JP2017122802A - Imaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging device capable of further shortening release time lag without influencing a photometric value by controlling operation of a second mirror holder during mirror-up operation.SOLUTION: After focus detection operation has ended, an imaging device makes a holder 504 holding a mirror 503 turn toward a holder 502 holding a mirror 501 and wait in a standby position opened at only a prescribed angle to the holder 502 according to a user-selected photometric mode among a plurality of photometric modes, and pushes up the holder 502 to cause the holder 504 to move from the standby position toward a mirror-up position by turning the holder 504 from the standby position toward the mirror-up position on the basis of an imaging instruction by an imaging element. After imaging has ended, the imaging device pushes down the holder 502 to cause the holder 504 to move to the mirror-down position by turning the holder 504 from the mirror-up position to the standby position, and turns the holder 504 from the standby position to the mirror-down position when a focus detection operation instruction disappears.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an imaging apparatus such as a single-lens reflex camera, and more particularly to a technique for controlling the operation of a quick return mirror.

  An imaging apparatus such as a single-lens reflex camera has a quick return mirror mechanism having a main mirror holder that holds a main mirror composed of a half mirror, and a sub mirror holder that holds the sub mirror and is rotatably supported with respect to the main mirror holder Is provided. The quick-return mirror mechanism guides the subject light flux that has entered the optical path of the shoot (mirror down) and passed through the photographic optical system to the finder optical system during viewfinder observation, and retracts (mirrors up) from the photographic optical path during shooting. The subject light flux that has passed through the optical system is guided to the image sensor. In viewfinder observation, the subject luminous flux that has passed through the main mirror is reflected by the sub mirror and guided to the focus detection unit (Patent Document 1).

JP 09-274249 A

  However, in Patent Document 1, since the main mirror holder has a mechanism for pulling up the sub mirror holder during the mirror up operation, the inertia force of the sub mirror holder works when the main mirror holder performs the mirror up operation. For this reason, there is a limit to the mirror-up operation speed, which hinders the reduction of the release time lag.

  Therefore, the present invention provides an imaging apparatus that can further reduce the release time lag without affecting the photometric value by controlling the operation of the second mirror holder during the mirror-up operation. Objective.

  In order to achieve the above object, the image pickup apparatus of the present invention can move between a first position holding the first mirror and being in the photographing optical path and a second position retracting from the photographing optical path. A first mirror holder and a first mirror holder rotatably attached to the first mirror holder, holding the second mirror and retreating from the photographing optical path and a third position located in the photographing optical path A second mirror holder that is movable between a fourth position and the second mirror holder while the first mirror holder is located at the first position during viewfinder observation. Is located at the third position, the subject light flux that has passed through the photographing optical system is reflected by the first mirror and guided to the viewfinder optical system, and the subject light flux that has passed through the first mirror is reflected by the second mirror. Reflected by the mirror and guided to the focus detection means At the time of shooting, the first mirror holder moves to the second position, and the second mirror holder moves to the fourth position, so that the subject light flux that has passed through the shooting optical system is imaged. And the second mirror holder is driven between the third position and the fourth position, and the second mirror holder is moved from the third position to the fourth position. By moving, the driving means for moving the first mirror holder from the first position to the second position, the photometry means having a plurality of photometry modes, and the focus by the first operation of the operation member. An instruction means for instructing a focus detection operation by the detection means, an instruction means for instructing an image pickup by the imaging element by a second operation of the operation member, and an end of the focus detection operation by an instruction based on the first operation of the instruction means rear The second mirror holder at the third position is rotated by the driving means toward the first mirror holder at the first position, and the second mirror holder is moved to the plurality of photometry. According to the photometric mode selected by the user from among the modes, the second mirror of the instruction means after the focus detection operation is made to stand by at a standby position opened by a predetermined angle with respect to the first mirror holder. Based on an instruction for imaging by the imaging element based on the operation, the driving means rotates the second mirror holder from the standby position toward the fourth position, thereby moving the first mirror holder to the first position. And a control means for moving the first position to the second position.

  In addition, the imaging apparatus of the present invention is a first mirror holder that can move between a first position that holds the first mirror and is located in the photographing optical path and a second position that retreats from the photographing optical path. And a third position that is rotatably attached to the first mirror holder and that holds the second mirror and is located in the photographing optical path, and a fourth position that is retracted from the photographing optical path. A second mirror holder capable of moving between the first mirror holder and the third mirror holder at the third position, when the viewfinder is observed. The subject light flux that has passed through the photographing optical system is reflected by the first mirror and guided to the finder optical system, and the subject light flux that has passed through the first mirror is reflected by the second mirror. At the time of shooting The mirror holder is moved to the second position, the second mirror holder is moved to the fourth position, and the mirror unit that guides the subject light flux that has passed through the photographing optical system to the imaging device; By driving the second mirror holder between the third position and the fourth position, and moving the second mirror holder from the third position to the fourth position, A driving means for moving one mirror holder from the first position to the second position, a photometry means having a plurality of photometry modes, and a focus detection operation by the focus detection means by a first operation of the operation member. An instruction means for instructing imaging by the imaging device by a second operation of the operation member; and after the focus detection operation by an instruction based on the first operation of the instruction means is completed by the instruction means When there is an instruction for imaging by the imaging element based on the second operation, the second means is located at the third position toward the first mirror holder at the first position by the driving means. The mirror holder is rotated so that the second mirror holder is opened at a predetermined angle with respect to the first mirror holder in accordance with the photometric mode selected by the user among the photometric modes. Control means for performing photometry by the photometry means until it reaches, and for taking an image by the image sensor after the photometry is completed.

