JP5040530B2 - Imaging system, interchangeable lens and camera body - Google Patents

Description

  The present invention relates to posture detection of an image pickup apparatus, and more particularly to posture detection in an interchangeable lens image pickup apparatus having a camera shake correction function.

  In recent years, the progress of digitization has been remarkable also in an interchangeable lens imaging apparatus. In the interchangeable lens imaging device, it is possible to photograph a work that faithfully reflects the photographer's intention by selecting and using a lens according to the purpose and situation of the photographing.

  Further, in general imaging apparatuses, a camera shake correction function for correcting a camera shake of a photographer has been put into practical use. In the camera shake correction function, the camera shake correction lens in the optical system is moved in the plane perpendicular to the optical axis in the direction to cancel the camera shake of the photographer by an amount that cancels the camera shake. There is a so-called lens shift system that realizes a blur correction function.

Patent Document 1 discloses an “image blur prevention system having a blur detection sensor in a camera body and a blur correction mechanism in an interchangeable lens”. “A system capable of preventing vibration in any type of camera / lens combination by appropriately integrating the camera shake signal from the camera shake detection sensor in the camera or in the lens” is obtained.
JP 7-191355 A

  However, the “control device for preventing image blur” disclosed in Patent Document 1 realizes a “system capable of image stabilization in any type of camera / lens combination”. I can't get information.

  An object of the present invention is to provide a lens-interchangeable image pickup apparatus having a camera shake correction function, which can obtain posture information of the image pickup apparatus without a separate posture detection sensor. .

In order to solve the above problems, an imaging system of the present invention is an imaging system including an interchangeable lens and a camera body, and the interchangeable lens includes a posture determination unit that determines a posture of the imaging system, and the posture A first communication unit that transmits posture information of the imaging system determined by the determination unit to the camera body, and the posture determination unit is a shake detection unit that detects vibration of the imaging system, The posture information is vibration information of the imaging system,
The camera body includes a second communication unit that receives posture information of the imaging system transmitted from the first communication unit. With this configuration, it is possible to know the attitude of the imaging system without separately providing an attitude detection sensor.

  Since the imaging system of the present invention performs posture determination by receiving posture information or vibration information from the interchangeable lens, it is possible to know the posture of the imaging system without providing a posture detection sensor separately. In addition, by writing the orientation of the imaging system in the header of the image file, it is always possible to play back in an appropriate orientation, whether it is an image file shot in an upright position or an image file shot in a vertical orientation. Can be displayed.

Embodiments of an interchangeable lens imaging apparatus having a camera shake correction function according to the present invention will be described below with reference to FIGS.
(1. Configuration)
1 and 2 are configuration diagrams of an interchangeable lens type imaging apparatus having a camera shake correction function according to the present invention.
(1-1. Camera body)
(1) is a camera body. The camera body (1) includes a sequence microcomputer (100) for controlling the sequence, digital image processing, and digital processing for controlling the mechanical control unit (103) for controlling the mirror groups (108, 109) and the shutter (107). Microcomputer (101), external memory unit (102) that is an interface with a recording medium, focus detection unit (104) that performs focus detection, image display liquid crystal unit (105) that displays an image after shooting and various information, imaging An image sensor driving unit (113) for driving and controlling the sensor (106), an image sensor (106) such as a CCD, a shutter (107), a sub mirror (108) for guiding light to the focus detection unit (104), a focusing screen ( 110) main mirror (109) for guiding light to the main, The lens (109) is a semi-transmissive mirror, a focusing screen (110) that forms an image from the interchangeable lens (2), and a pentaprism that uses an image formed on the focusing screen (110) as an erect image. (111) and an eyepiece (112) are incorporated.
(1-2. Interchangeable lens)
(2) is an interchangeable lens that can be attached to and detached from the camera body (1). In the interchangeable lens (2), a lens microcomputer (200) that controls various units and incorporates various lens information, blur amount detection A blur detection unit (201) for controlling the blur, a blur correction unit (202) for controlling the blur correction lens unit (207), a focus control unit (203) for controlling the focus lens (205), and an aperture for controlling the diaphragm unit (206). A control unit (204) is incorporated.
(2. Operation)
Light from the subject passes through the interchangeable lens (2), is bent upward by the main mirror (109), and forms an image on the focusing screen (110). The photographer can observe the image through a pentaprism (111) and an eyepiece lens (112). A part of light from the subject is transmitted through the main mirror (109), bent downward by the sub mirror (108), and guided to the focus detection unit (104). The focus detection unit (104) may be of a method generally called a phase difference detection method.

