JP2007271996A - Lens device and camera system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens device capable of preventing the displacement of a subject image caused by the initializing operation of a vibration-proof unit from being viewed by a photographer through a finder. <P>SOLUTION: The lens device 102 is attachably/detachably attached to a first camera having an optical finder 105 and a second camera 141 having no optical finder. The lens device has the vibration-proof unit having a movable unit 127 capable of moving with respect to a fixed unit for the purpose of vibration-proof operation, and balls 16a to 16b arranged between the movable unit and the fixed unit and capable of moving with the movement of the movable unit. When the lens device is attached to the second camera, a control means controls to perform initializing processing for moving the balls of the vibration-proof unit to a predetermined position in specified timing. When the lens device is attached to the first camera, the control means controls not to perform the initializing processing in the specified timing. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an anti-vibration unit that suppresses image blur, and relates to an interchangeable lens apparatus that includes a so-called ball guide type image stabilization unit.

  A ball guide type vibration isolating unit mounted on an interchangeable lens is proposed in Patent Document 1, for example. Specifically, a plurality of balls are sandwiched between the base member of the vibration isolation unit and the movable unit including the vibration isolation lens using a spring force, and the movable unit is brought into the plane orthogonal to the optical axis by rolling of the balls. To guide you. With this configuration, it is possible to realize a vibration isolating unit that reduces the driving resistance while preventing displacement of the movable unit in the optical axis direction.

  However, in the ball guide type vibration isolating unit, it is desirable that the ball is disposed at an initial position at the center of the movable range or in the vicinity thereof before starting the vibration isolating operation. In the vibration isolating unit of Patent Document 1, the ball is housed in a recess that is formed on the base member and determines the movable range. When the ball moves greatly from the initial position and is in contact with the side wall surface of the recess, the ball is difficult to roll due to friction with the side wall surface. As a result, the driving resistance of the movable unit increases. Such a deviation from the initial position of the ball often occurs when an impact is applied to the lens device.

  For this reason, in Patent Documents 2 and 3, before driving the ball guide type vibration isolating unit to perform the vibration isolating operation, the movable unit is driven to the two machine directions perpendicular to each other, that is, the vertical and horizontal machine ends, There has been proposed a method for performing an initialization operation for returning to the movable center position. As a result, the ball can be reset to the initial position of the movable range regardless of the position of the ball within the movable range.

Patent Document 3 proposes that the ball position initialization operation should be performed following or simultaneously with the zoom or focus reset operation when the power is turned on.
Japanese Patent Application Laid-Open No. 10-319465 (paragraphs 0026 to 0039, FIGS. 1 and 2, etc.) JP 2001-290184 A (paragraphs 0041-0046, FIG. 5 etc.) JP 2002-196382 A (paragraphs 0074 to 0084, 0137 to 0138, FIG. 5 etc.)

  However, when the photographer observes the subject in real time through the viewfinder as in the single-lens reflex camera system, if the ball position is initialized during the viewfinder observation, the displacement of the subject image due to the initialization operation is observed. . Therefore, the photographer may feel uncomfortable.

  On the other hand, it is preferable to perform the initialization operation at as many timings as possible so as to maintain a state where the driving resistance of the movable unit is low as long as the photographer does not feel uncomfortable.

  The present invention provides a lens apparatus in which the displacement of the subject image caused by the initialization operation of the image stabilization unit (ball position) can be made invisible to the photographer through the viewfinder and the initialization operation is performed as much as possible. This is one of the purposes.

  A lens apparatus according to an aspect of the present invention is detachably attached to a first camera having an optical viewfinder and a second camera not having an optical viewfinder. The lens apparatus includes a movable unit that is movable with respect to a fixed unit for vibration isolation, and a vibration isolation unit that is disposed between the movable unit and the fixed unit and that is movable with movement of the movable unit. Have a unit. Further, when the lens device is mounted on the second camera, initialization processing is performed to move the ball of the image stabilization unit to a predetermined position at a specific timing, and the lens device is mounted on the first camera. In this case, it is characterized by having control means for controlling not to perform the initialization process at the specific timing.

