JP2008098838A - Digital camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a digital camera with a dust reduction function of removing dust more securely. <P>SOLUTION: The digital camera includes an imaging element 211 which receives subject luminous flux passed through a photographic lens and outputs a subject image signal, a shift mechanism 217 which moves the imaging element 211 in a plane orthogonal to an optical axis of imaging, a dust-proof filter 207 disposed in front of the imaging plane of the imaging element 211, and a piezoelectric element 208 which vibrates the dust-proof filter 207 so as to remove dust sticking on the dust-proof filter 207. When making a first slider 353 and a second slider 355 holding the imaging element 211 by the shift mechanism 217 abut against a movement end, the piezoelectric element 208 generates a vibration wave for the dust-proof filter 207 immediately before the abutment drive of the sliders. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a digital camera having a through image display function, a dust reduction function, and an image stabilization function.

In some digital cameras, if dust adheres to the imaging surface of the image sensor, the shadow will appear and the image quality will deteriorate, so a dust filter is placed on the front of the image sensor and this dust filter is vibrated ultrasonically. Some have a so-called dust reduction function for removing dust adhering thereto (see Patent Document 1). In the dust reduction device disclosed in Patent Document 1, a piezoelectric element is fixed to the peripheral portion of the dust filter, and the piezoelectric element is vibrated by applying an alternating voltage, thereby generating a vibration wave in the dust filter. It has become.
JP 2003-319222 A

In addition, in order to prevent the image from being deteriorated due to the camera shake of the photographer, the so-called image sensor shift that prevents the image deterioration by moving the image sensor in the plane orthogonal to the optical axis according to the camera shake detection signal. A digital camera having a camera shake correction function of the type is known (for example, see Patent Document 2). There is also known a technique for removing dust adhering to an imaging surface by vibrating the imaging device using this imaging device shift mechanism (see Patent Document 3).
JP-A-6-46322 JP 2005-159711 A

The image sensor shift method dust removal can be used as a camera shake correction mechanism, so it is convenient, but it is sufficient if the dust adhering to the optical element provided on the front side of the image sensor is strong. It is difficult to remove dust.

The present invention has been made in view of such circumstances, and an object thereof is to provide a digital camera equipped with a dust reduction function capable of removing dust more reliably.

In order to achieve the above object, a digital camera according to a first aspect of the present invention includes an imaging means for receiving a subject luminous flux that has passed through a photographing lens and outputting a subject image signal, and the imaging means within a plane orthogonal to the imaging optical axis. An image sensor moving mechanism to be moved, a dust filter arranged on the front side of the imaging surface of the imaging means, and a vibration means for vibrating the dust filter to remove dust attached to the dust filter, When the holding unit of the imaging unit is applied to the moving end by the imaging element moving mechanism, the dust filter is vibrated by the vibration unit before and after the application driving.

The digital camera according to a second aspect of the present invention further comprises posture detection means for detecting the posture of the digital camera in the first aspect, and the image sensor moving mechanism based on the detection result of the posture detection means. Change the direction of movement.
Furthermore, in the digital camera according to the third aspect of the present invention, in the first aspect of the invention, when applying to the moving end, the energy supply to the image sensor moving mechanism is stopped immediately before the application and applied by inertia.
Furthermore, the digital camera according to a fourth aspect of the present invention is that in the third aspect of the present invention, after the energy supply is stopped, the vibration filter starts to vibrate the protective filter.
Furthermore, a digital camera according to a fifth aspect of the present invention includes a detection unit that detects immediately before the application in the application of the holding unit to the moving end in the first invention.
Furthermore, the digital camera according to a sixth invention is the digital camera according to the fifth invention, wherein the detection means detects a movement amount of a mechanical switch that is turned on immediately before the application or the holding means, and moves the movement amount. Based on the above, the position immediately before the application position is detected.
Furthermore, a digital camera according to a seventh aspect of the present invention includes a shake detection unit that detects a shake state and outputs a shake signal according to the first aspect of the invention, and is configured to cancel the shake based on the shake signal. The image sensor moving mechanism is driven.
Furthermore, a digital camera according to an eighth aspect of the present invention includes a display unit that displays a moving image of a subject based on the output of the imaging unit in the first aspect.

In order to achieve the above object, a digital camera according to a ninth aspect of the invention is an image pickup means for receiving a subject light flux that has passed through a photographing lens and outputting a subject image signal; an image pickup element moving mechanism for moving the image pickup means; An optical element disposed on the front side of the image pickup surface of the image pickup means, a vibration means for vibrating the optical element, and a holder for holding the image pickup means are removed by the image pickup element moving mechanism when removing the dust. Control means is provided that drives in at least one direction and vibrates the optical element by the vibration means in the vicinity of the end of the moving range.

According to a tenth aspect of the present invention, in the ninth aspect of the invention, the digital camera includes a mechanical switch that detects the vicinity of the end of the moving range, or a detecting unit that detects the amount of movement of the holding portion. The control means vibrates the excitation means based on the output of the detection means.
According to an eleventh aspect of the present invention, the digital camera according to the ninth aspect of the present invention further comprises hand shake detection means for detecting a hand shake state and outputting a hand shake signal. Based on the output of the hand shake detection means, The image sensor moving mechanism is controlled to correct camera shake so as to cancel out the image.
Further, in the digital camera according to the twelfth aspect of the invention, when the dust removal operation is performed in the eleventh aspect, the camera shake correction control is stopped.
The digital camera according to a thirteenth aspect of the present invention is the digital camera according to the ninth aspect, wherein the dust removal operation is performed by operating a button for instructing the dust removal operation, at a power-on reset of the camera, or by a camera shooting preparation operation. At the time of shooting, when the camera's shooting operation is completed, when an interchangeable lens is attached, or when the camera is powered off.
Further, a digital camera according to a fourteenth aspect of the present invention is the ninth aspect of the invention, further comprising display means for displaying a moving image of the subject based on the output of the imaging means.

In order to achieve the above object, a digital camera according to a fifteenth aspect of the present invention is an image sensor, moving means for moving the optical element arranged on the front side of the image sensor so as to give acceleration, and a vibration wave in the optical element. And a control means for generating the vibration wave by the vibration means when acceleration is generated by the movement means.
A digital camera according to a sixteenth aspect of the present invention is the digital camera according to the fifteenth aspect, further comprising detection means for detecting a timing at which the acceleration is generated, and the control means is based on a detection result of the detection means. In the digital camera according to the seventeenth aspect of the invention, the detecting means detects a position where the acceleration is generated.
Furthermore, in the digital camera according to the eighteenth aspect according to the fifteenth aspect, the moving means moves in at least one direction within a plane perpendicular to the optical axis of the photographing lens, and can reciprocate within a moving range. When the acceleration is generated at the moving end of the moving range, the vibration wave is generated.
Furthermore, a digital camera according to a nineteenth aspect of the present invention is the camera according to the fifteenth aspect, further comprising camera posture detection means, and the moving means moves in the direction of gravity according to the detection result of the posture detection means.

ADVANTAGE OF THE INVENTION According to this invention, the digital camera carrying the dust reduction function which can remove dust more reliably can be provided.

Hereinafter, a preferred first embodiment using a digital single-lens reflex camera to which the present invention is applied will be described with reference to the drawings. FIG. 1 is a block diagram showing the overall configuration of the digital single-lens reflex camera according to the first embodiment of the present invention, mainly an electric system. This digital camera has a still image recording function for forming a subject image formed by a photographing lens on an image sensor and recording subject image data on a recording medium based on the output of the image sensor. Also, it has a so-called through image display function (also referred to as a live view display function or an electronic viewfinder function) for displaying a moving image on a display device such as a liquid crystal monitor based on the output of the image sensor. Yes. Furthermore, it has an image sensor shift mechanism that moves the image sensor in a plane orthogonal to the optical axis of the photographic lens, detects camera shake applied to the camera body, and drives the image sensor shift mechanism to cancel this camera shake. It also has an anti-vibration function. In addition, it has an application to the end by the image sensor shift mechanism and a dust removal function (dust reduction function) that removes dust attached to the optical element on the front side of the image sensor by using vibration waves.

The digital single-lens reflex camera according to this embodiment includes an interchangeable lens 100 and a camera body 200. In the present embodiment, the interchangeable lens 100 and the camera body 200 are configured separately and are electrically connected by the communication contact 300, but the interchangeable lens 100 and the camera body 200 can also be configured integrally. .

Inside the interchangeable lens 100, lenses 101 and 102 for focus adjustment and focal length adjustment, and a diaphragm 103 for adjusting the aperture amount are arranged. The lenses 101 and 102 are driven by a lens driving mechanism 107, and the diaphragm 103 is connected to be driven by a diaphragm driving mechanism 109. The lens driving mechanism 107 and the aperture driving mechanism 109 are each connected to a lens CPU 111, and the lens CPU 111 is connected to the camera body 200 via a communication contact 300. The lens CPU 111 controls the inside of the interchangeable lens 100. The lens CPU 111 controls the lens driving mechanism 107 to perform focusing and zoom driving, and also controls the aperture driving mechanism 109 to perform aperture value control.