  When a release button (not shown) is pressed halfway, power is supplied to each microcomputer and each unit by a switch (S1) (see FIG. 2) that is turned on. The sequence microcomputer (100) in the camera body (1) activated by the power supply is connected to the electric section (not shown) of the mount (see FIG. 2) from the lens microcomputer (200) in the interchangeable lens (2) similarly activated by the power supply. Various lens data are received through the memory and stored in the built-in memory. Next, when it is determined that the interchangeable lens (2) has a camera shake correction function, the lens microcomputer (200) is instructed to operate the camera shake detection unit (201), and the camera shake correction unit (202) is also operated. Instruct them to do so.

  Next, the sequence microcomputer (100) acquires a defocus amount (hereinafter referred to as Df amount) from the focus detection unit (104), and drives the focus lens (205) by the Df amount so as to drive the lens microcomputer (200). The lens microcomputer (200) controls the focus control unit (203) to operate the focus lens (205) by the amount of Df. As described above, when the focus detection and the driving of the focus lens (205) are repeated, the Df amount becomes small, and when it becomes less than a predetermined amount, it is determined that the focus is achieved, and the driving of the focus lens (205) is stopped.

  After that, the sequence microcomputer (100) waits for the switch (S2) (see FIG. 2) to be turned on when the release button (not shown) is fully pressed, and when it is turned on, the sequence microcomputer (100) The microcomputer (200) is instructed to set the aperture value calculated based on the output from the photometric sensor (not shown), and the lens microcomputer (200) controls the aperture drive unit (204) to the indicated aperture value. The aperture unit (206) is narrowed down.

  Simultaneously with the aperture value instruction, the sequence microcomputer (101) gives a release sequence operation instruction to the digital processing microcomputer (101), and the digital processing microcomputer (101) first uses the mechanical control unit (103) to provide mirrors ( 109, 108) is withdrawn from the optical path. After the evacuation is completed, the digital processing microcomputer (101) instructs the image sensor driving unit (113) to drive the image sensor (106), and instructs the mechanical control unit (103) to operate the shutter (107). The mechanical control unit (103) exposes the image sensor (106) for the time of the shutter speed calculated based on the output from a photometric sensor (not shown).

  After the exposure is completed, the digital processing microcomputer (101) reads the image data from the image sensor (106) via the image sensor driving unit (113), and after the predetermined image processing, the captured image is displayed on the image display liquid crystal unit (105). Is displayed, and image data is written to the storage medium via the external memory unit (102). Further, after the exposure is completed, the mechanical control unit (103) is instructed to reset the mirrors (109, 108) and the shutter (107) to the initial positions at the same time, and the completion of the exposure is notified to the sequence microcomputer (100). The sequence microcomputer (100) instructs the lens microcomputer (200) to return the lens position of the blur correction lens unit (207) to the initial position and resets the aperture unit (206) to the open position. (200) issues a reset command to each unit. After the reset is completed, the lens microcomputer (200) notifies the sequence microcomputer (100) of the completion of the reset.

The sequence microcomputer (100) waits for reset completion information from the lens microcomputer (200) and completion of a series of processes after exposure of the digital processing microcomputer (101), and then the state of the release button (not shown) is pressed. (Since both switches (S1, S2) (see FIG. 2) are OFF), the photographing sequence is terminated.
(3. Shake correction essential part)
(3-1. Block diagram)
FIG. 3 is a configuration diagram showing a main part of the blur correction of the interchangeable lens (2) having the camera shake correction function according to the present invention.

  The blur correction lens unit (207) includes a correction lens group (210), an image blur correction drive mechanism (212) having a yawing actuator (212X) and a pitching actuator (212Y), a light emitting element (211A), and a light receiving element (211B). The position detecting means (211) for detecting the position of the correction lens group (210) is provided.

  The blur correction unit (202) that controls the blur correction lens unit (207) includes a correction drive control means (213) and an attitude detection means (214).

