to be movable between a position retracted from the optical axis of the photographing optical system 12a and a predetermined position on the optical axis, and in a normal state, on the optical axis of the photographing optical system 12a. The optical axis is arranged with a predetermined angle, for example, an angle of 45 degrees.
[0029]
As a result, the subject luminous flux transmitted through the photographing optical system 12a is bent by the quick return mirror 13b when the camera 1 is in a normal state, and the pentaprism is arranged above the quick return mirror 13b. Reflected toward the side 13a.
[0030]
On the other hand, while the camera 1 is performing a photographing operation, the quick return mirror 13b moves to a predetermined position retracted from the optical axis of the photographing optical system 12a. Guided to the element side.
[0031]
The shutter unit 14 may be the same as that generally used in conventional cameras, such as a focal plane type shutter mechanism and its drive circuit.
[0032]
FIG. 2 is a block diagram showing the system configuration of the camera according to one embodiment of the present invention.
[0033]
That is, the camera system according to this embodiment mainly includes a camera body 11 and a lens unit 12 as an interchangeable lens, and a desired lens unit 12 is detachably attached to the front surface of the camera body 11. Has been.
[0034]
The lens unit 12 is controlled by a lens control microcomputer (hereinafter referred to as “Lucom”) 205.
[0035]
The camera body 11 is controlled by a body control microcomputer (hereinafter referred to as Bucom) 150.
[0036]
Note that the Lucom 205 and Bucom 150 are electrically connected to each other via the communication connector 206 when they are combined.
[0037]
In this case, the Lucom 205 operates as a camera system in cooperation with the Bucom 150 in a dependent manner.
[0038]
In the lens unit 12, a photographing optical system 12a and a diaphragm 203 are provided.
[0039]
The photographing optical system 12a is driven by a DC motor (not shown) in the lens driving mechanism 202.
[0040]
The diaphragm 203 is driven by a stepping motor (not shown) in the diaphragm drive mechanism 204.
[0041]
The Lucom 205 controls each of these motors according to a command from the Bucom 150.
[0042]
In the camera body 11, the following components are arranged as shown.
[0043]
For example, a single-lens reflex system component (penta prism 13a, quick return mirror 13b, eyepiece 13c, submirror 114) as an optical system, a focal plane shutter 115 on the optical axis, and reflection from the submirror 14 An AF sensor unit 116 for receiving the light beam and automatically measuring the distance is provided.
[0044]
Further, an AF sensor driving circuit 117 for driving and controlling the AF sensor unit 116, a mirror driving mechanism 118 for driving and controlling the quick return mirror 13b, and a spring force for driving the front curtain and the rear curtain of the shutter 115 are provided. A shutter charge mechanism 119 for charging, a shutter control circuit 120 for controlling the movement of the front curtain and the rear curtain, and a photometric circuit 121 for performing photometric processing based on the light flux from the pentaprism 13a are provided.
[0045]
On the optical axis, an image sensor 27 for photoelectrically converting a subject image that has passed through the optical system is provided as a photoelectric converter.
[0046]
In this case, the image sensor 27 is protected by a dustproof filter 21 made of a transparent glass member as an optical element disposed between the image sensor 27 and the photographing optical system 12a.
[0047]
For example, a piezoelectric element 22 is attached to the peripheral portion of the dust filter 21 as a part of the vibration means that vibrates the dust filter 21 at a predetermined frequency.
[0048]
The piezoelectric element 22 has two electrodes. The piezoelectric element 22 vibrates the dust-proof filter 21 by the dust-proof filter driving circuit 140 as a part of the vibration means, and the dust adhered to the glass surface. It is comprised so that can be removed.
[0049]
Note that a temperature measurement circuit 133 is provided in the vicinity of the dust filter 21 in order to measure the temperature around the image sensor 27.
[0050]
This camera system also includes an interface circuit 123 connected to the image sensor 27, a liquid crystal monitor 124, an SDRAM 125 provided as a storage area, a flash ROM 126, a recording medium 127, and the like, and an image processing controller that performs image processing. 128, and an electronic image display function as well as an electronic recording display function can be provided.
[0051]
As other storage areas, for example, a nonvolatile memory 129 made of an EEPROM is provided so as to be accessible from the Bucom 150 as nonvolatile storage means for storing predetermined control parameters necessary for camera control.
[0052]
In addition, the Bucom 150 is provided with an operation display LCD 151 and a camera operation switch (SW) 152 for notifying the user of the operation state of the camera by display output.
[0053]
The camera operation SW 152 is a switch group including operation buttons necessary for operating the camera, such as a release SW, a mode change SW, and a power SW.
[0054]
Furthermore, a battery 154 as a power source and a power circuit 153 that converts the voltage of the power source into a voltage required by each circuit unit constituting the camera system are provided.
[0055]
Next, the operation of the camera system configured as described above will be described. First, the image processing controller 128 captures image data from the image sensor 27 by controlling the interface circuit 123 in accordance with an instruction from the Bucom 150.
[0056]
This image data is converted into a video signal by the image processing controller 128 and output and displayed on the liquid crystal monitor 124.
[0057]
The user can confirm the captured image from the display image on the liquid crystal monitor 124.
[0058]
The SDRAM 125 is a memory for temporarily storing image data, and is used as a work area when image data is converted.
[0059]
The image data is set to be stored in the recording medium 127 after being converted into JPEG data.
[0060]
The image sensor 27 is protected by the dustproof filter 21 made of a transparent glass member as described above.
[0061]
A piezoelectric element 22 for oscillating the glass surface is disposed at the peripheral portion of the dust filter 21, and this piezoelectric element 22 can be used as a driving means for the piezoelectric element 22 as will be described in detail later. It is driven by a working dustproof filter driving circuit 140.
[0062]
It is more preferable for dust prevention that the image pickup element 27 and the piezoelectric element 22 are integrally housed in a case having the dust filter 21 as one surface and surrounded by a frame as shown by a broken line.