In the camera body 200, a rotation between a position inclined by 45 degrees with respect to the lens optical axis in order to reflect the subject image to the observation optical system and a position jumped up to guide the subject image to the image sensor 211. A movable movable reflecting mirror 201 is provided. Above the movable reflecting mirror 201, a focusing screen 203 for forming a subject image is disposed. Above the focusing screen 203, a pentaprism 204 for reversing the subject image to the left and right is disposed. . An eyepiece lens 205 for observing the subject image is disposed on the emission side (right side in FIG. 1) of the pentaprism 204, and a photometric sensor 206 is disposed on the side of the pentaprism 204 so as not to interfere with the observation of the subject image. . The photometric sensor 206 is composed of a multi-division photometric element that divides a subject image for photometry. The output of the photometric sensor 206 is connected to the photometric processing circuit 212, and the photometric processing circuit 212 outputs a subject luminance signal corresponding to the subject luminance based on the output of the photometric sensor 206.

Near the center of the movable reflecting mirror 201 described above is a half mirror, and on the back surface of the movable reflecting mirror 201 is a sub mirror 202 for reflecting subject light transmitted through the half mirror portion to the lower part of the camera body 200. Is provided. The sub mirror 202 is rotatable with respect to the movable reflection mirror 201. When the movable reflection mirror 201 is flipped up, the sub mirror 202 is rotated to a position covering the half mirror portion, and the movable reflection mirror 201 is at the subject image observation position. Sometimes it is in an open position with respect to the movable reflecting mirror 201 as shown. The movable reflecting mirror 201 is driven by a movable mirror driving mechanism 222. A distance measuring sensor 218 is disposed below the sub mirror 202, and an output of the distance measuring sensor 218 is connected to a distance measuring circuit 219. The focus sensor 218 and the distance measuring circuit 219 can measure the amount of focus shift of the subject image formed by the lenses 101 and 102.

A focal plane type shutter 213 for controlling the exposure time is disposed behind the movable reflecting mirror 201, and this shutter 213 is driven and controlled by a shutter drive mechanism 221. An imaging element 211 is disposed behind the shutter 213 and photoelectrically converts a subject image formed by the lenses 101 and 102 into an electrical signal. As the image sensor 211, a two-dimensional image sensor such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS) can be used. Between the above-described shutter 213 and the image sensor 211, a dust filter 207 constituting a dust removing mechanism and a piezoelectric element 208 fixed to the peripheral edge of the dust filter 207 are disposed. The piezoelectric element 208 is driven by a dustproof filter drive circuit 220. Details of the dustproof filter driving circuit 220 will be described later with reference to FIGS.

Between the dust-proof filter 207 and the image sensor 211, an optical low-pass filter 209 for cutting a high-frequency component of a subject image and allowing only a low frequency to pass therethrough, and an infrared cut filter 210 for cutting an infrared light component, Is arranged. The dustproof filter 207, the piezoelectric element 208, the low-pass filter 209, the infrared cut filter 210, and the image sensor 211 constitute an image sensor unit 224. The image sensor unit 224 is designed to prevent dust and the like from entering. The gap is reduced. The image sensor unit 224 can be moved by a shift mechanism 217 in a plane orthogonal to the imaging optical axes of the lenses 101 and 102 constituting the photographing lens.

An output of a camera shake detection sensor 214 that detects camera shake applied to the camera body 200 is connected to a camera shake correction circuit 215. The camera shake correction circuit 215 inputs a control signal from the input / output circuit 239 and outputs a camera shake correction signal to the shift mechanism drive circuit 216. The shift mechanism 217 moves the image sensor unit 224 by the actuator in the shift mechanism drive circuit 216. Accordingly, based on the output of the camera shake sensor 214, the camera shake correction circuit 215 outputs a drive signal to the shift mechanism drive circuit 216 so as to cancel the movement of the camera shake, and the shift mechanism 217 is imaged by an actuator in the shift mechanism drive circuit 216. The element unit 224 is moved.

Further, when performing the dust removal operation, the shift mechanism 217 is applied to an end portion of a moving range of a holding unit (a first slider 353 and a second slider 355 to be described later) that holds the image sensor 211, and at the time of the application Dust is also removed using the acceleration of. The detection PR 225 includes a photo reflector (PR) disposed in the shift mechanism 217, and outputs a detection signal according to the movement of the holding unit. The shift mechanism 217 can move the image sensor unit 224 in a first direction in a plane orthogonal to the imaging optical axis and in a second direction orthogonal to the first direction. Details of the image sensor unit 224, the shift mechanism 217, and the shift mechanism drive circuit 216 will be described later with reference to FIGS.

The image sensor 211 is connected to the image sensor drive circuit 223 and is driven and controlled by a control signal from the input / output circuit 239. The photoelectric analog signal output from the image sensor 221 is amplified by the image sensor drive circuit 223 and subjected to analog-digital conversion (AD conversion). The image sensor driving circuit 223 is connected to an image processing circuit 227 in an ASIC (Application Specific Integrated Circuit) 262, and the image processing circuit 227 performs digital amplification (digital gain adjustment processing) and color of digital image data. Various types of image processing such as correction, gamma (γ) correction, contrast correction, black and white / color mode processing, and through image processing are performed.

The image processing circuit 227 is connected to the data bus 261. In addition to the image processing circuit 227, the data bus 261 includes a sequence controller (hereinafter referred to as "body CPU") 229, a compression / decompression circuit 231, a video signal output circuit 233, an SDRAM control circuit 237, and an input / output circuit 239. The communication circuit 241, the recording medium control circuit 243, the flash memory control circuit 247, and the switch detection circuit 253 are connected.

The body CPU 229 connected to the data bus 261 controls the operation of this digital camera. A compression / decompression circuit 231 connected to the data bus 261 is a circuit for compressing the image data stored in the SDRAM 238 in a still image compression format such as JPEG and decompressing the image data during reproduction. Note that image compression is not limited to JPEG, and other compression methods can be applied. The video signal output circuit 233 connected to the data bus 261 is connected to the rear liquid crystal monitor 26 via the liquid crystal monitor drive circuit 235. The video signal output circuit 233 is a circuit for converting the image data stored in the SDRAM 238 or the recording medium 245 into a video signal to be displayed on the rear liquid crystal monitor 26.

The rear liquid crystal monitor 26 is disposed on the rear surface of the camera body 200. However, the rear liquid crystal monitor 26 is not limited to the rear surface and may be other display devices as long as the photographer can observe. The SDRAM 238 is connected to the data bus 261 via the SDRAM control circuit 237, and the SDRAM 238 temporarily stores the image data processed by the image processing circuit 227 or the image data compressed by the compression / expansion circuit 231. This is a buffer memory. Connected to the above-mentioned photometric processing circuit 212, camera shake correction circuit 215, shift mechanism driving circuit 216, distance measuring circuit 219, dust filter driving circuit 220, shutter driving mechanism 221, movable mirror driving mechanism 222, image sensor driving circuit 223, and detection PR 225. The input / output circuit 239 controls data input / output with each circuit such as the body CPU 229 via the data bus 261. The communication circuit 241 connected to the lens CPU 111 via the communication contact 300 is connected to the data bus 261, and exchanges data with the body CPU 229 and the like and communicates control commands.

A recording medium control circuit 243 connected to the data bus 261 is connected to the recording medium 245 and controls recording of image data and the like on the recording medium 245. The recording medium 245 can be loaded with any rewritable recording medium such as an xD picture card (registered trademark), a compact flash (registered trademark), an SD memory card (registered trademark), or a memory stick (registered trademark). And is detachable from the camera body 200. In addition, a hard disk unit such as a microdrive (registered trademark) or a wireless communication unit may be connectable.

A flash memory control circuit 247 connected to the data bus 261 is connected to a flash memory 249, and the flash memory 249 stores a program for controlling the flow of the camera. The body CPU 229 controls the digital camera according to the program stored in the flash memory 249. Note that the flash memory 249 is an electrically rewritable nonvolatile memory.

A power switch 257 that is turned on / off in conjunction with a power switch lever for controlling the power supply of the camera body 200 and the interchangeable lens 100, a switch that is linked to a shutter release button, and a playback button that designates a playback mode. Switch, switch linked to the cross button for instructing the movement of the cursor on the screen of the rear LCD monitor 26, switch linked to the display switching button for switching the through image display, switch linked to the mode dial for instructing the shooting mode, selection Various switches 255 such as an OK switch, a dust removal switch 256, a posture detection switch 258, and an attachment / detachment detection switch 259 that are linked to an OK button for determining each mode etc. are connected to the data bus 261 via the switch detection circuit 253. Yes.

The release button has a first release switch that is turned on when the photographer is half-pressed and a second release switch that is turned on when the photographer is fully pressed. When the first release switch (hereinafter referred to as 1R) is turned on, the camera performs photographing preparation operations such as focus detection, focusing of the photographing lens, and photometry of the subject brightness, and the second release switch (hereinafter referred to as 2R). When it is turned on, a photographing operation for capturing image data of the subject image is executed based on the output of the image sensor. The dust removal switch 256 is a switch that is linked to a dust removal button that is operated when the photographer instructs a dust removal operation. The posture detection switch 258 is a switch that detects whether the camera body 200 is held at the normal position or the vertical position. The attachment / detachment detection switch 259 is a switch that detects whether or not the interchangeable lens 100 is attached to the camera body 200.

