JP2008298986A - Imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging apparatus having more simple constitution, having quick responsiveness in switching between an exposure condition and a non-exposure condition for an imaging device, and achieving miniaturization. <P>SOLUTION: A single lens reflex camera 10 that is the imaging apparatus includes: the imaging device 5 having a light receiving surface 5a; a photographic lens 1 that is an optical system for forming a subject image by making subject luminous flux incident on the light receiving surface 5a of the imaging device 5; an AF sensor part 6 that is a detector for detecting characteristic showing a focusing condition that is optical characteristic of the subject luminous flux; and a rotating plate 2 that is a plate-like rotating body having an aperture part 2a in a first area for transmitting the subject luminous flux and a reflection mirror for a sensor 3 in a second area for reflecting the subject luminous flux and making it incident on the detector, and rotating on a plane crossing with the optical axis of the luminous flux, to make conditions corresponding to the first area and the second area. By the rotation of the rotating plate 2, an AF detection condition and an imaging device exposure condition are switched. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a structure of an imaging apparatus that captures a subject image using an imaging element.

  In a single-lens reflex camera which is an image pickup apparatus using a conventional image sensor, for example, a single-lens reflex camera 100 disclosed in Patent Document 1 is a configuration diagram (outline) shown in a cross section along the optical axis in FIG. The photographic lens 101 that can be attached and detached on the optical axis (O) of the photographic lens, the oscillating movable mirror 102 composed of a half mirror having a sub mirror 102a, the shutter 103, the image sensor 104, and the upper side of the optical axis. Further, a screen 105, a pentaprism 106, an eyepiece lens 107, and an AF sensor unit 108 are provided below the optical axis.

The movable mirror 102 is supported by a mirror shaft 102b extending left and right along a plane orthogonal to the optical axis in a state in which the movable mirror 102 is urged by a spring so as to be able to open and close (swing). Then, when the power is turned on, during viewfinder observation, during AF, it is rotationally driven to an optical path entry position (imaging element non-exposure state) inclined in the photographing optical path and retracted from the photographing optical path during exposure (imaging element exposure state) Is driven to rotate.
JP-A 61-46941

  However, in the conventional single-lens reflex camera, the swing drive speed of the movable mirror 102 itself is limited, and the continuous shooting speed in high-speed continuous shooting is limited. In recent years, an image sensor capable of high-speed processing capable of continuous shooting at 10 frames / second or more has been developed, and it is considered difficult to cope with such an image sensor using the conventional movable mirror driving mechanism.

  In addition, the response operation when turning from the retracted position to the optical path entry position is delayed. Specifically, a bouncing occurs because the movable mirror stops suddenly, and it is difficult to start the AF process quickly.

  Furthermore, since the movable mirror 102 needs to swing and move as described above, the space occupied for the movable mirror 102 is large and the camera can be downsized.

  The present invention has been made in order to solve the above-described problem. In an imaging apparatus using an imaging device, the imaging device has a simpler configuration, and a response for switching between an exposure state and an unexposed state of the imaging device. An object of the present invention is to provide an imaging device that is quick and can be made compact.

  According to a first aspect of the present invention, an imaging device, an optical system for causing a subject light beam to be incident on a light receiving surface of the image sensor and generating a subject image, and detection for detecting optical characteristics of the subject light beam. And a first region that transmits the subject light beam and a second region that reflects the subject light beam and enters the detector, and rotates on a plane that intersects the optical axis of the light beam. A plate-like rotating body that generates a state corresponding to each of the first region and the second region.

  The imaging device according to a second aspect of the present invention is the imaging device according to the first aspect, wherein the plate-like rotating body rotates around an axis parallel to the optical axis.

  According to a third aspect of the present invention, in the imaging apparatus according to the first aspect, the plate-like rotating body rotates about an axis having a constant inclination of less than 90 degrees with respect to the optical axis.

  The imaging apparatus according to a fourth aspect of the present invention is the imaging apparatus according to the first aspect, further comprising a finder optical system, wherein the plate-like rotating body guides the subject light flux to the finder optical system. have.

  According to a fifth aspect of the present invention, in the imaging device according to the first aspect, the detector detects a focused state of the image of the subject luminous flux.

  The imaging device according to a sixth aspect of the present invention is the imaging device according to the first aspect, wherein the detector detects the luminance of the subject light beam or detects the in-focus state.

  According to a seventh aspect of the present invention, there is provided the imaging device according to the first aspect, wherein the plate-like rotating body has the subject image formed by the subject luminous flux on a plane including a light receiving corresponding surface corresponding to the light receiving surface. The shape of the first region is formed such that the region in which the is formed is larger than the region of the light receiving corresponding surface corresponding to the light receiving surface.

  The imaging device according to an eighth aspect of the present invention is the imaging device according to the first aspect, wherein the plate-like rotating body has a side edge portion of the first region facing in a radial direction passing through its rotation axis. It has a shape corresponding to the shape of the side edge of the light receiving surface corresponding to the light receiving surface.

  The imaging device according to a ninth aspect of the present invention is the imaging device according to the first aspect, wherein the plate-shaped rotating body is at least one of the side edges of the first region facing each other in the direction around the rotation axis thereof. Has a shape corresponding to the shape of the side edge of the light receiving surface corresponding to the light receiving surface.