[0063]
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 to take into account the change in natural frequency. Don't be.
[0064]
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 during operation, and to predict the natural frequency at that time.
[0065]
Therefore, in this example, a sensor (not shown) connected to the temperature measurement circuit 133 is provided to measure the ambient temperature of the image sensor 27.
[0066]
The temperature measurement point of the sensor is preferably set in the vicinity of the vibration surface of the dust filter 21.
[0067]
The mirror drive mechanism 118 is a mechanism for driving the quick return mirror 13b to the UP position and the DOWN position. When the quick return mirror 13b is at the DOWN position, the light flux from the photographing optical system 12a is on the AF sensor unit 116 side. And led to the pentaprism 13a side.
[0068]
The output from the AF sensor in the AF sensor unit 116 is transmitted to the Bucom 150 via the AF sensor driving circuit 117, and a known distance measurement process is performed.
[0069]
The eyepiece 13c adjacent to the pentaprism 13a allows the user to see the subject, while a part of the light beam that has passed through the pentaprism 13a is guided to a photosensor (not shown) in the photometry circuit 121, where it is detected. A well-known photometric process is performed based on the light quantity.
[0070]
Next, details of the imaging unit 15 in the camera 1 of the present embodiment will be described.
[0071]
3, 4, and 5 are views showing a part of the imaging unit 15 in the camera 1 of the present embodiment, and FIG. 3 is an exploded perspective view of a main part showing the imaging unit in an exploded manner. is there.
[0072]
4 is a perspective view showing a state in which the imaging unit is assembled in a cut state, and FIG. 5 is a cross-sectional view taken along the cut surface in FIG.
[0073]
Note that the imaging unit 15 of the camera 1 of the present embodiment is a unit configured by a plurality of members including the shutter unit 14 as described above, but the main part is illustrated in FIGS. 3 to 5. The illustration of the shutter portion 14 is omitted.
[0074]
3 to 5, in order to show the positional relationship between the constituent members, the image pickup device 27 is mounted in the vicinity of the image pickup unit 15, and includes an image signal processing circuit and a work memory. A main circuit board 16 on which an electric circuit of the imaging system is mounted is also illustrated.
[0075]
Note that 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 will be omitted.
[0076]
The image pickup unit 15 is composed of a CCD or the like, and has an image pickup element 27 that obtains an image signal corresponding to the light that is transmitted through the shooting optical system 12a and irradiated on its own photoelectric conversion surface, and a thin plate-like member that fixes and supports the image pickup element 27. An image sensor fixing plate 28 made of a member and an optical element disposed on the photoelectric conversion surface side of the image sensor 27 and formed to remove a high frequency component from a subject luminous flux that is irradiated through the photographing optical system 12a. An optical low-pass filter (hereinafter referred to as an optical LPF) 25 and a low-pass filter receiving member which 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. 26 and the image pickup device 27 are housed and fixedly held, and the optical LPF 25 (optical device) is closely attached to and supported by the peripheral portion or the vicinity thereof. An image sensor housing case member 24 (hereinafter referred to as a CCD case 24) disposed so as to be in close contact with a dustproof filter receiving member 23, which will be described later, at a predetermined portion, and disposed on the front side of the CCD case 24 A dust-proof filter receiving member 23 that supports the dust-proof filter 21 in close contact with the peripheral portion or the vicinity thereof, and a photoelectric conversion surface side of the image sensor 27 that is supported by the dust-proof filter receiving member 23 and on the front side of the optical LPF 25 On the side, a dustproof filter 21 that is a dustproof member disposed opposite to a predetermined position having a predetermined interval between the optical LPF 25, and a predetermined distance with respect to the dustproof filter 21 that is disposed on the periphery of the dustproof filter 21. A vibrating member for applying vibration, for example, a piezoelectric element 22 made of an electromechanical transducer or the like and a dustproof filter 21 are connected to a dustproof filter. Is constituted by the pressing member 20 or the like made of an elastic body for fixing and holding are joined hermetically with respect to filter receiving member 23.
[0077]
The image sensor 27 receives an object light beam transmitted through the photographing optical system 12a on its own photoelectric conversion surface and performs a photoelectric conversion process to obtain an image signal corresponding to the object image formed on the photoelectric conversion surface. For example, a charge-coupled device (CCD) is used.
[0078]
The image sensor 27 is mounted at a predetermined position on the main circuit board 16 via the image sensor fixing plate 28.
[0079]
As described above, the image signal processing circuit, the work memory, and the like are mounted on the main circuit board 16, and signals output from the image sensor 27 are processed by these circuits.
[0080]
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.
[0081]
A CCD case 24 is disposed so as to cover the image sensor 27, the low-pass filter receiving member 26, and the optical LPF 25.
[0082]
In other words, the CCD case 24 is provided with a rectangular opening 24c in a substantially central portion, and the optical LPF 25 and the image sensor 27 are disposed in the opening 24c from the rear side. .
[0083]
A step portion 24a having a substantially L-shaped cross section is formed on the inner peripheral edge portion on the rear side of the opening 24c as shown in FIGS.
[0084]
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.
[0085]
The low-pass filter receiving member 26 is disposed at a position that avoids the effective range of the photoelectric conversion surface in 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.
[0086]
In addition, substantially airtightness is maintained between the optical LPF 25 and the image sensor 27.
[0087]
Thereby, an elastic force in the optical axis direction by the low-pass filter receiving member 26 acts on the optical LPF 25.
[0088]
Therefore, a low-pass filter that displaces the optical LPF 25 in the optical axis direction by disposing 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 position of the optical LPF 25 in the optical axis direction is regulated against the elastic force of the receiving member 26.
[0089]
In other words, the position of the optical LPF 25 inserted from the back side into the opening 24 c of the CCD case 24 is regulated in the optical axis direction by the step portion 24 a of the CCD case 24.
[0090]
Thus, the optical LPF 25 is prevented from coming out from the inside of the CCD case 24 toward the front side.