Next, the configuration of the image sensor unit 224 and the shift mechanism 217 will be described with reference to FIG. 2A is a perspective view of the image sensor unit 224 and the shift mechanism 217 as viewed from the shutter 213 side, and FIG. 2B is a cross-sectional view taken along line AA. The first substrate 350 formed of a flat hard electric circuit substrate is fixed to the camera body 200. On the first substrate 350, a main substrate 371 on which a control system circuit such as the aforementioned ASIC 262 is mounted is fixed.

A second substrate 351 made of a flat plate is fixed to the front side of the first substrate 350 in parallel with the first substrate 350. Four pins 365a, 365b, 365c, 365d are implanted in the second substrate 351. These four pins 365a, 365b, 365c, 365d are fitted in the long holes 353a, 353b of the first slider 353, and the first slider 353 is slidable in the vertical direction. That is, the pin 365a and the pin 365b arranged in the vertical direction are fitted in the long hole 353a, and the pin 365c and the pin 365d arranged in the vertical direction are fitted in the long hole 353b, and the first slider 353 is slidable in the vertical direction and does not slide in the horizontal direction.

Four pins 367a, 367b, 367c, and 367d are implanted in the first slider 353. The long holes 355a and 355b of the second slider 355 are fitted to these four pins 367a, 367b, 367c and 367d, and are slidable in the left-right direction. That is, the pin 367a and the pin 367b arranged in the left-right direction are fitted in the long hole 355a, and the pin 367c and the pin 367d arranged in the left-right direction are fitted in the long hole 355b, and the second slider 355 is slidable in the left-right direction and does not slide in the up-down direction.

A DC motor (hereinafter abbreviated as a motor) 357 as a Y-direction shifting actuator is fixed to an L-shaped protrusion 351 a near the left side of the second substrate 351, and a drive shaft 357 a of the motor 357 is connected to a drive gear 359. It is fixed to one piece. The drive gear 359 meshes with a spur gear 353c formed on the left side wall of the first slider 353, and the drive gear 359 and the spur gear 353c constitute a so-called rack and pinion. Therefore, when the motor 357 rotates, the drive gear 359 rotates, and the first slider 353 that meshes therewith slides in the vertical direction. In FIG. 2, only the driving gear 359 is depicted as a gear in the driving force transmission system of the motor 357, but it is of course possible to provide a plurality of gear trains to reduce the rotation of the motor 357. .

On the second substrate 351, PR1 constituting the detection PR 225 is disposed at a position facing the spur gear 353c of the first slider 353. This PR1 projects toward the spur gear 353c, receives the reflected light, and outputs a detection signal corresponding to the state of the gear portion of the spur gear 353c. By pulsing and counting this detection signal, the position of the first slider 353 can be detected. By detecting the position, it is possible to predict the application when the first slider is driven.

A DC motor (hereinafter abbreviated as a motor) 361 as an X-direction shifting actuator is fixed to an L-shaped protrusion 353 d provided on the first slider 353, and a drive shaft 361 a of the motor 361 is integrated with the drive gear 363. It is fixed to. The drive gear 363 meshes with a spur gear 355c formed on the side wall of the lower side of the second slider 355, and the drive gear 359 and the spur gear 355c constitute a so-called rack and pinion. Therefore, when the motor 361 rotates, the drive gear 363 rotates, and the second slider 355 that meshes with the drive gear 363 slides in the left-right direction. As in the case of driving in the vertical direction, in FIG. 2, only the driving gear 363 is depicted as the gear in the driving force transmission system of the motor 361, but a plurality of gears are used to reduce the rotation of the motor 361. Of course, it does not matter if a row is provided.

On the first slider 353, PR2 constituting the detection PR225 is arranged at a position facing the spur gear 355c of the second slider 355. The PR2 projects light toward the spur gear 355c, receives the reflected light, and outputs a detection signal corresponding to the state of the gear portion of the spur gear 355c. By pulsing and counting this detection signal, the position of the second slider 355 can be detected. By detecting the position of the second slider 355, it is possible to predict the application when the second slider is driven.

An imaging substrate 373 is provided inside the substantially central opening of the second slider 355. The imaging element 211 is fixed on the imaging substrate 373, and an infrared cut filter 210 is disposed on the front side thereof, and an optical low-pass filter 209 is disposed on the front side. In addition, the piezoelectric element 208 is fixed to the attachment portion 355d at the periphery of the opening of the second slider 355 along the circumference of the opening. And the dustproof filter 207 is arrange | positioned through the vibration transmission body which is not shown in figure. The dust filter 207 is in pressure contact with the piezoelectric element 208 via a vibration transmitting body by a fastener 369. The subject image formed by the lenses 101 and 102 passes through the dust filter 207, the optical low-pass filter 209, and the infrared cut filter 210 and forms an image on the image sensor 211.

Since the image sensor unit 224 and the shift mechanism 217 are configured in this manner, the first slider 353 can slide in the vertical direction (Y direction) on the second substrate 351 when the motor 357 rotates. Similarly, when the motor 361 rotates, the second slider 355 can slide in the left-right direction (X direction) on the first slider 353. That is, by driving and controlling the motor 357 and the motor 361, the second slide 355 that fixes the image sensor 211 can freely move in the X and Y directions in a plane orthogonal to the photographing optical axis. Therefore, based on the output of the camera shake sensor 214, the camera shake correction circuit 215 outputs a signal to the motor 357 and the motor 361 of the shift mechanism drive circuit 216 so as to cancel the camera shake, and the image sensor 211 is spatially moved to thereby shake the camera shake. Can be countered.

In addition, when the piezoelectric element 208 receives a drive signal from a dustproof filter drive circuit 220 described later, it vibrates at a frequency higher than the audible frequency and generates a vibration wave, whereby dust attached to the dustproof filter 207 can be removed. Further, the first slider 353 or the second slider 355 can be moved at a high speed, and dust attached to the dustproof filter 207 can be removed by acceleration applied to the end portion. Here, when the first slider 353 moves in the Y direction, the contact with the end means that the pins 365a and 365c are applied to the long holes 353a and 353b, or the pins 365b and 365d are applied. In other words, when the second slider 355 moves in the X direction, the pins 367a and 367c are applied to the long holes 355a and 355b, or the pins 367b and 367d are applied.

In the present embodiment, the driving range of the first slider 353 and the second slider 355 is determined by the long holes 353a, 353b, 355a, 355b and the pins 365a, 365b, 365c, 365d, 367a, 367b, 367c, 367d. For example, the second substrate 351 and the first slider 353 are provided with contact portions, and the first slider 353 and the second slider 355 are contacted. A contact portion may be provided and moved between them. In that case, if the abutting portion is provided on a movable member such as the first slider 353, the driving mechanism may be adversely affected. Therefore, the abutting portion is preferably provided on a fixed member. In this case, “contacting the end portion” means that each movable portion contacts the contact portion.

In this embodiment, the DC motor 361 is provided as the X-direction shift actuator and the DC motor 357 is provided as the Y-direction shift actuator. However, the present invention is not limited to this, and a stepping motor or an ultrasonic motor may be employed. good. When the stepping motor is employed, there is an advantage that the position moved from the reference position can be detected by counting the number of applied pulses. When a stepping motor is employed, the detection PR 225 can be eliminated. In addition, the first slider 353 and the second slider 355 are orthogonal to each other. However, the present invention is not limited to this. For example, the first slider 353 and the second slider 355 may be configured to move in an arc shape. Furthermore, although the structure using the rack and pinion is used as the shift mechanism 217 of the image sensor 211, the present invention is not limited to this, and various structures such as a shift mechanism using a piezoelectric element can be used.

Next, the configuration of the camera shake sensor 214, the camera shake correction circuit 215, and the shift mechanism drive circuit 216 in the present embodiment will be described with reference to FIG. The camera shake sensor 214 detects a camera shake in the longitudinal direction (X direction) of the camera body 200 as the first direction, and a camera shake in the height direction (Y direction) of the camera body 200 as the second direction. It comprises a camera shake sensor Y214b to be detected. Here, the camera shake sensor includes a known gyro, angular velocity sensor, acceleration sensor, shock sensor, or the like.

The camera shake correction circuit 215 includes an X signal processing circuit 215a, a Y signal processing circuit 215b, and a camera shake calculation circuit 215c connected to outputs of these circuits. The X signal processing circuit 215a is connected so that the output of the camera shake sensor X214a is input, processes a signal related to camera shake in the X-axis direction, and outputs the signal to the camera shake calculation circuit 215c. The Y signal processing circuit 215b is connected so that the output of the camera shake sensor Y214b is input, processes a signal related to camera shake in the Y-axis direction, and outputs the signal to the camera shake calculation circuit 215c. The camera shake calculation circuit 215c calculates a drive amount necessary to cancel the camera shake in the X-axis direction and the Y-axis direction, respectively, and outputs it to the shift mechanism drive circuit 216.

The shift mechanism drive circuit 216 includes a driver 216a, a motor 361 as an X-direction shift actuator, and a motor 357 as a Y-direction shift actuator. These actuators correspond to the motor 361 and the motor 357 shown in FIG. The X-direction shift actuator 361 and the Y-direction shift actuator 357 are driven according to the output from the driver 216a.

The driver 216 a is connected so that the output of the camera shake calculation circuit 215 c of the camera shake correction circuit 215 is input. Then, the driver 216a drives and controls the X-direction shift actuator 361 and the Y-direction shift actuator 357 according to the output of the camera shake correction circuit 215, so that the camera shake correction operation is performed.

