JP2008042406A - Digital camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a digital camera which provides an excellent image even by using a normally open type shutter. <P>SOLUTION: The digital camera includes: a CCD 221 for photographing a luminous flux from a photographing optical system; a movable reflection mirror 201 to be movable between an insertion state to reflect the luminous flux from the photographing optical system and an escaping state escaping from the luminous flux from the photographing optical system; and the shutter 203 which is arranged between the photographing optical system and the CCD 221, and is opened in a charging state. The charging operation of the shutter 203 is prohibited while image data is being read from the CCD 221. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a camera having a live view display function, and more specifically, a so-called live view display function (also referred to as a through image display function or an electronic viewfinder function) that displays an image repeatedly acquired by an image sensor as a moving image on a display device. It has a camera.

In conventional cameras, the subject image is observed with an optical viewfinder. However, recent compact digital cameras abolish the viewfinder optical system together with the optical viewfinder, and continuously acquire images acquired by the image sensor. More and more, so-called live view display functions for displaying on a display device such as a liquid crystal monitor are increasing.

As such a live view display function, for example, the movable mirror is retracted from the photographing optical path and the focal plane shutter is fully opened to guide the subject image to the image sensor, and the obtained subject image is continuously displayed on the liquid crystal monitor. A digital single-lens reflex camera capable of live view that is displayed has been proposed (Patent Document 1). In this case, from the viewpoint of shortening the shutter time lag, it is conceivable to employ a so-called normal open type shutter that is opened in a shutter charge state as disclosed in Patent Document 2.
JP 2002-369042 A JP 2004-61865 A

However, when a normally open type shutter is employed, the subject image signal is read out with the shutter opened, and in that case, there is a possibility of causing a problem that noise is added to the image signal. .

The present invention has been made in view of such circumstances, and an object thereof is to provide a digital camera capable of obtaining a good image even when a normally open type shutter is used.

In order to achieve the above object, a digital camera according to a first aspect of the present invention includes an imaging unit capable of photographing a light beam from a photographing optical system, an insertion state capable of reflecting the light beam from the photographing optical system, A reflection member movable to a retracted state retracted from the light beam, a shutter unit that is disposed between the imaging optical system and the imaging unit, and is opened in a charged state, reads image data from the imaging unit. During this time, the charging operation of the shutter unit is prohibited.
In a digital camera according to a second aspect of the present invention, in the first aspect, the shutter unit is a focal plane shutter.

In order to achieve the above object, a digital camera according to a third aspect of the present invention includes an imaging unit capable of photographing a light beam from a photographing optical system, an insertion state capable of reflecting the light beam from the photographing optical system, and a photographing optical system. A reflecting member movable to a retracted state retracted from the luminous flux, a shutter unit disposed between the imaging optical system and the imaging means and opened in a charged state, the reflecting member and the shutter unit In the first cam section used after exposure, the reflecting member is inserted, and in the second cam section used after exposure, the shutter unit is charged in the first cam section. The transition from the cam section to the second cam section is permitted only after the completion of the reading of the image data of the imaging means.
According to a fourth aspect of the present invention, in the digital camera according to the third aspect, the shutter unit is in an open state in a charged state and in a light-shielded state in an exposure operation complete state.

In order to achieve the above object, a digital camera according to a fifth aspect of the present invention is directed to an imaging device, a reflection mirror that reflects a subject light beam, and a reflection mirror that can move to a retracted position that is out of the subject light beam. A shutter mechanism that is disposed between the image sensor and the shutter curtain is in an open state in a charge-completed state, moves the reflecting mirror to the retracted position prior to the image capturing operation by the image sensor, and After completion of the above, the reflecting mirror is moved to the reflection position, and after the image signal reading operation from the image sensor following the imaging operation is completed, the charging operation of the shutter mechanism is executed.

In order to achieve the above object, a digital camera according to a sixth aspect of the present invention is disposed between an image sensor that receives a subject luminous flux and outputs a subject image signal, a photographing lens, and the image sensor, Includes a shutter mechanism in which the shutter curtain is in an open state, monitor means for displaying a subject image as a moving image based on the subject image signal output from the imaging device, and the imaging operation by the imaging device prior to the imaging operation. Control means for resetting the shutter mechanism and executing the charging operation of the shutter mechanism after completion of the imaging operation and after completion of the reading operation of the image signal from the imaging element.

According to a seventh aspect of the present invention, the digital camera according to the sixth aspect further includes a reflecting mirror that is movable to a position that reflects the subject luminous flux and a retracted position that is out of the subject luminous flux. Prior to the imaging operation, the reflecting mirror is moved to the retracted position, and the reflecting mirror is moved to the reflecting position after the imaging operation is completed and before the shutter mechanism is charged.
According to an eighth aspect of the present invention, in the sixth aspect of the invention, the reflection mirror is a half mirror or a total reflection mirror.

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 light beam from a photographing optical system and outputting a subject image signal, and an insertion state capable of reflecting the light beam from the photographing optical system. A reflecting member movable to a retracted state retracted from a light beam from the photographing optical system, a shutter unit disposed between the photographing optical system and the image pickup means and opened in a charged state, and the above A driving member capable of driving the reflecting member and the shutter unit; and in the first section after the imaging operation by the imaging means, the reflecting member is moved to the reflective insertion state and continues to the first section. In the second section, the shutter unit is charged, and the transition from the first section to the second section is permitted only after the reading of the subject image signal is completed.
According to a tenth aspect of the present invention, in the ninth aspect, the drive member includes a first cam that is interlocked with the reflecting member, and a second cam that is interlocked with the shutter unit. The cam and the second cam have cam surfaces corresponding to the first section and the second section, respectively.

In the digital camera of the present invention, the charging operation of the shutter unit is prohibited during the reading of the image data from the image pickup means. Therefore, a digital image that can obtain a good image even when using a normally open type shutter. A camera 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 a schematic configuration of the internal mechanism of the digital single lens reflex camera according to the first embodiment, (A) is a block diagram of the internal configuration along the optical axis direction of the photographing lens, and (B) is a block diagram. 2 is a block diagram of an internal configuration when viewed from the front side of a camera body 200. FIG.

A release button 21 is disposed on the upper surface of the camera body 200. The release button 21 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 a subject image is executed based on the output of a CCD (Charge Coupled Devices) 221 (see FIG. 6) as an image sensor.

A movable reflecting mirror 201 is disposed in the mirror box of the camera body 200 on the optical axis of the photographing lens 101 (see FIG. 6) disposed inside the lens barrel 100. The movable reflecting mirror 201 captures a subject image and a reflection position inclined by 45 degrees with respect to the optical axis of the photographing lens 101 in order to reflect a subject light beam to a finder optical system (for example, a pentaprism 207). In order to guide to a CCD (Charge Coupled Device) 221), it can be rotated to a retracted position retracted from the photographing optical path. The rotation axis of the movable reflecting mirror 201 is along the direction perpendicular to the paper surface of FIG. The movable reflecting mirror 201 reflects the subject luminous flux upward. In this embodiment, the light is reflected upward. However, the present invention is not limited to this, and the reflection direction of the subject luminous flux is the most appropriate in terms of the arrangement of the mechanism member and the optical member regardless of the right or left side of the camera body. You may choose

A focusing screen 205 is disposed on the reflection optical axis of the movable reflection mirror 201, which is a matte surface for forming an image of a subject light beam by the photographing lens 101. The distance from the movable reflection mirror 201 is equivalent to that of the CCD 221. Arranged in position. Above the focusing screen 205, a pentaprism 207 for horizontally inverting the subject image is disposed. The finder eyepiece 33 is an eyepiece of the finder optical system, and the photographer can look into the eyepiece 33 to check the subject image.