  The lens device according to another aspect of the present invention is detachably attached to a camera having an electronic viewfinder. The lens apparatus includes a movable unit that is movable with respect to a fixed unit for vibration isolation, and a vibration isolation unit that is disposed between the movable unit and the fixed unit and that is movable with movement of the movable unit. Have a unit. Further, a control means for performing an initialization process for moving the ball of the image stabilization unit to a predetermined position when the electronic viewfinder is in a non-display state, and not performing the initialization process when the electronic viewfinder is in a display state. It is characterized by having.

  In the present invention, in a lens apparatus equipped with a ball guide type image stabilization unit, when the attached camera has an optical viewfinder, the initialization process is limited compared to when the camera is not equipped with an optical viewfinder. To do. Therefore, according to the present invention, when the lens apparatus is mounted on a camera having an optical viewfinder, it is possible to prevent the photographer from seeing a change in the viewfinder image due to the initialization process. In addition, when mounted on a camera that does not have an optical viewfinder, the initialization operation is performed at a higher timing than when mounted on a camera that has an optical viewfinder, thereby initializing the state where the drive resistance of the movable unit is low. Can be secured for each. Thereby, it is possible to perform a vibration isolation operation with better accuracy.

  In addition, in a lens apparatus equipped with a ball guide type image stabilization unit, when the electronic viewfinder of the attached camera is in a display state, the initialization process is limited as compared with the case where the electronic viewfinder is in a non-display state. Therefore, according to the present invention, when the electronic viewfinder is in the display state, it is possible to prevent the photographer from seeing a change in the viewfinder image due to the initialization process. Further, when the electronic finder is in the non-display state, the initialization process is performed with more timing than in the display state, so that a state where the drive resistance of the movable unit is low can be ensured for each initialization process. Thereby, it is possible to perform a vibration isolation operation with better accuracy.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows the configuration of a camera system including an interchangeable lens (lens device) that is Embodiment 1 of the present invention. The camera system according to the present embodiment includes a single-lens reflex camera 101 and an interchangeable lens 102 that is detachably attached to the camera 101.

  The light flux from the subject passes through the photographing optical system of the interchangeable lens 102 and proceeds to the inside of the camera 101. In a shooting preparation state before shooting (image recording), a part of the light beam is reflected by a half mirror portion provided at the center of the quick return mirror 103 to form an image on a focus plate (not shown). The light from the focus plate is converted into an erect image by the pentaprism 104, and the photographer can check the subject image as the erect image through an optical finder (hereinafter referred to as OVF) 105.

  When the processing for initialization operation (initialization processing) described later is performed in a state where the subject image formed by the light flux that has passed through the interchangeable lens 102 can be observed in this manner, image fluctuations due to the initialization operation are performed. Will be seen by the photographer. For this reason, in this embodiment, measures are taken to prevent the image fluctuations due to such an initialization operation from being observed, which will be described later.

  A photometric circuit 106 measures the illuminance on the focus plate surface, and inputs the measurement result to a camera system control MPU (hereinafter referred to as a camera controller) 107. The camera controller 107 determines shooting conditions such as exposure time and aperture value based on the photometric result. The photometric sensor in the photometric circuit 106 is divided into a plurality of areas, and a photometric result for each area can be obtained.

  Reference numeral 108 denotes a sub-mirror, which is disposed behind the quick return mirror 103. The light beam that has passed through the half mirror surface of the quick return mirror 103 in the shooting preparation state is reflected by the sub mirror 108 and guided to the AF unit 109.

  The AF unit 109 photoelectrically converts at least a pair of optical images formed by the incident light beam, and calculates the defocus amount of the photographing optical system based on the phase difference between the photoelectric conversion signals. Information on the defocus amount is output to the camera controller 107. The camera controller 107 creates a focus drive command including the target drive amount and drive direction of the focus lens 125 in the interchangeable lens 102 based on the defocus amount information.

  In the photographing operation, the quick return mirror 103 and the sub mirror 108 move to the pentaprism 104 side and retract from the photographing optical path. Further, the focal plane shutter 110 is driven by a shutter drive circuit 111. As a result, the light flux from the subject forms an image on the surface of the image sensor 112 constituted by a CCD sensor or a CMOS sensor. The image sensor 112 photoelectrically converts the subject image and accumulates charges.

  A timing generator 113 controls the charge accumulation operation, the charge read operation, the reset operation, and the like of the image sensor 112.