A camera shake correction operation start / stop control signal output from the body CPU 229 via the input / output circuit 239 is applied to the camera shake correction circuit 215, and start and stop of camera shake correction are controlled according to this control signal. When the start control of the camera shake correction operation is performed, the camera shake correction circuit 215 outputs a control signal to the driver 216a of the shift mechanism drive circuit 216.

Next, a dustproof filter drive circuit 220 that performs a dust removal operation and its peripheral circuits will be described with reference to FIGS. The N-ary counter 41 arranged in the dust filter driving circuit 220 inputs a clock pulse (Sig1) output from the clock generator 55 in the input / output circuit 239, and D_NCnt which is an output IO port of the input / output circuit 239. The counter set value N output from the terminal is input. The N-ary counter 41 counts clock pulses and outputs a pulse (Sig2) when the counter set value N is reached. The ½ divider circuit 42 composed of D flip-flops to which this pulse Sig2 is input is a divider circuit whose output (Sig3) is inverted every time a rising signal of the pulse Sig2 is input.

The output terminal of the 1/2 divider circuit 42 is connected to the input terminal of the inverter 43, and the output terminal of the inverter 43 is connected to the gate of the MOS transistor (Q02) 44c. The source of the MOS transistor (Q02) 44c is connected to one end of the primary side of the transformer 45, and the drain is connected to the drain of the MOS transistor (Q00) 44a for power on / off. The gate is connected to the P_PwCont terminal which is the IO port of the input / output circuit 239, and the source of this transistor is grounded. The output terminal of the 1/2 divider circuit 42 is also connected to the gate of the MOS transistor (Q01) 44b, the source of the MOS transistor (Q01) 44b is connected to the other end on the primary side of the transformer 45, and the drain is connected to the MOS transistor. The drain of the transistor (Q02) 44c is connected.

The primary intermediate tap of the transformer 45 is connected to the power supply circuit 53a via a resistor (R00) 46. One end of the secondary side of the transformer 45 is connected to one end of the piezoelectric element 208, and the other end of the piezoelectric element 208 is grounded. The piezoelectric element 208 receives the boosted AC voltage (Sig4) from the transformer 45 and performs ultrasonic vibration.

As described above, the dust filter driving circuit 220 and its peripheral circuits are configured. First, when an H level signal is applied to the gate of the MOS transistor (Q00) 44a from the P_PwCont terminal of the input / output circuit 239, the transistor (Q00) 44a is an n-channel type, and thus becomes conductive. A power supply voltage is applied to the primary side intermediate tap of the transformer 45.

In this state, when a clock pulse (see Sig1 in FIG. 5) is output from the clock generator 55 of the input / output circuit 239 to the N-ary counter 41, the N-ary counter 41 starts counting, and D_NCnt of the input / output circuit 239 is set. When the count value is set to N, the pulse signal Sig2 is output from the output terminal (see Sig2 in FIG. 5). The ½ divider circuit 42 to which the pulse signal Sig2 from the N-ary counter 41 is input is converted into a pulse signal having a duty ratio of 50% (Sig3 in FIG. 5). This pulse signal is applied to the MOS transistor (Q01) 44b. The voltage is applied to the MOS transistor (Q02) 44c through the gate and the inverter 43.

The MOS transistor (Q01) 44b and the MOS transistor (Q02) 44c are alternately turned on, and the power supply voltage is applied from the power supply circuit 53a to the primary side of the transformer 45 via the intermediate tap. The boosted voltage (Sig 4 in FIG. 5) is output from the secondary side and applied to the piezoelectric element 208. Since the frequency of the high voltage applied to the piezoelectric element 208 can be changed by the set value N set from the D_NCnt terminal of the input / output circuit 239, if the set value N is determined so as to be the resonance frequency of the piezoelectric element 208 Dust can be removed efficiently. The resonance frequency is higher than the audible frequency, and consists of, for example, an ultrasonic frequency. The signal supplied from the input / output circuit 239 to the dustproof filter drive circuit 220 is under the control of the body CPU 229.

In this embodiment, the dust removal is performed by generating a vibration wave having a frequency higher than the audible frequency by the piezoelectric element 208 provided on the dust filter 207, but the vibration is an infrared filter other than the dust filter 207. 210 or the optical low-pass filter 209 may be provided, or may be provided on the imaging surface of the imaging element 211. In addition to using vibration, if the dust attached to the imaging element itself or the optical element disposed on the front side of the imaging element can be removed, for example, by using an air pump or the like Of course, it may be appropriately replaced with various methods such as those that blow away and those that collect and remove dust using static electricity.

Next, the operation of the digital single lens reflex camera according to the first embodiment of the present invention will be described with reference to the flowcharts and time charts shown in FIGS. First, when a power-on reset is performed, for example, when a power supply battery is loaded in the camera body 200, initialization is performed (# 1). In the initial setting, the port and memory of each electronic element are initialized, and a reset operation is performed so that the mechanical parts are in the initial positions. Subsequently, the state of the power switch 257 is detected (# 3). As a result of the detection, if the power switch 257 is in the off state, the standby state in which step # 3 is repeatedly executed is entered. If the detection results in a change from the off state to the on state, the process proceeds to step # 5 and the dust removal operation 1 is performed. Since the interchangeable lens 100 is detached when the power is turned off and dust may adhere to the dustproof filter 207 from the mount opening, the dust removal operation is performed when the power is turned on. In this dust removal operation 1, a dust removal operation by an image pickup device shift method in which the image pickup device 211 is spatially moved by the motors 357 and 361 of the shift mechanism drive circuit 216, and a drive signal is applied to the piezoelectric element 208 by the dustproof filter drive circuit 220. Combine dust removal operation that generates vibration waves to remove dust.

When the dust removal operation 1 in step # 5 is completed or it is detected in step # 3 that the power switch 257 is on, next, various switches 255 such as a 1R switch, 2R switch, shooting mode switch, menu switch, etc., dust removal The states of the switch 256 and the detachable switch 259 are detected by the switch detection circuit 253 (# 7). Subsequently, based on the state of the shooting mode switch and menu switch obtained by the switch detection, mode change processing such as a shooting mode and an image quality mode is performed (# 9). Next, it is determined whether or not it is the through image display mode based on the state of the switch interlocked with the display switching button obtained by the switch detection in step # 7 (# 11). When the through image display mode is set as a result of the determination, in order to switch from the subject image observation by the optical finder to the subject image observation by the through image display by the rear liquid crystal monitor 26, step 51 shown in FIG. The details will be described later.

If the result of determination in step # 11 is not live view display mode, it is next determined whether dust removal switch 256 is on or off (# 13). As a result of the determination, if it is ON, that is, if the photographer operates the dust removal button and instructs the dust removal operation, the process proceeds to step # 15, and the dust removal operation 1 is performed as in step # 5. Execute. When the dust removal operation 1 is completed, the state of the 1R switch is determined based on the detection result obtained by the switch detection in step # 7. If the result of determination is that the 1R switch is off, processing returns to step # 3 and the above steps are repeated.

In step # 17, if the 1R switch is on, that is, if the photographer has pressed the release button halfway, distance measurement and lens drive amount are calculated (# 19). The distance measurement and the lens drive amount calculation are based on the outputs from the distance measurement sensor 218 and the distance measurement circuit 219, and detect the focal shift amount of the lenses 101 and 102 constituting the photographing lens by a known TTL phase difference method. Based on the above, a lens driving amount for driving to the in-focus position is obtained by calculation. Subsequently, based on the focus shift amount or the lens drive amount, it is determined whether or not the lens is within the focusing range (# 21). If the result of determination is that the lens is not within the in-focus range, the lens drive amount obtained in step # 19 is transmitted to the lens CPU 111, and the lens drive mechanism 107 is controlled to drive the photographic lens to the in-focus position ( # 23). When the focusing operation is completed, or when the dust removal switch 256 is off in step # 13, the process proceeds to step # 17, and the above steps are repeated.

If the result of determination in step # 21 is that it is within the in-focus range, the state of the 2R switch is detected (# 25). If the 2R switch is off, that is, if the photographer has not fully pressed the release button, the state of the 1R switch is subsequently detected (# 27), and if the 1R switch is on, step # Returning to 25, if the 1R switch is off, the process returns to step # 3 and the above steps are repeated. That is, when the release button is in the half-pressed state, a standby state is detected in which steps # 25 and # 27 are repeatedly detected, and when the photographer's hand leaves the release button, the process returns to step # 3.

In step # 25, when the 2R switch is turned on as a result of detection, the operation proceeds to an imaging operation for recording a still image based on the output of the imaging device 211. When the imaging operation is started, photometry and exposure amount calculation are first performed (# 29). In this step, the subject brightness is measured based on the output of the photometric sensor 206, and the exposure amount is calculated based on the subject brightness obtained here by calculating the shutter speed and / or the aperture value. Subsequently, in order to prevent the subject image from blurring due to camera shake, the camera shake correction mechanism operation is started (# 31). The operation of the camera shake correction mechanism is started by transmitting a camera shake correction operation start signal to the camera shake correction circuit 215 (see FIG. 3) via the input / output circuit 239, whereby the motors 357 and 361 of the shift mechanism drive circuit 216 are operated. Then, the image sensor 211 is driven so as to cancel the camera shake.

