JP2008294590A - Imaging device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging device capable of suitably detecting a defective pixel of an imaging element receiving luminous flux for observation. <P>SOLUTION: The imaging device 1 includes a finder optical system guiding to a finder window 10 the luminous flux for observation which is luminous flux from a photography optical system and reflected by a main reflecting surface 61, the imaging element 7 which receives the luminous flux for observation and generates an image signal, and a control means of moving the main reflecting surface 61 to a mirror-up position PS1 to shield a predetermined space SU including the imaging element 7 from the light and acquiring an exposure image of the imaging element 7 in the light shield state to detect a defective pixel of the imaging element 7. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an imaging apparatus such as a digital camera.

  In a single-lens reflex type camera (also referred to as a single-lens reflex camera), a live view function (a function for sequentially displaying time-series images related to a subject on a liquid crystal display unit or the like, in other words, a subject image is displayed in a liquid crystal display in a moving image mode There is a technology that is equipped with a function to display in a section or the like.

  For example, in the camera of Patent Document 1, an image sensor for live view that is different from an image sensor for image capturing (for still image recording) is provided in the vicinity of the finder optical system. In addition, a movable reflecting mirror capable of moving back and forth with respect to the optical path is provided in the finder optical path near the eyepiece. Then, when the reflecting mirror moves back and forth with respect to the finder optical path, the situation where the observation light flux from the subject goes to the eyepiece and the situation where the observation light flux from the subject reaches the live view image sensor is selected. Can be switched automatically. In the camera, a live view function is realized using a light image guided to an image sensor for live view.

Japanese Patent Laid-Open No. 2001-133848

  By the way, in the same way as an image sensor for recording a still image, an acquired defect pixel due to the influence of cosmic rays or the like occurs in an image sensor (such as the above-described live view image sensor) that receives an observation beam. Can do. Such defective pixels are undesirable because they cause degradation of live view images and the like.

  However, sufficient measures have not yet been taken for countermeasures against defective pixels in image sensors that receive observation light beams.

  Accordingly, an object of the present invention is to provide an imaging apparatus capable of appropriately detecting defective pixels of an imaging element that receives an observation light beam.

  The present invention provides an imaging apparatus, a finder optical system that guides an observation light beam, which is a light beam from a photographing optical system and reflected by a main reflection surface, to a finder window, and receives the observation light beam. A first imaging element that generates an image signal and moving the main reflection surface to a mirror-up position to place a predetermined space including the first imaging element in a light-shielding state, and the first imaging in the light-shielding state Control means for acquiring an exposure image of the element and detecting defective pixels of the first image sensor.

  According to the present invention, the main reflection surface is moved to the mirror-up position so that the predetermined space including the first image sensor is shielded, and an exposure image of the first image sensor in the shield state is acquired and the first image sensor is acquired. Since defective pixels of one image sensor are detected, it is possible to appropriately detect defective pixels of the first image sensor.

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

<1. First Embodiment>
<1-1. Outline of configuration>
1 and 2 are diagrams showing an external configuration of the imaging apparatus 1 (1A) according to the first embodiment of the present invention. Here, FIG. 1 is a front external view of the image pickup apparatus 1, and FIG. 2 is a rear external view of the image pickup apparatus 1. This imaging device 1 is configured as a lens interchangeable single-lens reflex digital camera.

  As shown in FIG. 1, the imaging device 1 includes a camera body (camera body) 2. An interchangeable photographic lens unit (interchangeable lens) 3 can be attached to and detached from the camera body 2.

  The photographic lens unit 3 mainly includes a lens barrel 36, a lens group 37 (see FIG. 3) provided in the lens barrel 36, a diaphragm, and the like. The lens group 37 (shooting optical system) includes a focus lens that changes the focal position by moving in the optical axis direction.

  The camera body 2 includes an annular mount Mt to which the photographing lens unit 3 is attached at the front center, and an attach / detach button 89 for attaching / detaching the photographing lens unit 3 near the annular mount Mt. Yes.

  Further, the camera body 2 is provided with a mode setting dial 82 in the upper left part of the front surface and a control value setting dial 86 in the upper right part of the front surface. By operating the mode setting dial 82, various camera modes (such as various shooting modes (portrait shooting mode, landscape shooting mode, full-auto shooting mode, etc.), playback mode for playing back captured images, (Including a communication mode in which data communication is performed) is performed (switching operation). Further, by operating the control value setting dial 86, it is possible to set control values in various shooting modes.

  Further, the camera body 2 includes a grip portion 14 for a photographer to hold at the left end of the front. A release button 11 for instructing the start of exposure is provided on the upper surface of the grip portion 14. A battery storage chamber and a card storage chamber are provided inside the grip portion 14. For example, four AA batteries are housed in the battery compartment as a power source for the camera, and a memory card 90 (see FIG. 3) for recording image data of a photographed image can be attached to and detached from the card compartment. It is designed to be stored in.

  The release button 11 is a two-stage detection button that can detect two states, a half-pressed state (S1 state) and a fully-pressed state (S2 state). When the release button 11 is half-pressed to enter the S1 state, a preparation operation (for example, an AF control operation and an AE control operation) for acquiring a recording still image (main captured image) related to the subject is performed. When the release button 11 is further pushed into the S2 state, an exposure operation related to a subject image (light image of the subject is performed using the imaging device 5 (described later) using the imaging element 5 (described later), and the exposure operation is performed. A series of operations for applying predetermined image processing to the obtained image signal is performed.

  In FIG. 2, a finder window (eyepiece window) 10 is provided at the upper center of the back surface of the camera body 2. The photographer can determine the composition by viewing the viewfinder window 10 and visually recognizing the light image of the subject guided from the photographing lens unit 3. That is, it is possible to determine the composition using an optical finder.

  In the imaging apparatus 1 according to this embodiment, the composition can be determined using a live view image displayed on the rear monitor 12 (described later). Further, the switching operation between the composition determination operation by the optical finder and the composition determination operation by the live view display is realized by the operator rotating the switching dial 87. This switching operation and the like will be described in detail later.

  In FIG. 2, a rear monitor 12 is provided in the approximate center of the rear surface of the camera body 2. The rear monitor 12 is configured as a color liquid crystal display (LCD), for example. The rear monitor 12 can display a menu screen for setting shooting conditions and the like, and can reproduce and display a captured image recorded in the memory card 90 in the reproduction mode. In addition, when the operator selects composition determination based on live view display instead of composition determination based on the optical finder, a plurality of time-series images (that is, moving images) acquired by the image sensor 7 (described later) are displayed on the rear monitor 12. Image) is displayed as a live view image.

  A main switch 81 is provided at the upper left of the rear monitor 12. The main switch 81 is a two-point slide switch. When the contact is set to the left “OFF” position, the power is turned off. When the contact is set to the right “ON” position, the power is turned on.

  A direction selection key 84 is provided on the right side of the rear monitor 12. This direction selection key 84 has a circular operation button, and it is possible to detect a pressing operation in four directions of up, down, left and right, and a pressing operation in four directions of upper right, upper left, lower right and lower left on this operation button. It has become. In addition, the direction selection key 84 is configured to detect a pressing operation of a push button at the center, in addition to the pressing operations in the eight directions.

  A setting button group 83 including a plurality of buttons for setting a menu screen, deleting an image, and the like is provided on the left side of the rear monitor 12.

<1-2. Functional block>
Next, an overview of functions of the imaging apparatus 1 will be described with reference to FIG. FIG. 3 is a block diagram illustrating a functional configuration of the imaging apparatus 1.