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, a sub mirror 203 is provided for distance measurement for reflecting the subject light beam that has passed through the half mirror section. ing. The sub mirror 203 is rotatable with respect to the movable reflection mirror 201. When the movable reflection mirror 201 is retracted from the photographing optical path and the subject light beam is incident on the CCD 221, the sub mirror 203 is rotated to a position covering the half mirror portion. When the movable reflection mirror 201 is at the subject image observation position (reflection position) as shown in the figure, it rises with respect to the movable reflection mirror 201 and is open so that a part of the subject luminous flux can be reflected by the distance measuring unit. The movable reflecting mirror 201 is driven by a shutter / mirror driving unit 303. Further, a distance measuring unit 218 including a TTL phase difference type distance measuring circuit 217 (see FIG. 6) including a distance measuring sensor is disposed on the reflected light path of the sub-mirror 203. The amount of focus shift of the subject image formed by is detected.

A normally open type focal plane shutter 213 is disposed behind the movable reflecting mirror 201 for exposure time control. The shutter 213 includes a shutter controller 213a including a shutter drive mechanism 215 (FIG. 6) and a shutter mirror. Drive control is performed by the drive unit 303. A CCD 221 serving as an image sensor is disposed behind the shutter 213 and photoelectrically converts a subject image formed by the photographing lens into an electric signal. In the present embodiment, a CCD is used as an image sensor. However, the present invention is not limited to this, and a CMOS (Complementary Metal Oxide) is used.
Needless to say, a two-dimensional imaging device such as Semiconductor) can be used.

A battery 305 for supplying power to the entire camera body is disposed on the left side when viewed from the front of the camera body 200. Further, as will be described later, a mirror shutter (hereinafter abbreviated as “MS”) motor 301 serving as a driving source for the shutter 213 and the movable reflecting mirror 201 is disposed on the right side of the main body, and transmits the driving force of the MS motor 301. The shutter / mirror driving unit 303 for the motor is disposed below the MS motor 301 so as to engage with the driving shaft of the MS motor 301. A shutter control unit 213 a for controlling the driving of the shutter 213 is disposed beside the movable reflecting mirror 201.

Next, the driving mechanism of the movable reflecting mirror 201 and the shutter 213 will be described with reference to FIGS.
2A and 2B are diagrams showing the shutter 213 and the movable reflecting mirror 201, where FIG. 2A is a perspective view of the shutter 213, FIG. 2B is a front view of the shutter 213, and FIG. 2C is a perspective view of the mirror. ) Shows the mirror-down state of the movable reflecting mirror 201, and (E) shows the mirror-up state. As shown in FIG. 2A, a shutter control unit 213a is disposed on the side of the shutter 213, and a shutter set lever 213b protrudes below the shutter control unit 213a. In the initial state, the shutter set lever 213b is in the position (a) indicated by the oblique line in FIG. 2B, and in the shutter charge completed state, the shutter set lever 213b is in the position indicated by the solid line (A) in FIG. Moving.

As described above, the shutter 213 is a normal open type focal plane shutter. In the normal state, the shutter front curtain and the rear curtain are stored in the storage chamber, and the front of the CCD 221 is open. Prior to shooting with the CCD 221, the first and second curtain magnets are held. By returning the shutter set lever 213b to the initial state (a) in this state, the shutter front curtain moves to a closed state that blocks the photographing optical path. When the front curtain magnet is released in this state, exposure starts when the shutter front curtain starts running, and after the exposure time elapses, the shutter rear curtain starts running when the rear curtain magnet is released. End the exposure. After these exposure operations are completed, when the shutter set lever 213b is charged to the position (a) in the charging completion state, the shutter 213 is charged, and the shutter rear curtain is retracted from the photographing optical path and stored in the storage chamber. The front is open. As described above, the normal open type focal plane shutter is a shutter that is open in a normal state and temporarily closed before and after photographing.

When the movable reflecting mirror 201 is in the down state, the sub mirror 203 is rotated to a position opened with respect to the movable reflecting mirror 201 as shown in FIG. As shown in FIG. 2 (D), a mirror down spring 345 is provided on the rotating shaft side of the movable reflecting mirror 201, and this mirror down spring 345 is attached in the counterclockwise direction in FIG. It is energized. The movable reflecting mirror 201 biased by the mirror down spring 345 is regulated at a position of 45 degrees with respect to the photographing optical path by a position regulating pin 349. The mirror drive lever 341 has an L-shape, and is biased by a mirror drive spring 343 in the counterclockwise direction, that is, the up direction for raising the mirror. One end of the mirror driving lever 341 is disposed at a position where it can engage with an engaging pin 347 fixed to the movable reflecting mirror 201. Note that the spring force of the mirror drive spring 343 is always stronger than the spring force of the mirror down spring 345.

In the mirror down state, the mirror drive lever 341 is rotated clockwise by the mirror charge lever 351 against the urging force of the mirror drive spring 343, and is in the position shown in FIG. In this state, when the mirror charge lever 351 that locks the mirror drive lever 341 moves to the right, the mirror drive lever 341 rotates counterclockwise by the biasing force of the mirror drive spring 343. With this rotation, the movable reflecting mirror 201 is rotated from the down position to the up position via the engagement pin 347, and the state shown in FIG. From this state, the mirror charge lever 351 moves to the left against the urging force of the mirror drive spring 343 and reaches the position shown in FIG.

FIG. 3 is an exploded perspective view of the shutter / mirror driving unit 303 to which the driving force of the MS motor 301 is transmitted. The driving force of the MS motor 301 is transmitted to the cam gear 357 via the gear 363. A mirror charge cam 353 having a circumferential surface that changes in the radial direction of the rotation axis of the cam gear 357 is fixed on the upper surface of the cam gear 357, and one end of the mirror charge lever 351 is provided on the cam surface 353a of the mirror charge cam 353. Is engaged. The other end of the mirror charge lever 351 is in contact with the mirror drive lever 341. Since the mirror drive lever 341 is spring-biased in a direction to rotate the mirror charge lever 351 clockwise (see FIG. 2), one end of the mirror charge lever 351 is in pressure contact with the mirror charge cam 353. Become. Accordingly, as the cam gear 357 rotates, the mirror charge cam 353 integrated with the cam gear 357 rotates, and the mirror charge lever 351 pressed against the cam surface of the mirror charge cam 353 rotates.

A cam surface of a shutter charge cam 355 having a circumferential surface that changes in the radial direction of the rotation axis of the cam gear 357 is fixed to the lower surface of the cam gear 357, and one end of the shutter charge lever 361 is attached to the shutter charge cam 355. Is engaged. The other end of the shutter charge lever 361 is in contact with the shutter set lever 213b. Accordingly, as the cam gear 357 rotates, the shutter charge cam 355 integrated therewith also rotates, and the shutter charge lever 361 engaged with the cam surface of the shutter charge cam 355 rotates, and the shutter set lever 213b. Also rotate.