  Reference numeral 114 denotes a CDS circuit (double correlation sampling circuit) that reduces accumulated charge noise of the image sensor 112, and 115 is a gain control circuit that amplifies the read charge signal (image signal). Reference numeral 116 denotes an A / D converter that converts the amplified imaging signal from analog to digital image data.

  Reference numeral 117 denotes a video signal processing circuit that performs filter processing, color conversion processing, gamma processing, and the like on the image data digitized by the A / D converter 116. The image signal processed by the video signal processing circuit 117 is stored in the buffer memory 118 and displayed on the LCD 119 or recorded on the removable memory card 120.

  Reference numeral 152 denotes a main switch for switching on / off (OFF) the power of the camera 10. Reference numeral 121 denotes an operation unit, which is provided with a dial switch for setting a shooting mode, a recorded image file size, and the like, and release switches (SW1, SW2) for instructing a shooting preparation operation and a shooting operation.

  Reference numeral 151 denotes a battery as a power source for the camera 101. When the main switch 152 is turned on, the power source power (main power source) from the battery 105 is supplied to each part such as the camera controller 107. The main power is also supplied to the interchangeable lens 102 via contacts 152 and 153 provided on a mount (not shown). On the other hand, when the main switch 152 is turned off, other power supply is cut off while leaving a predetermined communication function with the interchangeable lens 102 and a level of power (OFF state power supply) necessary for a predetermined operation of the camera controller 107. The

  The camera controller 107 controls various operations of the camera 101 and communicates with a lens MPU (hereinafter referred to as a lens controller) 124 via the interface circuit 122 and the interface circuit 123 on the interchangeable lens 102 side. In this communication, a focus drive command is transmitted to the interchangeable lens 102, and data such as the operation state and optical information of the camera 101 and the interchangeable lens 102 are transmitted and received.

  In the interchangeable lens 102, a focus lens 125, a zoom lens 126, an anti-vibration lens 127, and a diaphragm 128 are disposed as a part of the photographing optical system.

  The focus lens 125 is driven in the optical axis direction by a focus drive motor 130 constituted by a stepping motor, a vibration type motor, or the like to perform focus adjustment. The focus drive motor 130 is controlled by a focus control circuit 129 that receives a control signal from the lens controller 124. In addition to the focus lens driving circuit, the focus control circuit 128 includes a focus encoder that outputs a signal corresponding to the position of the focus lens 125.

  The zoom lens 126 moves in the optical axis direction when the photographer operates a zoom operation ring (not shown), and performs zooming. The zoom encoder 131 outputs a signal corresponding to the position of the zoom lens 126.

  The anti-vibration lens 127 is driven by a linear actuator 133 controlled by an anti-vibration control circuit (hereinafter referred to as an IS control circuit) 132. The image stabilization operation, that is, the image shake correction operation is performed as follows.

  The angular velocity sensor 135 detects the shake in the pitch direction and the yaw direction of the interchangeable lens 102 (that is, the entire camera system). An output signal from the angular velocity sensor 135 is subjected to signal processing by the signal processing circuit 136 and then input to the lens controller 124. The lens controller 124 calculates the image stabilization drive target position, and sends a drive signal corresponding to the difference between the target position and the position of the image stabilization lens 127 detected by the output from the image stabilization lens encoder 134 to the IS control circuit 132. Output. As described above, the image stabilization operation is performed by feeding back the detection position of the image stabilization lens encoder 134 to the IS control circuit 132.

  The diaphragm 128 is driven by a stepping motor 138 so that its opening diameter changes. The stepping motor 138 is controlled by an aperture control circuit 137 that receives a control signal from the lens controller 124.

  Reference numeral 139 denotes an IS switch for selecting the use (ON) / non-use (OFF) of the image stabilization function.

  Here, the anti-vibration lens 127 of the present embodiment is incorporated in the ball guide type anti-vibration unit shown in FIGS.

  The image stabilization unit 200 corrects image blur in these two directions by moving the image stabilization lens 127 in the pitch direction (vertical direction) and the yaw direction (horizontal direction). The image stabilization unit 200 includes a pitch image stabilization actuator for driving the image stabilization lens 127 in the pitch direction and a yaw image stabilization actuator for driving the image stabilization lens 127 in the yaw direction. Independently controlled. The pitch anti-vibration and yaw anti-vibration actuators correspond to the linear actuator 133 shown in FIG.