  According to a tenth aspect of the present invention, in the imaging device according to the first aspect, the plate-like rotator has a side edge portion of the first region facing on a straight line passing through its rotation axis. It has a shape corresponding to a concentric circle around the rotation axis.

  The imaging apparatus according to an eleventh aspect of the present invention is the imaging apparatus according to the first aspect, wherein the plate-like rotating body rotates at a side edge of the first region facing in the direction around its own rotation axis. It is located on two different straight lines passing through the axis.

  An imaging apparatus according to a twelfth aspect of the present invention is the imaging apparatus according to the first aspect, further comprising a control unit that synchronizes the rotation of the plate-like rotator and the imaging operation of the subject image by the imaging element. To do.

  The image pickup apparatus according to a thirteenth aspect of the present invention is the image pickup apparatus according to the first aspect, further comprising a shutter and a control unit that synchronizes the rotation of the plate-like rotating body and the operation of the shirter.

  According to a fourteenth aspect of the present invention, in the imaging apparatus according to the first aspect, the plate-like rotating body is rotated by a stepping motor.

  According to a fifteenth aspect of the present invention, in the imaging apparatus according to the first aspect, the plate-like rotating body is provided with a balance weight for balancing the weight of the plate-like rotating body.

  An imaging device according to a sixteenth aspect of the present invention is the imaging device according to the first aspect, wherein the plate-like rotating body is formed with a structure that reduces air resistance due to rotation in the vicinity of the second region. .

  According to a seventeenth aspect of the present invention, in the imaging device according to the fourth aspect, the plate-like rotating body is formed with a structure for reducing air resistance due to rotation in the vicinity of the third region. The imaging apparatus according to claim 3.

  An image pickup apparatus according to claim 18 of the present invention is an image pickup device, an optical system that generates a subject image related to a subject light beam incident on a light receiving surface of the image pickup device, and a detector that detects optical characteristics of the image by the subject light beam. And a first region that transmits the subject image and a second region that reflects the subject image and makes it incident on the detector, and is orthogonal to the main surface of the plate. A plate-like rotator that generates a state corresponding to each of the first region and the second region by rotating about an axis is provided.

  According to the present invention, an image pickup apparatus using an image pickup device has a simpler configuration, has quick response to switching between an exposure state and a non-exposure state of the image pickup device, and can perform high-speed continuous shooting, for example. Thus, an imaging apparatus that can be made compact can be provided.

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

  1 and 2 are cross-sectional views along the optical axis showing the main configuration of the single-lens reflex camera that is the image pickup apparatus of the first embodiment of the present invention. FIG. 1 shows AF ranging (for autofocusing). FIG. 2 shows the exposure state. FIG. 3 is a front view of a rotating plate applied to the single-lens reflex camera.

  The optical axis of the photographing lens (lens optical axis) is indicated by O in the figure, and in the following description, the subject side of the optical axis is the front and the imaging side is the rear.

  The single-lens reflex camera 10 of the present embodiment includes a photographic lens 1 that can be attached to and detached from the camera body as shown in FIGS. 1 and 2, and a lens optical axis in order from the subject side behind the photographic lens 1 as a member built in the camera body. A rotation plate 2 as a plate-like rotator disposed along the shutter, a shutter 4 and an image sensor 5, and an AF sensor unit 6 as a detector disposed below the lens optical axis; A drive motor 7 and a control unit 8 are provided.

  The photographing lens 1 is an optical system that takes in a subject light flux and forms a subject image on the light receiving surface 5 a of the image sensor 5.

  The rotating plate 2 has a circular main plane orthogonal to the lens optical axis, is eccentric to the lower side of the lens optical axis, and is rotatably supported by a rotating shaft 7a parallel to the lens optical axis. The rotating plate 2 is rotationally driven through a rotating shaft 7a by a driving motor 7 composed of a stepping motor. A fan-shaped opening 2a is provided in the first area of the main plane on the rotating plate 2, and the sensor reflection mirror 3 is provided in the second area at the front side of the main plane and in the axially symmetric position of the opening 2a. It is arranged.

  The size of the opening 2a includes the imaging element light receiving surface equivalent area Ar that is a light receiving corresponding surface corresponding to the light receiving surface 5a of the image pickup element 5 at the position of the rotating plate on the optical path of the subject light beam (that is, the light reception). Larger than the surface equivalent area Ar). Specifically, the upper and lower edge lines of the opening 2a are formed by a circular arc of a rotational axis centering on the upper and lower sides of the image sensor light receiving surface equivalent area Ar, and the left and right edge lines are the light receiving surface equivalent area Ar. It is formed by a straight line that passes outside of the right and left sides of the lens and passes through the rotation axis.

  The reflection surface 3a of the sensor reflection mirror 3 is inclined with respect to the lens optical axis, and when the sensor reflection mirror 3 is at the lens optical axis position, the subject light flux is disposed below the AF sensor unit 6. Reflect towards

  The AF sensor unit 6 includes an optical unit and an AF distance sensor unit for detecting a focus state of a subject image that is an optical characteristic of the captured subject light flux.