  As shown in FIG. 3, the imaging apparatus 1 includes an operation unit 80, an overall control unit 101, a focus control unit 121, a mirror control unit 122, a shutter control unit 123, a timing control circuit 124, a digital signal processing circuit 50, and the like. .

  The operation unit 80 includes various buttons and switches including the release button 11 (see FIG. 1). In response to a user input operation on the operation unit 80, the overall control unit 101 implements various operations.

  The overall control unit 101 is configured as a microcomputer and mainly includes a CPU, a memory, a ROM, and the like. The overall control unit 101 implements various functions by reading a program stored in the ROM and executing the program by the CPU.

  For example, the overall control unit 101 realizes a defective pixel detection operation or the like of the image sensor 7 described later. The overall control unit 101 performs a focus control operation for controlling the position of the focus lens in cooperation with the AF module 20, the focus control unit 121, and the like. The overall control unit 101 implements an AF operation using the focus control unit 121 according to the focus state of the subject detected by the AF module 20. The AF module 20 can detect the in-focus state of the subject by using the light that has entered through the mirror mechanism 6 by a focus state detection method such as a phase difference method.

  The focus control unit 121 moves a focus lens included in the lens group 37 of the photographing lens unit 3 by generating a control signal based on a signal input from the overall control unit 101 and driving the motor M1. The position of the focus lens is detected by the lens position detection unit 39 of the photographing lens unit 3, and data indicating the position of the focus lens is sent to the overall control unit 101. As described above, the focus control unit 121, the overall control unit 101, and the like control the movement of the focus lens in the optical axis direction.

  The mirror control unit 122 controls state switching between a state in which the mirror mechanism 6 is retracted from the optical path (mirror up state) and a state in which the mirror mechanism 6 blocks the optical path (mirror down state). The mirror control unit 122 switches between the mirror up state and the mirror down state by generating a control signal based on the signal input from the overall control unit 101 and driving the motor M2.

  The shutter control unit 123 controls the opening and closing of the shutter 4 by generating a control signal based on the signal input from the overall control unit 101 and driving the motor M3.

  The timing control circuit 124 performs timing control for the image sensor 5 and the like.

  An imaging device (here, a CCD sensor (also simply referred to as a CCD)) 5 converts an optical image of a subject into an electrical signal by a photoelectric conversion action, and generates an image signal (recording image signal) related to the actual captured image. To do. The image sensor 5 is also expressed as an image sensor for acquiring a recorded image.

  In response to the drive control signals (accumulation start signal and accumulation end signal) input from the timing control circuit 124, the image sensor 5 performs exposure (charge accumulation by photoelectric conversion) of the subject image formed on the light receiving surface. Then, an image signal related to the subject image is generated. Further, the image sensor 5 outputs the image signal to the signal processing unit 51 in response to the read control signal input from the timing control circuit 124. The timing signal (synchronization signal) from the timing control circuit 124 is also input to the signal processing unit 51 and the A / D (analog / digital) conversion circuit 52.

  The image signal acquired by the image sensor 5 is subjected to predetermined analog signal processing in the signal processing unit 51, and the image signal after the analog signal processing is converted into digital image data (image data) by the A / D conversion circuit 52. Is done. This image data is input to the digital signal processing circuit 50.

  The digital signal processing circuit 50 performs digital signal processing on the image data input from the A / D conversion circuit 52 to generate image data related to the captured image. The digital signal processing circuit 50 includes a black level correction circuit 53, a white balance (WB) circuit 54, a γ correction circuit 55, and an image memory 56.

  The black level correction circuit 53 corrects the black level of each pixel data constituting the image data output from the A / D conversion circuit 52 to a reference black level. The WB circuit 54 performs white balance adjustment of the image. The γ correction circuit 55 performs gradation conversion of the captured image. The image memory 56 is a high-speed accessible image memory for temporarily storing generated image data, and has a capacity capable of storing image data for a plurality of frames.

  At the time of actual photographing, the image data temporarily stored in the image memory 56 is appropriately subjected to image processing (such as compression processing) in the overall control unit 101 and then stored in the memory card 90 via the card I / F 132.

  Further, the image data temporarily stored in the image memory 56 is appropriately transferred to the VRAM 131 by the overall control unit 101, and an image based on the image data is displayed on the rear monitor 12. Thereby, confirmation display (after view) for confirming the captured image, reproduction display for reproducing the captured image, and the like are realized.

  The imaging apparatus 1 further includes an imaging element 7 (see also FIG. 4) that is different from the imaging element 5. The image sensor 7 serves as a so-called live view image acquisition (moving image acquisition) image sensor. The image sensor 7 also has the same configuration as the image sensor 5. However, the image sensor 7 only needs to have a resolution for generating an image signal (moving image) for live view, and is usually configured with a smaller number of pixels than the image sensor 5.

  The same signal processing as that of the image signal acquired by the image sensor 5 is performed on the image signal acquired by the image sensor 7. That is, the image signal acquired by the image sensor 7 is subjected to predetermined processing by the signal processing unit 51, converted into digital data by the A / D conversion circuit 52, and then subjected to predetermined image processing by the digital signal processing circuit 50. And stored in the image memory 56.

  The time series image data acquired by the image sensor 7 and stored in the image memory 56 is sequentially transferred to the VRAM 131 as appropriate by the overall control unit 101, and an image based on the time series image data is displayed on the rear monitor 12. Is done. As a result, display of a moving image mode (live view display) for composition determination is realized.

  In particular, when a defective pixel detection operation of the image sensor 7 is performed together with a photographing operation by the image sensor 5 as will be described later, image processing related to the image sensor 5 and image processing related to the image sensor 7 are performed in order to increase the processing speed. Are preferably processed in parallel. Therefore, here, it is assumed that the timing control circuit 124, the signal processing unit 51, the A / D conversion circuit 52, the digital signal processing circuit 50, and the like each have two systems of processing circuits. Assume that image processing is performed in parallel. However, the present invention is not limited to this, and only one system is provided for the timing control circuit 124, the signal processing unit 51, the A / D conversion circuit 52, the digital signal processing circuit 50, and the like. You may make it perform the image process regarding the image pick-up element 7 sequentially in this order or reverse order.

  Furthermore, the imaging apparatus 1 has a communication I / F 133 and can perform data communication with a device (for example, a personal computer) to which the interface 133 is connected.

  The imaging device 1 also includes a flash 41, a flash control circuit 42, and an AF auxiliary light emitting unit 43. The flash 41 is a light source used when the luminance of the subject is insufficient. Whether or not the flash is turned on and the lighting time are controlled by the flash control circuit 42, the overall control unit 101, and the like. The AF auxiliary light emitting unit 43 is an auxiliary light source for AF. The presence or absence of lighting of the AF auxiliary light emitting unit 43 and the lighting time are controlled by the overall control unit 101 and the like.

<1-3. Shooting action>
<Overview>
Next, a photographing operation including a composition determining operation in the imaging apparatus 1 will be described. As described above, in the imaging apparatus 1, composition determination (framing) can be performed using an optical viewfinder (also referred to as an optical viewfinder (OVF)) configured by a viewfinder optical system or the like. The composition can also be determined using a live view image displayed on the rear monitor 12 (described later). The finder function realized using the image sensor 7 and the rear monitor 12 is also referred to as an electronic view finder (EVF) because it visualizes a light image of a subject after converting it into electronic data.

  As will be described later, the operator operates the switching dial 87 to determine the composition using the optical viewfinder (OVF) or whether the operator determines the composition using the electronic viewfinder (EVF). You can choose.

  4 and 5 are cross-sectional views of the imaging device 1. FIG. 4 shows a composition determination operation using the OVF, and FIG. 5 shows a composition determination operation using the EVF. FIG. 6 is a cross-sectional view showing a state during an exposure operation (specifically, during OVF).