  Further, the image stabilization unit 200 includes a pitch direction position detection system that detects the position of the movable unit in the pitch direction P, and a yaw direction position detection system that detects the position in the yaw direction Y. Both the anti-vibration actuators and the both position detection systems have the same configuration and are different in arrangement by 90 degrees. Therefore, hereinafter, only the pitch direction P will be described with respect to the vibration-proof actuator and the position detection system.

  In the figure, the constituent elements indicated by the reference numerals with the subscript p relate to the pitch direction, and the constituent elements indicated by the reference numerals with the subscript y relate to the yaw direction.

  Reference numeral 13 denotes a base member which is a fixing member on the front side of the image stabilization unit 200 and is fixed to the main body of the interchangeable lens 102. Reference numeral 14 denotes a compression coil spring, which is formed of a material that is not attracted to a position detecting and driving magnet, which will be described later, disposed in the vicinity thereof, such as phosphor bronze wire. The front end 14 a of the coil spring 14 is bent outward in the radial direction of the coil spring 14.

  Reference numeral 15 denotes a shift lens barrel that holds the vibration-proof lens 127. The shift barrel 15 is engaged with the front end of the compression coil spring 14 in the optical axis direction so as to be substantially coaxial with the optical axis of the vibration-proof lens 127, and the end 14 a of the coil spring 14 is engaged with the shift barrel 15. Is engaged with a V-groove 15d provided in the.

  Reference numerals 16 a, 16 b, and 16 c denote three balls that are sandwiched between the base member 13 and the shift barrel 15. Each ball is formed of a material that is not attracted by a driving magnet disposed in the vicinity thereof, for example, SUS304 (austenitic stainless steel). The surfaces with which the balls 16a, 16b, and 16c are in contact are 13a, 13b, and 13c on the base member 13 side, and 15a, 15b, and 15c on the shift barrel 15 side, respectively. Each contact surface is a surface orthogonal to the optical axis of the photographing optical system. When the outer diameters of the three balls 16a, 16b, and 16c are the same, the vibration-proof lens 127 is orthogonal to the optical axis by suppressing the difference in distance between the contact surfaces facing in the optical axis direction at three locations. The movement guidance is possible while maintaining the posture to be performed.

  Reference numeral 17 denotes a sensor base which is a fixing member on the rear side, the position of which is determined by two positioning pins, and is coupled to the base member 13 by two screws. The rear end portion of the compression coil spring 14 engages with the sensor base 17 and is fixed to the sensor base 17 by adhesion or the like. The compression coil spring 14 is compressed between the shift barrel 15 and the sensor base 17. Thereby, each contact surface of the shift barrel 15 and the base member 13 comes into pressure contact with the three balls 16a, 16b, and 16c.

  Lubricating oil is disposed between the three balls 16a, 16b, 16c and the contact surface. The lubricating oil has such a viscosity that the balls do not easily fall off the contact surface even when the balls are not sandwiched between the base member 13 and the shift barrel 15. As a result, an inertial force exceeding the urging force of the coil spring 14 acts on the shift barrel 15, and even when the ball is in a non-nipping state, it is possible to prevent the ball from easily deviating.

  Next, the configuration of the pitch direction vibration isolation actuator will be described. Reference numeral 18p denotes a driving magnet that is two-pole magnetized in a radial direction centered on the optical axis. Reference numeral 19p denotes a yoke for closing the magnetic flux on the front side in the optical axis direction of the drive magnet 18p. A coil 20p is fixed to the shift barrel 15 by bonding.

  Reference numeral 21 denotes a yoke for closing the magnetic flux on the rear side in the optical axis direction of the drive magnet 18p. The yoke 21 is fixed to the base member 13 by a magnetic force so as to form a space in which the coil 20p moves with respect to the drive magnet 18p. Thereby, a closed magnetic circuit is formed.

  When a current is passed through the coil 20p, Lorentz force is generated by repulsion between the magnetic lines generated in the magnet 18p and the coil 20p in a direction substantially perpendicular to the magnetization boundary of the driving magnet 18p, and the shift barrel 15 is moved. Let This configuration is called a so-called moving coil type.