Next, the up operation of the movable reflecting mirror 201 is performed (# 33). Before the movable reflecting mirror 201 is raised (that is, in the down state), the subject luminous flux that has passed through the lenses 101 and 102 of the photographing lens is reflected by the movable reflecting mirror 201 and formed on the focusing screen 203, and the subject image is optical. It can be observed with a viewfinder. In this state, the subject luminous flux is not guided to the image sensor 211, but can be guided to the image sensor 211 when the movable reflection mirror 201 is raised. Subsequently, the front curtain of the shutter 213 starts traveling, and the shutter 213 is opened (# 35). As a result, a subject image is formed on the image sensor 211, and exposure is started (# 37).

When the exposure time corresponding to the set shutter speed or the shutter speed obtained by calculation in step # 29 has elapsed according to the shooting mode set in step # 9, the rear curtain of the shutter 213 is run and the shutter is closed ( # 39). Subsequently, the movable reflecting mirror 201 is moved down and the shutter 213 is charged (# 41). Since the exposure operation is completed, the operation of the camera shake correction mechanism is stopped (# 43).

In the present embodiment, in the imaging operation at the time of subject image observation by the finder optical system, the shift mechanism 217, the shift mechanism drive circuit 216, and the camera shake correction circuit are between Step # 31 and Step # 43 before and after acquiring image data. The image sensor 211 is driven by a camera shake correction mechanism including the camera control sensor 215 and the camera shake sensor 214 so as to cancel the influence of the shake applied to the camera body. The camera shake correction mechanism only needs to operate before and after the exposure operation in step # 37. For example, the camera shake correction mechanism may be started before the photometric exposure calculation, or may be stopped after media recording described later.

Next, image data is read from the image sensor 211 (# 45), image processing is performed by the image processing circuit 227 or the like (# 47), and a still image is recorded on the recording medium 245 (# 49). When the recording of the still image is finished, the process returns to step # 3 and the above steps are repeated. Through the above steps, when the photographer fully presses the release button while observing the subject image with the optical viewfinder, the image data obtained by the image sensor 211 is recorded on the recording medium 245.

Returning to step # 11, if the through image display mode has been selected by operating the display switching button, the process proceeds to step # 51 in FIG. 7, and the camera shake correction mechanism operation is started in the same manner as in step # 31. This prevents the moving image displayed on the rear liquid crystal monitor 26 from being blurred and unsightly due to camera shake during live view display. Subsequently, as in step # 29, photometry / exposure amount calculation is performed (# 53). Next, as in step # 33, the movable reflecting mirror 201 is moved up (# 55). When the up operation is finished, the shutter 213 is opened as in step # 35 (# 57). As a result, the movable reflecting mirror 201 is retracted from the photographing optical axis and the shutter 213 is opened, so that a subject image is formed on the image sensor 211.

Thereafter, in order to set the electronic shutter speed and sensitivity conditions for driving the image sensor 211, a through image condition setting 1 subroutine is executed using the photometric / exposure amount calculation result obtained in step # 53 ( # 59). By executing this subroutine, an image with appropriate brightness (brightness) can be displayed on the rear liquid crystal monitor 26. Details of this subroutine will be described later with reference to FIG. When the through image condition setting 1 is completed, the through image display is ready, and the live image display of the subject image is started on the rear liquid crystal monitor 26 (# 61). In the present embodiment, the frame rate of the live view display is 30 fps (flame per sec), and the frame interval is 33 msec. The through image display operation is controlled by the image processing circuit 227 in response to the start instruction.

Subsequently, switch detection is performed as in step # 7 (# 63), and mode change processing is performed as in step # 9 (# 65). Based on the state of the display changeover switch obtained at the time of switch detection, it is determined whether or not it is the through image display mode (# 67). If it is not the through image display mode, the through image display mode is canceled. In order to display the subject image with the optical viewfinder, step # 71 and the subsequent steps are executed.

First, the through image display on the rear liquid crystal monitor 26 is stopped (# 71), and then the shutter 213 is closed (# 73) as in step # 39. As a result, the subject image is not guided onto the image sensor 211. Subsequently, the movable reflection mirror 201 is lowered, and the shutter 213 is charged by the shutter (# 75). Through the series of operations, the live view display is stopped, so that the camera shake prevention mechanism by the camera shake correction mechanism is not necessary, and the operation of the camera shake correction mechanism is stopped (# 77). When the operation of the camera shake correction mechanism is stopped, the process returns to step # 3 and the above-described steps are repeated.

Returning to step # 67, if the result of determination is that the through image display mode has been selected, the state of the power switch 257 is then detected (# 69). If the result of detection is OFF, in order to turn off the power, the process proceeds to step # 71 and the subsequent steps to cancel the through image display, and then returns to step # 3.

In step # 69, if the result of determination is that the power switch 257 is on, the state of the dust removal switch 256 is detected (# 81). If the result of detection is on, the dust removal operation is instructed by the photographer, and dust removal operation 2 is performed (# 83). The dust removal operation 1 performs the dust removal operation in a state where the through image display is not performed. The dust removal operation 2 is a dust removal operation performed when the through image display is performed, and details will be described with reference to FIG. It will be described later.

When the dust removal operation 2 is completed or the dust removal switch 256 is off in step # 81, the state of the 2R switch is detected (# 85). If the result of detection is OFF, through image condition setting 2 is executed (# 87). This through image condition setting 2 is a subroutine for the purpose of appropriately maintaining the brightness of the through image display on the liquid crystal monitor 26. Since the through image condition setting 1 in step # 59 was before the through image display, it was performed based on the output of the photometric sensor 206. However, in the through image condition setting 2, the target lightness and the screen lightness based on the previous imaging result are used. Then, the electronic shutter speed and sensitivity at the next imaging are determined from the difference. Here, the brightness is a value corresponding to a weighted average value of each pixel output of the image sensor 211, for example.

As described above, when it is determined in step # 11 that the display mode is the through image display mode, first, in step # 51, the operation of the camera shake correction mechanism is started to prevent image blur due to camera shake. For this reason, when the live view display on the rear liquid crystal monitor 26 is started in step # 61, it is not unsightly due to image blurring. After the through image display is started in step # 61, as long as the through image display mode is maintained and the power switch 257 is on, steps # 63 to # 69 and # 81 to # 87 are executed, and step # 63 is executed. Continue executing the loop back to. During this time, when the dust removal button is operated and the dust removal switch 256 is turned on, the dust removal operation 2 is executed.

Returning to step # 85, when the 2R switch is turned on during live view display, the process proceeds to an imaging operation for recording a still image based on the output of the imaging element 211. When the imaging operation is started, first, the live view display is stopped (# 91), the shutter 213 is closed (# 93), and the charging operation is performed (# 95). The shutter 213 is in an open state during the live view display, but before the exposure operation starts, the shutter 213 for controlling the exposure time is temporarily closed and charged to initialize the shutter 213, thereby exposing the exposure time. Allows control.

Subsequently, the travel of the shutter front curtain of the shutter 213 is started and the shutter is opened (# 97). As a result, a subject image is formed on the image sensor 211, and exposure is started (# 99). When the exposure time corresponding to the set shutter speed or the shutter speed obtained by the calculation in step # 53 has elapsed in accordance with the shooting mode set in step # 9, the rear curtain of the shutter 213 is run and the shutter is closed. (# 101). Subsequently, a down operation of the movable reflecting mirror 201 and a charging operation of the shutter 213 are performed (# 103). Thereafter, reading of image data (# 105), image processing (# 107), and media recording (# 109) are performed. Since these steps are the same as steps # 45, # 47 and # 49 described above, details are omitted. When the media recording is completed, the process returns to step # 53 and operates in the through image display mode.

Note that when displaying a subject image with the finder optical system without displaying a through image, automatic focus adjustment was performed in steps # 19 to # 23. Automatic focusing is not performed because the subject luminous flux is not guided. However, if a distance measuring function such as so-called contrast AF that extracts high-frequency components from the output of the image sensor 211 is installed, automatic focus adjustment can be performed even in the through display mode.

Next, the subroutine of dust removal operation 1 in steps # 5 and # 15 will be described using the flowchart shown in FIG. 9 and the time chart shown in FIG. The dust removal operation in the present embodiment uses the acceleration generated at the drive end by the shift mechanism 217 to remove dust attached to the dust filter 207 and causes the piezoelectric element 208 to ultrasonically vibrate the dust filter 207 before and after the drive end. Thus, dust is easily removed.

When entering the dust removal operation 1 subroutine, first, the first slider 353 and the second slider 355 are driven to the vicinity of the moving end. For this purpose, the driving of the motor 357 for driving the first slider 353 in the Y direction is started (# 121). Subsequently, the PR1 detection signal is pulsed and count processing is performed (# 123), and the moving state of the first slider 353 is detected. Subsequently, based on the result of the count process, it is determined whether or not there is no output from PR1 for a predetermined time (# 125). As a result of the determination, if there is an output from PR1, the process returns to step # 123, and if it is determined that there is no output from the predetermined time PR1, the first slider 353 has hit the end, so The drive is stopped (# 127). With this series of operations, the first slider 353 stops in contact with the end in the Y direction.