[0091]
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.
[0092]
In this case, a low-pass filter receiving member 26 is sandwiched between the optical LPF 25 and the image sensor 27 at the periphery.
[0093]
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.
[0094]
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.
[0095]
Further, the main circuit board 16 is fixed to the image sensor fixing plate 28 with screws 16d through spacers 16c.
[0096]
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.
[0097]
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.
[0098]
On the other hand, annular projections 23d (not shown in FIG. 3) corresponding to the circumferential grooves 24d of the CCD case 24 are all provided at predetermined positions on the peripheral side of the dustproof filter receiving member 23 and on the back side. It is formed in a substantially annular shape over the circumference.
[0099]
Therefore, the CCD case 24 and the dustproof filter receiving member 23 are fitted in the annular convex portion 23d and the circumferential groove 24d so that the annular region, that is, the region where the circumferential groove 24d and the annular convex portion 23d are formed. They are adapted to fit in a substantially airtight manner.
[0100]
The dust 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 a predetermined portion on the front side of the optical LPF 25. Are arranged to face each other with an interval of.
[0101]
In addition, a peripheral portion of one surface (back side in the present embodiment) of the dustproof filter 21 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 adhesive bonding.
[0102]
The piezoelectric element 22 is configured such that a predetermined vibration can be generated in the dustproof filter 21 by applying a predetermined driving voltage from the outside.
[0103]
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.
[0104]
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.
[0105]
The opening 23f is set so that the subject light flux that has passed through the photographing optical system 12a passes and the light flux is sufficiently large to irradiate the photoelectric conversion surface of the image sensor 27 disposed behind the subject light flux. ing.
[0106]
A wall portion 23e (see FIGS. 4 and 5) protruding to the front surface side is formed in a substantially annular shape at the peripheral edge 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.
[0107]
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 so as to protrude toward the front surface side. .
[0108]
The protruding portion 23a is a portion formed to fix the pressing member 20 that fixes and holds the dustproof filter 21, and the pressing member 20 is a screw 20a or the like with respect to the distal end portion of the protruding portion 23a. It is fixed by the fastening means.
[0109]
The pressing member 20 is a member formed of an elastic body such as a leaf spring as described above, and has a base end fixed to the protruding portion 23a and a free end abutting against the outer peripheral edge of the dustproof filter 21. By contacting, the dustproof filter 21 is pressed toward the dustproof filter receiving member 23, that is, in the optical axis direction.
[0110]
In this case, the positions of the dustproof filter 21 and the piezoelectric element 22 in the optical axis direction are brought into contact with the receiving portion 23c by a predetermined portion of the piezoelectric element 22 disposed on the outer peripheral edge of the dustproof filter 21 on the back side. Are now regulated.
[0111]
As a result, the dust filter 21 is fixed and held so as to be airtightly bonded to the dust filter receiving member 23 via the piezoelectric element 22.
[0112]
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.
[0113]
Incidentally, as described above, the dustproof filter receiving member 23 and the CCD case 24 are configured such 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 joined airtightly via the piezoelectric element 22 by the urging force of the pressing member 20.
[0114]
Further, the optical LPF 25 disposed in the CCD case 24 is disposed so as to be substantially airtight between the front peripheral side peripheral portion of the optical LPF 25 and the step portion 24 a of the CCD case 24.
[0115]
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. ing.
[0116]
Thus, a predetermined gap 51a is formed in the space between the optical LPF 25 and the dustproof filter 21 facing each other.
[0117]
A space 51 b is formed by the peripheral side of the optical LPF 25, that is, by the CCD case 24, the dustproof filter receiving member 23, and the dustproof filter 21.
[0118]
This space portion 51b is a sealed space formed so as to protrude outside the optical LPF 25 (see FIGS. 4 and 5).
[0119]
The space 51b is set so as to be a wider space than the gap 51a.
[0120]
The space formed by the gap 51a and the space 51b is 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.
[0121]
As described above, in the imaging unit 15 in the camera of the present embodiment, a sealing structure portion that is formed on the optical LPF 25 and the periphery of the dust-proof filter 21 and forms a substantially hermetically sealed space 51 including the gap portion 51a is configured. Yes.
[0122]
And this sealing structure part is provided in the outer position from the periphery of optical LPF25 thru | or its vicinity.
[0123]
Further, in the present embodiment, the dustproof filter receiving member 23 which 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 closely attached to the peripheral portion or the vicinity thereof. The sealing structure portion is constituted by the CCD case 24, which is a second member disposed so as to be in close contact with the dustproof filter receiving member 23 at its own predetermined portion.
[0124]
In the camera of the present embodiment configured as described above, the dust filter 21 is disposed opposite to a predetermined position on the front surface side of the image sensor 27, and formed on the periphery of the photoelectric conversion surface of the image sensor 27 and the dust filter 21. The sealing space 51 to be sealed is configured to prevent dust and the like from adhering to the photoelectric conversion surface of the image sensor 27.
[0125]
In this case, 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 with respect to dust and the like adhering to the exposed surface on the front side of the dustproof filter 21. The dust filter 21 can be removed by applying a predetermined vibration.
[0126]
FIG. 6 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.
[0127]
7 and 8 show changes in the state of the dustproof filter 21 and the piezoelectric element 22 when a driving voltage is applied to the piezoelectric element 22 in FIG. 6, and FIG. 7 is along the line AA in FIG. 8 is a cross-sectional view taken along line BB in FIG.
[0128]
Here, for example, when a negative (minus; one) voltage is applied to the piezoelectric element 22, the dustproof filter 21 is deformed as indicated by the solid line in FIGS. 7 and 8, while the piezoelectric element 22 is positive (plus). ;) When a voltage is applied, the dustproof filter 21 is deformed as indicated by a dotted line in FIG.