  The correction lens group (210) is a correction lens group of the imaging optical system of the interchangeable lens (2), and moves in two directions X and Y orthogonal to each other in a plane perpendicular to the optical axis (Z), thereby The axis (Z) is decentered to play a role in correcting image movement.

  The position detection means (211) is a means for detecting the position of the correction lens group (210) by the light emitting element (211A) and the light receiving element (211B) shown in FIG. 3, and includes a yawing drive control unit (213X) and a pitching purpose. A feedback control loop for driving and controlling the correction lens group (210) is formed together with the drive control unit (213Y).

  The yawing drive control unit (213X) and the pitching drive control unit (213Y) are arranged via the image blur correction drive mechanism (212) having the yawing actuator (212X) and the pitching actuator (212Y) via the correction lens group (210). ) Is driven and controlled in two directions X and Y that are orthogonal to each other in a plane perpendicular to the optical axis (Z) of the interchangeable lens (2). Here, the yawing direction in the camera body (1) is referred to as the X direction, and the pitching direction is referred to as the Y direction.

  The yawing drive control unit (213X) and the pitching drive control unit (213Y) transmit the control signal from the lens microcomputer (200) to the light of the interchangeable lens (2) via the D / A conversion units (213A, 213B). A correction drive control means (213) for correcting the axis (Z) is configured.

  The angular velocity sensors (220X, 220Y) are for detecting the movement of the camera body (1) itself including the interchangeable lens (2). Based on the output when the camera body (1) is stationary, Outputs both positive and negative angular velocity signals depending on the direction of movement of the camera body (1), and two angular velocity sensors (220X, 220Y) are provided to detect movement in two directions, the yawing direction and the pitching direction, respectively. ing. Thus, the angular velocity sensors (220X, 220Y) constitute a shake detection unit (201) that detects the movement of the camera body (1) due to camera shake and other vibrations.

In this blur detection unit (201), the output signal output from the angular velocity sensor (220X, 220Y) is a DC drift component in the unnecessary band component included in the output signal by the high-pass filter (HPF) (221X, 221Y). Further, the resonance frequency components and noise components of the angular velocity sensors (220X, 220Y) in the unnecessary band components included in the output signal are removed by the low-pass filter (LPF) (222X, 222Y). After the level of the output signal is adjusted by the amplifier (223X, 223Y), the analog output signal output from the amplifier (223X, 223Y) by the A / D converter (224X, 224Y) is converted into a digital signal. The digital output signal is input to the lens microcomputer (200).
(3-2. Perspective view)
Here, with reference to the exploded perspective view of FIG. 4, the image blur correction drive mechanism (212) for driving and controlling the correction lens group (210) in the interchangeable lens (2) will be described.

  The fixed frame (301) holds the yawing movement frame (302) so as to be slidable in the yawing direction via the yawing shafts (302A, 302B), and the yawing movement frame (302) has two pitching portions. A pitching movement frame (303) is slidably held in the pitching direction via the shafts (303A, 303B), and the correction lens group (210) is fixed to the pitching movement frame (303).

  The coils (304X, 304Y) are fixed to the pitching movement frame (303). On the other hand, the fixed frame (301) holds a magnet (305X) and a yoke (306X) corresponding to the coil (304X), and drives the correction lens group (210) in the pitching direction via the pitching moving frame (303). A pitching actuator to be controlled (an actuator composed of a coil and a magnet) (212Y) is configured. Similarly, the fixed frame (301) holds the magnet (305Y) and the yoke (306Y) corresponding to the coil (304Y), and drives the correction lens group (210) in the yawing direction via the pitching movement frame (303). A yawing actuator (an actuator made up of a coil and a magnet) (212X) is configured.

  Further, the light emitting element (211A) constituting the position detecting means (211) is fixed to the pitching movement frame (303), and the light receiving element (211B) fixed to the fixed frame (301) is the light emitting element (211A). The projection light is received, and the two-dimensional position coordinates of the correction lens group (210) are detected.

  The yawing current value detector (214X) shown in FIG. 3 detects the current value flowing through the coil (304X) when the yawing actuator (212X) is operated, and similarly, the pitching current value detector (214Y). Detects the value of the current flowing through the coil (304Y) when the pitching actuator (212Y) is operated, and constitutes a posture detecting means (214) for detecting the posture of the camera body (1).