  In the vibration isolation unit 200, a yaw direction vibration isolation actuator having the same configuration as the above pitch direction vibration isolation actuator is disposed. As a result, the movable unit constituted by the anti-vibration lens 127 and the shift barrel 15 can be driven in the pitch direction and the yaw direction orthogonal to the optical axis and orthogonal to each other.

  Here, the relationship between the base member 13 and the movable unit (shift barrel 15) with respect to the ball 16b will be described with reference to FIG. The other balls 16a and 16c have the same relationship.

  In FIG. 4A, the shift lens barrel 15 is at its movable center position (a position where the optical axis of the vibration-proof lens L1 coincides with or substantially coincides with the optical axis of the lens unit 120). The ball 16b is also positioned at the center of the ball movement range determined by the frame portion 13d formed around the contact surface 13b of the base member 13. The frame portion 13d is a limiting portion for preventing the ball 16b from moving beyond the ball movement range.

  FIG. 4B shows a state in which the shift barrel 15 is driven in the downward arrow direction from this state. The shift barrel 15 is driven to a machine end (not shown) provided on the base member 13 and moved by a from the movable center position.

  Since the ball 16b is held between the base member 13 and the shift barrel 15, the ball 16b rolls in the direction of the arrow from the position shown in FIG. 4A and moves to the position shown in FIG. The rolling friction of the ball 16b is sufficiently smaller than the sliding friction, and the ball 16b and the contact surfaces 13b and 15b do not slip. For this reason, the shift barrel 15 moves relative to the base member 13 while being guided by the rolling of the ball 16b. At this time, the shift barrel 15 and the base member 13 are moved in the opposite directions relative to the center of the ball 16b. Therefore, the movement amount of the ball 16b with respect to the base member 13 is half of the movement amount of the shift barrel 15. That is, as shown in FIG. 4B, the movement amount b of the ball 16b is half of a (a / 2).

  FIG. 4C shows the base member 13 and the ball 16b when the state of FIG. 4A is viewed from the rear side in the optical axis direction. The ball 16b is located at the center of the movement range in the pitch direction and the yaw direction. A frame portion 13d is shown around the ball 16b and the contact surface 13b. The distance between the inner side surfaces of the frame portion 13d, that is, the size in the pitch direction and the yaw direction of the ball movement range is represented by (r + b + c) from the center, where r is the radius of the ball 16b. Note that c is a mechanical margin.

  When the ball 16b is at a position deviated by c or more from the center of the ball movement range shown in FIG. 4C, when the shift barrel 15 is driven as shown in FIG. Before the cylinder 15 moves by a and abuts against the machine end, it abuts against the inner surface of the frame portion 13d. Then, after the ball 16b comes into contact with the inner surface of the frame portion 13d, the shift barrel 15 is driven to the machine end while sliding with respect to the ball 16b. When the shift lens barrel 15 is returned to the movable center position from this state, the ball 16b rolls back to a position at a distance c from the center of the ball movement range.

  In this way, by driving the shift barrel 15 to the machine end and then returning it to the movable center position, the center of the ball 16b is the same as shown in FIG. It is located in a rectangular area having a side c from the center of the ball movement range. That is, the ball 16b returns to the initial position (reset position) that is near the center of the ball movement range.

  In this embodiment, this series of operations is referred to as a ball reset operation (initialization operation: first operation). This initialization operation is performed as an operation different from the image stabilization operation of the image stabilization unit 200 based on the output of the vibration sensor 117.

  When the shift barrel 15 is simultaneously driven in the pitch direction and the yaw direction by the same amount, the shift barrel 15 moves to a position that is √2 times the drive amount in each direction in a direction that forms 45 degrees with respect to the pitch direction and the yaw direction. For this reason, in the actual use state, the shift barrel 15 is not driven completely independently in the pitch direction and the yaw direction, and takes into account the other position and is circular or close to circular with the optical axis as the center. The shift barrel 15 is driven within the polygonal range. The three balls 16a, 16b, and 16c are similar to the shape of the range and roll in a range having a half size.

  The ball movement range is a rectangle having sides parallel to the pitch direction and the yaw direction. If the ball movement range is a circular or polygonal shape according to the range of movement of the ball in the actual use state described above, the ball does not move to a position where it comes into contact with the frame portion 13d even if the reset operation is performed. This is not preferable because a correct reset operation cannot be performed.