[0129]
In this case, since the amplitude is substantially zero at the position of the vibration node as indicated by reference numeral 21a in FIGS. 6 to 8, the receiving portion of the dustproof filter receiving member 23 is located at a portion corresponding to this node 21a. 23c is set to contact.
[0130]
Thereby, the dustproof filter 21 can be efficiently supported without inhibiting the vibration of the dustproof filter 21.
[0131]
In this state, the dustproof filter driving circuit 140 is controlled at a predetermined time and a periodic voltage is applied to the piezoelectric element 22, so that the dustproof filter 21 vibrates and the surface of the dustproof filter 21 is vibrated. Adhered dust and the like are removed.
[0132]
Note that the resonance frequency at this time is determined by the shape, plate thickness, material, and the like of the dust filter 21.
[0133]
In the example shown in FIGS. 6 to 8 described above, the case where the primary vibration is generated is shown. However, the present invention is not limited to this, and higher-order vibration may be generated.
[0134]
FIG. 9 is a diagram conceptually showing the configuration of a vibration means for applying vibration to the dustproof filter 21 in the image pickup unit in the electronic image pickup apparatus.
[0135]
As shown in FIG. 9, the annular piezoelectric element 22 is polarized into 22a and 22b. In this case, the piezoelectric elements 22a and 22b are polarized in the plate thickness direction in a region divided into eight in the circumferential direction, the polarization directions are displayed as plus (+) and minus (−), and the polarization directions are reversed. The areas are arranged alternately. One piezoelectric element 22b is a quarter of the wavelength of vibration relative to the other piezoelectric element 22a (where one wavelength corresponds to the length of the plus (+) and minus (-) polarization regions). They are arranged so as to be shifted by the wavelength (1 / 4λ).
[0136]
A voltage having a predetermined frequency is added to the piezoelectric elements 22 a and 22 b configured in this manner in the respective plate thickness directions by the dustproof filter driving circuit 140.
[0137]
In this case, the frequency signal (first periodic voltage signal) output from the oscillator 34 of the dustproof filter driving circuit 140 is added to the piezoelectric element 22b as it is, while the dustproof filter driving circuit is applied to the piezoelectric element 22a. A signal (second periodic voltage signal) whose phase is shifted by 90 ° is applied by the 140 ° 90 ° phase shifter 35.
[0138]
By applying such a signal to each of the piezoelectric elements 22a and 22b, the dustproof filter 21 rotates in the rotational direction X about the center of the dustproof filter 21 as shown in FIG. 10 (only the dustproof filter 21 is displayed). Bending traveling wave vibrations (vibrations that occur alternately at equal intervals and at equal amplitudes between peaks Y and valleys T) are generated.
[0139]
In addition, when the bending traveling wave uttered by the piezoelectric elements 22a and 22b is viewed at an arbitrary time, it has a substantially symmetrical shape with respect to the central portion (optical axis) of the dust filter 21.
[0140]
FIG. 11 is a circuit diagram schematically showing the configuration of the dustproof filter driving circuit 140 in the electronic imaging apparatus 1 described in FIG. FIG. 12 is a time chart showing the form of each signal output from each component in the dustproof filter drive circuit 140 of FIG.
[0141]
A clock generator 255 is provided inside the body control microcomputer 41. The clock generator 255 is a pulse signal (basic clock) at a frequency sufficiently higher than the signal frequency to be applied to the piezoelectric elements 22a and 22b. Is output (see Sig1 shown in FIG. 12). This basic clock signal is input to the N-ary counter 241 of the dust filter driving circuit 140. The N-ary counter 241 counts the pulse signal and outputs a count end pulse signal every time the predetermined value = N is reached. That is, the basic clock signal is divided by 1 / N (see Sig2 shown in FIG. 12).
[0142]
Since the high and low duty ratio of the divided pulse signal is not 1: 1, the duty ratio is converted to 1: 1 via the first 1/2 frequency dividing circuit 242-1. At this time, the frequency is halved (see Sig3 shown in FIG. 12). The output signal from the first ½ divider circuit 242-1 is output to the second ½ divider circuit 242-2 and the exclusive OR (ExOR) circuit 247. The pulse signal input to the second ½ divider circuit 242-2 is output with the frequency further reduced by half (see Sig4 shown in FIG. 12).
[0143]
Here, in a high state of the pulse signal Sig4, the MOS transistor Q01 (244b1) is turned on. Further, the pulse signal Sig4 is applied to the MOS transistor Q02 (244c1) via the first inverter 243-1. In this case, the MOS transistor Q02 (244c1) is turned on in the low state of the pulse signal Sig4.
[0144]
When the two MOS transistors Q01 (244b1) and Q02 (244c1) connected to the primary side of the transformer A (245-1) are alternately turned on in this way, 2 of the transformer A (245-1) is turned on. On the next side, the Sig5 signal shown in FIG. 12 is generated. In this case, the winding ratio of the transformer A (245-1) is determined by the output voltage of the power supply circuit 153 and the voltage required to drive one piezoelectric element 22a.
[0145]
The resistor R00 (246-1) is provided to limit the excessive current flowing through the transformer A (245-1).
[0146]
When driving the piezoelectric element 22a, it is necessary that Q00 (244a1) is in an ON state and a voltage is applied from the power supply circuit 153 to the center tap of the transformer A (245-1). In this case, the ON / OFF control of Q00 (244a1) is performed from P_PwContA of the body control microcomputer 150.
[0147]
The set value = N of the N-ary counter 241 is set from the port = D_NCnt of the body control microcomputer 150. That is, the body control microcomputer 150 can arbitrarily change the drive frequencies of the piezoelectric elements 22a and 22b by controlling the set value = N.
[0148]
The drive frequency is calculated according to the following equation (1).
[0149]
fdrv = fpls / 4N (1)
Here, N: the set value for the N-ary counter 241
fpls: frequency of output pulse of clock generator 255
fdrv: frequency of a signal applied to the piezoelectric element 22a
In this way, a drive signal (Sig5) having a predetermined voltage is applied to the piezoelectric element 22a.