Next, steps # 129 to # 135 are executed in order to stop the second slider 355 in contact with the end portion in the X direction. That is, the driving of the motor 361 that drives the second slider 355 in the X direction is started (# 129). Subsequently, the PR2 detection signal is pulsed and counted (# 131), and the movement state of the second slider 355 is detected. Based on the result of the counting process, it is determined whether or not there is no output from PR2 for a predetermined time (# 133). As a result of the determination, if there is an output from PR2, the process returns to step # 131, and if it is determined that there is no output from the predetermined time PR2, the driving of the motor 361 is stopped (# 135). With this series of operations, the second slider 355 stops in contact with the end portion in the X direction.

Next, the set value N corresponding to the vibration frequency of 30 kHz is set in the D_NCnt terminal (see FIG. 4) of the input / output circuit 239 (# 137). Subsequently, based on the detection result of the posture detection switch 258, it is determined whether the camera body is held at the normal position or the vertical position (# 139). The camera body 200 is held in the normal position when the horizontally long direction is orthogonal to the gravity, and the vertically long position is held when the horizontally long direction is in the same direction as gravity.

As a result of the determination of the camera posture, if the camera body 200 is in the normal position, the drive motor is the motor 357 that drives the first slider 353 in the Y-axis direction (# 141), and PR1 is detected PR225. Select (# 143). On the other hand, if the result of determination is that the camera body 200 is in the vertical position, the drive motor is the motor 361 that drives the second slider 355 in the X-axis direction (# 145), and PR2 is selected as the detection PR225. (# 147). By this selection, the image sensor 211 and the dustproof filter 207 can move in the direction of gravity.

When the selection of the detection PR 225 is finished in step # 143 or # 147, the driving of the motor 357 or motor 361 selected in step # 141 or # 145 is started (# 151, timing t1 in FIG. 13). . Subsequently, the PR detection signal selected in step # 143 or # 147 is pulsed and counted (# 153) to detect the movement state of the first or second slider. Based on the result of the counting process, it is determined whether or not there is no output from PR for a predetermined time (# 155). If there is an output from the PR, the process proceeds to step # 157 to determine whether or not the count value is just before the application. In step # 127 or # 135, the position of the first or second slider is detected by counting the number of pulses on the basis of the position where the motor is stopped, and it is determined whether or not it is just before the application. It can be carried out.

If the result of determination is that it is not just before application, the process returns to step # 151 and the above steps are repeated. As a result of the determination, if it is just before application, “H” level is output from the P_PwCont terminal (see FIG. 4) of the input / output circuit 239 (# 159, timing t2 in FIG. 13). By setting the P_PwCont terminal to the “H” level, the transistor (Q00) 44a is turned on, Sig4 is output from the dust filter driving circuit 220, the piezoelectric element 208 starts to vibrate, and performs a dust removing operation. This dust removal operation is continued for 20 msec (# 161).

When 20 msec elapses (timing t3 in FIG. 13), a set value N that is 1 kHz higher than the previous vibration frequency is set in the D_NCnt terminal (# 163), and continues for 20 msec as in step # 161 ( # 165). When 20 msec elapses, a set value N that is 1 kHz higher than the previous vibration frequency is set (# 167), and the “L” level is output from the P_PwCont terminal of the input / output circuit 239 (# 169, t4 in FIG. 13). timing). By setting the P_PwCont terminal to the “L” level, the transistor (Q00) 44a is turned off, the output of Sig4 from the dust filter driving circuit 220 is stopped, and the piezoelectric element 208 stops vibration. When the vibration of the piezoelectric element 208 stops, the process returns to step # 151 and the above steps are repeated. The set value N set in step # 167 is used in the dust removal operation when the motor is driven with the rotation direction reversed next time.

Returning to step # 155, the time is counted from the timing of the black triangle mark in the PR1 output of FIG. 13, and when the predetermined time T has elapsed, it is determined that PR is not output for the predetermined time. Since this state is a state in which the first or second slider is in contact with the end portion, in order to stop the drive of the Y motor 357 or the X motor 361, the supply of power to the motor is stopped (# 171, Timing at t5 in FIG. 13). Even if the power supply of the motor is stopped, the motor does not stop immediately but travels inertially. In this state, it waits for 20 msec to elapse (# 173), and when 20 msec elapses, the driving direction of the selected Y motor 357 or X motor 361 is reversed and driving is resumed (# 175, at t6 in FIG. 13). timing).

Thereafter, it is determined whether or not the motor has been driven a predetermined number of times. If the predetermined number of times has not been reached, the process returns to step # 151 and the above steps are repeated. On the other hand, if the predetermined number of times has been reached, the Y motor 357 or the X motor 361 drives the first slider 353 and the second slider 355 to the center position (# 179). Driving to the center position is performed based on the number of pulses detected by PR from the end. When driving to the center position is completed, the original routine is returned to.

As described above, in the dust removal operation 1, the first slider 353 and the second slider 355 are moved toward the ends in the Y direction and the X direction by driving the motor 357 and the motor 361 (steps # 121 to # 121). # 135). Thereafter, the posture of the camera body 200 is detected, and the motor 357 or 361 to be used and the detection PR 225 are selected according to the detection result, and the operation is started (# 139 to # 153). Subsequently, based on the output of the detection PR 225, when it is about to be applied to the end, a drive signal is supplied from the dustproof filter drive circuit 220 to the piezoelectric element 208, and a dust removal operation using vibration waves is started (# 157). , # 159). Thereafter, the drive frequency applied to the piezoelectric element 208 is sequentially increased from 30 kHz in increments of 1 kHz (# 159 to # 167). And it repeats between an edge part and it is determined whether the frequency | count of a drive of the 1st slider 353 or the 2nd slider 355 reached predetermined number, and when it reaches predetermined number, dust removal operation | movement is complete | finished ( # 171- # 177).

As described above, in the present embodiment, the dust filter 208 is vibrated immediately before the first slider 353 or the second slider 355 hits the end portion, so that the dust is shaken off by the acceleration applied to the end portion. In addition, the dust is removed by vibration waves. When the dustproof filter 208 is vibrated to generate a vibration wave, the adhering dust is in a floating state. When acceleration is applied to the dust in this floating state, the dust is easily shaken off.

Further, in the present embodiment, the piezoelectric element 208 is vibrated at 30 kHz for the first 20 msec and is vibrated at 31 kHz for the next 20 msec, and the frequency of the vibration frequency is sequentially increased every 1 kHz. As a result, as shown in FIG. 13, the vibration frequency is swept from 30 kHz to a predetermined frequency. This is because the resonance point of the piezoelectric element 208 is slightly different for each product, and also varies depending on the environmental temperature or the like in the same product, so by sweeping the vibration frequency in the frequency region where the resonance point exists, This is to efficiently remove dust by vibrating at the resonance point. In addition, the frequency is switched between 30 kHz and 31 kHz in one hitting operation, but one frequency may be used in one hitting operation.

In this embodiment, vibration is generated at the resonance point by open loop control. However, vibration is converted at the resonance point by feedback control so that the vibration energy is converted into an electric signal and the electric signal can be detected. But of course. In this embodiment, the vibration frequency to be swept is set to a predetermined frequency from 30 kHz, but this may be changed to an optimum value according to each device. Furthermore, the “predetermined number of times” in step # 177 may be a number of times sufficient to remove dust or a number of times sufficient to vibrate at the resonance point. Further, the time measured by the timers in steps # 161, # 165, and # 173 is not limited to 20 msec, and may be changed as appropriate.

In the present embodiment, after the first slider 353 and the second slider 355 are moved to the ends, it is determined which motor and detection PR 225 to select based on the output of the attitude detection switch 258. Not limited to this, it is first determined which motor and detection PR 225 to use based on the output of the attitude detection switch 258, and then the selected motor is driven to move to the end. Also good.

Furthermore, in this embodiment, the supply of the drive signal to the piezoelectric element 208 is stopped in step # 169, and then the motor is stopped in step # 171. A drive signal may be applied to the piezoelectric element 208 to perform ultrasonic vibration. It is also possible to stop the driving of the motor when it is determined that it is about to be applied in step # 157 and apply a driving signal to the piezoelectric element 208 during inertial running.

Next, the subroutine of dust removal operation 2 in step # 83 will be described using the flowchart shown in FIG. When the dust removal switch 256 is turned on and the dust removal operation 2 subroutine is entered, the operation of the camera shake correction mechanism is stopped in the same manner as in step # 43 (# 181). In the present embodiment, when the through image display mode is entered, the camera shake correction operation is started in step # 51. However, when the dust removal operation is executed, the image stabilization operation is stopped. Note that the camera shake correction operation is stopped by sending a camera shake correction operation stop control signal from the input / output circuit 239 to the camera shake correction circuit 215.

Subsequently, a subroutine for dust removal operation 1 is executed (# 183). In the dust removal operation 1 subroutine, as described above, the shift mechanism 217 is driven to drive the first slider 353 and the second slider 355 holding the image sensor 211 and the dustproof filter 208 toward the end, and the piezoelectric element. The dust filter 207 is vibrated by 208 to remove dust.

When the subroutine of dust removal operation 1 is completed, the operation of the camera shake correction mechanism is resumed in the same manner as in step # 31. When the operation of the camera shake correction mechanism is resumed, the camera shake correction mechanism operates so as to cancel the camera shake applied to the camera body 200. Therefore, the through image display of the liquid crystal monitor 26 is not affected by camera shake, and the subject image is easy to see.