  The controller 8 controls the rotation of the rotating plate 2 by controlling the driving motor 7, and in a state synchronized with the rotation of the rotating plate, the distance measuring state by the AF sensor unit 6 and the subject luminous flux through the opening 2a. Control is performed to switch between the exposure state in which the image pickup device 5 is exposed and transmitted. Further, during the exposure operation, shutter opening / closing control is performed in synchronization with the rotation of the rotating plate, and the imaging device is driven to capture the imaging signal of the subject image by the subject luminous flux and perform imaging processing.

  When single-shot photographing of a subject image is performed by the single-lens reflex camera 10 having the above-described configuration, first, when the power is turned on, the rotating plate 2 has the opening 2a positioned on the lens optical axis as shown in FIG. Rotate like so. In this state, the subject luminous flux passes through the shutter 4 in the open state and forms an image on the light receiving surface 5a of the image pickup device 5, and an image pickup signal of the subject image is output from the image pickup device 5 via a monitor unit (not shown). A subject image is observed (EVF state). As shown in FIG. 1, the sensor reflection mirror 3 is positioned on the lens optical axis by the first-stage operation of the release button. In this state, the subject luminous flux is reflected to the AF sensor unit 6 side. The AF sensor unit 6 detects a distance measurement signal indicating the focus state of the subject image by the subject light beam, and outputs the distance measurement signal to the control unit 8. The taking lens 1 is focused based on the distance measurement signal.

  Subsequently, the rotary plate 2 is rotationally driven by the second stage operation of the release button, and the opening 2a is positioned on the lens optical axis as shown in FIG. In this state, the shutter 4 is controlled to be opened and closed, and the subject light flux is imaged on the light receiving surface of the image sensor 5 to expose the image sensor 5. The imaging signal of the subject image is taken into the control unit 8 and imaging processing is executed.

  When continuous shooting is performed with the single-lens reflex camera 10, the rotating plate 2 is intermittently driven in accordance with the continuous shooting speed (frame / second). During rotation, when the sensor reflection mirror 3 is positioned on the lens optical axis, distance measurement is performed by the AF sensor unit 6, and when the opening 2a is positioned on the lens optical axis, exposure of the image sensor is performed. Is done. In this way, the operation of the image sensor is synchronized with the rotation of the rotating plate 2, and the subject luminous flux is effectively time-divided and utilized. During the exposure, the rotating plate 2 does not necessarily need to be stopped once as long as the opening 2a is positioned on the lens optical axis.

  According to the single-lens reflex camera 10 of this embodiment described above, the rotating plate 2 on which the sensor reflection mirror 3 is mounted instead of the oscillating movable mirror 102 applied in the conventional single-lens reflex camera 100 shown in FIG. Therefore, the rotating plate 2 can be accommodated in a narrow space in the optical path of the subject light flux. Further, since the rotary plate 2 is driven to rotate, there is no bounce phenomenon of the sensor reflection mirror 3 when stopped, and the distance measurement can be started quickly.

  At the time of continuous shooting, it is not necessary to swing the movable mirror as in the conventional single-lens reflex camera, it is only necessary to rotationally drive the rotating plate 2, no bounce phenomenon of the reflecting mirror 3 for the sensor, high speed, For example, continuous shooting at 10 frames / second or more is possible.

  The AF sensor unit 6 serving as a detector incorporates a luminance sensor unit that detects the luminance of the subject luminous flux in place of the AF distance sensor unit, detects the subject luminance by the sensor unit, and detects the shutter 4 and the image sensor. 5 may be configured to perform exposure control.

Next, modifications of the rotating plate 2 in the single-lens reflex camera 10 of the first embodiment will be described.
FIG. 4 is a front view of the rotating plate 2A of the first modification. The rotary plate 2A is provided with a rectangular opening 2Aa at an axially symmetric position of the sensor reflection mirror 3. The left and right edge lines 2Aa1 and 2Aa2 in the rotation direction of the opening 2Aa and the upper and lower edge lines 2Aa3 and 2Aa4 in the radial direction are parallel lines outside the outer shape of the image sensor light receiving surface equivalent area Ar. When this rotating plate 2A is applied, it is necessary to stop the rotating plate 2A during the exposure period.

  5 and 6 are front views of the rotating plate 2B of the second modified example, FIG. 5 shows a state at the start of exposure, and FIG. 6 shows a state at the end of exposure. The rotating plate 2B rotates counterclockwise during exposure.

  The rotary plate 2B is provided with an opening 2Ba in the first region and at the axially symmetric position of the sensor reflection mirror 3. The upper and lower edge lines in the radial direction of the opening 2Ba are arcs outside the outer shape of the image sensor light receiving surface equivalent area Ar. Further, the left edge line 2Ba1 in the rotation direction of the opening 2Ba is a parallel line outside the left edge line Ar1 of the image sensor light receiving surface equivalent area Ar when the rotating plate 2B is at the exposure start position shown in FIG. . On the other hand, the right edge line 2Ba2 in the rotation direction is a parallel line outside the right edge line Ar2 of the image sensor light receiving surface equivalent area Ar when the rotating plate 2B is at the exposure end position shown in FIG. Accordingly, at the start of exposure and at the end of exposure, the left and right edges of the light receiving surface 5a of the image sensor 5 are evenly covered without being inclined by the left edge line 2Ba1 or the left edge line 2Ba2 of the opening 2Ba. Become.