[0150]
On the other hand, the output signal Sig3 of the first ½ divider circuit 242-1 is output to the third ½ divider circuit 242-2 via the exclusive OR (ExOR) circuit 247. In this case, when the port P_θCont of the body control microcomputer 150 is in a high state, the pulse signal Sig3 is inverted. Thereafter, the signal is output to the third ½ divider circuit 243-2.
[0151]
Further, when the port P_θCont is in a low state, the pulse signal Sig3 is output to the third ½ frequency divider 242-2 as it is (see Sig6 shown in FIG. 12). The pulse signal Sig6 is further reduced to a half frequency by the third ½ divider circuit 242-3 and then output (see Sig7 shown in FIG. 12). As a result, the second inverters 243-2, Q 11 (244 b 2), Q 12 (244 c 2), and the transformer B (245-2) are driven, and a drive signal (Sig 8) having a predetermined voltage is applied to the piezoelectric element 22 b.
[0152]
The functions of the second inverters 243-2, Q11 (244b2), Q12 (244c2), transformer B (245-2), and resistor R10 are the same as those of the first inverters 243-1, Q01 (244b1), Q02 described above. (244c1), transformer A (245-1), and resistor R00 (246-1).
[0153]
In any of the first to third ½ divider circuits 242-1, 242-2, and 242-3, a frequency dividing operation is performed in response to the rising edge of the input pulse signal. ing.
[0154]
Even if the frequency of the pulse signal is the same, when the signal is inverted, the second ½ divider circuit 242-2 and the third ½ divider circuit 242-3 each output A difference in phase occurs in the pulse signal. In this case, the phase difference is 90 °.
[0155]
Therefore, a phase difference of 90 ° is generated between the signal Sig5 applied to the piezoelectric element 22a and the signal Sig8 applied to the piezoelectric element 22b. The phase difference can be controlled by the port P_θCont of the body control microcomputer 150. For example, when the port P_θCont is in a high state, a phase difference of 90 ° is generated. When the port P_θCont is in a low state, no phase difference is generated. That is, by controlling the port P_θCont, different forms of vibration can be applied to the dustproof filter 21.
[0156]
(First embodiment)
FIG. 13 is a flowchart for explaining the operation of the Bucom 150 in the camera system according to the first embodiment of the present invention.
[0157]
The Bucom 150 starts its operation when the camera power SW is turned on. In step S100, processing for starting the camera system is executed. The power supply circuit 153 is controlled to supply power to each circuit unit constituting the camera system. Also, initial setting of each circuit is performed.
[0158]
Step S101 is an operation step for detecting the state of the lens unit 12 by performing a communication operation with the Lucom 205, and is periodically executed. When it is detected in step S102 that the lens unit 12 is attached to the camera body 11, the process proceeds from step S102 to step S103. In step S103, the two piezoelectric elements 22a and 22b provided in the dust filter 21 are driven at the resonance frequency (f0) in the same phase for a predetermined time (T0). A value set in the N-ary counter 241 for exciting the two piezoelectric elements 22 a and 22 b is stored in the nonvolatile memory 129. The non-volatile memory 129 also stores the time (T0) during which the dust filter 21 is vibrated in order to remove dust attached to the dust filter 21. A dustproof operation is performed based on these data. The dust filter 21 vibrates as shown in FIGS. 7 and 8, and dust is removed.
[0159]
On the other hand, if it is not detected in step S102 that the lens unit 12 is attached to the camera body 11, the process proceeds from step S102 to step S104. Step S104 is a processing step for periodically detecting the state of the camera operation SW 152. In step S105, the state of CleanUpSW, which is one of the camera operation SW152, is determined. If the CleanUpSW is operated here, the process proceeds to step S106, and the subroutine “CleanUp operation” is executed. Details of the subroutine “CleanUp operation” will be described later.
[0160]
On the other hand, if the CleanUpSW is not operated in step S105, the process proceeds to step S107. In step S107, the state of the 1st release SW which is one of the camera operation SWs 152 is determined. If the first release SW is ON, the process proceeds to step S108, and if it is OFF, the process proceeds to step S101.
[0161]
In step S108, the luminance information of the subject is obtained from the photometry circuit 121. 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.
[0162]
In the next step S109, detection data of the AF sensor unit 116 is obtained via the AF sensor drive circuit 117. The Bucom 150 calculates the amount of focus shift based on this data. In step S110, it is determined whether or not the calculated amount of deviation is within the permitted range. If not, in step S111, drive control of the taking lens in the taking optical system 12a is performed, and the process returns to step S101.
[0163]
On the other hand, if the amount of deviation is within the permitted range in step S110, the process proceeds to step S112. In step S112, the operation state of the 2nd release SW which is one of the camera operation SWs 152 is determined. When the camera operation SW 152 is operated, the process proceeds to step S113, and when there is no operation, the process proceeds to step S101.
[0164]
In step S113, the aperture of the taking lens in the taking optical system 12a is set based on the Av value calculated in step S105. In step S114, the quick return mirror 13b is driven to the UP position.
[0165]
In the next step S115 to step S117, a dustproof permission flag is set. The dustproof permission flag is a flag for instructing whether or not to execute the dust removal operation in parallel with the imaging operation. When the dustproof permission flag is cleared (“0”), the dust removal operation is prohibited, and when the dustproof permission flag is set (“1”), the dust removal operation is permitted. The dustproof permission flag is set when the shutter speed is longer than the predetermined time. This is because when the shutter speed is long, the time for the dustproof filter 21 to touch the outside air becomes longer, and dust may adhere to the dustproof filter 21 during exposure.
[0166]
Further, when bulb shooting is selected, the shutter 14 is maintained in the open state while the user is turning on the release SW, so there is a risk that dust will adhere. In bulb photography, the open time of the shutter 14 cannot be predicted (the exposure time intended by the user cannot be detected by the camera). Therefore, it is necessary to perform a dust removal operation during bulb photography.