  As shown in FIG. 4 and the like, a mirror mechanism 6 is provided on the optical path (imaging optical path) from the imaging lens unit 3 to the image sensor 5. The mirror mechanism 6 has a main mirror 61 (main reflection surface) that reflects light from the photographing optical system upward. For example, a part or all of the main mirror 61 is configured as a half mirror, and transmits a part of light from the photographing optical system. The mirror mechanism 6 also includes a sub mirror 62 (sub reflective surface) that reflects light transmitted through the main mirror 61 downward. The light reflected downward by the sub mirror 62 is guided to the AF module 20 and is incident thereon, and is used for the phase difference type AF operation.

  Until the release button 11 is fully pressed S2 in the photographing mode, in other words, when determining the composition, the mirror mechanism 6 is arranged so as to be in the mirror-down state (see FIGS. 4 and 5). At this time, the subject image from the photographic lens unit 3 is reflected upward by the main mirror 61 and enters the pentamirror 65 as an observation light beam. The pentamirror 65 has a plurality of mirrors (reflection surfaces) and has a function of adjusting the orientation of the subject image. Further, the path of the observation light beam after entering the pentamirror 65 differs depending on which of the above-described two methods (that is, the OVF method and the EVF method) is used for composition determination. This will be described later. The operator can determine the composition according to the selected desired method.

  On the other hand, when the release button 11 is fully pressed S2, the mirror mechanism 6 is driven so as to be in the mirror up state, and an exposure operation is started (see FIG. 6). The basic operation (that is, the operation at the time of exposure) at the time of acquiring a recording still image (also referred to as an actual captured image) relating to the subject is common to the composition determination by both of the above methods (that is, the OVF method and the EVF method). is there.

  Specifically, as shown in FIG. 6, at the time of exposure, the mirror mechanism 6 is retracted from the photographing optical path. Specifically, the main mirror 61 and the sub mirror 62 are retracted upward so as not to block the light (subject image) from the photographic optical system, and the light from the photographic lens unit 3 is synchronized with the opening timing of the shutter 4. Reach 5 The imaging element 5 generates an image signal of the subject based on the received light flux by photoelectric conversion. As described above, the light from the subject is guided to the image sensor 5 through the photographing lens unit 3, thereby obtaining a photographed image (photographed image data) relating to the subject.

  In this embodiment, when the composition is determined by the EVF method, a defective pixel detection operation or the like in the image sensor 7 is additionally performed in the recording still image (main captured image) acquisition operation described above. Executed. The defective pixel detection operation and the like will be described in detail later.

<Composition determination operation by optical finder (framing operation)>
Next, each of the above-described two operations when determining the composition will be described.

  First, the composition determination operation of the OVF method will be described.

  As shown in FIG. 4, when the main mirror 61 and the sub mirror 62 of the mirror mechanism 6 are arranged on the optical path of the subject image from the photographing lens unit 3, the subject image is the main mirror 61, the pentamirror 65, and the eyepiece 67. To the viewfinder window 10. As described above, the finder optical system including the main mirror 61, the pentamirror 65, and the eyepiece lens 67 transmits the observation light beam, which is a light beam from the photographing optical system and reflected by the main mirror 61, to the finder window 10. It is possible to lead to.

  Specifically, the light from the photographic lens unit 3 is reflected by the main mirror 61, changes its path upward, forms an image on the focusing screen 63, and passes through the focusing screen 63. Thereafter, the light passing through the focusing screen 63 is further changed in its path by the pentamirror 65, and then travels through the eyepiece lens 67 to the finder window 10 (see the optical path PA in FIG. 4). In this way, the subject image that has passed through the finder window 10 reaches the eye of the photographer (observer) and is visually recognized. That is, the photographer can confirm the subject image by looking through the finder window 10.

  Here, the pentamirror 65 includes two mirrors (dach mirrors) 65a and 65b (see also FIG. 7) formed in a triangular roof shape, and a surface 65c fixed to the roof mirrors (dach surfaces) 65a and 65b. And another mirror (reflection surface) 65e. Further, the two mirrors 65a and 65b having a triangular roof shape are formed as an integral part 65d by plastic molding. The light that has been reflected by the main mirror 61 and has changed its path upward is reflected by the roof mirrors 65a and 65b, is reversed left and right, and is further reflected by the mirror 65e so that it is also vertically reversed to the photographer's eyes. To reach. In this way, the left and right and up and down light images in the photographic lens unit 3 are further reversed by the pentamirror 65 in the left and right and up and down directions. Thus, the photographer can observe the subject image in the optical viewfinder in the same state as the actual subject in the vertical and horizontal directions.

  Here, an optical unit U1 which is a part of the finder optical system is provided in the upper space SU inside the imaging apparatus 1. The optical unit U1 includes an eyepiece 67 and a finder window 10, and further includes an eyepiece shutter 16 that can be opened and closed by a driving unit (not shown). During the OVF system composition determination operation, the eyepiece shutter 16 is opened, and the subject image from the pentamirror 65 passes through the finder window 10.

  Further, the light that has passed through the main mirror 61 is reflected by the sub mirror 62, changes its path downward, and enters the AF module 20. The AF module 20, the focus control unit 121, and the like implement an AF operation using light that has entered through the main mirror 61 and the sub mirror 62.

<Composition determination operation using electronic viewfinder (framing operation)>
Next, the composition determination operation by the EVF method will be described.

  Also in this case, as shown in FIG. 5, the main mirror 61 and the sub mirror 62 of the mirror mechanism 6 are arranged on the optical path of the subject image from the photographing lens unit 3. Then, the light from the photographic lens unit 3 is reflected by the main mirror 61, changes the course upward, forms an image on the focusing screen 63, and passes through the focusing screen 63.

  However, in this EVF system composition determination operation, the path of light that has passed through the focusing screen 63 is further changed by the pentamirror 65, and then the path is further changed by the beam splitter 71 to form the imaging lens 69 (concatenation). The image is re-imaged on the imaging surface of the image sensor 7 through the image optical system (see the optical path PB in FIG. 5). The light reflected by the main mirror 61 and whose path has been changed upward is reflected by the roof mirrors 65a and 65b to be reversed left and right, and further reflected by the mirror 65e so that it is also vertically reversed and further imaged. The lens 69 is inverted vertically and horizontally and reaches the image sensor 7.

  More specifically, as can be seen from comparison with FIG. 4, the angle of the mirror 65 e (installation angle with respect to the camera body 2) is changed in FIG. 5. Specifically, the mirror 65e is rotated from the state of FIG. 4 by a predetermined angle α around the axis AX1 on the lower end side in the direction of the arrow AR1. As will be described later, the mirror 65e rotates in accordance with the operation of the photographer.

  Then, by changing the angle of the mirror 65e, the reflection angle of the light (observation light beam) reflected by the mirror 65e is changed, and the traveling path of the reflected light by the mirror 65e is changed. Specifically, compared with the state of FIG. 4, the incident angle θ1 to the mirror 65e is relatively small, and the reflection angle θ2 is also relatively small. As a result, the reflected light of the mirror 65e changes its path upward from the optical path toward the eyepiece lens 67 to the optical path near the roof mirrors 65a and 65b, toward the beam splitter 71, and further changes its path by the beam splitter 71. Then, it passes through the imaging lens 69 and reaches the image sensor 7. The beam splitter 71, the imaging lens 69, and the image sensor 7 are disposed above the eyepiece lens 67, and are positioned so as not to block the light beam traveling from the mirror 65e to the eyepiece lens 67 during OVF. Is arranged.