  When the rotating plate 2B of the present modification is applied, it is not necessary to stop the rotating plate 2B during the exposure period of the image sensor 5, and exposure can be performed in the rotated state. Further, since the upper and lower edges of the light receiving surface 5a of the image sensor 5 are evenly opened and covered, uneven exposure is less likely to occur.

Next, the single-lens reflex camera which is an imaging device of 2nd embodiment of this invention is demonstrated using FIGS.
7 to 9 are cross-sectional views along the optical axis showing the main configuration of the single-lens reflex camera that is the imaging apparatus of the present embodiment. FIG. 7 shows an optical viewfinder observation state, and FIG. FIG. 9 shows the distance (focusing state detection for autofocus) state, and FIG. 9 shows the exposure state. FIG. 10 is a front view of a rotating plate applied to the single-lens reflex camera.

  The single-lens reflex camera 20 according to the present embodiment includes a photographic lens 21 that can be attached to and detached from the camera body as shown in FIGS. 7 to 9, and a lens optical axis in order from the subject side behind the photographic lens 21 as a member built in the camera body. And a finder optical system (to be described later) disposed above the lens optical axis, and a lens optical axis. An AF sensor unit 30 as a detector, a drive motor 31, and a control unit 32.

  The taking lens 21 is an optical system that takes in a subject light flux and forms an image of the subject on the light receiving surface 26 a of the image sensor 26.

  The finder optical system includes a screen 27 disposed above the lens optical axis, a pentaprism 28 disposed on the screen 27, and an eyepiece lens 29 disposed behind the pentaprism 28.

  The AF sensor unit 30 includes an optical unit for detecting a focus state of a subject image, which is an optical characteristic of the captured subject light beam, and an AF distance sensor unit.

  The rotating plate 22 has a circular main plane orthogonal to the lens optical axis, is eccentric to the lower side of the lens optical axis, and is rotatably supported by a rotating shaft 31a parallel to the lens optical axis. It is rotationally driven via a rotating shaft 31a by a drive motor 31 comprising a motor. The main plane of the rotating plate 22 has an opening 22a in a first area in three directions around the rotation axis 31a, a sensor reflection mirror 23 on the front side of the second area, and the front side of the third area. A finder reflecting mirror 24 is disposed on the finder, and a balance weight 33 is secured to the outer diameter side of the opening 22a.

  The size of the opening 22a includes a size corresponding to the light receiving surface corresponding to the light receiving surface 26a corresponding to the light receiving surface 26a of the image pickup device 26 at the position of the rotating plate on the optical path of the subject light beam (that is, the image pickup device). Larger than the light receiving surface equivalent area Ar). Specifically, the upper and lower (radial direction) edge lines of the opening 22a are formed by an arc including the upper and lower sides of the image sensor light receiving surface equivalent area Ar, and the left and right (rotation direction) edge lines are the first embodiment described above. The left and right edge lines (FIG. 3) of the rotating plate 2 in FIG. 3 or the same shape as the rotating plate 2A of the first modified example. Furthermore, imaging is performed at the start and end of exposure in the same manner as in the rotation direction left and right edge lines 2Ba1 and 2Ba2 (FIGS. 5 and 6) of the opening 2Ba provided in the rotary plate 2B of the second modification to the rotary plate in the first embodiment. You may form with the line parallel to the right-and-left edge line of the element light-receiving surface equivalent area Ar.

  The reflection surface 23a of the sensor reflection mirror 23 is inclined with respect to the lens optical axis, and reflects the subject light beam toward the AF sensor unit 30 disposed below in a state where the reflection surface 23a is located at the lens optical axis position.

  The reflection surface 24a of the finder reflection mirror 24 is inclined with respect to the lens optical axis, and reflects the subject light beam toward the screen 27 of the finder optical system disposed above the lens optical axis. To do.

  The balance weight 33 is a weight fixed to the outside of the opening 22 a located on the opposite side of the sensor reflection mirror 23 and the finder reflection mirror 24. The balance weight 33 is a counterweight for removing the unbalance of centrifugal force caused by the weight of the sensor reflection mirror 23 and the finder reflection mirror 24 when the rotating plate 22 rotates.

  The control unit 32 controls the drive motor 31 to control the rotation of the rotating plate 22, and the optical finder observation state by the finder optical system and the distance measurement by the AF sensor unit 30 in a state synchronized with the rotation of the rotating plate. Switching control is performed between the state and the exposure state in which the subject luminous flux is transmitted through the opening 22a and the image sensor 26 is exposed. Further, during the exposure operation, shutter opening / closing control is performed in synchronization with the rotation of the rotating plate, and the image sensor 26 is driven to capture the imaging signal of the subject image by the subject luminous flux and perform imaging processing.

  When the single-lens reflex camera 20 having the above-described configuration is used to take a single image of a subject image, first, the rotating plate 22 is rotated when the power is turned on, and the finder reflecting mirror 24 is turned into lens light as shown in FIG. Position on the axis. In this state, the subject luminous flux is reflected to the screen 27 side, and optical finder observation is possible through the pentaprism 28 and the eyepiece lens 29.