  According to the present invention, it is possible to provide an imaging apparatus that can further reduce the release time lag without affecting the photometric value by controlling the operation of the second mirror holder during the mirror up operation. it can.

1 is a block diagram showing a system configuration of a digital single-lens reflex camera which is a first embodiment of an imaging apparatus of the present invention. It is a schematic sectional side view of a digital single-lens reflex camera. It is a disassembled perspective view of a mirror unit. It is the schematic explaining operation | movement of a mirror unit. It is a figure explaining the stand-by position of a sub mirror holder according to each photometry mode when a mirror unit exists in an intermediate position. It is a flowchart explaining a camera operation when the shutter lime lag shortening mode is selected. It is a flowchart explaining the operation | movement at the time of the shutter lime lag shortening mode being selected in the digital single-lens reflex camera which is 2nd Embodiment of the imaging device of this invention. FIG. 8 is a flowchart for explaining interval photometry processing in step S707 of FIG. It is a flowchart figure explaining operation | movement when the shutter lime lag shortening mode is selected in the digital single-lens reflex camera which is 3rd Embodiment of the imaging device of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a block diagram showing a system configuration of a digital single-lens reflex camera which is a first embodiment of an imaging apparatus of the present invention.

  As shown in FIG. 1, the digital single-lens reflex camera (hereinafter referred to as a camera) according to the present embodiment has an interchangeable lens unit 210 detachably attached to the camera body 1 via a mount contact portion 21.

  First, the camera body 1 will be described. In FIG. 1, a microcomputer 100 (hereinafter referred to as MPU 100) controls the entire camera. The EEPROM 100a built in the MPU 100 stores time information of the time measuring circuit 109 and other information. Connected to the MPU 100 are a mirror drive circuit 101, a focus detection circuit 102, a shutter drive circuit 103, a video signal processing circuit 104, a switch sense circuit 105, and a photometry circuit 24 of the finder optical system 4. The MPU 100 is also connected with a display drive circuit 107, a battery check circuit 108, a time measurement circuit 109, a power supply circuit 110, and a piezoelectric element drive circuit 111, and these circuits are driven under the control of the MPU 100.

  The mirror unit 500 includes a main mirror 501 and a sub mirror 503 configured by half mirrors. The mirror unit 500 moves to a position (mirror up position) retracted from the photographing optical path during photographing and enters a photographing optical path during viewfinder observation ( Move to the mirror down position.

  The main mirror 501 reflects the subject luminous flux that has passed through the photographing lens 200 constituting the photographing optical system of the lens unit 210 at the mirror-down position of the mirror unit 500 and guides it to the finder optical system 4 and transmits a part of the subject luminous flux. To the sub mirror 503. The sub mirror 503 reflects the subject luminous flux that has passed through the main mirror 501 and guides it to the focus detection unit 31. Further, at the mirror-up position of the mirror unit 500, the subject light flux that has passed through the photographing lens 200 is guided to the image sensor 33.

  The subject light flux guided to the finder optical system 4 forms an image on the focus plate 25, and unnecessary light flux is cut by the field mask 26 and guided to the pentaprism 22. The pentaprism 22 is an optical member that converts and reflects the photographing light beam reflected by the main mirror 501 into an erect image. The user can observe the subject image from the eyepiece 18 through the pentaprism 22. The pentaprism 22 also guides part of the subject light flux to the photometric sensor 23.

  The photometric circuit 24 converts the luminance signal of each area on the observation surface based on the output of the photometric sensor 23 and outputs it to the MPU 100. The MPU 100 calculates an exposure value based on the luminance signal output from the photometry circuit 24. As will be described in detail later, for photometry, it is possible to select a photometry mode suitable for various shooting conditions.

  The mirror drive circuit 101 includes a motor, a gear train, and the like (not shown) that rotate the mirror unit 500 between a mirror up position (see FIG. 2C) and a mirror down position (see FIG. 2A). Is done.

  The focus detection unit 31 includes a field sensor, a reflection mirror, a secondary imaging lens, a diaphragm, a line sensor including a plurality of CCD sensors, and the like disposed in the vicinity of an imaging surface (not shown). The signal output from the focus detection unit 31 is supplied to the focus detection circuit 102, converted into an image signal of the subject, and then transmitted to the MPU 100. The MPU 100 performs a focus detection calculation by a phase difference detection method based on the supplied image signal of the subject.

  Then, the MPU 100 calculates the defocus amount and the defocus direction, and drives the focus lens of the photographing lens 200 to the in-focus position via the lens control circuit 201 and the AF drive circuit 202 of the lens unit 210 based on the calculation result. .

  The mechanical focal plane shutter 106 blocks the subject light beam guided to the image sensor 33 during viewfinder observation, and also at the time of imaging due to the time difference between the front blade group and the rear blade group (not shown) depending on the release signal. Operate to obtain the desired exposure time. The focal plane shutter 106 is controlled by the shutter drive circuit 103 according to a command from the MPU 100.