  Further, the path of the light beam reflected by the mirror 65e is changed by an angle β (= 2 × α) that is twice as large as the change angle α of the mirror 65e. In other words, in order to change the traveling angle of the reflected light path by the angle β, the rotation angle of the mirror 65e may be an angle α that is half the angle β. That is, it is possible to change the path of the reflected light of the mirror 65e relatively large with a relatively small rotation angle of the mirror 65e. Further, since the mirror 65e and the image sensor 7 are optically separated from each other, the two reflected lights by the mirror 65e are arranged away from each other only by changing the rotation angle of the mirror 65e small. It is possible to reliably lead to the eyepiece 67 and the image sensor 7. That is, by changing the rotation angle of the mirror 65e to be small, the light beam reflected by the mirror 65e can be selectively advanced to two optical paths. Therefore, an increase in space due to the rotation of the mirror 65e is minimized.

  The image sensor 7 generates a live view image based on the subject image reflected by the mirror 65e, passing through the imaging lens 69, and reaching the image sensor 7. Specifically, a plurality of images are sequentially generated at a minute time interval (for example, 1/60 seconds). The acquired time-series images are sequentially displayed on the rear monitor 12. Thus, the photographer can visually recognize the moving image (live view image) displayed on the rear monitor 12 and determine the composition using the moving image.

  During the EVF composition determination operation, the eyepiece shutter 16 is opened so that light from the finder window 10 does not enter the upper space SU.

  Also in this case, the AF operation is realized using light incident on the AF module 20 via the main mirror 61 and the sub mirror 62, as in the case of composition determination by the OVF (see FIG. 4).

  As described above, the path (specifically, the main path) of the observation light beam after being reflected by the mirror 65e is the optical path PA (from the mirror 65e to the eyepiece lens 67 and the viewfinder window 10 by changing the reflection angle of the mirror 65e. 4) and the optical path PB (FIG. 5) from the mirror 65e toward the imaging lens 69 and the image sensor 7. In other words, the path of the observation light beam is reflected by the mirror 65e by the change in the reflection angle of the mirror 65e, and is reflected by the mirror 65e and reflected by the mirror 65e toward the image sensor 7. It is switched between the second optical path PB.

  According to the imaging apparatus 1, live view display can be performed without providing a movable reflection mirror that can advance and retreat with respect to the optical path of the subject image in the optical path in the vicinity of the eyepiece 67 of the finder optical system as in the conventional technique. Can be realized. In other words, according to the imaging device 1, live view display can be realized with a compact configuration.

  Moreover, in the imaging device 1, while the reflection angle of a certain reflective surface (mirror 65e) is changed among the plurality of mirrors 65a, 65b, and 65e constituting the pentamirror 65, the other reflective surface (the roof mirror 65a) is changed. , 65b) are fixed. That is, the path of the observation light beam is changed by driving only one reflection surface 65e among the plurality of reflection surfaces, so that the drive portion can be reduced and the configuration can be made compact.

  In the imaging apparatus 1, the reflection angle of the mirror 65e, which is a reflection surface other than the roof mirrors 65a and 65b among the plurality of reflection surfaces included in the pentamirror 65 of the finder optical system, is changed, and the path of the observation light beam is changed. Therefore, the path of the observation light beam can be easily changed as compared with the case where the roof mirrors 65a and 65b are driven.

<Both motion switching mechanism>
Next, a switching operation between the composition determination operation by OVF and the composition determination operation by EVF will be described.

  FIG. 7 is a top view of the imaging apparatus 1, and FIG. 8 is a schematic diagram illustrating a drive mechanism (angle changing mechanism) of the mirror 65e. In FIG. 7, a part of the imaging device 1 is broken and an internal state is shown.

  As shown in FIG. 8, the rectangular mirror 65e is provided so as to be rotatable about an axis substantially parallel to the longitudinal direction. Specifically, on the lower end side of the mirror 65e, the shaft member 88 passes through a through hole provided along the lower side of the rectangular mirror 65e and is fixed to the mirror 65e. The shaft member 88 is pivotally supported at both ends thereof so that the mirror 65e can rotate (swing).

  A switching dial 87 and a rotor 92 are fixed to the shaft member 88.

  As shown in FIGS. 7 and 1, a part of the switching dial 87 protrudes from the outer surface of the camera body 2 of the imaging device 1, and the photographer switches using the protruding part of the switching dial 87. The dial 87 can be rotated. In order to prevent dust and the like from entering the inside of the apparatus from the switching dial 87 portion, a partition wall 96 is provided so as to surround the switching dial 87.

  FIG. 9 is a diagram showing a configuration near the switching dial 87. As shown in FIG. 9, two notches Na and Nb are provided on the outer peripheral portion of the switching dial 87. An elastic member 91 is provided on the outer periphery of the switching dial 87. The protrusion 91a provided at the tip of the elastic member 91 is pressed against the outer peripheral surface of the switching dial 87 with an appropriate elastic force, and is relatively moved along the outer peripheral surface with the rotational movement of the switching dial 87. Is possible. Moreover, the protrusion 91a of the elastic member 91 can fix the position of the switching dial 87 in the rotational direction by selectively engaging one of the two notches Na and Nb. When the protruding portion 91a of the elastic member 91 is engaged with the cutout portion Na, a composition determining operation by OVF is performed. Further, when the protruding portion 91a of the elastic member 91 is engaged with the notch Nb, the composition determination operation by EVF is performed.

  The photographer operates the switching dial 87 to rotate the mirror 65e in the direction of the arrow AR1 and engage the protruding portion 91a of the elastic member 91 with the cutout portion Nb to perform the composition determination operation by EVF. Is possible. Conversely, by operating the switching dial 87 and rotating the mirror 65e in the direction of the arrow AR2, the composition determining operation by OVF can be performed by engaging the protruding portion 91a of the elastic member 91 with the cutout portion Na. It becomes possible.

  Further, a rotor 92 and a detector 93 are provided to detect the angle of the mirror 65e. As shown in FIG. 10, in the composition determination operation by OVF, the two electrical connectors 94a and 94b of the detector 93 are in contact with each other and are in a conductive state (ON state). On the other hand, as shown in FIG. 11, in the composition determination operation by EVF, the force in the direction of the arrow AR3 is applied to the electrical connector 94b by the protrusion 92b of the rotor 92 as the shaft member 88 rotates. The electrical connector 94b is deformed rightward in FIG. As a result, the electrical connector 94b is separated from the electrical connector 94a, and the electrical connectors 94a and 94b are turned off (off state). The detector 93 detects the angle of the mirror 65e by detecting these two states (on state and off state).

  The overall control unit 101 determines whether to perform the composition determination operation using the OVF or the composition determination operation using the EVF based on the detection state of the detector 93. Specifically, when the ON state of the detector 93 is detected, it is determined that the composition determination operation by the OVF should be performed, power supply to the image sensor 7 is stopped, and the rear monitor 12 is not displayed. Process. On the other hand, when the off state of the detector 93 is detected, it is determined that the composition determination operation by the EVF is to be performed, power is supplied to the image sensor 7, and a live view image is displayed on the rear monitor 12. I do.

<Photometric processing>
Next, a photometric process during the composition determination operation by EVF and a photometry process during the composition determination operation by OVF will be described.

  FIG. 12 is an enlarged cross-sectional view showing an internal configuration in the vicinity of the pentamirror 65. As shown in FIG. 12, an eyepiece 67 and a finder window 10 are provided on the optical path PA. On the other hand, a beam splitter 71, an imaging lens 69, and an image sensor 7 are provided on the optical path PB.