4A shows the cam surface of the mirror charge cam 353 viewed from the AA direction, and FIG. 4B shows the cam surface of the shutter charge cam 355 viewed from the BB direction. The cam surface 353a of the mirror charge cam 353 includes a lift cam a, a top dead center region b, a top dead center region c, a top dead center region d, a reverse lift cam e, a bottom dead center region f, a bottom dead center, as illustrated. It consists of seven areas, the point area g. The cam surface 355a of the shutter charge cam 355 includes a bottom dead center area a, a bottom dead center area b, a lift cam c, a top dead center area d, a top dead center area e, and a top dead center area f as shown in the figure. The bottom dead center region g is composed of seven regions. Note that the relative rotational positional relationship between the mirror charge cam 353 and the shutter charge cam 355 in FIG. 4 has been described with the same reference position, but the arrangement of the mirror charge lever 351 and the shutter char lever 361 indicates the mutual relationship. The reference position changes. Although not shown, a plurality of photo interrupters are provided for detecting the rotation or movement of the mirror charge cam 353, the shutter charge cam 355, or a member driven integrally with these. By these photo interrupters, d detection for outputting L level while in the region d, f detection for outputting L level while in the region f, and g detection for outputting L level while in the region a and region g. (See FIG. 5).

The cam area a is a mirror charge area, and is an area for driving the movable reflection mirror 201 from the retracted position to a reflection position that is positioned in the photographing optical path of the photographing lens 101. In this region, the mirror charge cam 353 changes from the bottom dead center to the top dead center, the movable reflecting mirror 201 is driven from the retracted position in FIG. 2E, and the mirror charge lever 351 is driven from the right to the left in FIG. The drive spring 343 is charged. Further, since the shutter charge cam remains at the bottom dead center, there is no change, the shutter 213 is in an incomplete charge state, and the shutter set lever 213b is in the position shown in FIGS.

The cam area b is a power-off area, the mirror charge cam 353 is at the top dead center, the movable reflecting mirror 201 is in the down state (see FIG. 2D), that is, the finder optical system reflects the subject light beam ( Reflective position). In this state, the subject luminous flux is guided to the finder optical system, so that the subject image can be observed by the optical finder. The shutter charge cam 355 is at the bottom dead center, and the shutter 213 is in an incomplete charge state. This power-off area is not limited to when the camera body is powered off, but is also used when the photographic lens is removed and the mount surface is in an open state.

The cam area c is a shutter charge area, the cam surface 355a of the shutter charge cam 355 changes from the bottom dead center to the top dead center, and the shutter set lever 213b is moved from the position shown in FIGS. B) Driven to the position shown in (a), the shutter charge incomplete state changes to the shutter charge complete state. On the other hand, the cam surface 353a of the mirror charge cam 353 remains at the top dead center, and the movable reflection mirror 201 is located in the photographing optical path and is in a reflection position where the subject light beam is reflected by the finder optical system.

The cam area d is a standby area, the mirror charge cam 353 is at the top dead center, and the movable reflecting mirror 201 is in the down state (see FIG. 2D), that is, an observation position (reflection) that reflects the subject light beam to the finder optical system. Position). In this state, the subject luminous flux is guided to the finder optical system, so that the subject image can be observed by the finder. In addition, since the subject luminous flux is guided to the photometric element 211 and the camera body is in a power-on state, photometry can be performed. Further, since the subject light flux is guided to the distance measuring unit 218 by the sub mirror 203, distance measurement and driving of the photographing lens to the in-focus position (automatic focus adjustment) are possible. Further, in the shutter charge area (cam area c), the shutter charge cam 355 is driven to the top dead center and is maintained in the cam area d, so that the charge completion state is obtained as shown in FIGS. It is in. Note that the shutter 213 is in a charged state, but the shutter set lever 213b is not retracted, so that the shutter curtain cannot run and exposure is not performed. Since the shutter 213 is a normally-on type, the shutter 213 is in an open state. However, since the movable reflecting mirror 201 is in the down position, the subject light beam does not directly enter the CCD 221.

The cam area e is a reverse charge area, and is a transition area from a standby area (cam area d) where observation is performed by a finder optical system to a live view area (cam area f). In this region, the cam surface 353a of the mirror charge cam 353 changes from top dead center to bottom dead center, and the mirror charge lever 351 moves from the position shown in FIG. 2D to the position shown in FIG. The movable reflecting mirror 201 is changed from the reflecting position (down position) to the retracted position (up position) by the urging force of the mirror down spring 345. On the other hand, the cam surface 355a of the shutter charge cam 355 remains at the top dead center and remains unchanged, and the shutter charge completion state is maintained. In addition, since the cam surface 353a of the mirror charge 353 is slightly inclined, it is possible to return from the live view area to the standby area. For this reason, when performing the phase difference AF via the sub mirror 203 during live view or when the photometry by the photometry element 211 is necessary, the MS motor 301 is reversely rotated to return to the standby area, The configuration is such that these operations can be performed. Thus, by reciprocating between the area d and the area f, it is possible to drive the lens for repeated distance measurement and focusing.

The cam area f is a live view area and is an area for performing live view. The mirror charge cam 353 is at the bottom dead center, and the movable reflecting mirror 201 is in the up state (see FIG. 2E), that is, in the retracted position retracted from the photographing optical path. Further, the shutter charge cam 355 is at the top dead center, and the shutter set lever 213b remains in the charged state shown in FIGS. In this state, the movable reflection mirror 201 is in the retracted position (up state), and the normally open type shutter 213 is in the open state, so that a subject image is formed on the CCD 221 serving as the image sensor. Accordingly, although the subject image cannot be observed with the optical finder, the image information from the CCD 221 can be output, and the subject image can be displayed on the liquid crystal monitor 26 based on the image information.

The cam area g is an imaging area, the mirror charge cam 353 is at the bottom dead center, and the movable reflecting mirror 201 is in the up state (see FIG. 2E), that is, at the retracted position retracted from the imaging optical path. Further, since the shutter charge cam 355 moves to the bottom dead center, the shutter set lever 213b moves to the position shown in FIGS. 2B and 2A, so that the shutter front curtain and the rear curtain can move to the retracted position. Yes. This state is when 2R is turned on by operating the release button 21, and the shutter front curtain and the rear curtain each run according to the release of the suction of the shutter magnet that holds the shutter 213, and during this time, the CCD 221 causes the still image to move. Can be imaged and recorded.

The mirror charge cam 353 and the shutter charge cam 355 rotate counterclockwise in the drawing (counterclockwise), and rotate the mirror charge lever 351 and the shutter charge lever 361 having the cam follower configuration as described above. In the normal mode, the shutter charging is completed and the movable reflecting mirror 201 is in the reflecting position (cam area d) and can be observed with the optical viewfinder, and is driven to the cam area g according to the operation of the release button 21 to take a picture. Do. On the other hand, in the live view mode, the shutter charge is completed and the movable reflecting mirror 201 is in the retracted position (cam area f), live view display is performed on the liquid crystal monitor 26, and the cam area g is displayed according to the operation of the release button 21. Driven to shoot.

Next, with reference to FIG. 6, an overall configuration mainly including an electric system of the digital single-lens reflex camera will be described. In the digital single-lens reflex camera according to the present embodiment, as described above, the interchangeable lens 100 and the camera body 200 are configured separately, and both are electrically connected by the communication contact 300. Note that the interchangeable lens 100 and the camera body 200 can 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 lens 101 and the lens 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 main body 200, the movable reflecting mirror 201, the sub mirror 203, the focusing screen 205, and the pentaprism 207 are arranged as described above. The movable reflecting mirror 201 is driven by a mirror driving mechanism 219. An eyepiece lens 209 for observing a subject image is disposed on the emission side of the pentaprism 207, and a photometric sensor 211 is disposed at a position on the side of the pentaprism 207 that does not interfere with the observation of the subject image. The focusing screen 205, the pentaprism 207, and the eyepiece lens 209 constitute a part of the finder optical system.