  The drive motor 31 is driven by the first-stage operation of the release button, the rotating plate 22 rotates, and the sensor reflection mirror 23 is positioned on the lens optical axis as shown in FIG. The subject luminous flux is reflected toward the sensor AF sensor unit 30, and a ranging signal indicating the focus state of the subject image is detected. The distance measurement signal is output to the control unit 32. The taking lens 21 is focused based on the distance measurement signal.

  Subsequently, the rotary plate 22 is further rotated by the second stage operation of the release button, and the opening 22a is positioned on the lens optical axis as shown in FIG. In this state, the shutter 25 is controlled to open and close, and the subject light flux is imaged on the light receiving surface of the image sensor 26 to expose the image sensor 26. The imaging signal of the subject image is taken into the control unit 32 and imaging processing is executed.

  When continuous shooting is performed with the single-lens reflex camera 20, the rotating plate 22 is intermittently driven in accordance with the continuous shooting speed (frame / second). During the rotation, when the finder reflection mirror 24 is on the optical axis of the lens, or during the entire rotation period, the finder can be observed in a flickering state. Further, when the sensor reflection mirror 23 is located on the lens optical axis, the AF sensor unit 30 performs distance measurement. When the opening 22a is positioned on the lens optical axis, the image sensor is exposed. In this way, the operation of the image sensor is synchronized with the rotation of the rotating plate 22, and the subject luminous flux is effectively time-divided and utilized. During the exposure, it is not necessary to stop the rotating plate 22 as long as the opening 22a is on the lens optical axis.

  As described above, the rotating plate 22 is rotationally driven during the camera operation. The rotating plate 22 is provided with a balance weight 33 so as to balance the centrifugal force generated by the reflection mirrors 23 and 24. Therefore, the occurrence of vibration due to the rotation of the rotating plate 22 is suppressed, and a quiet operation state can be obtained.

  According to the single-lens reflex camera 20 of this embodiment described above, instead of the oscillating movable mirror 102 applied in the conventional single-lens reflex camera 100 shown in FIG. Therefore, the rotating plate 22 can be accommodated in a narrow space in the optical path of the subject light flux. Further, since the rotating plate 22 is driven to rotate, there is no bounce phenomenon of the reflecting mirrors 23 and 24 when stopped, and distance measurement and finder observation can be started quickly.

  At the time of continuous shooting, it is not necessary to swing the movable mirror like the conventional single-lens reflex camera 100 described above, it is only necessary to rotationally drive the rotating plate 2, the bounce phenomenon of the reflecting mirror does not occur, and high speed. For example, continuous shooting at 10 frames / second or more becomes possible.

  Note that the AF sensor unit 30 serving as a detector incorporates a luminance sensor unit that detects the luminance of the subject luminous flux instead of the AF distance sensor unit, detects the subject luminance by the sensor unit, and controls the opening and closing of the shutter 25 and imaging. You may comprise so that the exposure control of the element 26 may be performed.

Next, a modified example of the rotating plate 22 applied to the single-lens reflex camera 20 of the second embodiment will be described.
FIG. 11 is a front view of the rotating plate 22A of the modified example. 12A is a cross-sectional view taken along the line AA in FIG. 11, and FIG. 12B is a cross-sectional view taken along the line BB in FIG.

  The rotating plate 22A of the present modification is provided with an opening 22a, a sensor reflecting mirror 23A, and a finder reflecting mirror 24A, as in the rotating plate 22 in the above embodiment. An inclined surface portion 23Aa, which is a structure having inclined surfaces at both ends in the rotational direction, is attached ((B) in FIG. 12). Similarly, both end portions in the rotational direction of the finder reflecting mirror 24A also have inclined surfaces. An inclined surface portion 24Aa, which is a structure, is attached (FIG. 12A).

  By applying the rotating plate 22A of this modification, the air resistance due to the rotation of the rotating plate 22A is reduced by the inclined surface portion, and the load of the drive motor 31 is reduced, so that energy saving at the time of photographing with the camera can be realized.

Next, the single-lens reflex camera which is an imaging device of 3rd embodiment of this invention is demonstrated using FIGS.
13 and 14 are cross-sectional views in each operation state along the optical axis of the single-lens reflex camera of this embodiment. FIG. 13 shows a viewfinder observation state, and FIG. 14 shows a photometry state and an exposure state. Show. FIG. 15 is a front view of a rotating plate applied to the single-lens reflex camera.

  The single-lens reflex camera 40 of this embodiment includes a photographic lens 41 that can be attached to and detached from the camera body as shown in FIGS. 13 and 14, and a lens optical axis in order from the subject side behind the photographic lens 41 as a member built in the camera body. Finder optics described below including a rotating plate 42 as a plate-like rotating body and an image pickup device 43 made of, for example, a CCD and the like, and arranged above the lens optical axis and including a photometric sensor The system, the drive motor 47, and the control part 48 as an adjustment part are comprised.

  The photographic lens 41 is an optical system that takes in a subject luminous flux and forms an image of the subject on the light receiving surface 43 a of the image sensor 43.