[0167]
Although not particularly mentioned in the present embodiment, it may be determined whether or not to perform the dust removal operation according to the shooting mode. This is because an operation mode (such as a night scene shooting mode) with a large shutter speed exists in the shooting mode.
[0168]
First, in step S115, it is determined whether or not the shutter speed is larger than a predetermined value. If it is equal to or greater than the predetermined value, the process proceeds to step S117 to set the dustproof permission flag. If it is equal to or smaller than the predetermined value, the process proceeds to step S116 to clear the dustproof permission flag.
[0169]
In step S115, it is also determined whether bulb photography is selected. If bulb shooting is selected, step S117 is executed to set the dust-proof permission flag. If bulb shooting is not selected, step S116 is executed to clear the dust-proof permission flag. After execution of step S116 or step S117, the process proceeds to step S118.
[0170]
In step S118, the shutter 14 is subjected to OPEN control. In step S119, a subroutine “imaging operation” is executed. The detailed operation of the subroutine “imaging operation” will be described later. In step S120, the shutter 14 is CLOSE controlled. In step S121, the quick return mirror 13b is driven to the Down position. In step S122, the shutter 14 is charged. In step S123, the aperture of the taking lens in the taking optical system 12a is driven to the open position. In step S124, image data is taken from the image sensor 27, converted into a predetermined format, and stored in a recording medium.
[0171]
FIG. 14 is a diagram for explaining the details of the subroutine “CleanUp operation” (step S106) described in FIG. When the user turns on CleanUpSW, this subroutine is executed. The dust removal operation is automatically executed by the camera as necessary. However, it is convenient if the dust removal operation can be executed by the user's intention separately from the dust removal operation automatically performed by the camera.
[0172]
In addition, in order to perform an operation test in the camera manufacturing process, it is necessary to be able to arbitrarily execute a dust removal operation by manual operation. This subroutine exists to meet these demands. In this routine, the quick return mirror 13b is fixed at the UP position and the shutter 14 is also in the OPEN state, so that the state of the dustproof filter 21 during vibration can be observed. When large dust is attached, it is not preferable to wipe it off between the dustproof filter 21 and the shutter 14. It is also possible to exclude dust from the camera by using the dust removal operation of this routine.
[0173]
First, in step S150, the quick return mirror 13b is moved to the Up state. In step S151, the shutter 14 is set to the OPEN state. In step S152, the two piezoelectric elements 22a and 22b are started to be driven with the frequency f0 and the same phase. Thereby, the dustproof filter 21 starts to vibrate as shown in FIGS.
[0174]
In step S153, the state of the CleanUpSW is detected, and the process waits in step S153 until the CleanUpSW is turned off. While the CleanUpSW is ON, the vibration exciting operation of the dustproof filter 21 is continued. The user only needs to keep the CleanUpSW in the ON state for the required time. When CleanUpSW is turned OFF, the process proceeds to step S154, and driving of the piezoelectric elements 22a and 22b provided in the dustproof filter 21 is stopped. Thereafter, the process proceeds to step S155.
[0175]
In step S155, the shutter 14 is set to the Close state. In step S156, the quick return mirror 13b is driven to the Down position. In step S157, the shutter 14 is charged. Then return.
[0176]
FIG. 15 is a diagram for explaining the details of the subroutine “imaging operation” (step S119) described in FIG. In step S200, the state of the dustproof permission flag is determined. If the dustproof permission flag is “1”, the process proceeds to step S201 to start the vibration operation of the dustproof filter 21, and if the dustproof permission flag is “0”, the process proceeds to step S202. In step S201, a frequency (f0 + Δf) and in-phase drive signal is applied to the two piezoelectric elements 22a and 22b. f0 is a resonance frequency, and Δf is a shift amount described later.
[0177]
The resonance frequency f0 is determined by the material and shape of the dust filter 21. When the dustproof filter 21 is driven at the resonance frequency f0, the amplitude of the dustproof filter 21 becomes maximum as shown in FIG. The greater the amplitude of the dustproof filter 21, the greater the ability to remove dust. However, at the resonance frequency f0, the impedance of the piezoelectric elements 22a and 22b decreases, so that the power required to drive the dust filter 21 increases. Further, if the dustproof filter 21 is greatly deformed, the aberration generated by the dustproof filter 21 may increase, leading to image degradation.
[0178]
Therefore, in the present embodiment, in consideration of these problems, the drive frequency of the dustproof filter 21 during the imaging operation is intentionally shifted from the resonance frequency f0. The shift amount (Δf) is stored in the nonvolatile memory 129. When the dustproof filter 21 is driven at a frequency other than the resonance frequency f0, the amplitude of the dustproof filter 21 decreases. However, if the purpose is not to remove dust that has already adhered, but to prevent dust from adhering, Some decrease in amplitude is not a big problem.
[0179]
In the next step S202, the image processing controller 128 is instructed to start an imaging operation. In step S203, it is determined whether or not bulb photographing is being performed. If bulb photographing is being performed, the process proceeds to step S204. In step S204, the process waits until the release SW is turned off. When the release SW is turned off, the process proceeds to step S206.
[0180]
On the other hand, if bulb shooting is not being performed in step S203, the process proceeds from step S203 to step S205. In step S205, the timer counter is moved to wait for the shutter time determined in step S108. Thereafter, the process proceeds to step S206.
[0181]
In step S206, an imaging operation stop command is sent to the image processing controller 128. In step S207, the state of the image stabilization permission flag is determined. If the vibration proof permission flag is “1”, the vibration proof operation of the dust proof filter 21 is stopped in step S208, and then the process returns to the main routine. If the image stabilization permission flag is “0”, the process immediately returns to the main routine.