  The image sensor unit 114 includes an image sensor 33, a stacked piezoelectric element 112, an optical low-pass filter 113, and the like. As the image sensor 33, a CCD sensor, a CMOS sensor, a CID sensor, or the like is used. A clamp / CDS (correlated double sampling) circuit 34 performs basic analog processing before A / D conversion and can also change the clamp level. The AGC (automatic gain adjustment device) 35 performs basic analog processing before A / D conversion and can change the AGC basic level. The A / D converter 36 converts the analog signal output from the image sensor 33 into a digital signal.

  The infrared cut filter 32 is formed in a substantially rectangular shape, and cuts unnecessary infrared light of the subject luminous flux incident on the image sensor 33. The surface of the infrared cut filter 32 is covered with a conductive material in order to prevent foreign matter from adhering. The optical low-pass filter 113 is configured by laminating and laminating a plurality of birefringent plates and phase plates made of quartz, and further laminating an infrared cut filter. The stacked piezoelectric element 112 is vibrated by the piezoelectric element driving circuit 111 that has received a command from the MPU 100, and the vibration is transmitted to the optical low-pass filter 113.

  The video signal processing circuit 104 performs general image processing by hardware such as gamma / knee processing, filter processing, and monitor display information synthesis processing on digital image data. The color image data for monitor display output from the video signal processing circuit 104 is displayed on the monitor 19 via the monitor drive circuit 115.

  Further, the video signal processing circuit 104 can also store image data in the buffer memory 37 through the memory controller 38 in accordance with an instruction from the MPU 100. Further, the video signal processing circuit 104 has a function of performing image data compression processing such as JPEG. The video signal processing circuit 104 can also store image data once in the buffer memory 37 and sequentially read out unprocessed image data through the memory controller 38 when continuous shooting such as continuous shooting is performed. is there. Accordingly, the video signal processing circuit 104 can sequentially perform image processing and compression processing regardless of the speed of the image data output from the A / D converter 36.

  The memory controller 38 has a function of storing image data output from the external interface 40 such as a USB output connector in the memory 39 and a function of outputting image data stored in the memory 39 to the external interface 40. The memory 39 may be exemplified by a flash memory that can be attached to and detached from the camera body 1.

  The release switch (SW1) 7a is turned on by a first operation (for example, half-pressing operation or the like) of a release button (not shown), and transmits a shooting preparation start instruction signal to the MPU 100 via the switch sense circuit 105. The release switch (SW2) 7b is turned on by a second operation of the release button (for example, full-pressing operation) and transmits a shooting start instruction signal to the MPU 100 via the switch sense circuit 105. The release button corresponds to an example of the operation member of the present invention.

  The switch sense circuit 105 is connected to a main operation dial 8, a sub operation dial 20, a shooting mode setting dial 14, a focus mode switching SW 45, a main SW 43, an AF mode switching SW 44, and a photometry mode switching SW 46. The focus mode switching SW 45 is a switch for selecting a focus mode, and can select either AF (auto focus) / MF (manual focus). The AF mode switching SW 44 is a switch for selecting an AF mode, and can select one of the one-shot AF / AI servo AF / AI focus AF.

  The display drive circuit 107 drives the external display device 9 and the in-finder display device 41 in accordance with instructions from the MPU 100. The battery check circuit 108 performs a battery check for a predetermined time in accordance with an instruction from the MPU 100 and sends the check result to the MPU 100. The power supply unit 42 supplies necessary power to each element of the camera in accordance with an instruction from the MPU 100 via the power supply circuit 110. The time measuring circuit 109 measures the time and date from when the main switch 43 is turned off until it is turned on, and transmits the measurement result to the MPU 100 according to a command from the MPU 100.

  Next, the lens unit 210 will be described. The lens unit 210 includes a lens control circuit 201, and the lens control circuit 201 communicates with the MPU 100 of the camera body 1 via the mount contact portion 21. The mount contact portion 21 also has a function of transmitting a signal to the MPU 100 when the lens unit 210 is connected to the camera body 1.

  Thereby, the lens control circuit 201 communicates with the MPU 100 and drives the photographing lens 200 and the diaphragm 204 via the AF driving circuit 202 and the diaphragm driving circuit 203. In FIG. 1, for convenience of explanation, one photographic lens 200 is illustrated, but actually, the photographic lens 200 is configured by a plurality of lens groups.

  The AF drive circuit 202 is configured by, for example, a stepping motor or the like, and performs a focusing operation by changing the position of the focus lens of the photographing lens 200 in the optical axis direction under the control of the lens control circuit 201. The aperture driving circuit 203 is configured by, for example, auto iris, and is configured to obtain an optical aperture value by changing the aperture diameter of the aperture 204 under the control of the lens control circuit 201.

  2A is a schematic side sectional view of the camera when the mirror unit 500 is in the mirror down position, and FIG. 2B is a state in which the sub mirror 503 is closed with respect to the main mirror 501 when the mirror unit 500 is in the mirror down position. It is a schematic sectional side view of the camera which shows. FIG. 2C is a schematic sectional side view of the camera when the mirror unit 500 is in the mirror up position.

  As shown in FIG. 2, the main mirror 501 of the mirror unit 500 is held by the main mirror holder 502, and the sub mirror 503 is held by the sub mirror holder 504. The main mirror holder 502 is supported so as to be rotatable with respect to the mirror box 400, and the sub mirror holder 504 is supported so as to be rotatable with respect to the main mirror holder 502. The mirror unit 500 is driven by a mirror drive unit (not shown) and rotates between a mirror down position shown in FIG. 2A and a mirror up position shown in FIG.