  The beam splitter 71 has an optical path changing function for changing the traveling direction of light (in other words, the traveling path of light (optical path)). Specifically, the beam splitter 71 is disposed on the optical path PB, and changes the path of light traveling on the optical path PB (specifically, the light reflected by the reflecting surface 65e) upward by about 90 degrees. . The imaging lens 69 and the image sensor 7 are arranged on the optical path PB (PB2) after the traveling direction is changed by the beam splitter 71, and the luminous flux after the traveling direction is changed by the beam splitter 71 is the imaging lens 69. And forms an image on the image sensor 7.

  In the composition determination operation by EVF, the reflecting surface 65e is disposed at the position P1, and the path of the observation light beam is the optical path PB. At this time, a photographed image is generated based on the subject image that travels on the optical path PB and forms an image on the image sensor 7 via the beam splitter 71 and the imaging lens 69. Then, live view display is performed using the captured image, and photometric processing is also performed using the same captured image. For example, a photometric process for dividing a photographed image by the image sensor 7 into a plurality of (for example, 8 (horizontal) × 5 (vertical) = 40) photometric blocks and calculating a received light amount in each photometric block is executed. Further, processing (automatic exposure adjustment processing) for determining photographing parameters (aperture value, shutter speed, etc.) that realizes appropriate brightness is performed based on the photometric result.

  On the other hand, in the composition determination operation by OVF, the reflecting surface 65e is disposed at the position P2 (position indicated by a broken line in FIG. 12), and the path of the observation light beam becomes the optical path PA. At this time, the subject image is visually recognized through the finder window 10 and photometric processing is performed using the photometric sensor 79 disposed in the vicinity of the optical path PA. The photometric sensor 79 receives the light beam transmitted through the beam splitter 71 disposed in the vicinity of the optical path PA through the imaging lens 72 and performs photometric processing.

  The photometric sensor 79 sandwiches the focusing screen 63 and receives the light traveling along the optical path PE indicated by the dotted line in FIG. 12, specifically, the light traveling in the vicinity of the optical path PA and transmitted through the beam splitter 71. Here, the beam splitter 71 exists on the optical path PB as well as on the optical path PE, but the light beam traveling on the optical path PE passes through the beam splitter 71 and reaches the photometric sensor 79. The photometric sensor 79 receives a light beam traveling in the optical path PE, thereby obtaining a subject image similar to the subject image of the observation light beam traveling in the optical path PA (in other words, a light image similar to the subject image to be photographed), Specifically, a light image obtained by viewing a subject related to the subject image received through the finder window 10 from a slightly different angle (slightly obliquely) is received.

  Then, photometric processing based on the amount of light received by the photometric sensor 79 is appropriately realized. For example, photometric processing for calculating the amount of received light in each of a plurality of (for example, 40) photometric units in the photometric sensor 79 is executed. Further, processing (automatic exposure adjustment processing) for determining photographing parameters (aperture value, shutter speed, etc.) that realizes appropriate brightness is performed based on the photometric result.

  In the composition positioning operation by OVF, since the path of the observation light beam is the optical path PA, an appropriate subject image is not formed on the image sensor 7. Therefore, when the photometric sensor 79 as described above is not provided, it is difficult to realize appropriate photometric processing at the time of composition positioning operation by OVF.

<Defective Pixel Detection Operation in the Image Sensor 7>
In the imaging apparatus 1, the photographing operation is performed as described above.

  By the way, as described above, acquired defective pixels may be generated in the image sensor 7 due to the influence of cosmic rays or the like. If an image based on such defective pixels is displayed as it is, the live view image is deteriorated.

  Therefore, in this embodiment, a technique for appropriately detecting defective pixels of the image sensor 7 and suppressing deterioration of an image acquired by the image sensor 7 will be further described.

  Specifically, in the EVF mode, when the release button 11 is pressed by the operator and an imaging instruction input is received, the imaging apparatus 1 further moves the main mirror 61 to the mirror up position (focus point) in response to the imaging instruction input. It moves to PS1 (also referred to as an opposing position of the plate 63) (see FIG. 13). When the upper space SU in the internal space of the imaging device 1 is in a light shielding state due to the movement of the main mirror 61 to the mirror up position, the imaging device 1 exposes the imaging element 7 provided in the upper space SU in the light shielding state. An image is acquired, and defective pixels of the image sensor 7 are detected using the exposure image.

  FIG. 13 is a diagram illustrating an internal configuration of the imaging apparatus 1 at the time of shooting in EVF mode (during an exposure operation by the imaging device 5). As shown in FIG. 5 described above, in this embodiment, the eyepiece shutter 16 is already closed in the EVF system composition determination operation (before the release button 11 is pressed), and the light is incident from the viewfinder window 10 to the space SU. It is blocked. Therefore, by further moving the main mirror 61 to the mirror-up position to cover the focusing screen 63 with the main mirror 61, it is possible to easily achieve the light shielding state of the upper space SU. That is, it is not necessary to accompany the operation of closing the eyepiece shutter 16 in accordance with the photographing instruction input.

  14 and 15 are partially enlarged views showing the state near the focusing screen 63. FIG. FIG. 14 shows a mirror-down state, and FIG. 15 shows a mirror-up state. FIG. 16 is an exploded perspective view of the focusing screen 63, the holder 64, and the like. 14 to 16, illustration of the partition 66, the sub mirror 62, and the like is omitted for simplification.

  Here, the internal space of the imaging device 1 is divided into an upper space SU and a lower space SL by a partition wall 66 (see FIG. 4 and FIG. 13 and the like) provided at a position similar to the position of the focusing screen 63 in the height direction. It is separated by. Among them, the upper space SU is formed as a closed space covered with the camera body 2 (including the partition wall 66 and the like), and in a portion excluding the focal plane 63 and the finder window 10 from the outside of the upper space SU. It is configured so that light does not enter the inside. In the lower space SL, a main mirror 61, an image sensor 5 and the like are provided.

  As shown in FIG. 13 and the like, in this embodiment, a holder (holding member) 64 that holds the focusing screen 63 is fixed to a partition wall 66 inside the main body of the imaging apparatus 1. In other words, the focusing screen 63 is fixed and held on the main body of the imaging device 1 via the holder 64.

  As shown in FIG. 16 and the like, the holder 64 has an opening 64a at the center thereof, and has frame parts 64b on four sides surrounding the opening 64a.

  On the upper surface side of the frame portion 64b (in other words, on the pentamirror 65 side), a step portion is provided in accordance with the size (width, height, depth) of the focusing screen 63, and the focusing screen is placed on the step portion. 63 is fitted and held. As a result, the focusing screen 63 is fixedly disposed in the opening 64 a of the holder 64.

  Further, a substantially semi-cylindrical cushioning material 64c is provided on the lower surface side of the frame portion 64b (in other words, on the main mirror 61 side) so as to protrude toward the main mirror 61 side. Specifically, the cushioning material 64 c is provided over the entire circumference of the frame portion 64 b at a position surrounding the focusing screen 63. The buffer material 64c is formed of, for example, an elastic material such as rubber or a non-woven fabric.

  As shown in FIG. 15, when the main mirror 61 moves to the opposite position (mirror up position) PS1 close to the focusing screen 63, that is, during the mirror up operation (up operation), the main mirror 61 stops. It stops after contacting the cushioning material 64c immediately before the position. As a result, the impact received by the focusing screen 63 and the holder 64 from the main mirror 61 is reduced.