As described above, the sub mirror 203 is provided on the back surface of the movable mirror 201, and the distance measuring circuit 217 including the distance measuring sensor is disposed in the reflection direction of the sub mirror 203. Further, a shutter 213 is disposed behind the movable mirror 201, and this shutter 213 is driven and controlled by a shutter drive mechanism 215. Further, a CCD 221 as an image sensor is disposed behind the shutter 213, and the subject image formed by the lenses 101 and 102 is photoelectrically converted into an electric signal. The CCD 221 is connected to a CCD drive circuit 223, and analog / digital conversion (AD conversion) is performed by the CCD drive circuit 223. The CCD drive circuit 223 is connected to the image processing circuit 227 via the CCD interface 225. The image processing circuit 227 performs various types of image processing such as color correction, gamma (γ) correction, and contrast correction. Also, image data for live view display on the liquid crystal monitor 26 is generated.

The image processing circuit 227 is an ASIC (Application Specific Integrated).
Circuit-specific integrated circuit) 271 is connected to the data bus 261. In addition to the image processing circuit 227, the data bus 261 includes a body CPU 229, a compression circuit 231, a flash memory control circuit 233, an SDRAM control circuit 236, an input / output circuit 239, a communication circuit 241, a recording medium control circuit 243, and a video signal output. A circuit 247 and a switch detection circuit 253 are connected.

The body CPU 229 connected to the data bus 261 controls the flow of this digital single lens reflex camera. A compression circuit 231 connected to the data bus 261 is a circuit for compressing the image data stored in the SDRAM 237 with JPEG or TIFF. Note that image compression is not limited to JPEG or TIFF, and other compression methods can be applied. A flash memory control circuit 233 connected to the data bus 261 is connected to a flash memory 235. The flash memory 235 stores a program for controlling the flow of the single-lens reflex camera. The CPU 229 controls the digital single-lens reflex camera according to the program stored in the flash memory 235. Note that the flash memory 235 is an electrically rewritable nonvolatile memory. The SDRAM 237 is connected to the data bus 261 via the SDRAM control circuit 236, and the SDRAM 237 temporarily stores the image data processed by the image processing circuit 227 or the image data compressed by the compression circuit 231. This is a buffer memory.

The input / output circuit 239 connected to the above-described photometric sensor 211, shutter drive mechanism 215, distance measuring circuit 217, and mirror drive mechanism 219 controls input / output of data 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, the hard disk may be configured to be connectable via a communication contact.

The video signal output circuit 247 connected to the data bus 261 is connected to the liquid crystal monitor 26 via the liquid crystal monitor drive circuit 249. The video signal output circuit 247 is a circuit for converting the image data stored in the SDRAM 237 and the recording medium 245 into a video signal to be displayed on the liquid crystal monitor 26. The liquid crystal monitor 26 is disposed on the back surface of the camera body 200. However, the liquid crystal monitor 26 is not limited to the back surface as long as the photographer can observe the image. A lens attachment / detachment detection switch 257 for detecting whether or not the interchangeable lens 100 is attached to the camera body 200 is provided in the lens attachment opening of the camera body 100. A switch for detecting the first and second strokes of the shutter release button, a switch for instructing a reproduction mode, a switch for instructing the movement of the cursor on the screen of the liquid crystal monitor 26, a switch for instructing a photographing mode, and each selected mode The various switches 255 such as an OK switch for determining etc. and the lens attachment / detachment detection switch 257 are connected to the data bus 261 via the switch detection circuit 253. The lens attachment / detachment switch 257 is a known mechanical switch that detects attachment / detachment of the lens, but is not limited thereto. For example, the lens attachment / detachment switch 257 is detected by communicating with a photoelectric detection switch or a CPU in the lens. In other words, any object that can detect the attached / detached state of the lens may be used.

Next, a flow of power-on reset when the power switch of the camera body is turned on will be described with reference to FIG. It is determined whether a power switch (not shown) of the camera body is turned on (S1). If the result of determination is that the power switch is off, processing advances to step S3 and a sleep state is entered. In this sleep state, interrupt processing is performed only when the power switch is turned on, and power switch-on processing in the next step S5 is performed. Until the power switch is turned on, operations other than power switch interrupt processing are stopped to prevent power consumption. In step S1, when the power switch is on, the process proceeds to step S5 to perform power switch on processing. In step S5, an initial value resetting operation such as various flags is performed for the electrical system of the camera body, and a resetting operation such as initial position setting is performed for the mechanical system.

When the power switch-on process is finished, it is next determined whether or not the live view mode is set (S7). It is detected whether or not the live view is set by various buttons for setting the display mode of the camera body. If the live view mode is not set, the process proceeds to the information display mode (S9), while the live view is set. If the mode is set, the process proceeds to the live view mode (S11). The information display mode is a mode in which shooting information and the like of the camera are displayed on the liquid crystal monitor 26, and the shooting information can be set and changed. The live view mode is a mode in which the subject image captured by the CCD 221 is displayed on the liquid crystal monitor 26.

When the information display mode or the live view mode ends, it is determined again whether or not the power switch is off (S13). If it is on, the process returns to step S7 to repeat the above steps. If the power switch is off, the process proceeds to step S15 to perform various processes for power off. At the time of power-off, setting is performed in the cam area b of the shutter charge cam 353 and the mirror charge cam 355.

Next, the flow of the live view mode in step S11 will be described with reference to FIG. When the live view mode is entered, first, photometry / exposure amount calculation is performed (S21). Here, since it is still in the cam region d (see FIG. 5) and the movable reflection mirror 201 is in the reflection position, the photometric element 211 measures a part of the subject light beam guided from the movable reflection mirror 201, and this photometry Based on the value, the body CPU 229 calculates an exposure value such as a shutter speed and an aperture value. Subsequently, initial setting for performing live view is performed (S22). In this initial setting, power is supplied to the CCD 221, live view display conditions are set in order to keep the brightness of the live view display on the liquid crystal monitor 26 appropriate, and the mirror up operation of the movable reflecting mirror 201 is also performed. The latter will be described later with reference to FIG. The live view is started in the live view initial setting.

Next, it is determined whether the release button 21 is half-pressed, that is, whether 1R is on (S23). If the result of determination is that it is on, processing advances to step S25, and an automatic focus adjustment (AF) subroutine is executed. In this subroutine, automatic focus adjustment and photometry are performed while the subject image is live-viewed on the liquid crystal monitor 26. This automatic focus adjustment and photometry operation are carried out through the cam area e to the cam area d, in which the movable reflection mirror 201 is lowered to the reflection position and photometry is performed by the photometry element 211 and guided by the sub mirror 203. A distance measuring operation is performed by the distance measuring circuit 217 based on the subject light flux.

When the automatic focus adjustment (AF) in step S25 ends, it is subsequently determined whether or not the release button 21 has been fully pressed, that is, whether or not 2R is on (S27). As a result of the determination, if 2R is on, the process proceeds to step S29, and the photographing operation is executed. This photographing operation subroutine will be described later with reference to FIG. When the shooting operation is completed, the process returns to the initial setting of the live view in step S22, and the above steps are repeated. Returning to step S27, if 2R is off, the process proceeds to step S31 to determine whether 1R is on. If the release button 21 is half-pressed but not fully pressed, a standby state is made in which the determinations in steps S27 and S31 are made. When the photographer's hand is released from the release button 21, the process returns to step S23 and the above steps are repeated.