  In the mirror-down position shown in FIG. 2A, the mirror unit 500 enters the photographing optical path, and the subject light flux that has passed through the photographing lens 200 is reflected by the main mirror 501 and partially transmitted through the main mirror 501. And reflected by the sub mirror 503. The subject light beam reflected by the main mirror 501 is guided to the pentaprism 22 via the focus plate 25 and the field mask 26 of the finder optical system 4, and the subject light beam reflected by the sub mirror 503 is guided to the focus detection unit 31.

  Therefore, in the state shown in FIG. 2A, the subject light flux that has passed through the photographing lens 200 is not guided to the image sensor 33. At this time, the amount of light of the subject image that can be confirmed by the photographer via the eyepiece 18 of the finder optical system 4 is reduced by the amount of light guided to the focus detection unit 31.

  In the state shown in FIG. 2B, the subject luminous flux that has reached the main mirror 501 is all reflected without being guided to the focus detection unit 31, and is pentaned through the focus plate 25 and the field mask 26 of the finder optical system 4. Guided to the prism 22. Therefore, the photographer can check the subject luminous flux guided to the pentaprism 22 through the eyepiece 18 as a subject image.

  In the mirror-up position shown in FIG. 2C, the mirror unit 500 is retracted from the photographing optical path, and the subject light flux that has passed through the photographing lens 200 is not guided to the finder optical system 4 and the focus detection unit 31, and thus the image sensor. The light is guided to 33 and imaged and subjected to photoelectric conversion.

  FIG. 3 is an exploded perspective view of the mirror unit 500. As shown in FIG. 3, the main mirror holder 502 is provided with rotating shafts 502 a and 502 b, and the rotating shaft 502 a is rotatably supported with respect to the mirror box 400. Further, the main mirror holder 502 is formed with an opening 502c, and the subject luminous flux transmitted through the main mirror 501 reaches the sub mirror 503 through the opening 502c.

  A hole 504 a is formed in the sub mirror holder 504, and the hole 504 a is supported so as to be rotatable with respect to the rotation shaft 502 b of the main mirror holder 502. The sub mirror holder 504 has a drive shaft 504c. When power is transmitted from a mirror drive unit (not shown) to the drive shaft 504c, the sub mirror holder 504 rotates.

  When the mirror unit 500 is in the mirror-down state, the sub mirror holder 504 rotates toward the main mirror holder 502, whereby the sub mirror holder 504 comes into contact with the main mirror holder 502 and the main mirror holder 502 is pushed up. Thereby, the mirror up operation is performed. On the other hand, when the mirror unit 500 is in the mirror up state, the main mirror holder 502 is pulled down to the sub mirror holder 504, whereby the mirror down operation is performed.

  Here, the main mirror 501 is the first mirror of the present invention, the sub mirror 503 is the second mirror of the present invention, the main mirror holder 502 is the first mirror holder of the present invention, and the sub mirror holder 504 is the present invention. This corresponds to an example of the second mirror holder. The mirror down position of the main mirror holder 502 corresponds to an example of the first position of the present invention, and the mirror up position of the main mirror holder 502 corresponds to an example of the second position of the present invention. Further, the mirror down position of the sub mirror holder 504 corresponds to an example of the third position of the present invention, and the mirror up position of the sub mirror holder 504 corresponds to an example of the fourth position of the present invention.

  Next, the operation of the mirror unit 500 will be described with reference to FIG. 4A and 4F are diagrams when the mirror unit 500 is in the mirror-down position, and FIGS. 4C and 4D are diagrams when the mirror unit 500 is in the mirror-up position. is there. FIG. 4B and FIG. 4E are diagrams when the mirror unit 500 is at an intermediate position between the mirror-down position and the mirror-up position.

  In the mirror down state of the mirror unit 500 shown in FIG. 4A, the sub mirror holder 504 is in contact with a positioning shaft 508 attached to the mirror box 400 while being biased by a spring (not shown). The main mirror holder 502 is in a mirror-down state by abutting against a positioning shaft 507 attached to the mirror box 400 while being biased by a spring (not shown).

  In this state, when power is transmitted to the drive shaft 504c of the sub mirror holder 504 by the mirror drive unit (not shown) in the direction of arrow F in the figure, the sub mirror holder 504 is directed toward the main mirror holder 502 about the rotation shaft 502b. Rotate. Then, the sub mirror holder 504 rotates to a position substantially overlapping with the main mirror holder 502, that is, an intermediate position of the mirror unit 500 shown in FIG.

  At the intermediate position of the mirror unit 500 shown in FIG. 4B, the sub mirror holder 504 waits at a position (standby position) corresponding to each photometry mode, as will be described in detail later. In this state, when power is transmitted in the direction of arrow F to the drive shaft 504c of the sub mirror holder 504 by a mirror drive unit (not shown), the sub mirror holder 504 rotates and the main mirror holder 502 is pushed up. Then, the sub mirror holder 504 rotates together with the main mirror holder 502 to the mirror up position shown in FIG.