  Further, the buffer material 64c has a light shielding property. Then, as shown in FIG. 15, the main mirror 61 is moved to the mirror-up position PS1 (in other words, the main mirror 61 is close to the focusing screen 63 with a minute distance (see also FIG. 13). )), The cushioning material 64 c is in contact with the main mirror 61. At this time, the buffer material 64c fills the gap between the focusing screen 63 and the main mirror 61, and blocks the light from the main mirror 61 side so that the light from the main mirror 61 side does not enter the upper space SU. Yes. Thus, by making the buffer material 64c function as a light shielding member, the light shielding state of the upper space SU can be realized at a high level after the main mirror 61 is moved to the mirror up position.

  Thus, by providing the light-shielding cushioning material 64c in the vicinity of the focusing screen 63, the impact of the main mirror 61 on other members during the mirror-up operation is mitigated and the light-shielding in the upper space SU in the mirror-up state is reduced. It is possible to increase the degree.

  FIG. 17 is a flowchart showing a schematic operation of the imaging apparatus 1 according to the first embodiment. Hereinafter, the schematic operation of the imaging apparatus 1 in the shooting mode will be described with reference to FIG.

  As shown in FIG. 17, when the power is turned on, key sensing is performed to sense the presence or absence of operations related to various operation members (step SP1). Then, when it is detected by the key sensing that the release button 11 has been pressed down to the fully-pressed state S2, the process proceeds from step SP2 to step SP3 on the assumption that an imaging instruction input from the operator has been received. In step SP3 and subsequent steps, the EVF display on the rear monitor 12 is interrupted until the photographing operation in step S20 is completed.

  In step SP3, the main mirror 61 is moved to the mirror up position PS1 to enter the mirror up state. When it is confirmed that the EVF mode is set, the operation at step SP10 and the operation at step SP20 are further executed in this mirror-up state. On the other hand, when it is not the EVF mode (that is, when it is the OVF mode), the operation of step SP10 is not executed, and the operation of step SP20 is executed. In this embodiment, the operation of step SP10 and the operation of step SP20 are executed in parallel in order to increase the speed. However, the present invention is not limited to this, and the operation of step SP10 and the operation of step SP20 may be executed sequentially.

  In step SP10, an exposure operation and an image signal readout operation (step SP11) relating to the image sensor 7, a defective pixel detection operation (step SP12) of the image sensor 7, and a correction data generation operation and storage operation (step SP13) are performed. Executed.

  Specifically, in step SP11, first, an appropriate exposure time is set using the electronic shutter of the image sensor 7, and the exposure operation in the image sensor 7 is realized. Then, by reading out the electric charges accumulated in the exposure operation, the pixel value (gradation value) D (x, y) of each pixel PE (x, y) of the image sensor 7 is read out.

  In the next step SP12, it is determined whether or not the image value D (x, y) of each pixel is equal to or greater than the threshold value TH1 for white defect determination.

  In the mirror-up state, the space SU in which the image sensor 7 is arranged is in a light-shielded state, so that the image value D (x, y) of each pixel is essentially a very small value (ideally Is zero). However, a defective pixel having an abnormal pixel value (relatively large pixel value) may exist among the plurality of pixels in the image sensor 7. Such defective pixels are so-called “white scratches”. Therefore, here, it is determined whether or not each pixel is “white scratch” by using an appropriate threshold value TH1. Specifically, when the pixel value D (x, y) of a certain pixel is greater than or equal to the threshold value TH1, the pixel is determined as a defective pixel, and the pixel value D (x, y) of the pixel is less than the threshold value TH1. In this case, the pixel is determined as a normal pixel.

  In step SP13, correction data for correcting the pixel value of the defective pixel detected in step SP12 is generated and stored. For example, an average value Dave of pixel values of pixels of the same color adjacent to the defective pixel is calculated as correction data, and the average value and position information (address information) of the defective pixel are associated with each other to obtain a predetermined value of the imaging device 1. The data is stored in a storage area in a memory (nonvolatile memory (not shown) or the like). Further, the correction data is added to all correction data including the correction data already stored in the memory and stored in the memory. In order to improve data reading efficiency, it is preferable that all correction data is stored in a state of being sorted in the order of reading addresses.

  In step SP20, a still image recording operation by the image sensor 5 is executed.

  Specifically, first, in step SP21, the shutter (mechanical shutter) 4 is driven to expose the image sensor 5 over a predetermined exposure period, and the charges generated by the exposure are read out.

  Thereafter, in step SP22, the main mirror 61 is lowered to the mirror down position PS2 (see FIG. 14) and returned to the mirror down state. Note that the lowering operation of the main mirror 61 in step SP22 is controlled to be executed after the readout operation of each pixel of the image sensor 7 in step SP11 is completed.

  In step SP23, image processing related to the still image acquired in step SP21 is performed, and a captured image by the image sensor 5 is generated.

  As described above, the operation of generating the correction data of the defective pixel in the image sensor 7 is executed together with the operation of acquiring the captured image by the image sensor 5.

  After the operation of step SP20 is completed, the EVF display that was interrupted after step SP3 is resumed. Then, when performing the EVF display after resumption, a defective pixel correction operation using the correction data stored in step SP13 is executed.

  Specifically, by adopting the above correction data instead of the value read from the image sensor 7 as the pixel value of the pixel corresponding to the position information stored in step SP13, the pixel value of the pixel is changed. to correct. Specifically, when the position information (address information) of the pixel to be read matches the position information (address information) of the defective pixel stored in step SP13, the correction data stored in step SP13 (for example, Dave ) Is adopted as the pixel value after correction. As a result, “white scratches” in the image captured by the image sensor 7 can be eliminated.

  As described above, according to the imaging apparatus 1 in the first embodiment, the main mirror 61 is moved to the mirror-up position PS1, the space SU including the imaging element 7 is set in the light shielding state, and imaging is performed using the light shielding state. A defective pixel of the element 7 is detected. Therefore, defective pixels of the image sensor 7 are appropriately detected, and it is possible to suppress deterioration of an image acquired by the image sensor 7.

  In particular, in response to an imaging instruction input from the operator, the main mirror 61 is in the mirror-up state, the space SU is in the light-shielding state, and defective pixels of the image sensor 7 are detected. That is, defective pixels of the image sensor 7 are automatically detected during the photographing operation. Therefore, it is possible to detect a defective pixel of the image sensor 7 without performing a special operation by the user.

  Note that during the mirror-up period, the subject image does not reach the image sensor 7, so that live view display cannot be realized. Therefore, from the viewpoint of reducing power consumption, it is preferable to stop the display on the rear monitor 12 and stop the energization to the image sensor 7. In contrast, in this embodiment, the operation of step SP10 (particularly step SP11) is performed while intentionally maintaining the energization state of the image sensor 7.

<2. Second Embodiment>
The second embodiment is a modification of the first embodiment. Below, it demonstrates centering on difference with 1st Embodiment.

  In the first embodiment, the case where a defective pixel detection operation or the like is performed when an imaging instruction input is received in the EVF mode is exemplified. In the imaging apparatus 1 (1B) according to the second embodiment, a case where a defective pixel detection operation or the like is performed not only in the EVF mode but also in the OVF mode is illustrated.

  FIG. 18 is a flowchart showing a schematic operation according to the second embodiment. As shown in FIG. 18, in the second embodiment, the operation of step SP10 is executed even in the OVF mode.

  Specifically, if it is determined in step SP4 that the OVF mode is the OVF mode, the process proceeds to step SP5. In step SP5, as shown in FIG. 19, the eyepiece shutter 16 is closed and the power supply to the image sensor 7 is started. As a result, the image sensor 7 that has been turned off in order to save power in the OVF mode is turned on. FIG. 19 shows a state in which the eyepiece shutter 16 is closed after a shooting instruction is input by the operator in the OVF mode.

  Thereafter, the operation of step SP10 and the operation of step SP20 are executed. In step SP8, when it is determined that the OVF mode is set, the process proceeds to step SP9, where the eyepiece shutter 16 is opened again, and power supply to the image sensor 7 is stopped again to reduce power consumption.