Returning to step S23, if 1R is off, the process proceeds to step S33, where the operation button <switches the display mode, that is, the display of the subject image in the live view to the optical display in the viewfinder optical system (not shown). It is determined whether or not switching has been performed. If the display mode is switched as a result of the determination, in step S35, in order to stop the live view display of the subject image on the liquid crystal monitor 26, processing such as power supply stop of the CCD 221 is performed. The live view display is started in the initial setting of the live view in step S22, and until the live view display is stopped in step S35, the liquid crystal monitor 26 continuously displays the image data repeatedly acquired by the CCD 221. Live view display is made. Subsequently, in step S37, the shutter 213 and the movable reflecting mirror 201 are initialized. In the live view, the movable reflection mirror 201 is moved to the up position (reflection position), but the subject image is observed with the optical finder, and the liquid crystal monitor 26 displays the shooting information. This is a process for returning. In this initialization, the MS motor 301 is driven until the aforementioned mirror charge cam 353 and shutter charge cam 355 reach the cam area d.

Returning to step S33, if the display mode has not been switched, the process proceeds to step S41, where the state of a lens attachment / detachment detection switch (not shown) is detected to determine whether or not the taking lens has been detached. If the result of determination is that the lens has been removed, the process proceeds to step S43 to perform lens removal processing. Since the shutter 213 is a normally open type, there is no possibility that a member that covers the CCD 221 disappears when the taking lens is removed, and dust or the like may be attached, and the CCD 221 is directly exposed to the outside world. From the meaning, the shutter 213 is closed and the movable reflecting mirror 201 is lowered. When the lens detachment process is completed, the process returns to step S23 and the above steps are repeated.

Returning to step S41, if the taking lens is not detached, it is determined whether the taking lens is attached by detecting the state of the lens attachment / detachment detection switch. If the result of determination is that a photographic lens has been attached, processing proceeds to step S47 and lens attachment processing is performed. As described above, when the lens is removed, the shutter 213 is closed, but when the photographing lens is attached, the shutter 213 is opened. When the lens mounting process ends, the process returns to step S22, and the above steps are repeated.

Next, the live view initial setting in step S22 will be described in detail with reference to the flowchart shown in FIG. Before performing live view, the mirror charge cam 353 and the shutter charge cam 355 are in the cam area d (standby area). Upon initialization of the live view, the MS motor 301 moves to the cam area f in which the live view is performed. Drive. First, the MS motor 301 is rotated to drive the mirror charge cam 353 and the shutter charge cam 355 from the cam area d to the cam area e (S51). During this time, the mirror drive lever 341 moves from the position shown in FIG. 2D toward the position shown in FIG. 2E, and the movable reflecting mirror 201 is moved to the up (retracted) position by the spring force of the mirror drive spring 343. Rotate. Further, since the cam surface 355a of the shutter cam 355 does not change and remains at the top dead center, it remains at the position shown in FIGS. 2B and 2A and maintains the shutter charge state. When the f region is reached, the f detection becomes L level (S53), and the rotation of the MS motor 301 is stopped (S55). As a result, the movable reflecting mirror 201 is in the up (retracted) position, and the shutter 213 remains in the shutter charge state. As described above, since the shutter 213 is a normally open shutter, the shutter 213 remains open in a normal state, and no shutter opening operation for performing live view is particularly necessary.

In this state, since the movable reflecting mirror 201 is in the retracted position and the shutter 213 remains open, a subject image is formed on the CCD 221, and image information is read from the CCD 221 as an imager. Start (S57). Based on the read image information, live view display is performed on the liquid crystal monitor 26 (S59). In order to perform live view display, image information is repeatedly read from the CCD 221 (for example, 30 frames / second) and displayed as a moving image.

Next, the photographing operation in step S29 will be described in detail using the flowchart shown in FIG. As described above, this subroutine acquires a still image based on the output from the CCD 221 and records it on the recording medium 245 when the release button 21 is fully pressed during live view. The live view is performed in the cam area f, and when moving to the shooting operation, the front and rear curtain magnets of the shutter 213 are attracted and held, and then the mirror charge cam 353 and the shutter charge cam 355 are directly placed in the cam area g. What is necessary is just to drive. As described above, since the shutter 213 is a normally open type, it is in a shutter open state, and therefore is temporarily closed for exposure time control. Further, since the movable reflecting mirror 201 is at the retracted position, it is sufficient that the position is maintained.

First, power is supplied to the shutter front curtain and rear curtain holding magnet Mg to hold the front curtain and rear curtain (S71). Thereafter, driving of the MS motor 301 is started (S73). By this drive, the drive starts from the cam area f toward the cam area g. Since the cam surface 353a of the mirror charge cam 353 is not changed between the cam region f and the cam region g, the movable reflecting mirror 201 maintains the retracted position as it is, but the cam surface 355a of the shutter charge cam 355 is dead from the top dead center. The shutter front curtain changes from the open position to the closed position in response to the change. At approximately the same time, when the g detection switch for detecting the transition from the cam region f to the cam region g detects the L level (S75), the MS motor 301 stops driving (S77).

In this state, the movable reflecting mirror 201 is retracted from the photographing optical path, and the shutter 213 is ready for exposure, so that the photographing operation is started (S79). First, energization of the magnet Mg holding the shutter front curtain is stopped, and the travel of the shutter front curtain is started. When the time corresponding to the shutter speed calculated in advance elapses, the running of the shutter rear curtain is started. If the time for the trailing curtain to end after the shutter trailing curtain starts running, an instruction to read out the image signal is issued from the CCD 221 (S81). Subsequently, the MS motor 301 is driven (S82), and the cam region g is shifted to the cam region a.

When moving from the cam area g to the cam area a, the cam surface 353a of the mirror charge cam 353 becomes a lift area, and the mirror charge lever 351 rotates to perform the charging operation of the movable reflecting mirror 201. When moving from the cam area a to the cam area b, the g detection switch rises from the L level to the H level (S83). When this H level signal is detected, the driving of the MS motor 301 is stopped (S84). In this state, it waits for the reading of the image signal from the CCD 221 to be completed (S85), and when the reading is completed, the MS motor 301 is driven again (S86).

As described above, the reading of the image signal from the CCD 221 is performed between steps S81 and S85, which are the region g, the region a, and the region b. In these regions, the shutter 213 remains closed, and the subject light flux is not received by the CCD 221, so that no noise is generated in the image signal read from the CCD 221. When reading of the image signal is completed, display is performed on the liquid crystal monitor 26 for a predetermined time based on the read image signal.

In step S86, when the MS motor 301 is driven to move from the cam area b to the cam area c, the cam surface 355a of the shutter charge cam 355 becomes a lift area, and the shutter charge lever 361 rotates to perform the charging operation of the shutter 213. Do. When the shutter 213 is charged in the cam area c, the shutter 213 changes from the closed state to the open state. When entering the cam area d from the cam area c, the d detection switch detects the L level (S87), and the MS motor 301 stops driving (S88). Subsequently, image data based on the read image signal is recorded on the recording medium 245 (S89). When the shooting operation subroutine is completed, the process returns to the initial setting of the live view in step S22. In this subroutine, the cam area d is shifted to the f area, and the live view is resumed.