  In the mirror up state shown in FIG. 4C, the main mirror holder 502 is pressed against the stopper portion 505 attached to the mirror box 400 by the sub mirror holder 504, and the mirror unit 500 keeps the position retracted from the photographing optical path. .

  In the mirror up state shown in FIG. 4D, the mirror down operation of the sub mirror holder 504 is started by transmitting power in the direction F in the figure to the drive shaft 504c of the sub mirror holder 504 by a mirror drive unit (not shown).

  At this time, the main mirror holder 502 is pushed down simultaneously with the sub mirror holder 504 by a spring or cam (not shown) connected to the sub mirror holder 504. Then, the main mirror holder 502 comes into contact with the positioning shaft 507, and the mirror unit 500 shown in FIG. 4 (e) is in an intermediate position. In this state, the sub mirror holder 504 stands by at a position corresponding to each photometry mode, as in FIG.

  In the state shown in FIG. 4E, the power in the direction of arrow F is transmitted to the drive shaft 504c of the sub mirror holder 504 by a mirror drive unit (not shown), so that the sub mirror holder 504 contacts the positioning shaft 508. Thereby, the sub mirror holder 504 returns to the mirror down position of the mirror unit 500 shown in FIG. The configuration of the mirror drive unit that transmits power to the drive shaft 504c of the sub mirror holder 504 is not particularly limited as long as the operation of the mirror unit 500 shown in FIG. 4 can be realized.

  Next, the standby position of the sub mirror holder 504 corresponding to each photometry mode when the mirror unit 500 is in the intermediate position will be described with reference to FIG. 5A is a diagram showing the standby position of the sub mirror holder 504 in the evaluation photometry mode, FIG. 5B is a diagram showing the standby position of the sub mirror holder 504 in the partial photometry mode, and FIG. 5C is in the spot photometry mode. It is a figure which shows the stand-by position of the sub mirror holder 504 in FIG. For convenience of explanation, in FIG. 5, the main mirror holder 502 and the sub mirror holder 504 are not shown, and the main mirror 501 and the sub mirror 503 are used for explanation.

  In the evaluation photometry mode shown in FIG. 5A, the subject luminous flux (A) that has passed through the photographing lens 200 is reflected by the main mirror 501, passes through the focus plate 25 and the field mask 26, and enters the pentaprism 22. The subject light beam (B) that has passed through the opening 502 c of the main mirror holder 502 is reflected by the sub mirror 503 and then returns to the mirror box 400 again.

  At this time, the sub mirror 503 stands by at a position opened by a predetermined angle θ1 with respect to the main mirror 501 so that the subject luminous flux (B) does not enter the evaluation photometry range X on the focus plate 25. If the subject luminous flux (B) reflected by the sub mirror 503 enters the evaluation photometric range X, the luminance partially increases and an error occurs in the photometric value, so that the photometric value needs to be corrected. . When correction of the photometric value is required, problems such as compression of ROM capacity due to the addition of a calculation table occur, and the influence on product specifications is not small.

  The partial photometry range Y in the partial photometry mode shown in FIG. 5B is narrower than the evaluation photometry range X shown in FIG. Therefore, the angle θ2 of the sub mirror 503 with respect to the main mirror 501 may be smaller than the angle θ1. Further, the spot photometry range Z in the spot photometry mode shown in FIG. 5C is narrower than the partial photometry range Y shown in FIG. Therefore, the angle θ3 of the sub mirror 503 with respect to the main mirror 501 may be smaller than the angle θ2.

  Next, the camera operation when the shutter lime lag reduction mode is selected by the shooting mode setting dial 14 will be described with reference to FIG. The processing shown in FIG. 6 is executed by the MPU 100 or the like by developing a program stored in a storage unit such as the EEPROM 100a in a RAM (not shown).

  In FIG. 6, when the shutter lime lag reduction mode is selected by the shooting mode setting dial 14 in step S601, the MPU 100 determines whether the focus mode is AF or MF. If the focus mode is AF, the MPU 100 proceeds to step S602. If the focus mode is MF, the MPU 100 ends this process.

  In step S602, when the release switch (SW1) 7a is turned on, the MPU 100 proceeds to step S603. In step S603, the MPU 100 determines which metering mode of evaluation metering / partial metering / spot metering is selected, and proceeds to step S604.

  In step S604, the MPU 100 activates the photometry circuit 24, starts photometry in the photometry mode determined in step S603 by the photometry sensor 23, and proceeds to step S605. In step S605, the MPU 100 activates the focus detection circuit 102, starts the focus detection operation by the focus detection unit 31, and proceeds to step S606.

  In step S606, the MPU 100 proceeds to step S607 when it is determined to be in focus by the focus detection unit 31, and repeats the focus detection operation by the focus detection unit 31 when determined to be out of focus.

  In step S607, the MPU 100 operates the mirror drive circuit 101, and rotates the sub mirror holder 504 to a predetermined position in the mirror up direction by a mirror drive unit (not shown) according to the photometry mode determined in step S603. The process proceeds to S608. Here, the sub mirror holder 504 rotates with respect to the main mirror holder 502 to any one of the standby positions shown in FIGS. 5 (a), 5 (b), and 5 (c).