  The lens microcomputer (200) shown in FIG. 3 includes a camera body (1) posture (an upright posture or a vertical posture) based on detection values of the yawing current value detection unit (214X) and the pitching current value detection unit (214Y). A non-volatile memory (for example, an EEPROM) storing a control signal for image blur correction characteristics necessary for drive control of the correction lens group (210) required for motion correction, and a posture determination unit (217) for determining (orientation / posture) And a motion determination unit (218) for determining a shooting operation of the camera body (1) based on a detection signal of the motion detection unit (201), obtaining a motion direction and acceleration, and a posture A gain that adjusts the gain of the correction operation corresponding to the blur correction characteristic from the output signals of the determination unit (217), the blur correction characteristic storage unit (216), and the motion determination unit (218). An adjustment unit (215) is provided.

  The operation determination unit (218) performs filtering, integration processing, phase compensation, gain adjustment, clipping on the output signals of the angular velocity sensors (220X, 220Y) captured via the A / D conversion means (224X, 224Y). Processing or the like is performed to determine the photographing operation of the camera body (1). The gain adjustment unit (215) determines the drive direction of the shake correction operation from the posture of the camera body (1) determined by the posture determination unit (217) and selects the output side of the control signal. Based on the data output from the blur correction characteristic storage unit (216), the drive control amount of the correction lens group (210) required for blur correction is obtained from the signal output from 218). For example, in the case of the upright posture shown in FIG. 5A, the control signals for the panning operation and the vertical camera shake operation are sent to the yawing drive control unit (213X) side, and the tilting operation and the horizontal camera shake operation are performed. The control signal is output to the pitching drive controller (213Y). On the other hand, in the case of the vertical posture shown in FIG. 5B, control signals for the panning operation and the horizontal camera shake operation are sent to the pitching drive control unit (213Y) side, and the tilting operation and the vertical camera shake operation are performed. An operation control signal is output to the drive control unit for yawing (213X). Further, the control signal from the gain adjustment unit (215) is sent to the yawing drive control unit (213X) and the pitching drive control via the D / A conversion units (213A, 213B) constituting the correction drive control means (213). To the yaw actuator (212X) and the pitching actuator (212Y) from the yawing drive controller (213X) and the pitching drive controller (213Y), and the correction lens group (210). Is driven to correct the movement of the image.

Current value detection and posture determination by the yawing current value detection unit (212X) and the pitching current value detection unit (212Y) in the posture determination unit (217) will be described. In photographing in a normal upright posture as shown in FIG. 5A, the posture of the pitching movement frame 303 is as shown in FIG. At this time, in order to hold the correction lens group (210) at the center of the optical axis (Z) in the Y direction, the weights of the correction lens group (210), the pitching moving frame (303), and the coils (304X, 304Y) are increased. Since it is applied in the direction of gravity (Y direction), it is necessary to pass a current to lift the weight of the coil (304Y). The current value at that time is Iy1 shown in FIG. Regarding the X direction, it is not necessary to consider the weight of the correction lens group (210) for holding the center of the optical axis (Z), but it is necessary to consider the weight of the yawing movement frame (302). The value of current flowing through the coil (304X) is smaller than Iy1, but becomes Ix2. Conversely, in the vertical orientation rotated 90 ° about the optical axis (Z) as shown in FIG. 5B, the posture of the pitching movement frame 303 is as shown in FIG. 6B. At this time, in order to hold the correction lens group (210) at the center of the optical axis (Z) in the X direction, in addition to the correction lens group (210), the pitching moving frame (303), and the coils (304X, 304Y), yawing Since the weight of the moving frame (302) is applied in the direction of gravity (X direction), it is necessary to pass a current for lifting the weight of the moving frame (302X) to the coil (304X). The current value at that time is Ix1 which is larger than Iy1. Regarding the Y direction, it is not necessary to consider the weight of the correction lens group (210) at the center of the optical axis (Z), but it is necessary to consider only the weight of the pitching moving frame (303). The value of the current passed through (304Y) is Iy2, which is smaller than Ix2. Thus, since the drive current value flowing through the coils (304X, 304Y) is determined by the posture of the camera body (1) to be photographed, the camera body is detected by the posture determination unit (217) by detecting this current value. It becomes possible to determine the posture of (1).
(4. First embodiment)
First, the procedure performed by the lens microcomputer (200) will be described with reference to the flowchart of FIG. First, in step 1 (S1), the posture determination unit (214) captures the current value Ix from the yawing current value detection unit (214X) and the current value Iy from the pitching current value detection unit (214Y) into the lens microcomputer (200). . In step 2 (S2), the lens microcomputer (200) determines the posture of the camera body (1). For example, when the current value flowing through the coil (304X) is Ix2 and the current value flowing through the coil (304Y) is Iy1, it can be seen that the camera body (1) is in the upright posture of FIG. Conversely, when the current value flowing through the coil (304X) is Ix1 and the current value flowing through the coil (304Y) is Iy2, it can be seen that the camera body (1) is in the vertical orientation of FIG. In step 3 (S3), a camera posture flag (FLG1) is set based on the posture information of the camera body (1) determined in step 2 (S2). For example, the camera posture flag (FLG1) is set to 0 when the camera body (1) is in the upright posture, and 1 is set to the camera posture flag (FLG1) when the camera body (1) is in the vertical posture. In step 4 (S4), the posture information obtained in step 3 (S3) is sent from the lens microcomputer (200) via the electrical section (not shown) of the mount to the sequence microcomputer (100) in the camera body (1). Send to.