As described above, in this embodiment, the readout of the image signal after imaging is performed with the shutter 213 closed, and the charging operation (opening operation) of the shutter 213 is performed after the completion of the readout. That is, the camera enters the cam area g where the photographing operation is performed (timing t0 in FIG. 11), and the shutter front curtain and the rear curtain are run. When the exposure operation is completed, reading of the image signal from the CCD 221 is subsequently started (FIG. 11). T1 timing). When the reading of the image signal is completed (timing t2 in FIG. 11), the driving of the MS motor 301 is started (timing t3 in FIG. 11), and the shutter 213 is charged in the cam region c.

As described above, in the first embodiment of the present invention, the normal open type shutter 213 is used, and the readout of the image signal of the CCD 221 is started in the shutter closed state after the imaging operation is completed, and the readout of the image signal is completed. Until then, the shutter charging operation, that is, the opening operation is prohibited. Therefore, it is possible to prevent a problem that subject light is incident on the image sensor during image reading and noise is generated.

In the first embodiment of the present invention, a normally open type shutter 213 is used, and a power off region (cam region b) and a live surface are respectively provided on the cam surface 353a of the shutter charge cam 353 and the cam surface 355a of the mirror charge cam 355. A view area (cam area f) and a photographing area (cam area g) are provided, and when the power is turned on, the shutter charge cam 255 is driven from the power off area to the standby area, thereby performing the shutter 213 opening operation and shutter charging operation. As described above, it is easy to shift to the live view and the photographing operation can be performed quickly.

In the first embodiment of the present invention, the two cams, the mirror charge cam 353 and the shutter charge cam 355, are used. However, the present invention is not limited to this. For example, a single cam can be used for mirror charge and shutter charge. You may make it divide for use. In addition, the cam rotates only in one direction except for the reciprocation between the standby area (cam area d) and the live view area (cam area f), but the cam area f of the shutter charge cam 255 and the cam You may make it perform forward / reverse rotation by loosening the cam shape between the area | regions g. Furthermore, although the cam surface for performing the closing operation of the shutter front curtain is the live view area (cam area f), it can also be the shooting area (cam area g).

In the present embodiment, the camera performs live view. However, the present invention is not limited to this, and the present invention can be applied to any camera that employs a normally open type shutter even when observing a subject image with an optical viewfinder.

Next, a second embodiment of the present invention will be described. In the first embodiment of the present invention, the movable mirror 201 is a total reflection mirror, and when performing live view display, the movable mirror 201 is retracted from the optical path of the photographing lens. However, in the second embodiment, the movable mirror 201 is retracted. Is configured with a half mirror, and when performing live view display, the subject light flux transmitted through the movable half mirror 1201 is used.

First, an overall configuration mainly including an electric system of a digital single-lens reflex camera in the second embodiment will be described with reference to FIG. Inside the lens barrel 10, as in the first embodiment, lenses 101 and 102 for focus adjustment and focal length adjustment, an aperture 103 for adjusting the aperture, a lens 101 and an optical for driving the lens 102. A system driving mechanism 107, an aperture driving mechanism 109 that drives the aperture 103, and a lens CPU 111 that controls these are provided. Since the configuration and operation are the same as those of the first embodiment, detailed description thereof is omitted.

In the mirror box in the camera body 20, a movable reflecting mirror (hereinafter referred to as an operating half mirror) 1201 having a characteristic of transmitting a part of the light flux that has passed through the lenses 101 and 102 is disposed. The movable half mirror 1201 is driven by a movable mirror drive mechanism 1215 and can rotate about an axis 1201a about a vertical axis in the drawing. When the movable half mirror 1201 is at a reflection position inclined at 45 degrees with respect to the optical path of the lenses 101 and 102 (the position indicated by the solid line in FIG. 12), a part of the subject luminous flux (for example, 30%) is reflected, Guided to photometric sensor 1217. Further, the remainder (for example, 70%) of the subject luminous flux passes through the movable half mirror 1201 and is guided in the direction of the CCD 221. When the movable half mirror 1201 is substantially parallel to the optical path of the lenses 101 and 102 and is at a retracted position (a position indicated by a two-dot chain line in FIG. 12) that does not block the subject light beam, all of the subject light beam is guided to the CCD 221. In the present embodiment, the center of rotation of the movable half mirror 1201 is the lower side in the mirror box, but is not limited thereto, and may be the upper side, and may be rotated in parallel to the paper surface on either the left or right side. Of course, it does not matter if it is a dynamic center.

The distance measuring / photometric sensor 1217 is arranged above the mirror box in the camera body 20 at a position where the light beam reflected by the movable half mirror 1201 is guided, and includes a distance measuring sensor and a photometric sensor. Has been. The photometric sensor is composed of a multi-division photometric element that divides and measures a subject image, and the distance measuring sensor is a sensor for measuring a distance by a TTL phase difference method. The output of the distance measurement / photometry sensor 1217 is sent to the distance measurement / photometry processing circuit 1219. The distance measurement / photometry processing circuit 1219 outputs an evaluation photometric value based on the output of the photometry sensor, and measures the focus shift amount of the subject image formed by the lenses 101 and 102 based on the output of the distance measurement sensor. To do. Note that the distance measuring sensor and the photometric sensor may be configured separately or integrally.

A focal plane type shutter 1203 for exposure time control and shading of the CCD 221 is disposed behind the movable half mirror 1201 and on the optical axis of the lenses 101 and 102 and on the photographing optical path. The shutter 1203 is driven and controlled by a shutter drive mechanism 213. The shutter 1203 is a normal open type focal plane shutter, similar to the shutter 213 of the first embodiment.

A dustproof filter 1205 is disposed behind the shutter 1203. This is because dust generated in the mount opening of the camera body 20 and inside the body adheres to the CCD 221 and the optical element, and the shadow of the dust is copied to the subject image. It is a filter to prevent it from becoming unsightly. A piezoelectric element 1207 is fixed to the entire periphery or a part of the peripheral edge of the dustproof filter 1205, and this piezoelectric element 1207 is connected to the dustproof filter driving circuit 1211 and driven by this circuit. The piezoelectric element 1207 is driven by a dust filter driving circuit 1211 so that the dust filter 1205 vibrates with a predetermined ultrasonic wave, and dust attached to the front surface of the dust filter 205 is removed using the vibration. In addition, as long as dust attached to the image pickup device itself such as a CCD or an optical element disposed on the front side of the image pickup device can be removed, it is not limited to one using ultrasonic vibration as in the present embodiment. Of course, it may be appropriately replaced with various methods such as a method of blowing off by an air flow using an air pump or a method of collecting and removing dust using static electricity.

An infrared cut filter 1209 for cutting an infrared light component from the subject light beam is disposed behind the dust filter 1205, and an optical low-pass filter 1210 for removing a high frequency component from the subject light beam is disposed behind the dust filter 1205. Has been. A CCD 221 serving as an image sensor is disposed behind the optical low-pass filter 1210, and the subject image formed by the lenses 101 and 102 is photoelectrically converted into an electrical signal. The dustproof filter 1205, the infrared cut filter 1209, the optical low-pass filter 1210, and the CCD 211 are integrally housed in a sealed package (not shown), and are configured so that dust does not enter the package. In the present embodiment, a CCD is used as an image sensor. However, the present invention is not limited to this, and a CMOS (Complementary Metal Oxide) is used.
Needless to say, a two-dimensional imaging device such as Semiconductor) can be used.