  In step S608, the MPU 100 determines whether the subject is moving before the release switch (SW2) 7b is turned on in step S609. Here, since the mirror unit 500 is not located at the mirror down position (FIG. 4A), the focus detection unit 31 cannot determine the movement of the subject. Therefore, the subject movement is determined by a known subject recognition technique using the photometric sensor 23. Then, the MPU 100 determines that the in-focus is not affected when the amount of movement of the subject is equal to or less than the predetermined value, and proceeds to step S609, and determines that the in-focus is affected when the amount of movement of the subject exceeds the predetermined value. Then, the process proceeds to step S610.

  In step S610, the MPU 100 rotates the sub mirror holder 504 by a mirror driving unit (not shown) so that the mirror unit 500 is in the mirror down state (FIG. 4A), and returns to step S605 to perform the focus detection operation again. Do.

  In step S609, the MPU 100 determines whether or not the release switch (SW2) 7b is turned on within a predetermined time. If it is turned on, the process proceeds to step S612. If not, the process proceeds to step S611. . In step S611, the MPU 100 determines whether or not the release switch (SW1) 7a is turned off. If the release switch (SW1) 7a is not turned off, the MPU 100 returns to step S608 and waits while maintaining the intermediate position of the mirror unit 500. If it is turned off, the MPU 100 proceeds to step S617.

  In step S612, the MPU 100 determines the exposure value with the photometric value at the moment when the release switch (SW2) 7b is turned on, ends the photometry, and proceeds to step S613. By continuing photometry immediately before shooting, shooting with a more accurate exposure value becomes possible. In step S613, the MPU 100 rotates the sub mirror holder 504 in the mirror up direction by a mirror drive unit (not shown) to place the mirror unit 500 in the mirror up position (FIG. 4C), and proceeds to step S614.

  In step S614, the MPU 100 performs a series of photographing operations such as capturing of a subject image into the image sensor 33 and known image processing by the video signal processing circuit 104, and the process proceeds to step S615. In step S615, the MPU 100 rotates the sub mirror holder 504 in the mirror down direction by a mirror driving unit (not shown) to return the mirror unit 500 to the intermediate position (FIG. 4E), and proceeds to step S616.

  In step S616, the MPU 100 determines whether or not the release switch (SW1) 7a is turned off. Then, when the release switch (SW1) 7a is not turned off and the on state is maintained, the MPU 100 returns to step S608 and waits while maintaining the intermediate position of the mirror unit 500. The process proceeds to step S617.

  In step S617, the MPU 100 rotates the sub mirror holder 504 in the mirror down direction by a mirror drive unit (not shown) to return the mirror unit 500 to the mirror down position (FIG. 4 (f)), and ends a series of operations.

  As described above, in the present embodiment, when the mirror unit 500 is in the mirror down position, the sub mirror holder 504 is rotated in advance to a standby position in the vicinity of the position of the main mirror holder 502 after being focused. At this time, the standby position of the sub mirror holder 504 with respect to the main mirror holder 502 is controlled to an angle that does not affect photometry according to the photometry mode.

  As a result, it is possible to reduce the time for the sub mirror holder 504 to move to the position of the main mirror holder 502 during the mirror-up operation without performing useless correction of the photometric value, thereby further reducing the release time lag. . Further, even during the mirror down operation after the photographing is completed, it is possible to shorten the time for the sub mirror holder 504 to move from the main mirror holder 502 at the mirror down position to the mirror down position of the sub mirror holder 504.

(Second Embodiment)
Next, a camera that is a second embodiment of the imaging apparatus of the present invention will be described with reference to FIGS. Note that portions that overlap or correspond to the first embodiment will be described with reference to the drawings and symbols.

  FIG. 7 is a flowchart for explaining the camera operation when the shutter lime lag reduction mode is selected by the shooting mode setting dial 14. FIG. 8 is a flowchart for explaining the interval metering process in step S707 of FIG. The processing shown in FIGS. 7 and 8 is executed by the MPU 100 or the like by developing a program stored in a storage unit such as the EEPROM 100a in a RAM (not shown). Note that steps S701 to S706 and steps S708 to S713 in FIG. 7 are the same as the processes in steps S601 to S606 and steps S612 to S617 in FIG. 6, respectively, and therefore only step S707 in FIG. Explanation will be made with reference to FIG.

  In FIG. 7, when the MPU 100 determines that the focus detection unit 31 is in focus in step S706, the process proceeds to step S707. In step S707, the MPU 100 starts interval photometry processing in which photometry is repeatedly turned on / off at regular intervals (for example, at intervals of 1 second) by the photometry circuit 24. Hereinafter, the interval metering process will be described in detail with reference to FIG.

  In FIG. 8, in step S801, the MPU 100 starts photometry by the photometry sensor 23 using the photometry circuit 24, and proceeds to step S802. In step S802, the MPU 100 operates the mirror drive circuit 101, and rotates the sub mirror holder 504 to a predetermined position in the mirror up direction by a mirror drive unit (not shown) according to the photometry mode determined in step S703. The process proceeds to S803. Here, the sub mirror holder 504 rotates with respect to the main mirror holder 502 to one of the positions (standby position) in FIGS. 5A, 5B, and 5C.

  In step S803, the MPU 100 determines whether or not the release switch (SW2) 7b is turned on. If it is turned on, the MPU 100 ends the process and proceeds to step S708 in FIG. Proceed to In step S804, the MPU 100 determines whether a predetermined time (for example, 1 second) has elapsed from the time measurement result by the time measurement circuit 109 after the process in step S802. If the predetermined time has not elapsed, the MPU 100 returns to step S802, and if the predetermined time has elapsed, the MPU 100 proceeds to step S805.