  Next, regarding the procedure to be processed by the sequence microcomputer (100) in the camera body (1), in step 5 (S5), the interchangeable lens mounted by communicating with the lens microcomputer (200) in the interchangeable lens (2). Check the type of (2). In step 6 (S6), it is determined whether the attached interchangeable lens (2) is an interchangeable lens with built-in camera shake correction. If it is not an interchangeable lens with built-in camera shake correction in step 7 (S7), it is determined that the camera is always in the upright posture state. To do. In step 8 (S8), when it is determined in step 6 (S6) that the lens has camera shake correction, communication between the camera body (1) and the interchangeable lens (2) is performed, and camera posture information is obtained by the camera posture flag (FLG1). . In step 9 (S9), the sequence microcomputer (100) in the camera body (1) can determine the vertical and horizontal posture of the camera body (1) based on the camera posture flag (FLG1).

Here, the lens microcomputer (200) is an example of the posture determination unit and the first communication unit of the present invention. The sequence microcomputer (100) is an example of the second communication unit and the interchangeable lens determination unit of the present invention.
(5. Second embodiment)
As a first embodiment, a method for performing vertical / horizontal determination of the camera body (1) in the interchangeable lens (2) and communicating the determination result from the interchangeable lens (2) to the camera body (1) has been described. An embodiment will be described with reference to the flowchart of FIG. First, a procedure performed by the lens microcomputer (200) will be described.

  First, in step 100 (S100), a request for vertical / horizontal posture information is received from the sequence microcomputer (100) of the camera body (1) by communication between the camera body (1) and the interchangeable lens (2). In step 101 (S101), the current value Ix from the yawing current value detection unit (214X) and the current value Iy from the pitching current value detection unit (214Y) are obtained from the attitude determination unit (214). In step 102 (S102), the current value Ix by the yawing current value detection unit (214X) and the current value Iy by the pitching current value detection unit (214Y) are A / D converted in the lens microcomputer (200). In step 103 (S103), the data of the current values Ix and Iy A / D converted in step 102 (S102) are communicated between the camera body (1) and the interchangeable lens (2) and transmitted to the sequence microcomputer (100). .

  Next, regarding the procedure to be processed by the sequence microcomputer (100) of the camera body (1), first, as step 110 (S110), the exchange that is mounted by communicating with the lens microcomputer (200) in the interchangeable lens (2). Check the type of lens (2). In step 111 (S111), it is determined whether the mounted interchangeable lens (2) is an interchangeable lens with built-in camera shake correction. If it is not an interchangeable lens with built-in camera shake correction in step 112 (S112), it is determined that the camera is always in the upright posture state. To do. In step 113 (S113), when it is determined in step 110 (S110) that the lens has camera shake correction, the camera body (1) and the interchangeable lens (2) communicate with each other, and the posture determination unit (214) detects the yawing current value. The current value Ix by the unit (214X) and the current value Iy by the pitching current value detection unit (214Y) are requested. In step 114 (S114), the posture determination unit (214) determines the current value Ix from the yawing current value detection unit (214X) and the current value Iy from the pitching current value detection unit (214Y) from the camera body (1) and the interchangeable lens ( Receive by communication in 2). In step 115 (S115), the sequence microcomputer (100) determines the posture of the camera body (1). For example, when the current value Ix by the yawing current value detection unit (214X) obtained in step 113 (S113) is Ix2, and the current value flowing through the current value Iy by the pitching current value detection unit (214Y) is Iy1 It can be seen that the camera body (1) is in the upright posture of FIG. Conversely, when the current value Ix by the yawing current value detection unit (214X) is Ix1 and the current value Iy by the pitching current value detection unit (214Y) is Iy2, the camera body (1) is shown in FIG. It can be seen that this is a vertical orientation. In step 116 (S116), the camera body (1) is controlled based on the result of vertical / horizontal determination.