The CCD 221 is connected to the image sensor drive circuit 1223 and is driven and controlled by a control signal from the input / output circuit 239. A photoelectric analog signal output from the CCD 221 is amplified by the image sensor driving circuit 1223 and subjected to analog-digital conversion (AD conversion). The image sensor driving circuit 1223 is connected to the image processing circuit 227, and the image processing circuit 227 performs digital amplification (digital gain adjustment processing) of digital image data, color correction, gamma (γ) correction, contrast correction, monochrome / color mode. Various image processing such as processing and live view 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. A communication circuit 241, a recording medium control circuit 243, a flash memory control circuit 247, and a switch detection circuit 253 are connected.

The image processing circuit 227, body CPU 229, compression circuit 231, video signal output circuit 247, SDRAM 236, communication circuit 241, recording medium control circuit 243, flash memory 233, and switch detection circuit 253 in the ASIC 271 have the same configuration as in the first embodiment. Therefore, detailed description is omitted. Further, the liquid crystal monitor driving circuit 249, SDRAM 237, recording medium 245, flash memory 235, and other various switch circuits 255 connected to these circuits are the same as those in the first embodiment, and therefore, detailed description thereof is also provided. Is omitted.

In the first embodiment, only the liquid crystal monitor 26 is used as a through image display device. However, in the second embodiment, a liquid crystal monitor is provided on the back of the camera body and in the viewfinder, and the liquid crystal monitor 26 of the first embodiment is provided. The rear liquid crystal monitor 26 having the same configuration as in FIG. The in-viewfinder liquid crystal monitor 29 is disposed at a position that can be observed by the photographer through the viewfinder eyepiece 33. Similar to the rear liquid crystal monitor 26, the liquid crystal monitor 29 is not limited to the liquid crystal and may be another display device. Note that only the rear liquid crystal monitor 26 may be used for observation of the subject image, and the finder eyepiece 33 and the finder liquid crystal monitor 29 may be omitted.

The function of the input / output circuit 239 is the same as that of the first embodiment. The dustproof filter driving circuit 211, the shutter driving mechanism 213, the movable mirror driving mechanism 215, the mirror movement detection switch 216, and the distance measuring / photometric processing circuit. 219, connected to the image sensor driving circuit 223, and controls data input / output with each circuit such as the body CPU 229 via the data bus 261. Further, the power switch 257 is a switch that is turned on / off in conjunction with a power switch lever for controlling the power supply of the camera body 20 and the lens barrel 10.

The shutter / mirror drive unit of the second embodiment is the same as the shutter / mirror drive unit (FIGS. 2 and 3) of the first embodiment. The shape of the mirror charge cam 353 and the shutter charge cam 355 is the same as that of FIG. As shown in FIG. As for the shape of the mirror charge cam 353 and the shutter charge cam 355, the cam region a to the cam region d and the cam region g of the first embodiment have the same shape. The cam area e and the cam area f of the shutter charge cam 355 have the same shape as the cam area h of the second embodiment. The difference is that the cam area e which is the transition area of the mirror charge cam 353 of the first embodiment and the cam area f which is the live area are different from the cam area h which is substantially the top dead center in the second embodiment. It is a point.

The only difference in this area is that in the first embodiment, the movable mirror 201 is composed of a reflection mirror whose center is a half mirror, and in the live view area, the movable reflection mirror 201 is made of lenses 101 and 102. It was necessary to retract from the optical axis. In contrast, in the second embodiment, since the movable half mirror 1201 whose entire surface is a half mirror is employed, the transmitted light of the movable half mirror 1201 can be used in the live view area, and the movable half mirror 1201 is retracted. This is because there is no need. Therefore, the mirror charge cam 353 and the shutter charge cam 355 have the same shape in the standby area d and the live view area h.

Next, the effect | action at the time of the imaging | photography operation | movement in 2nd Embodiment comprised in this way is demonstrated using FIG. In the standby area (cam area d) or live view area (cam area h), when the release button 21 is fully pressed and the photographing operation starts (timing t11 in FIG. 15), the MS motor 301 is turned on and the mirror charge cam 353 is turned on. The shutter charge cam 355 rotates toward the cam region g. Accordingly, the movable half mirror 1201 is driven from the down position to the up position, that is, from the position inserted in the photographing optical path to the retracted position, and the shutter 1203 is driven from the charged state to the reset state, that is, from the open state to the closed state. Is done. Further, the shutter front curtain magnet and the rear curtain magnet start the operation of attracting the shutter curtain of the shutter 1203.

When the mirror charge cam 353 and the shutter charge cam 355 reach the cam area g, the g detection changes from the H level to the L level (timing t12). When it is detected that the g detection has changed to the L level, the MS motor 301 stops driving, and at time t13, the suction and holding of the shutter front curtain by the magnet is released, and the shutter front curtain starts running. When the time corresponding to the manually set shutter speed or the exposure-calculated shutter speed has elapsed (timing t14), the suction and retention of the shutter rear curtain by the magnet is released, the shutter rear curtain starts running, and exposure seconds Control the time.

At timing t15 after a sufficient time has elapsed for the trailing curtain to end, reading of image signals from the CCD 221 is started. Further, the MS motor 301 is driven to start from the cam region g toward the cam region a. When the cam region b is entered at timing t16, the g detection changes from the L level to the H level. The drive of the motor 301 is stopped. This is because the image signal is read while the shutter 1203 is in the closed state. When the reading of the image signal from the CCD 221 is completed (timing t17), the driving of the MS motor 301 is resumed. When entering the cam area d (timing t18), the d detection is changed from the H level to the L level. Stop driving.

As described above, the reading of the image signal from the CCD 221 is performed between the timings t15 and t17, and this is during the region g, the region a, and the region b as in the first embodiment. In these areas, the shutter 1203 remains closed and does not receive the subject luminous flux on the CCD 221, so that no noise is generated in the image signal read from the CCD 221.

In the second embodiment, since the subject light flux is guided to the distance measurement / photometry sensor 1217 and the CCD 221 using the movable half mirror 1201, live view display is performed based on the image signal of the CCD 221, and Distance measurement and photometry can be performed in parallel using the output of the photometric sensor 1217, which is very convenient. In the first embodiment, when performing distance measurement, the live view area must be driven to the standby area. In the second embodiment, since a half mirror is used, such driving is not performed. No longer needed.

In the shooting operation of the second embodiment, the movable half mirror 1201 is retracted during the shooting operation for acquiring a still image. For this reason, a decrease in the amount of transmitted light through the movable half mirror 1201 can be eliminated, the amount of subject light can be increased in acquiring a still image, and shooting at a high shutter speed is possible. Further, when the imaging operation is completed, the movable half mirror 1201 is returned at timing t15. Therefore, when the release button 21 is half-pressed again after shooting, photometry and distance measurement are performed in parallel with the through image display. be able to.

As described above, in the first and second embodiments, the shutter is closed until the reading of the subject image signal picked up by the CCD 221 is completed. Therefore, noise is generated during reading and is superimposed on the image signal. There is no risk of unsightly images.

In the first and second embodiments, since the shutters 213 and 1203 are so-called normal open shutters that are opened in a charged state, the shutter opening operation is not necessary when performing live view display. Live view display can be performed easily.

In the first and second embodiments of the present invention, the two cams, the mirror charge cam 353 and the shutter charge cam 355, are used. However, the present invention is not limited to this, and for example, a single cam is used for mirror charging. And shutter charge may be divided. Of course, a cam hole may be used instead of the cam surface.