[0182]
According to the first embodiment described above, in a camera system having a function of removing dust by vibrating the dust filter, the dust filter 21 is adjusted at the resonance frequency of the dust filter 21 when the photographing lens is replaced or when the CleanUpSW is operated. In addition to the vibration, the dustproof filter 21 is vibrated at a frequency (f0 + Δf) shifted by Δf from the resonance frequency f0 during an imaging operation for long exposure or bulb photography, resulting in inferior image quality. There is provided an electronic image pickup apparatus that eliminates unnecessary power consumption.
[0183]
(Second Embodiment)
FIG. 17 is a flowchart for explaining the operation of the Bucom 150 in the camera system according to the second embodiment of the present invention. The second embodiment is characterized in that the dustproof filter 21 is intermittently driven in the subroutine “imaging operation” (step S119 in FIG. 13) described in the first embodiment. Other steps are the same as in the first embodiment.
[0184]
First, in step S400, the state of the dustproof permission flag is detected. If the dustproof permission flag is “1”, the process proceeds to step S401 to start the vibration operation of the dustproof filter 21. In step S401, a predetermined drive signal is applied to the piezoelectric elements 22a and 22b that vibrate the dust filter 21. Thereafter, the process proceeds to step S402.
[0185]
On the other hand, if the dustproof permission flag is “0” in step S400, the process immediately proceeds to step S402. In step S402, the image processing controller 128 is instructed to start an imaging operation. In step S403, it is determined whether or not bulb photographing is being performed. If it is bulb photography, the process proceeds to step S405, and the state of the release SW is detected. If it is detected that the release SW is OFF, the process proceeds to step S406. If the release SW is ON, the process proceeds to step S4050. In step S4050, the vibration excitation operation of the dustproof filter 21 is stopped for a predetermined time. Then, the vibration operation is resumed. In step S4051, the apparatus waits for a predetermined time in order to continue the vibration operation. The dust removal operation during bulb photographing is intermittently executed by the actions of steps S4050 and S4051. The bulb photographing operation is used when photographing a subject with low brightness such as a celestial body. Therefore, the exposure time may be very long. Therefore, we want to reduce the power required for the dust removal operation as much as possible. Therefore, the driving power is suppressed by intermittently driving the dust filter 21.
[0186]
On the other hand, if bulb shooting is not being performed in step S403, the process proceeds to step S404. In step S404, the timer counter is moved to wait for the shutter time determined in step S108. Then, control goes to a step S406.
[0187]
  In step S406, an imaging condition stop command is sent to the image processing controller 128. In step S407DustproofThe state of the permission flag is determined.DustproofIf the permission flag is “1”, the vibration operation of the dustproof filter 21 is stopped in step S408, and then the process returns to the main routine. Also,DustproofIf the permission flag is “0”, the process immediately returns to the main routine.
[0188]
According to the second embodiment described above, in a camera system having a function of removing dust by vibrating the dust filter, the dust filter 21 is moved at the resonance frequency of the dust filter 21 when the photographing lens is replaced or when the CleanUpSW is operated. Since the dustproof filter 21 is vibrated intermittently at the time of the imaging operation for which long exposure is performed or at the time of bulb photography, an electronic imaging device that eliminates wasteful power consumption is provided.
[0189]
(Third embodiment)
FIG. 18 is a flowchart for explaining the operation of the Bucom 150 in the camera system according to the third embodiment of the present invention. The third embodiment is characterized in that, in the subroutine “imaging operation” (step S119 in FIG. 13) described in the first embodiment, the dustproof filter 21 is driven using a bending traveling wave. Other steps are the same as in the first embodiment.
[0190]
First, in step S300, the state of the dustproof permission flag is determined. If the flag is “1”, the process proceeds to step S301 in order to start the vibration excitation operation of the dust filter 21. In step S301, a drive signal having a frequency (fs) and a phase of 90 ° is applied to the two piezoelectric elements 22a and 22b. By this operation, a bending traveling wave as shown in FIG. By selecting a driving method with a small deformation amount of the dustproof filter 21, an increase in aberrations generated by the dustproof filter 21 can be suppressed. After step S301, the process proceeds to step S302.
[0191]
On the other hand, if the flag is “0” in step S300, the process immediately proceeds to step S302. In step S302, the image processing controller 128 is instructed to start an imaging operation. In step S303, it is determined whether or not bulb photographing is being performed. If bulb photographing is being performed, the process proceeds to step S304. In step S304, the process waits until the release SW is turned off. When the release SW is turned off, the process proceeds to step S306.
[0192]
On the other hand, if bulb shooting is not being performed in step S303, the process proceeds from step S303 to step S305, and the timer counter is moved to wait for the shutter time determined in step S108. After step S305, the process proceeds to step S306.
[0193]
In step S306, an instruction to stop the imaging operation is sent to the image processing controller 128. In step S307, the state of the image stabilization permission flag is determined. If the flag is “1”, the vibration proof operation of the dustproof filter 21 is stopped in step S308, and then the process returns to the main routine. If the flag is “0”, the process immediately returns to the main routine.
[0194]
According to the third embodiment described above, in a camera system having a function of removing dust by vibrating the dustproof filter, the resonance frequency (non-bending traveling wave) of the dustproof filter 21 when the photographic lens is replaced or when the CleanUpSW is operated. Thus, the dustproof filter 21 is vibrated, and the dustproof filter 21 is driven so that a bending traveling wave is generated during an imaging operation for long exposure or bulb photography. An electronic imaging device is provided.
[0195]
(Appendix)
1. A photographic optical system that forms an optical image of the subject;
Imaging means including a photoelectric conversion element that converts an optical image formed by the imaging optical system into an electrical signal;
An optical element that is disposed between the photographing optical system and the photoelectric conversion unit and prevents adhesion of dust and the like to the photoelectric conversion surface of the photoelectric conversion unit;
When the shutter time is greater than or equal to a predetermined value or bulb photography is selected, the optical element is vibrated in a predetermined vibration form in association with the imaging operation by the imaging means, thereby performing a dust removal operation on the optical element. Control means to perform,
An electronic imaging apparatus comprising:
[0196]
2. The control means vibrates the optical element at a frequency shifted from a resonance frequency of the optical element. The electronic imaging device described in 1.