As described above, in the dust removal operation 2 of the present embodiment, after the operation of the camera shake correction mechanism is interrupted in step # 181, the dust removal operation is started in step # 183. When the dust removal operation is completed, the operation of the camera shake correction mechanism (anti-vibration operation) is resumed in step # 185. For this reason, the dust removal operation and the image stabilization operation are not performed at the same time, the current consumption increases, and the possibility that the camera operation becomes unstable is reduced. In addition, the possibility of adverse effects on the image stabilization operation due to noise generated during the dust removal operation is reduced.

Next, “through image condition setting 1” and “through image condition setting 2” will be described with reference to FIG. As described above, this subroutine is for adjusting the image brightness when the subject image is displayed on the rear liquid crystal monitor 26. First, when the through image condition setting 1 subroutine is entered, in step # 201, the electronic shutter speed TV1 and sensitivity SV1 at the time of the next imaging are determined based on the output BVs of the photometric sensor 206. Since the aperture value when displaying a through image is an open aperture value, if this aperture value is AVs,
AVs + TV1 = BVs + SV1
There is a relationship
BVs-AVs = TV1-SV1
It becomes.

Since the left side of this equation is a known value, TV1 and SV1 may be obtained from the value on the left side according to a program line or a table as appropriate. Thereafter, the determined electronic shutter speed TV1 and sensitivity SV1 are stored and set in the respective registers (# 207). The image sensor drive circuit 223 performs drive control of the image sensor 211 based on TV1 and SV1 set and stored here, and reads out a photoelectric conversion signal. When the setting of TV1 and SV1 is completed in step # 207, the flow returns to the original flow.

Next, “through image condition setting 2” will be described. When entering the setting 2 subroutine, first, a difference ΔEV between the target image brightness (predetermined value) and the image brightness at the time of previous imaging is calculated (# 203). Subsequently, the electronic shutter speed TV1 and sensitivity SV1 at the time of the next imaging are determined so that the image brightness is constant (# 205). This decision is based on the following factors:
・ Aperture value AV0
-Electronic shutter speed TV0 at the time of previous imaging
・ Sensitivity SV0 at the time of previous imaging
The difference ΔEV between the target image brightness and the previous image brightness
First, as a basic expression of exposure conditions, AV0 + TV0 = BV0 + SV0
It is.

Here, BV0 is the previous luminance, but the true value is not known and is a provisional value in the above basic formula. Since the true luminance value BV0 is different from the target, ie, ΔEV,
BV0 = AV0 + TV0−SV0 + ΔEV
= AV1 + TV1-SV1
Thus, TV1 and SV1 are obtained from this relational expression. Here, the difference ΔEV may be obtained from, for example, the difference between the weighted average of the output of each pixel of the image sensor and the target value. When step # 205 ends, the process proceeds to step # 207 described above, and after executing this step, the process returns to the original flow.

As described above, in the first embodiment of the present invention, when the dust removal operation is performed when the dust removal button is operated or at the time of power-on reset, the image pickup device 211 is moved by the shift mechanism 217. At the same time, dust is removed by acceleration, and vibration waves are generated in a dustproof filter 207 as an optical element provided in front of the image sensor 211 to remove dust. For this reason, it is possible to remove dust more effectively than the dust removal by the so-called image pickup element shift method in which the image pickup element 211 is moved.

Next, a second embodiment of the present invention will be described with reference to FIGS. In the first embodiment, it is determined based on the count value of the detection PR 225 that the first slider 353 or the second slider 355 is about to reach the end, but in the second embodiment, the end The determination is made on the basis of the output of a mechanical switch whose signal changes immediately before reaching.

The configuration of the second embodiment is as shown in FIG. 14 for the overall configuration diagram shown in FIG. 1, FIG. 15 for the external view showing the configuration of the image sensor unit and shift mechanism shown in FIG. 16 and FIG. 17 and the time chart shown in FIG. 13 is the same as in the first embodiment except for the time chart shown in FIG.

In the block diagram showing the overall configuration shown in FIG. 14, in place of the detection PR 225 of the first embodiment, a win detection switch (abbreviated as “detection SW” in the figure) 228 is provided in the second embodiment. It is. The contact detection switch 228 is a mechanical switch that changes from on to off or from off to on just before the first slider 353 or the second slider 355 hits the end. Except for the contact detection switch 228, the second embodiment is the same as the first embodiment shown in FIG.

Next, in the perspective view showing the configuration of the image sensor unit 224 and the shift mechanism 217 shown in FIG. 15, instead of the detection PR 225 in the first embodiment, a contact detection switch 228 is arranged in the second embodiment. ing. Protrusions 353e and 353f are provided on the right side of the first slider 353, and a first contact detection switch 228a is provided on the movement path of the protrusions 353e and 353f. The protrusions 353e and 353f change the state of the first contact detection switch 228a from on to off or from off to on just before the first slider 353 contacts the end. The output signal of the touch detection switch 228 is turned on when applied, and the output level is “L” level. On the other hand, it is off when not applied, and the output signal level outputs the “H” level.

Similarly, protrusions 355e and 355f are provided on the upper side of the second slider 355, and a second contact detection switch 228b is provided on the movement path of the protrusions. The protrusions 355e and 355f change the state of the second contact detection switch 228b from on to off or from off to on just before the second slider 355 contacts the end. Other configurations of the image sensor unit and the shift mechanism are the same as those in the first embodiment, and thus detailed description thereof is omitted.

Since the operation of the second embodiment is the same as that of the first embodiment except for the dust removal operation 1, only the dust removal operation 1 will be described. When the subroutine for dust removal operation 1 is entered, similarly to step # 121, driving of the motor 357 for moving the first slider 353 in the Y direction is started (# 221). Subsequently, the state of the first win detection switch 228a is detected (# 223), and it is determined whether or not the detection signal of the first win detection switch 228a falls (# 225). If the falling edge is not detected, the process returns to step # 223 to repeatedly detect. When the falling of the first hit detection switch 228a is detected, the driving of the motor 357 is stopped (# 227). By these steps, the first slider 353 is moved to the end.

Next, similarly to step # 129, driving of the motor 361 for moving the second slider 355 in the X direction is started (# 229). Subsequently, the state of the second winning detection switch 228b is detected (# 231), and it is determined whether or not the detection signal of the second winning detection switch 228b has fallen (# 233). When the falling is not detected, the process returns to step # 231 to repeatedly detect. When the fall of the second winning detection switch 228b is detected, the driving of the motor 361 is stopped (# 235). By these steps, the second slider 355 is moved to the end.

Next, similarly to step # 137, the set value N corresponding to the vibration frequency of 30 kHz is set in the D_NCnt terminal (see FIG. 4) (# 237). Subsequently, as in the first embodiment, it is determined whether the camera body is held at the normal position or the vertical position based on the detection result of the posture detection switch 258 (# 239). The drive motor is selected according to (# 241, # 245). Since Steps # 239, # 241, and # 245 are the same as Steps # 139, # 141, and # 145 in the first embodiment, detailed description thereof is omitted.

When the motor 357 is selected as the drive motor in step # 241, the first touch detection switch 228a is then selected as the touch detection switch 228 (# 243). In Step # 245, when the motor 361 is selected as the drive motor, the second winning detection switch 228b is next selected as the winning detection switch 228 (# 247).

When the selection of the motor and the contact detection switch is finished, the normal rotation driving of the selected motor is started (# 251, timing t1 in FIG. 18)). When the drive of the motor is started, the first slider 353 or the second slider 355 starts moving, and it is detected whether or not the contact detection switch 228a or 228b outputs a falling signal (# 253). If no falling is detected, the process returns to step # 251 to continue driving the motor.

On the other hand, when the falling signal is detected (timing t2 in FIG. 18), the driving of the motor is stopped (# 255). As a result, the motor stops driving, but the first slider 353 or the second slider 355 continues to move due to inertia until it hits the end. Simultaneously with the stop of driving with MO, the P_PwCont terminal of the input / output circuit 239 outputs the “H” level (# 257). As a result, a drive signal is output from the dustproof filter drive circuit 220 to the piezoelectric element 208, the piezoelectric element 208 vibrates, and a vibration wave is generated in the dustproof filter 207.

In this state, the control waits for 20 msec (# 259), and when 20 msec elapses, a set value N that is 1 kHz higher than the previous set value N is set in the D_NCnt terminal of the input / output circuit 239 (# 261). . As a result, the piezoelectric element 208 vibrates at a high frequency of 1 kHz from immediately before. In this state, 20 msec is waited (# 263), and when 20 msec elapses, a set value N that is 1 kHz higher than the previous set value N is set in the D_NCnt terminal of the input / output circuit 239 (# 265). The set value N set in step # 263 is used for the dust removal operation when the motor is driven with the rotation direction reversed next time.

Next, the “L” level is output from the P_PwCont terminal of the input / output circuit 239 (# 267, timing t3 in FIG. 18). As a result, the dust filter driving circuit 220 stops the oscillation operation, and the piezoelectric element 208 stops the vibration. Subsequently, the motor reverses the rotation direction and starts driving (# 269). That is, when driving in the normal direction, reverse driving is started, while when driving in the reverse direction, normal driving is performed.