Further, in the first and second embodiments of the present invention, the image sensor is one of the CCDs 221, but it is needless to say that the present invention can also be applied to a camera that performs live view display by switching the outputs of a plurality of image sensors. It is. Further, the movable reflecting mirror 201 switches the optical path between the finder optical system and the image sensor, but is not limited to this, and is configured to switch between, for example, an image sensor for image recording and an image sensor for object image observation. Of course, the present invention can be applied.

In the first and second embodiments of the present invention, the present invention is applied to a general digital camera. However, the present invention is not limited thereto, and may be a digital camera in various devices such as a portable device, a microscope, Of course, the present invention can also be applied to a dedicated digital camera attached to various devices such as binoculars. The present invention can be applied to any digital camera that displays a shooting target on a monitor device in a live view.

2 is a block diagram illustrating a schematic configuration of an internal mechanism of the digital single-lens reflex camera according to the first embodiment of the present invention, in which (A) illustrates the internal configuration along the optical axis direction of the photographing lens, and (B) illustrates the camera body 200. FIG. It is a block diagram which shows the internal structure seen from the front direction. 1A and 1B are diagrams showing a shutter and a movable reflecting mirror of a digital single lens reflex camera according to a first embodiment of the present invention, wherein FIG. 1A is a perspective view of the shutter, FIG. 1B is a front view of the shutter, and FIG. FIG. 4D is a perspective view of the movable reflecting mirror, FIG. 4D is a diagram illustrating a mirror-down state of the movable reflecting mirror, and FIG. 5E is a diagram illustrating a mirror-up state of the movable reflecting mirror. It is a partial detail drawing of the shutter mirror drive unit of the digital single-lens reflex camera concerning 1st Embodiment of this invention. 2A and 2B are diagrams illustrating a cam area of the digital single-lens reflex camera according to the first embodiment of the present invention, in which FIG. 3A illustrates a mirror charge cam, and FIG. 3B illustrates a cam area of a shutter charge cam. It is a development view of the cam area of the digital single-lens reflex camera according to the first embodiment of the present invention. 1 is a block diagram mainly showing an overall configuration of an electric system of a digital single-lens reflex camera according to a first embodiment of the present invention. It is a flowchart of the power-on reset of the digital single-lens reflex camera in 1st Embodiment of this invention. It is a flowchart of the live view display of the digital single-lens reflex camera in 1st Embodiment of this invention. It is a flowchart of the live view initial setting of the digital single-lens reflex camera in 1st Embodiment of this invention. It is a flowchart of imaging | photography operation | movement of the digital single-lens reflex camera in 1st Embodiment of this invention. It is a time chart at the time of imaging | photography of the digital single-lens reflex camera in 1st Embodiment of this invention. It is a block diagram which mainly shows the whole structure of the electric system of the digital single-lens reflex camera which concerns on 2nd Embodiment of this invention. It is an expanded view of the cam area | region of the digital single-lens reflex camera concerning 2nd Embodiment of this invention. 4A and 4B are diagrams showing a cam area of a digital single-lens reflex camera according to a second embodiment of the present invention, where FIG. 5A shows a mirror charge cam, and FIG. 5B shows a cam area of a shutter charge cam. It is a time chart at the time of imaging | photography of the digital single-lens reflex camera in 2nd Embodiment of this invention.

Explanation of symbols

21 Release button 26 LCD monitor (Back LCD monitor)
29 LCD in the viewfinder 33 Viewfinder 100 Lens barrel 200 Camera body 201 Movable reflection mirror 203 Sub mirror 213 Focal plane shutter 213b Shutter set lever 221 CCD
229 Body CPU
279 CCD in the viewfinder
227 Image processing circuit 285 CCD switching circuit 301 MS motor 303 shutter / mirror drive unit 341 mirror drive lever 353 mirror charge cam 355 shutter charge cam 357 cam gear 361 shutter charge lever 1201 movable half mirror 1203 focal pre-shutter

Claims (10)

Imaging means capable of photographing the light flux from the photographing optical system;
A reflecting member movable between an insertion state capable of reflecting the light beam from the photographing optical system and a retracted state retracted from the light beam from the photographing optical system;
A shutter unit that is disposed between the imaging optical system and the imaging means and is open in a charged state;
Comprising
A digital camera characterized in that charging operation of the shutter unit is prohibited during reading of image data from the imaging means. The digital camera according to claim 2, wherein the shutter unit is a focal plane shutter. Imaging means capable of photographing the light flux from the photographing optical system;
A reflecting member movable between an insertion state capable of reflecting the light beam from the photographing optical system and a retracted state retracted from the light beam from the photographing optical system;
A shutter unit that is disposed between the photographing optical system and the imaging means and is in an open state in a charged state;
A cam member capable of driving the reflecting member and the shutter unit;
Comprising
In the first cam section used after exposure, the reflection member is inserted, and in the second cam section used after exposure, the shutter unit is charged. From the first cam section to the second cam section. A digital camera characterized in that the transition to is permitted only after completion of reading of image data of the imaging means.   5. The digital camera according to claim 4, wherein the shutter unit is in an open state in a charged state and is in a light shielding state in an exposure operation complete state. An image sensor;
A reflection mirror that is movable to a position that reflects the subject luminous flux and a retreat position that is out of the subject luminous flux;
A shutter mechanism that is disposed between the reflecting mirror and the image pickup device and has a shutter curtain in an open state in a charging completion state;
Comprising
Prior to the image pickup operation by the image pickup device, the reflection mirror is moved to the retracted position, and after the image pickup operation is finished, the reflection mirror is moved to the reflection position, and the image signal is read from the image pickup device following the image pickup operation. A digital camera characterized in that a charging operation of the shutter mechanism is executed after the operation is completed. An image sensor that receives a subject luminous flux and outputs a subject image signal;
A shutter mechanism that is disposed between the photographic lens and the imaging element and in which the shutter curtain is in an open state in a charging completion state;
Monitor means for displaying a subject image as a moving image based on the subject image signal output from the image sensor;
Control that resets the shutter mechanism prior to the image pickup operation by the image pickup device, and executes the charge operation of the shutter mechanism after the image pickup operation ends and after the image signal read-out operation from the image pickup device ends. Means,
A digital camera comprising: A reflection mirror that is movable to a position that reflects the subject luminous flux and a retracted position that is out of the subject luminous flux; and the control means moves the reflective mirror to the withdrawal position prior to the imaging operation, and The digital camera according to claim 6, wherein the reflecting mirror is moved to the reflecting position after the imaging operation is finished and before the shutter mechanism is charged.   The digital camera according to claim 7, wherein the reflection mirror is a half mirror or a total reflection mirror. Imaging means for receiving a light beam from the photographing optical system and outputting a subject image signal;
A reflecting member movable between an insertion state capable of reflecting the light beam from the photographing optical system and a retracted state retracted from the light beam from the photographing optical system;
A shutter unit that is disposed between the photographing optical system and the imaging means and is in an open state in a charged state;
A driving member capable of driving the reflecting member and the shutter unit;
Comprising
In the first section after the imaging operation by the imaging means, the reflecting member is moved to the reflective insertion state, and in the second section following the first section, the shutter unit is charged, and the first unit is charged. A digital camera characterized in that the transition from the section to the second section is permitted only after the reading of the subject image signal is completed.   The drive member has a first cam interlocked with the reflecting member and a second cam interlocked with the shutter unit, and the first cam and the second cam are a first section and a second section, respectively. The digital camera according to claim 9, further comprising a cam surface corresponding to.