  The finder optical system includes a screen 44 disposed above the lens optical axis, a pentaprism 45 disposed on the screen 44, an eyepiece 46 disposed behind the pentaprism 45, and subject luminance. It comprises a photometric sensor 49 for detection.

  The rotating plate 42 has a circular main plane (main surface) intersecting with the lens optical axis, and is rotatably supported by a rotating shaft 47a inclined with respect to the lens optical axis below the lens optical axis. Yes. The rotating plate 42 is rotationally driven through a rotating shaft 47a by a driving motor 47 made of a stepping motor. An opening 42a is formed in the inclined main plane of the rotating plate 2, and a region other than the opening 42a is a reflecting surface 42b.

  The shape of the opening 42a is a fan-shaped opening in which the opening angle between the edge lines 42a1 and 42a2 in the rotation direction is an angle of 180 ° centering on the rotation axis, and the size of this opening is on the optical path of the subject luminous flux. The opening is in a state where it is larger than the image sensor light receiving corresponding surface Ar which is the light receiving corresponding surface corresponding to the light receiving surface 43a of the image sensor 43 at the inclined rotating plate position and does not kick the subject light flux.

  The reflecting surface 42b of the rotating plate 42 forms a reflecting surface that reflects the subject light beam toward the upper screen 44 side.

  The controller 48 controls the drive motor 47 to control the rotation of the rotating plate 42, and the optical viewfinder observation state (including subject luminance metering operation) by the finder optical system in a state synchronized with the rotation of the rotating plate. And an exposure state in which the image sensor 43 is exposed. In the exposure state, the rotation speed of the rotating plate 42 is controlled in accordance with a preset exposure amount setting value so that proper exposure is performed. In addition, an imaging signal of the subject image by the subject luminous flux is captured from the imaging element 43, and imaging processing is performed. Further, the focus state of the photographic lens 41 is detected based on the imaging output of the image sensor 43, and the focus control of the photographic lens 41 is performed.

  When the single-lens reflex camera 40 having the above-described configuration is used to take a single image of a subject image, each operation is performed under the control of the control unit 48. First, the rotating plate 42 is rotated when the power is turned on. As shown in FIG. 13, the reflecting surface 42b of the rotating plate 42 is positioned on the lens optical axis and stopped. In this state, the subject luminous flux is reflected to the screen 44 side, and finder observation is possible via the pentaprism 45 and the eyepiece 46. In addition, the subject luminance is detected (photometric) via the photometric sensor 49.

  The drive motor 47 is driven by the first-stage operation of the release button, and the rotating plate 42 rotates to position the opening 42a on the lens optical axis as shown in FIG. The imaging signal of the subject image output from the imaging element 43 is taken into the control unit 48, and the photographing lens 41 is focused (by imager distance measurement) based on the subject image. After focusing, the rotating plate 42 is driven to rotate and temporarily moves the reflecting surface 42b onto the lens optical axis and stops.

  Subsequently, the rotary plate 42 is driven to rotate by the second-stage operation of the release button, the opening 42a is moved toward the lens optical axis position (FIG. 12), and the subject luminous flux is connected to the light receiving surface 43a of the image sensor 43. The exposure of the image sensor 43 is started. At the time of exposure, the required rotation speed of the rotating plate 2 is calculated from the subject luminance data detected by the photometric sensor 49 in order to perform exposure according to a preset exposure amount setting value, and according to the rotation speed. The opening 42a crosses the lens optical axis. Thereby, exposure of the image sensor 43 according to the exposure amount setting value is executed. The imaging signal of the subject image is captured by the control unit 48 and imaging processing is executed.

  When continuous shooting is performed with the single-lens reflex camera 40, the rotating plate 42 is intermittently driven in accordance with the continuous shooting speed (frame / second). During the rotation, when the reflecting surface 42b is on the lens optical axis, or during the entire rotation period, the finder can be observed intermittently, and photometry is also performed at the same time. Further, when the lens is positioned on the optical axis of the opening 42a, distance measurement is performed by the image sensor, and focusing of the photographing lens is also performed. After the distance measurement, the image sensor 43 is exposed during a period in which the opening 42a moves toward the lens optical axis. In this case as well, the necessary rotation speed of the rotating plate 42 for performing exposure according to the exposure amount setting value is calculated in the same manner as in the single shooting described above, and the opening 42a crosses the lens optical axis according to the rotation speed. . Thereby, exposure of the image sensor 43 according to the exposure amount setting value is repeatedly executed.

  According to the single-lens reflex camera 40 of the present embodiment described above, the inclined single-lens reflex camera having the opening 42a and the reflecting surface 42b is used instead of the oscillating movable mirror 102 applied in the conventional single-lens reflex camera 100 shown in FIG. Since the rotating plate 42 is employed, the rotating plate 42 can be accommodated in a narrow space in the optical path of the subject light flux. Further, since the rotating plate 42 is driven to rotate, there is no bounce phenomenon when stopped, and distance measurement, finder observation, and photometry can be started quickly. Further, the rotation speed of the rotating plate 42 can be set according to the exposure amount setting value, and appropriate exposure can be performed, and there is no need to provide the shutter 103 unlike the conventional single-lens reflex camera 100. Further, there is no need to provide an AF sensor unit, and the configuration is simple.