  In the EVF mode, the same operation as in the first embodiment described above is executed.

  According to the operation shown in FIG. 18, even in the OVF mode, by closing the eyepiece shutter 16 and moving the main mirror 61 to the mirror-up position PS1, a light-shielding state related to the upper space SU is formed, and the image sensor 7 It is possible to execute the defective pixel detection operation.

<3. Third Embodiment>
The third embodiment is a modification of the first embodiment. Below, it demonstrates centering on difference with 1st Embodiment.

  The third embodiment exemplifies a case where a defective pixel detection operation or the like is executed in the cleaning mode (not the shooting mode). In this cleaning mode, the operator performs an operation of cleaning the image sensor 5 as the main image sensor and the lower space SL including the image sensor 5. In the third embodiment, a pixel detection operation related to the image sensor 7 is executed during the cleaning operation. Note that the lower space SL is a space below the focusing screen 63 and the partition wall 66 in the internal space of the imaging device 1, and is also expressed as a space outside the upper space SU.

  FIG. 20 is a flowchart showing a schematic operation according to the third embodiment. In FIG. 20, it is assumed that the mode has been switched to the cleaning mode in advance by the operation of the operator before the process of step SP51.

  As shown in FIG. 20, key sensing is performed to sense the presence / absence of operations related to various operation members (step SP51). Then, when it is detected by the key sensing that the release button 11 has been pressed down to the fully pressed state S2, the process proceeds from step SP52 to step SP53, assuming that the mirror up instruction input from the operator has been received. Note that the instruction to press the release button 11 detected at steps SP51 and SP52 (mirror up instruction input) is also expressed as an instruction input to start the cleaning operation.

  Then, the mirror-up operation (step SP53) of the main mirror 61 is executed and the mechanical shutter 4 is opened (step SP55). In this state, the operator can perform a cleaning operation. In step SP54, the eyepiece shutter 16 is closed and the image sensor 7 is energized. This makes it possible to execute a defective pixel detection operation and the like related to the image sensor 7 that is a sub-image sensor during the cleaning operation. Thereafter, a defective pixel detection operation or the like (step SP10) of the image sensor 7 is performed. During this cleaning operation, power supply to the image sensor 5 that is the main image sensor is stopped, and the image sensor 5 is in a non-energized state.

  After that, key sensing is performed, and when it is detected that the release button 11 is pressed down again to the fully-pressed state S2 by the operation of the operator (steps SP61 and SP62), it is assumed that the cleaning operation is completed and the step is completed. Processing after SP63 is executed. Specifically, the mirror down operation of the main mirror 61 is executed and the mechanical shutter 4 is closed (steps SP64 and SP65). In step SP65, the eyepiece shutter 16 is opened again, and power supply to the image sensor 7 is stopped again to reduce power consumption. Note that the second instruction to press the release button 11 (mirror down instruction input) detected in steps SP61 and SP62 is also expressed as an instruction input to end the cleaning operation.

  As described above, by using the light-shielding state of the space SU in the cleaning mode, it is possible to execute defective pixel detection and the like of the image sensor 7 arranged in the space SU.

  In particular, in the general cleaning mode, the power supply to the image pickup device 7 is stopped, whereas in the cleaning mode according to this embodiment, the image pickup device 7 is intentionally turned on so that the image pickup device 7 is turned on. 7 defective pixel detection operation or the like (step SP10) can be executed.

<4. Modification>
Although the embodiments of the present invention have been described above, the present invention is not limited to the contents described above.

  For example, in each of the above embodiments, the case where the main mirror 61 is close to the focusing screen 63 at the mirror-up position is illustrated, but the present invention is not limited to this, and the main mirror 61 contacts the focusing screen 63 at the mirror-up position. It may be.

  In the first and second embodiments, the case where the defective pixel detection operation or the like is always performed every time a shooting instruction input is generated is illustrated, but the present invention is not limited to this.

  For example, a defective pixel detection operation or the like may be performed when responding to the first imaging instruction input after the imaging apparatus 1 is turned on again. According to this, the frequency of defective pixel detection can be suppressed.

  Further, in the first and second embodiments, the case where the defective pixel detection operation or the like is performed in response to the photographing instruction input is illustrated, but the present invention is not limited to this. For example, a defective pixel detection operation or the like may be performed every time the passage of a predetermined period is detected (in short, periodically). More specifically, the defective pixel detection operation or the like may be forcibly executed when the power is turned on for the first time after a predetermined period (for example, one month) has elapsed since the previous defective pixel detection operation was performed.

  In each of the above embodiments, the case where the main mirror 61 is brought into the mirror-up state and the eyepiece shutter 16 is closed to place the existence space SU of the image sensor 7 in the light-shielding state is exemplified, but the present invention is not limited thereto.

  For example, instead of the image pickup apparatus 1 automatically closing the eyepiece shutter 16, the operator may attach the eyepiece cover 17 to the image pickup apparatus 1 as shown in FIG. In a state where the eyepiece cover 17 is disposed so as to cover the finder window 10, the main mirror 61 moves to the mirror up position PS <b> 1, whereby the light shielding state of the upper space SU can be formed. FIG. 21 is a diagram illustrating a state in which an eyepiece cover 17 of a type attached to the strap belt 18 is attached so as to cover the finder window 10 on the back side of the imaging device 1.

  More specifically, for example, in the cleaning mode, a message indicating that the eyepiece cover 17 should be attached may be displayed on the display unit such as the rear monitor 12 so as to encourage the operator to attach the eyepiece cover 17. Then, when a cleaning start instruction is input after the eyepiece cover 17 is attached by the operator, the imaging device 1 flips up the main mirror 61 to bring it into a mirror-up state, and performs the above-described defective pixel detection operation and the like. be able to.

  Alternatively, the light shielding state of the space SU may be realized by covering the finder window 10 with an operator's hand (or near the eye part of the operator's face) instead of the eyepiece cover 17 as described above.

  The “light shielding state” of the space SU does not have to be a complete light shielding state. The “light-blocking state” of the space SU is sufficient if it is a light-blocking state in which white flaw detection is possible. For example, it is sufficient if the brightness of the space SU is a light-shielding state in which the brightness is below a predetermined level set appropriately.

  In these cases, it is also assumed that the light shielding state of the space SU is not actually realized only by moving the main mirror 61 to the mirror-up position. Therefore, it is preferable to confirm that the light shielding state of the space SU is realized as follows.

  For example, an average value of all the pixels of the image sensor 7 is obtained, and when the average value of all the pixels is equal to or less than the predetermined threshold value TH2, it may be determined that the light shielding state of the space SU is realized. According to this, it is possible to detect whether or not the light shielding state of the space SU is realized by detecting the overall brightness in the image sensor 7. Therefore, it can be ensured that the defective pixel detection operation of the image sensor 7 is performed in a light-shielded state.

  Or you may make it confirm that space SU is a light-shielding state by confirming that the brightness of space SU is below a predetermined level based on the photometry result of the photometry sensor 79. FIG.

  Further, depending on the situation, even if the finder window 10 is not covered with any object or the like, the light shielding state of the space SU may be formed by the main mirror 61 moving to the mirror up position. For example, in night scene shooting, when the vicinity of the imaging device 1 is dark and only the subject is bright, the main mirror 61 is moved to the mirror-up position so that the light collected by the shooting lens unit 3 does not enter the space SU. Only in some cases, the light shielding state of the space SU may be formed.