  In step S805, the MPU 100 rotates the sub mirror holder 504 in the mirror up direction by a mirror driving unit (not shown) to contact the main mirror holder 502, and proceeds to step S806. Here, since the sub mirror holder 504 overlaps the main mirror holder 502 without a gap, the rotation time of the sub mirror holder 504 corresponding to the gap during the mirror up operation is reduced. Thereby, it is possible to shorten the time lag until the photographing operation in step S710 of FIG.

  In step S806, the MPU 100 once ends photometry with the photometry sensor 23 by the photometry circuit 24, and proceeds to step S807. Here, since the sub mirror 503 is closed with respect to the main mirror 501 in step S805, once the photometry is finished, the reflected light from the sub mirror 503 enters the photometric sensor 23 and an error occurs in the photometric value. Avoid it.

  In step S807, the MPU 100 determines whether or not the release switch (SW2) 7b is turned on. If the release switch (SW2) 7b is turned on, the MPU 100 ends the process and proceeds to step S708 in FIG. The process proceeds to S808. In step S808, the MPU 100 determines whether a predetermined time (for example, 1 second) has elapsed from the time measurement result by the time measurement circuit 109 after the process in step S805. If the predetermined time has not elapsed, the MPU 100 returns to step S805. If the predetermined time has elapsed, the MPU 100 returns to step S801 and starts photometry again.

  As described above, in the present embodiment, interval metering is employed, and the gap between the sub mirror holder 504 and the main mirror holder 502 at the standby position is eliminated while metering is off, so that the rotation of the sub mirror holder 504 corresponding to the gap is eliminated. Dynamic time is reduced. Thereby, it is possible to shorten the time lag until the photographing operation. Other configurations and operational effects are the same as those in the first embodiment.

(Third embodiment)
Next, a camera which is a third embodiment of the imaging apparatus of the present invention will be described with reference to FIG. Note that portions that overlap or correspond to the first embodiment will be described with reference to the drawings and symbols.

  FIG. 9 is a flowchart for explaining the camera operation when the shutter lime lag reduction mode is selected by the shooting mode setting dial 14. The processing shown in FIG. 9 is executed by the MPU 100 or the like by developing a program stored in a storage unit such as the EEPROM 100a in a RAM (not shown). Note that steps S901 to S906 in FIG. 9 are the same as the processes in steps S601 to S606 in FIG.

  In FIG. 9, in step S907, the MPU 100 determines whether or not the release switch (SW2) 7b is turned on within a predetermined time. If it is turned on, the process proceeds to step S908. The process proceeds to step S909.

  In step S909, the MPU 100 determines whether or not the release switch (SW1) 7a is turned off. If the release switch (SW1) 7a is not turned off, the MPU 100 returns to step S907 to determine whether the release switch (SW2) 7b is on or off, and if the release switch (SW1) 7a is turned off. Ends the process.

  In step S908, the MPU 100 receives the ON signal of the release switch (SW2) 7b, starts driving the sub mirror holder 504 in the mirror up direction by a mirror driving unit (not shown), and proceeds to step S910.

  In step S910, the MPU 100 determines that the sub-mirror holder 504 is in a predetermined position according to the photometry mode determined in step S903 (a standby position in any one of FIGS. 5A, 5B, and 5C). It is determined whether or not it has been rotated.

  Here, the rotation position of the sub mirror holder 504 is determined by using known means such as detecting the position by detecting a pulse using a stepping motor as a mirror drive motor, or detecting the position by a phase plate. Use. If the MPU 100 determines that the sub mirror holder 504 has rotated to a predetermined position, the MPU 100 proceeds to step S911. Otherwise, the MPU 100 waits until the sub mirror holder 504 rotates to a predetermined position.

  In step S911, the MPU 100 determines the exposure value based on the photometric value detected at the timing when it is determined in step S910 that the sub mirror holder 504 has been rotated to the predetermined position, ends the photometry, and proceeds to step S912.

  In step S912, the MPU 100 rotates the sub mirror holder 504 in the mirror up direction by a mirror drive unit (not shown) to place the mirror unit 500 in the mirror up position (FIG. 4C), and proceeds to step S913.

  In step S913, the MPU 100 performs a series of photographing operations such as capturing of a subject image into the image sensor 33 and known image processing by the video signal processing circuit 104, and the process proceeds to step S914. In step S914, the MPU 100 returns the mirror unit 500 to the mirror down position (FIG. 4 (f)) by rotating the sub mirror holder 504 in the mirror down direction by a mirror drive unit (not shown), and proceeds to step S915.

  In step S915, the MPU 100 determines whether or not the release switch (SW1) 7a is turned off. If the release switch (SW1) 7a is not turned off, the MPU 100 returns to step S905 to wait for the focus determination, and if it is turned off, the MPU 100 ends the process.

  As described above, in the present embodiment, after the release switch (SW2) 7b is turned on, the sub-mirror holder 504 is driven to the standby position and photometry is performed during a series of operations until the end of shooting, and exposure determination is performed immediately before shooting. It is decided by. For this reason, it is possible to shoot with accurate exposure while reducing the release time lag. Other configurations and operational effects are the same as those in the first embodiment.