  Further, at the time of continuous shooting, it is not necessary to swing the movable mirror like the conventional single-lens reflex camera 100 described above, it is only necessary to rotationally drive the rotating plate 42, there is no reflection surface bound phenomenon, and high speed. Continuous shooting, for example, continuous shooting at 10 frames / second or more becomes possible.

  A rotating plate 42A shown in FIG. 16 can be proposed as a modification of the rotating plate 42 of the single-lens reflex camera 40 of the third embodiment described above. The rotating plate 42A is a fan-shaped opening with an opening 42Aa having edge angles 42Aa1 and 42Aa2 in the rotation direction and an opening angle of 180 ° or less about the rotation axis. The aperture is a state where the image pickup element light receiving surface equivalent area Ar corresponding to the light receiving surface 43a of the image pickup element 43 is larger at the inclined rotation plate position on the optical path and does not kick the subject light flux.

  A rotating plate 42B shown in FIG. 17 can be proposed as another modification of the rotating plate 42 of the single-lens reflex camera 40 of the third embodiment. The rotating plate 42B has not a fan-shaped opening but a notch in which the opening angle of the notch edge lines 42Ba1 and 42Ba2 in the rotation direction is an angle of 180 ° with the rotation axis as the center.

  Further, a rotating plate 42C shown in FIG. 18 can be proposed as still another modification example of the rotating plate 42 of the single-lens reflex camera 40 of the third embodiment. In the rotating plate 42C, three fan-shaped RGB filters 42Ca, 42Cb, and 42Cc are arranged in a fan-shaped opening. Each of these RGB filters 42Ca, 42Cb, 42Cc is larger than the image sensor light receiving surface equivalent area Ar. When the rotating plate 42C of this modification is applied, color imaging can be performed using a monochrome type as an image sensor.

  Further, a rotating plate 42D shown in FIG. 19 can be proposed as still another modified example of the rotating plate 42 of the single-lens reflex camera 40 of the third embodiment. The rotating plate 42D is provided with the optical filter 42Da in the fan-shaped opening, and it is not necessary to provide an optical filter on the image sensor side.

  Further, a rotating plate 42E shown in FIG. 20 can be proposed as still another modification example of the rotating plate 42 of the single-lens reflex camera 40 of the third embodiment. The rotating plate 42E is provided with a plurality of openings 42Ea, 42Eb, 42Ec, 42Ed in the rotational direction. Each opening is larger than the image sensor light receiving surface equivalent area Ar. When the rotating plate 42E of this modification is applied, it is possible to slow down the rotating speed of the rotating plate 42E during continuous shooting, and further high-speed continuous shooting is possible.

  In addition, the rotating plate of each modified example described above can be applied as the rotating plate of the single-lens reflex cameras 10 and 20 of the first and second embodiments described above.

  The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention at the stage of implementation. Further, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements.

  According to the image pickup apparatus of the present invention, an image pickup apparatus using an image pickup element has a simpler configuration and has a quick response to switching between an exposure state and a non-exposure state of the image pickup element, for example, high-speed continuous shooting. It can be used as an imaging device that can be made compact.

It is sectional drawing along the optical axis which shows the main structures of the single-lens reflex camera which is an imaging device of 1st embodiment of this invention, Comprising: AF ranging state is shown. It is sectional drawing along the optical axis which shows the main structures of the single-lens reflex camera which is an imaging device of 1st embodiment of this invention, Comprising: An exposure state is shown. It is a front view of the rotating plate applied to the single-lens reflex camera of FIG. It is a front view of the rotating plate of the 1st modification with respect to the rotating plate applied to the single-lens reflex camera of FIG. It is a front view of the rotating plate of the 2nd modification with respect to the rotating plate applied to the single-lens reflex camera of FIG. 1, Comprising: The exposure start state is shown. FIG. 6 is a front view of the rotating plate of FIG. 5 and shows an exposure end state. It is sectional drawing along the optical axis which shows the main structures of the single-lens reflex camera which is an imaging device of 2nd embodiment of this invention, Comprising: An optical finder observation state is shown. FIG. 8 is a cross-sectional view along the optical axis showing the main configuration of the single-lens reflex camera in FIG. 7, showing an AF distance measurement state. FIG. 8 is a cross-sectional view along the optical axis showing the main configuration of the single-lens reflex camera in FIG. It is a front view of the rotating plate applied to the single-lens reflex camera of FIG. FIG. 8 is a front view of a rotating plate of a modified example of the rotating plate applied to the single-lens reflex camera of FIG. 7. FIG. 12A is a cross-sectional view taken along the line AA in FIG. 11 and FIG. 12B is a cross-sectional view taken along the line BB in FIG. 11. It is sectional drawing along the optical axis of the single-lens reflex camera of 3rd embodiment of this invention, Comprising: A finder observation state is shown. It is sectional drawing along the optical axis of the single-lens reflex camera of FIG. 13, Comprising: A photometry state and an exposure state are shown. It is a front view of the rotating plate applied to the single-lens reflex camera of FIG. It is a front view of the rotary plate of the modification with respect to the rotary plate of the single-lens reflex camera of FIG. It is a front view of the rotating plate of another modification with respect to the rotating plate of the single-lens reflex camera of FIG. FIG. 14 is a front view of a rotating plate of still another modified example with respect to the rotating plate of the single-lens reflex camera of FIG. 13. FIG. 14 is a front view of a rotating plate of still another modified example with respect to the rotating plate of the single-lens reflex camera of FIG. 13. FIG. 14 is a front view of a rotating plate of still another modified example with respect to the rotating plate of the single-lens reflex camera of FIG. 13. It is sectional drawing along the optical axis which shows the main structures of the single-lens reflex camera which is a conventional imaging device.