  Considering such circumstances, an illuminance meter is arranged on the imaging device 1 (for example, the outer surface side of the imaging device 1), and a defective pixel detection operation is performed according to the measurement result of the illuminance meter. Good. More specifically, when it is determined that the intensity of the ambient light measured by the illuminometer is equal to or lower than a predetermined level, the main mirror 61 is moved to the mirror-up position and a defective pixel detection operation is performed. That's fine. If the main mirror 61 is moved to the mirror-up position while the vicinity of the imaging device 1 is dark, the light shielding state of the space SU can be more reliably realized. Therefore, it can be ensured that the defective pixel detection operation is executed under suitable conditions. Alternatively, similarly to the above, based on the photometric result of the image sensor 7 or the photometric sensor 79, it is confirmed that the brightness of the space SU is equal to or lower than a predetermined level, that is, the space SU is in a light-shielding state. A detection operation may be performed.

  In each of the above embodiments, the case where the holder (holding member) 64 is provided independently of the partition wall 66 is illustrated, but the present invention is not limited to this. For example, a part of the partition wall 66 may function as a holding member that holds the focusing screen 63.

  Moreover, in each said embodiment, although the case where the buffer material 64c was arrange | positioned at the holder 64 was illustrated, it is not limited to this. For example, the buffer material 64c may be disposed on the focusing screen 63 instead of the holder 64. FIG. 22 is a diagram showing such a modification. In FIG. 22, the buffer material 64 c is disposed directly on the main reflection surface side of the focusing screen 63. Specifically, the buffer material 64 c is provided on the peripheral portion of the focusing screen 63 so as to surround the translucent portion 63 a at the center of the focusing screen 63 on the main reflection surface side of the focusing screen 63.

  In each of the above-described embodiments, the case where the angle of the mirror 65e is changed using the physical operation force of the photographer (ie, manually) is illustrated, but the present invention is not limited to this. For example, the angle of the mirror 65e or the like may be changed using a driving device such as a motor.

  In each of the above embodiments, the case where EVF display is realized by changing the reflection angle of the mirror 65e and changing the path of the observation light beam is exemplified, but the present invention is not limited to this. For example, in the imaging apparatus that realizes live view display by providing a movable reflection mirror that can advance and retreat with respect to the optical path of the subject image in the optical path in the vicinity of the eyepiece lens 67 of the finder optical system as in the above-described conventional technology The idea of the present invention may be applied.

  Or you may make it apply the idea of this invention with respect to the apparatus which implement | achieves EVF display by the method different from the above. For example, a beam splitter is provided between the pentamirror 65 and the finder window 10, and the observation light beam is divided into a component toward the image sensor 7 for live view and a component toward the finder window 10 by the beam splitter. By doing so, an imaging apparatus that realizes EVF display can be configured. In such an imaging apparatus, the above idea may be applied to detect defective pixels of the imaging element 7 in a light-shielded state.

  In each of the above embodiments, the case where the idea of the present invention is applied to a digital camera has been illustrated. However, the present invention is not limited thereto, and the idea of the present invention can also be applied to a film-type camera. Specifically, the image pickup surface of the film may be disposed at the position of the image pickup surface of the image pickup device 5 without providing the image pickup device 5.

It is a front external view of an imaging device. It is a back external view of an imaging device. It is a block diagram which shows the function structure of an imaging device. 2 is a cross-sectional view of the imaging apparatus (during OVF composition determination operation). FIG. It is sectional drawing (at the time of composition determination operation | movement of an EVF system) of an imaging device. It is sectional drawing (at the time of exposure operation after composition determination operation | movement of an OVF system) of an imaging device. It is a top view of an imaging device. It is the schematic which shows the drive mechanism (angle changing mechanism) of a mirror. It is a figure which shows the structure of a switching dial vicinity. It is a figure which shows the detection state in the composition determination operation | movement of an OVF system. It is a figure which shows the detection state in the composition determination operation | movement of an EVF system. It is a partially enlarged view of the vicinity of the pentamirror. It is sectional drawing (at the time of exposure operation after composition determination operation | movement of an EVF system) of an imaging device. It is a partially enlarged view showing a state in the vicinity of the focusing screen (mirror down state). It is a partially enlarged view showing a state in the vicinity of the focusing screen (mirror up state). It is a disassembled perspective view of a holder etc. 3 is a flowchart illustrating a schematic operation of the imaging apparatus according to the first embodiment. It is a flowchart which shows schematic operation | movement of the imaging device which concerns on 2nd Embodiment. It is sectional drawing (at the time of exposure operation after composition determination operation | movement of an OVF system) of the imaging device which concerns on 2nd Embodiment. 12 is a flowchart illustrating a schematic operation of the imaging apparatus according to the third embodiment. It is an external appearance rear view which shows the imaging device with which the eyepiece cover was mounted | worn. It is sectional drawing of the imaging device which concerns on a modification.

Explanation of symbols

1, 1A, 1B Image pickup device 4 Mechanical shutter 5, 7 Image sensor 10 Viewfinder window 11 Release button 12 Rear monitor 16 Eyepiece shutter 17 Eyepiece cover 61 Main mirror 62 Sub mirror 63 Focus plate 64 Holder 64a Opening 64b Frame portion 64c Buffer material 65 Pentamirror

Claims (9)

An imaging device comprising:
A viewfinder optical system that guides an observation light beam, which is a light beam from the imaging optical system and reflected by the main reflecting surface, to the finder window;
A first image sensor that receives the observation beam and generates an image signal;
The main reflection surface is moved to a mirror-up position so that a predetermined space including the first image sensor is shielded, and an exposure image of the first image sensor in the light shield state is acquired to obtain the first image. Control means for detecting defective pixels of the element;
An imaging apparatus comprising: The imaging apparatus according to claim 1,
The image pickup apparatus, wherein the control unit forms the light shielding state by moving the main reflection surface to the mirror up position in a state where the eyepiece shutter of the finder optical system is closed. The imaging apparatus according to claim 1,
The control unit forms the light-shielding state by closing an eyepiece shutter of the finder optical system and moving the main reflection surface to the mirror up position. The imaging apparatus according to claim 1,
The light-shielding state is formed by moving the main reflection surface to the mirror-up position in a state where an eyepiece cover is disposed so as to cover the finder window. The imaging apparatus according to claim 1,
A light-shielding cushioning material provided on the main reflecting surface side of the focusing screen;
Further comprising
The image pickup apparatus according to claim 1, wherein the control unit forms the light shielding state by moving the main reflection surface to a mirror up position that is close to the focusing screen and contacts the light shielding buffer. The imaging apparatus according to claim 1,
A holding member having an opening and holding the focusing screen in the opening;
A light-shielding cushioning material provided on the main reflecting surface side of the holding member;
Further comprising
The image pickup apparatus according to claim 1, wherein the control unit forms the light shielding state by moving the main reflection surface to a mirror up position that is close to the focusing screen and contacts the light shielding buffer. The imaging apparatus according to claim 1,
In response to an imaging instruction input from an operator, the control means moves the main reflecting surface to the mirror-up position so that the predetermined space is in the light-shielding state, and the defective pixel of the first image sensor. An image pickup apparatus for detecting The imaging apparatus according to claim 7,
In response to the first photographing instruction input after the power is turned on again, the control means moves the main reflecting surface to the mirror-up position so that the predetermined space is in the light-shielding state, and the first image sensor. An imaging device characterized by detecting defective pixels. The imaging apparatus according to claim 1,
The control means moves the main reflecting surface to the mirror-up position and moves the predetermined space in a cleaning mode for cleaning an internal space that includes the second image sensor and is different from the predetermined space. An imaging apparatus characterized by detecting the defective pixel of the first image sensor while setting the light shielding state and energizing the first image sensor.

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