When the rotation direction of the motor is reversed and driving is resumed, it is next determined whether or not the motor has been driven a predetermined number of times (# 271). This determination is made based on the number of times the slider is driven to the end, for example, by counting the number of times the motor rotation direction is reversed. The predetermined number of times is not limited as long as dust can be sufficiently removed, and the open loop control is performed so as to vibrate at the resonance frequency of the piezoelectric element 208. The number of times may be sufficient.

If it is determined in step # 271 that the predetermined number of times of driving has not been performed, the process returns to step # 251 and the above steps are repeated. On the other hand, if the drive has been performed a predetermined number of times, the motors 357 and 361 are driven to return to the center position (# 273). The reason for returning to the center position is that it is desirable to be at the center position when performing the camera shake correction operation. As a method of returning to the center position, an average driving time from end to end is used, and after driving to the end once, driving is performed for a time required to stop at the center position based on the average driving time. Various methods can be used. When this centering operation is completed, the original flow is restored.

Also in the second embodiment of the present invention, as in the first embodiment, when the dust removal operation is performed, the image sensor 211 and the dustproof filter 207 are moved by the shift mechanism 217, and the first slider 353 or the second slider 355 is moved. The dust is removed by acceleration at the time of being applied to the end portion, and a vibration wave is generated in a dustproof filter 207 as an optical element provided on the front surface of the image sensor 211 to remove the dust. For this reason, it is possible to remove dust more effectively than the dust removal by the so-called image pickup element shift method alone in which the image pickup element 211 is moved.

In the dust removal operation 1 of the second embodiment, the contact detection switch 228 detects that the first slider 353 or the second slider 355 is just before hitting the end, and the piezoelectric element 208 generates a vibration wave. The generated dust is removed from the dust filter 207. By using a mechanical contact detection switch 228 instead of the photo reflector (PR), the cost can be reduced.

In the first and second embodiments, the dust removal operation is performed only at the time of power-on reset and when the dust removal button is operated. However, the present invention is not limited to this. For example, the release button is pressed halfway to perform the shooting preparation operation. The dust removal operation may be performed at the time of entering, at the time when the photographing operation is completed, at the time of power off, or the like.

In this embodiment, when the live view is displayed, the camera shake correction operation is also started. However, the camera shake correction operation is not started in conjunction with switching to the live view display. The image stabilization operation may be started after an instruction for the image stabilization operation is issued.

Furthermore, in the present embodiment, the image sensor is a digital single-lens reflex camera that includes only the image sensor 211. However, the present invention is not limited to this, and a plurality of image sensors are provided. The present invention can also be applied to a camera that displays an image.

In the description of the embodiments of the present invention, a digital single-lens reflex camera has been described as an example. However, the present invention is not limited to this, and can be applied to any digital camera or electronic imaging apparatus that can move an image sensor.

1 is a block diagram illustrating an overall configuration of a digital single-lens reflex camera according to a first embodiment of the present invention. It is a figure which shows the structure of the image pick-up element unit and shift mechanism in 1st Embodiment of this invention, Comprising: (A) is an external appearance perspective view, (B) is AA sectional drawing. It is a block diagram which shows the circuit structure of the camera-shake sensor, camera-shake correction circuit, and shift mechanism drive circuit in 1st Embodiment of this invention. It is a circuit diagram which shows the circuit structure of the dustproof filter drive circuit in 1st Embodiment of this invention, and its peripheral circuit. FIG. 5 is a time chart showing signal waveforms at various parts in FIG. 4 for explaining operations of the dustproof filter driving circuit and its peripheral circuits in the first embodiment of the present invention. It is a flowchart of the power-on reset in 1st Embodiment of this invention. It is a flowchart of the power-on reset in 1st Embodiment of this invention. It is a flowchart of the power-on reset in 1st Embodiment of this invention. It is a flowchart of the dust removal operation | movement 1 in 1st Embodiment of this invention. It is a flowchart of the dust removal operation | movement 1 in 1st Embodiment of this invention. It is a flowchart of the dust removal operation | movement 2 in 1st Embodiment of this invention. 6 is a flowchart of through image condition setting 1 and through image condition setting 2 in the first embodiment of the present invention. It is a time chart at the time of execution of dust removal operation 1 in a 1st embodiment of the present invention. It is a block diagram which shows the whole structure of the digital single-lens reflex camera which concerns on 2nd Embodiment of this invention. It is a figure which shows the structure of the image pick-up element unit and shift mechanism in 2nd Embodiment of this invention, Comprising: (A) is an external appearance perspective view, (B) is AA sectional drawing. It is a flowchart of the dust removal operation | movement 1 in 2nd Embodiment of this invention. It is a flowchart of the dust removal operation | movement 1 in 2nd Embodiment of this invention. It is a time chart at the time of execution of dust removal operation 1 in a 2nd embodiment of the present invention.

Explanation of symbols

26 Rear LCD Monitor 201 Movable Reflective Mirror 207 Dustproof Filter 208 Piezoelectric Element 209 Optical Low Pass Filter 210 Infrared Cut Filter 211 Image Sensor 212 Photometric Processing Circuit 213 Shutter 214 Camera Shake Sensor 215 Camera Shake Correction Circuit 216 Shift Mechanism Drive Circuit 217 Shift Mechanism 220 Dustproof Filter drive circuit 223 Image sensor drive circuit 224 Image sensor unit 227 Image processing circuit 229 Body CPU
256 Dust removal switch 350 First substrate 351 Second substrate 353 First slider 355 Second slider 357 Y-direction shifting actuator (motor)
361 X-direction shift actuator (motor)

Claims (19)

Imaging means for receiving a subject luminous flux that has passed through the photographing lens and outputting a subject image signal;
An imaging element moving mechanism for moving the imaging means in a plane orthogonal to the imaging optical axis;
A dust-proof filter disposed on the front side of the imaging surface of the imaging means;
Vibration means for vibrating the dust filter to remove dust attached to the dust filter;
Comprising
A digital camera characterized in that the dustproof filter is vibrated by the vibration means before and after the abutting driving when the holding portion of the imaging means is abutted against the moving end by the imaging element moving mechanism.   2. The digital camera according to claim 1, further comprising posture detection means for detecting a posture of the digital camera, and changing a moving direction of the image sensor moving mechanism based on a detection result of the posture detection means. .   2. The digital camera according to claim 1, wherein when applying to the moving end, the energy supply to the image sensor moving mechanism is stopped immediately before the application, and the image is applied by inertia. 3.   4. The digital camera according to claim 3, wherein after the supply of energy is stopped, the vibration of the protective filter is started by the vibration means.   2. The digital camera according to claim 1, further comprising detection means for detecting immediately before the application of the holding unit to the moving end.   The detection means detects a movement amount of a mechanical switch that is turned on immediately before the application, or the holding means, and detects the position immediately before the application position based on the movement amount. The digital camera described in 1.   The digital image pickup apparatus according to claim 1, further comprising a camera shake detection unit that detects a camera shake state and outputs a camera shake signal, and drives the image sensor moving mechanism so as to cancel the camera shake based on the camera shake signal. camera.   2. The digital camera according to claim 1, further comprising display means for displaying a moving image of the subject based on the output of the imaging means. Imaging means for receiving a subject luminous flux that has passed through the photographing lens and outputting a subject image signal;
An image sensor moving mechanism for moving the imaging means;
An optical element disposed on the front side of the imaging surface of the imaging means;
Vibration means for vibrating the optical element;
When removing the dust, the image pickup device moving mechanism drives the holding portion of the image pickup means in at least one direction, and in the vicinity of the end of the moving range, the vibration element is used to move the optical element. Control means to vibrate;
A digital camera comprising:   It has a mechanical switch for detecting that it is in the vicinity of the end of the moving range, or a detecting means for detecting the moving amount of the holding part, and the control means is based on the output of the detecting means. The digital camera according to claim 9, wherein the vibration means is vibrated.   It has a camera shake detection unit that detects a camera shake state and outputs a camera shake signal. Based on the output of the camera shake detection unit, the image sensor moving mechanism is controlled to perform camera shake correction so as to cancel the camera shake state. The digital camera according to claim 9.   12. The digital camera according to claim 11, wherein the dust removal operation is performed after the camera shake correction control is stopped.   The dust removal operation can be performed by operating a button for instructing the dust removal operation, when the camera is powered on, or when the camera is ready for shooting, when the camera is shooting, when an interchangeable lens is attached, or when the camera is attached. The digital camera according to claim 9, which is performed when the power is turned off.   7. The digital camera according to claim 6, further comprising display means for displaying a moving image of the subject based on the output of the imaging means. An image sensor;
Moving means for moving the optical element arranged on the front side of the imaging element so as to give acceleration;
Vibration means for generating a vibration wave in the optical element;
Control means for generating the vibration wave by the vibration means when acceleration is generated by the movement means;
A digital camera comprising:   16. The apparatus according to claim 15, further comprising detection means for detecting a timing at which the acceleration is generated, wherein the control means generates the vibration wave by the vibration means based on a detection result of the detection means. Digital camera.   The digital camera according to claim 16, wherein the detection unit detects a position where the acceleration is generated.   The moving means moves in at least one direction within a plane orthogonal to the optical axis of the photographic lens, and can reciprocate within the moving range, and generates the vibration wave when acceleration occurs at the moving end of the moving range. The digital camera according to claim 15, wherein the digital camera is generated.   16. The digital camera according to claim 15, further comprising camera posture detection means, wherein the moving means moves in the direction of gravity in accordance with a detection result of the posture detection means.