Explanation of symbols

1, 21, 41 ... Photography lens (optical system)
2, 2A, 2B, 22, 22A, 42A, 42B,
42C, 42D, 42E
... Rotating plate (plate-like rotating plate)
2a, 2Aa, 2Ba, 22a, 22Aa,
42a, 42Aa
... Opening (first area)
2a1, 2a2, 2Aa1, 2Aa2, 2Ba1, 2Ba2,
22a1, 22a2
... Side edge of opening (side edge of first region)
3, 23, 23A
... Reflection mirror for sensors (second area)
4, 25 ... Shutter 5, 26, 43 ... Image sensor 6, 30 ... AF sensor (detector)
7, 31, 47 ... Drive motor (stepping motor)
7a, 31a ... Rotating shaft 8, 32, 48 ... Control part 23Aa, 24Aa ... Inclined surface part (structure)
24, 24A
... Reflector mirror for viewfinder (third area)
27, 44
... Screen (finder optics)
28, 45
... Pental prism (finder optical system)
29,46
... Eyepiece lenses (finder optics)
Ar ... Image sensor light receiving surface equivalent area (light receiving compatible surface)

Claims (18)

An image sensor;
An optical system for causing a subject luminous flux to enter the light receiving surface of the image sensor and generating a subject image;
A detector for detecting optical characteristics of the subject luminous flux;
The first region that has a first region that transmits the subject light beam and a second region that reflects the subject light beam and enters the detector, and rotates on a plane that intersects the optical axis of the light beam. A plate-like rotating body that generates a state corresponding to each of the above-mentioned regions and the second region;
An imaging apparatus comprising:   The imaging apparatus according to claim 1, wherein the plate-like rotating body rotates about an axis parallel to the optical axis.   The imaging apparatus according to claim 1, wherein the plate-like rotator rotates around an axis having a constant inclination of less than 90 degrees with respect to the optical axis.   The imaging apparatus according to claim 1, further comprising a finder optical system, wherein the plate-like rotator has a third region that guides the subject light beam to the finder optical system.   The imaging apparatus according to claim 1, wherein the detector detects an in-focus state of the image of the subject light beam.   The imaging device according to claim 1, wherein the detector performs luminance detection or focus state detection of the subject light flux.   The plate-like rotator has the first region on a plane including the light receiving surface such that a region where the subject image is formed by the subject light flux is larger than a light receiving corresponding surface corresponding to the light receiving surface. The imaging apparatus according to claim 1, wherein the shape is formed.   The plate-shaped rotating body has a shape corresponding to the shape of the side edge portion of the light receiving correspondence surface corresponding to the light receiving surface in which the side edge portion of the first region is opposed on a straight line passing through its own rotation axis. The imaging apparatus according to claim 1, wherein:   The plate-like rotating body has a shape corresponding to the shape of the side edge portion of the light-receiving corresponding surface corresponding to the light-receiving surface, at least one of the side edges of the first region facing in the direction around its own rotation axis. The imaging apparatus according to claim 1, wherein the imaging apparatus is provided.   The plate-like rotator is characterized in that the side edges of the first region facing each other on a straight line passing through the rotation axis thereof have a shape corresponding to a concentric circle centered on the rotation axis. Item 2. The imaging device according to Item 1.   The plate-shaped rotating body is characterized in that side edges of the first region facing each other in a direction around its rotation axis are positioned on two different straight lines passing through the rotation axis. The imaging apparatus according to 1.   The imaging apparatus according to claim 1, further comprising a control unit that synchronizes the rotation of the plate-like rotating body and the imaging operation of the subject image by the imaging element. And a shutter;
A control unit that synchronizes the rotation of the plate-like rotating body and the operation of the shirter;
The imaging apparatus according to claim 1, further comprising:   The imaging apparatus according to claim 1, wherein the plate-like rotating body is rotated by a stepping motor.   The imaging apparatus according to claim 1, wherein the plate-like rotator is provided with a balance weight for balancing its own weight.   The imaging apparatus according to claim 1, wherein the plate-like rotator has a structure that reduces air resistance due to rotation in the vicinity of the second region.   The imaging apparatus according to claim 4, wherein the plate-like rotating body is formed with a structure that reduces air resistance due to rotation in the vicinity of the third region. An image sensor;
An optical system for generating a subject image related to a subject light beam incident on a light receiving surface of the image sensor;
A detector for detecting optical characteristics of the image by the subject luminous flux;
A plate-shaped first region that transmits the subject image and a second region that reflects the subject image and enters the detector, and an axis orthogonal to the principal surface of the plate A plate-like rotating body that generates a state corresponding to each of the first region and the second region by rotating about the center;
An imaging apparatus comprising:

Images