  In this embodiment, the ball movement range is a rectangle having sides parallel to the pitch direction and the yaw direction. When the ball is shifted to the two adjacent sides (corner portions), the gap between the ball and the other two sides is mechanically moved in the direction of the other two sides of the shift barrel 15. The ball movement range is set to be slightly larger than half of the maximum movable amount or the maximum moving amount in actual use. If the ball reset operation is performed under such setting, the ball does not hit the frame portion 13d in actual use, and the shift barrel 15 can be guided only by rolling the ball.

  In addition, as described above, the lubricating oil is disposed between the ball and the contact surface, thereby reducing the sliding friction between the ball and the contact surface and reducing the influence on the position control of the movable unit. it can.

  In the present embodiment, the case where the frame portion 13d for limiting the movement range of the ball is provided in the base member 13 has been described, but this may be provided in the shift barrel 15. In this embodiment, the case where three balls are used has been described, but the number of balls is not limited to this in the present invention.

  Next, the image stabilizing lens encoder 134 as the position detecting means shown in FIG. 1 will be described.

  2 and 3, reference numerals 22p and 22y are detection magnets magnetized in two poles in the radial direction centered on the optical axis. Reference numerals 23p and 23y are yokes disposed on the front side of the detection magnets 22p and 22y for closing the magnetic flux. The detection magnets 22p and 22y and the yokes 23p and 23y are fixed to the shift barrel 15.

  Reference numerals 24p and 24y denote Hall elements that convert a change in magnetic flux density into an electrical signal, and are positioned and fixed to the sensor base 17.

  Reference numeral 25 denotes a flexible substrate for electrically connecting the coil 20p and the hall element 24p constituting the pitch direction position detection system to an external circuit. The flexible substrate 25 is folded back at a portion 25a. A Hall element 24p is mounted on the front side in the optical axis direction of the portion 26p. The hall element 24p is fixed to the sensor base 17.

  The folded portion further has three bent portions, and a pin 29p formed in the shift barrel 15 is inserted into a hole 28p formed in the tip portion 27p. The distal end portion 27p is rotatable around the pin 29p. Further, the terminals of the coil 20p are soldered to the land portions 30p and 31p provided at the tip portion 27p.

  The yaw direction position detection system includes a hall element 24y fixed to the coil 20y and the sensor base 17, and these are also electrically connected to an external circuit by a flexible substrate 25.

  Reference numeral 32 denotes a pressing plate for fixing the flexible substrate 25 to the sensor base 17 and is fixed to the sensor base 17 by a single screw.

  The positions of the shift barrel 15 in the pitch direction and the yaw direction are detected by the anti-vibration lens encoder 134 in the pitch direction and the yaw direction configured as described above.

  Here, FIG. 5 shows the state of the magnetic flux behind the detection magnet 22p. In FIG. 5, the horizontal axis indicates the position in the radial direction centered on the optical axis, and the vertical axis indicates the magnetic flux density.

  When the boundary portion of the two-pole magnetization of the detection magnet 22p is located at the central position on the horizontal axis, the magnetic flux density is zero (0). In this state, the optical axis of the anti-vibration lens 127 is substantially coincident with the optical axes of the other lenses in the photographing optical system.

  In FIG. 5, the magnetic flux density changes linearly to such an extent that there is no practical problem within the range sandwiched between two-dot chain lines. By outputting an electrical signal corresponding to the change in magnetic flux density from the Hall element, the position of the image stabilizing lens 127 can be detected.

  In the ball guide type anti-vibration unit configured as described above, it is desirable to perform an initialization operation before the start of the anti-vibration operation. However, in the initialization operation, the shift barrel 15 (anti-vibration lens 127) is driven to the machine ends on both sides in the pitch and yaw directions and then returned to the center position. For this reason, the image is moved in the pitch and yaw directions by this initialization operation. Then, the movement of the image is observed by the photographer through the OVF 105, which may cause discomfort to the photographer.

  However, when the interchangeable lens 102 is attached to the camera 101, it is unlikely that the photographer is looking at the OVF 105. Therefore, if the initialization operation is performed at this timing, there is little possibility that the photographer will feel uncomfortable.