  In addition, this invention is not limited to what was illustrated by said each embodiment, In the range which does not deviate from the summary of this invention, it can change suitably.

4 Viewfinder optical system 7a Release switch (SW1)
7b Release switch (SW2)
23 photometric sensor 31 focus detection unit 33 image sensor 100 MPU
500 Mirror unit 501 Main mirror 502 Main mirror holder 503 Sub mirror 504 Sub mirror holder

Claims (6)

A first mirror holder capable of moving between a first position holding the first mirror in the imaging optical path and a second position retracting from the imaging optical path; and the first mirror holder A second, which is pivotably attached, is capable of moving between a third position that holds the second mirror and is located in the photographing optical path and a fourth position that is retracted from the photographing optical path. A mirror holder, and at the time of finder observation, the first mirror holder is located at the first position, and the second mirror holder is located at the third position. The reflected subject light beam is reflected by the first mirror and guided to the finder optical system, and the subject light beam transmitted through the first mirror is reflected by the second mirror and guided to the focus detection means. The first mirror holder is the second mirror holder. While it is moving to a position, and said second mirror holder is moved to the fourth position, the mirror unit for guiding the subject light flux passing through the photographing optical system to the imaging device,
Driving the second mirror holder between the third position and the fourth position, and moving the second mirror holder from the third position to the fourth position; Driving means for moving the first mirror holder from the first position to the second position;
A photometric means having a plurality of photometric modes;
An instruction means for instructing a focus detection operation by the focus detection means by a first operation of the operation member, and for instructing an image by the image sensor by a second operation of the operation member;
After completion of the focus detection operation by an instruction based on the first operation of the instruction means, the driving means causes the first position at the third position toward the first mirror holder at the first position. The second mirror holder is rotated, and the second mirror holder is opened by a predetermined angle with respect to the first mirror holder in accordance with the photometric mode selected by the user among the photometric modes. Wait in position,
Based on an instruction for imaging by the imaging element based on the second operation of the instruction unit after the focus detection operation is completed, the driving unit moves the second mirror holder from the standby position to the fourth position. An imaging apparatus comprising: control means for rotating the first mirror holder to move the first mirror holder from the first position to the second position. The control means rotates the second mirror holder from the fourth position to the standby position by the driving means after the imaging by the imaging element is completed, and moves the first mirror holder to the second position. Moving from the position to the first position,
The second mirror holder is rotated from the standby position to the third position by the driving means when there is no instruction for the focus detection operation based on the first operation by the instruction means. The imaging device according to claim 1.   After the focus detection operation is finished, the control means has no instruction for imaging by the imaging device based on the second operation of the instruction means for a predetermined time, and the focus based on the first operation of the instruction means When there is no instruction for the detection operation, the driving means rotates the second mirror holder at the standby position toward the third position without rotating toward the fourth position. The imaging apparatus according to claim 1 or 2, wherein   In the state where the second mirror holder in the third position rotates toward the first mirror holder in the first position and is positioned in the standby position, When the photometric means determines that the subject has moved, the driving means rotates the second mirror holder from the standby position toward the third position, and the focus detection means again detects the focus. The imaging apparatus according to claim 1, wherein the imaging apparatus performs an operation. The photometric means repeats photometry at regular intervals,
When the photometry is being performed by the photometry means, the control means places the second mirror holder at the first position according to the photometry mode at the standby position of the second mirror holder. When the photometric means does not perform photometry, the second mirror holder is placed on the first mirror holder at the first position when the photometric means does not perform photometry. The drive means is controlled so that the second mirror holder in the third position is rotated toward the first mirror holder and waits until it abuts. 5. The imaging device according to any one of 4. A first mirror holder capable of moving between a first position holding the first mirror in the imaging optical path and a second position retracting from the imaging optical path; and the first mirror holder A second, which is pivotably attached, is capable of moving between a third position that holds the second mirror and is located in the photographing optical path and a fourth position that is retracted from the photographing optical path. A mirror holder, and at the time of finder observation, the first mirror holder is located at the first position, and the second mirror holder is located at the third position. The reflected subject light beam is reflected by the first mirror and guided to the finder optical system, and the subject light beam transmitted through the first mirror is reflected by the second mirror and guided to the focus detection means. The first mirror holder is the second mirror holder. While it is moving to a position, and said second mirror holder is moved to the fourth position, the mirror unit for guiding the subject light flux passing through the photographing optical system to the imaging device,
Driving the second mirror holder between the third position and the fourth position, and moving the second mirror holder from the third position to the fourth position; Driving means for moving the first mirror holder from the first position to the second position;
A photometric means having a plurality of photometric modes;
An instruction means for instructing a focus detection operation by the focus detection means by a first operation of the operation member, and for instructing an image by the image sensor by a second operation of the operation member;
After completion of the focus detection operation by the instruction based on the first operation of the instruction means, when the instruction means instructs the imaging device to perform imaging based on the second operation, the driving means causes the first The second mirror holder in the third position is rotated toward the first mirror holder in the first position, and the second mirror holder is moved by the user in the plurality of photometric modes. Control that performs photometry by the photometry means until reaching a standby position that is opened by a predetermined angle with respect to the first mirror holder in accordance with the selected photometry mode, and performs imaging by the image sensor after the photometry is completed. And an imaging device.

Images