  Here, the posture determination unit (214) is an example of the shake detection unit of the present invention. The current value Ix and the current value Iy are examples of vibration information of the present invention. The lens microcomputer (200) is an example of the first communication unit of the present invention. The sequence microcomputer (100) is an example of the second communication unit and posture determination unit of the present invention.

  As a means for detecting the posture of the camera body (1), the current value of the yawing actuator (212X) and the pitching actuator (212Y) for driving the correction lens group (210) is measured. There is no need to use a dedicated sensor and there is no cost increase.

  In the above embodiment, the current values of both the yawing actuator (212X) and the pitching actuator (212Y) are detected by the yawing current value detection unit (214X) and the pitching current value detection unit (214Y). The posture of the camera body (1) can be specified only by detecting one of the current values. However, by detecting both current values, even if an abnormality occurs in one current value detection unit, it can be determined more accurately.

  In addition, the digital camera body (1) and the interchangeable lens (2) have been described as examples of the image pickup device, but any device equipped with a camera shake correction device may be used, for example, a silver salt film is used. It may be. The shape of the camera body (1) is not limited to that described in the above embodiment.

  Furthermore, in the above embodiment, the image blur correction drive mechanism (212) is configured by an actuator composed of a magnet and a coil, but this is not the only form. Furthermore, the vertical posture shown in FIG. 5B may be a posture obtained by inverting the illustrated posture by 180 degrees.

  The present invention is useful for an interchangeable lens imaging apparatus having a camera shake correction function regardless of a silver salt system or a digital system.

Overall configuration of camera body and interchangeable lens Block diagram of camera body and interchangeable lens Configuration diagram showing main parts of image stabilization Perspective view showing the main part of image stabilization Explanatory drawing showing the shooting posture of the camera Explanatory drawing which shows the attitude | position of a pitching movement frame Graph showing the current value of the actuator Flow chart showing the first embodiment Flow chart showing the second embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Camera body 100 Sequence microcomputer 101 Digital processing microcomputer 102 External memory unit 103 Mechanical control unit 104 Focus detection unit 105 Image display liquid crystal unit 106 Imaging sensor 107 Shutter 108 Submirror 109 Main mirror 110 Focus plate 111 Pentaprism 112 Eyepiece lens 113 Imaging sensor Drive unit 2 Interchangeable lens 200 Lens microcomputer 201 Shake detection unit 202 Shake correction unit 203 Focus control unit 204 Aperture drive unit 205 Focus lens 206 Aperture unit 207 Shake correction lens unit

Claims (4)

An imaging system composed of an interchangeable lens and a camera body,
The interchangeable lens is
An attitude determination unit that determines an attitude of the imaging system;
A first communication unit that transmits posture information of the imaging system determined by the posture determination unit to the camera body;
Have
The posture determination unit is a shake detection unit that detects vibration of the imaging system,
The posture information is vibration information of the imaging system,
The camera body is
A second communication unit that receives posture information of the imaging system transmitted from the first communication unit;
Having
An imaging system characterized by that. It can be used for the imaging system according to claim 1.
An interchangeable lens characterized by that. It can be used for the imaging system according to claim 1.
A camera body characterized by that. Determine whether the attached interchangeable lens has the posture determination unit,
When it is determined that the mounted interchangeable lens does not have the posture determination unit, an interchangeable lens determination unit that sets the posture information of the imaging system as an upright posture,
Further having
The camera body according to claim 3.

Images