[0197]
3. The control means causes the optical element to vibrate intermittently. The electronic imaging device described in 1.
[0198]
4). The control means vibrates the optical element in a form in which a bending traveling wave is generated in the optical element. The electronic imaging device described in 1.
[0199]
【The invention's effect】
According to the present invention, for example, an appropriate dust removal operation is performed at the time of an image capturing operation that performs long exposure, and thus an electronic image capturing device that does not cause deterioration in image quality and eliminates unnecessary power consumption is provided. Is done.
[Brief description of the drawings]
FIG. 1 is a partially cutaway perspective view showing a schematic configuration of an embodiment when the present invention is applied to a digital camera.
FIG. 2 is a block diagram showing a system configuration of a camera according to an embodiment of the present invention.
FIG. 3 is a view showing a part of the image pickup unit 15 in the camera 1 of the present embodiment, and is an exploded perspective view showing a main part in an exploded manner.
FIG. 4 is a view showing a part of the imaging unit 15 in the camera 1 of the present embodiment, and is a perspective view showing a part of the assembled state of the imaging unit.
5 is a view showing a part of the image pickup unit 15 in the camera 1 of the present embodiment, taken along the cut surface of FIG.
6 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. FIG.
7 is a cross-sectional view taken along line AA in FIG. 6, showing changes in the state of the dustproof filter 21 and the piezoelectric element 22 when a driving voltage is applied to the piezoelectric element 22 in FIG.
8 is a cross-sectional view taken along line BB in FIG. 6, showing changes in the state of the dustproof filter 21 and the piezoelectric element 22 when a driving voltage is applied to the piezoelectric element 22 in FIG.
FIG. 9 is a diagram conceptually showing the configuration of a vibration means for applying vibration to the dustproof filter 21 in the image pickup unit of the electronic image pickup apparatus.
FIG. 10 is a diagram showing a bending traveling wave vibration that travels in the rotation direction X about the center of the dust filter 21 as an axis.
11 is a circuit diagram schematically showing a configuration of a dustproof filter driving circuit 140 in the electronic imaging apparatus 1 described in FIG. 2;
12 is a time chart showing the form of each signal output from each component in the dustproof filter drive circuit 140 of FIG. 11. FIG.
FIG. 13 is a flowchart for explaining the operation of the Bucom 150 in the camera system according to the first embodiment of the present invention.
FIG. 14 is a diagram for explaining details of a subroutine “CleanUp operation” (step S106) described in FIG. 13;
FIG. 15 is a diagram for explaining details of a subroutine “imaging operation” described in FIG. 13;
FIG. 16 is a diagram showing the relationship between the amplitude and driving frequency of dustproof glass.
FIG. 17 is a flowchart for explaining the operation of the Bucom 150 in the camera system according to the second embodiment of the present invention.
FIG. 18 is a flowchart for explaining the operation of the Bucom 150 in the camera system according to the third embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Camera, 11 ... Camera body, 11a ... Shooting optical system mounting part, 12 ... Lens unit, 12a ... Shooting optical system, 13 ... Finder apparatus, 13a ... Pentaprism, 13b ... Reflector, 13c ... Eyepiece, 14 ... Shutter unit, 15 ... imaging unit, 16 ... main circuit board, 17 ... release button, 21 ... dust filter, 27 ... imaging device, 28 ... image processing controller, 140 ... dust filter driving circuit, 150 ... microcomputer for body control ( Bucom), 205... Lens control microcomputer (Lucom).

Claims (5)

A taking lens,
An image sensor for converting an image of the photographing lens into an electrical signal;
An optical element for preventing dust and the like from adhering to the photoelectric conversion surface of the imaging element;
Control means for vibrating the optical element to perform dust removal operation;
An operation switch for instructing the dust removal operation;
And the control means includes
When performing the dust removal operation according to the operation of the operation switch, the optical element is vibrated at the resonance frequency of the optical element,
When the long exposure exposure operation is set and the dust removal operation is performed during the exposure period, the optical element is vibrated at a frequency shifted from the resonance frequency of the optical element. Imaging device. Interchangeable shooting lens,
An image sensor for converting an image of the photographing lens into an electrical signal;
An optical element for preventing dust and the like from adhering to the photoelectric conversion surface of the imaging element;
Control means for vibrating the optical element to perform dust removal operation;
Have
The control means includes
When performing dust removal operation when replacing the photographic lens, the optical element is vibrated at the resonance frequency of the optical element,
When performing the dust removal operation during the exposure period is set to the photographing operation of the long-time exposure, it characterized <br/> to vibrate the optical element at a frequency deviated from the resonant frequency of the optical element electronic imaging device. A taking lens,
An image sensor for converting an image of the photographing lens into an electrical signal;
An optical element for preventing dust and the like from adhering to the photoelectric conversion surface of the imaging element;
Control means for vibrating the optical element to perform dust removal operation;
An operation switch for instructing the dust removal operation;
And the control means includes
When performing the dust removal operation according to the operation of the operation switch, the optical element is continuously vibrated,
When performing the dust removal operation for long during shooting operation is set exposure period of exposure, intermittently oscillating the optical element, to that electronic imaging device wherein a. Interchangeable shooting lens,
An image sensor for converting an image of the photographing lens into an electrical signal;
An optical element for preventing dust and the like from adhering to the photoelectric conversion surface of the imaging element;
Control means for vibrating the optical element to perform dust removal operation;
And the control means includes
When performing dust removal operation when replacing the photographic lens, the optical element is continuously vibrated,
When performing the dust removal operation for long during shooting operation is set exposure period of exposure, intermittently oscillating the optical element, to that electronic imaging device wherein a. The control means, when the valve photographing operation is set as the photographing operation of the long-time exposure, according to any one of claims 1 to 4, characterized in that the dust removal operation during the exposure period Electronic imaging device.

Images