  On the other hand, consider the case where the interchangeable lens 102 is attached to a camera 141 that does not have an OVF as shown in FIG. A camera 141 shown in FIG. 6 includes an electronic viewfinder (hereinafter referred to as EVF) that displays an image of a subject on the LCD 119, and a photographer performs photographing while observing the subject image displayed on the EVF. In the camera 141 of FIG. 6, the same components as those in the camera 101 of FIG.

  The LCD 119 does not display when the main switch 152 is turned off and when the switch for switching the display (ON) / non-display (OFF) of the EVF is turned off. That is, when any of the switches is OFF, the photographer cannot observe the subject image formed by the light beam passing through the interchangeable lens 102.

  Therefore, when the interchangeable lens 102 is attached to a camera 141 that does not have an OVF and has an EVF, first, the initialization operation is performed when the main switch 152 is switched from OFF to ON (when the main power is turned on). It is possible to do it. That is, if the initialization operation is performed after the main switch 152 is turned on and before the LCD 119 displays the subject image, the photographer is not uncomfortable.

  The operation of the interchangeable lens 102 of the present embodiment based on the above concept will be described with reference to the flowcharts of FIGS. This operation is executed according to a computer program stored in the lens controller 124. In the following description, the camera 101 provided with the OVF is referred to as an OVF camera, and the camera provided with the EVF without the OVF is referred to as an EVF camera.

  When the interchangeable lens 102 is attached to the OVF camera 101 or EVF camera 141 in which the main switch 152 is in the OFF state, the OFF state power is supplied from the battery 151 to the lens controller 124, and the operation starts from Step 200 in FIG. Start.

(Step 200)
The lens controller 124 performs initial settings for lens control and image stabilization control.

(Step 201)
Camera ID information including the model number of the camera is acquired through communication with the camera. From the camera ID information acquired here, it is possible to determine whether the camera to which the interchangeable lens 102 is attached is the OVF camera 101 or the EVF camera 141 in step 206 described later.

(Step 202)
The lens controller 124 controls the linear actuator 133 through the IS control circuit 132 to perform the initialization operation of the image stabilization unit 200. The contents of the initialization operation are as described above. In this embodiment, the initialization operation is always performed at the timing according to the attachment to the camera, regardless of whether the camera is the OVF camera 101 or the EVF camera 141. The timing according to the mounting on the camera means not only the time of mounting on the camera but also a period (in this embodiment, a period before the main switch 152 is switched from OFF to ON). . The same applies to the embodiments described later.

(Step 203)
When the initialization operation is completed, the initialization completion flag TD_INIT is set to 1.

(Step 204)
The lens controller 124 detects various switch states and detects the positions of the zoom lens 126 and the focus lens 125. Examples of the switch include a switch for switching between auto focus and manual focus, and an IS switch 139.

(Step 205)
The lens controller 124 determines whether the main switch 152 of the camera is ON. This is determined in serial communication interrupt processing described later. If the main switch 152 is OFF, the process proceeds to step 206. On the other hand, if the main switch 152 is ON, the process proceeds to step 208.

(Step 206)
The lens controller 124 determines whether or not the camera to which the interchangeable lens 102 is attached is the OVF camera 101. This is determined based on the camera ID information acquired in step 201. If it is the OVF camera 101, the process proceeds to step 211, and if it is the EVF camera 141, the process proceeds to step 207.

(Step 207)
Since the interchangeable lens 102 is attached to the EVF camera 141, the lens controller 124 clears the initialization completion flag TD_INIT to 0. Then, the process proceeds to Step 211.

(Step 208)
The lens controller 124 determines whether or not the initialization completion flag TD_INIT is 1, that is, whether or not the initialization operation has been completed. If completed, the process proceeds to step 211, and if not completed, the process proceeds to step 209.

(Step 209)
Similar to step 202, the lens controller 124 controls the linear actuator 133 through the IS control circuit 132 to perform the initialization operation of the image stabilization unit 200. The initialization operation in this step is performed only when the interchangeable lens 102 is attached to the EVF camera 141. Then, the process proceeds to Step 210. In this embodiment, when the camera to which the interchangeable lens 102 is attached is the EVF camera 141 as described above, the initialization operation is performed at a timing according to switching of the main switch 152 from OFF to ON. The timing according to the switching of the main switch 152 from OFF to ON means not only the switching time but also a period including this (for example, a period before the EVF display on the LCD 119 is started). The same applies to other embodiments described later.

(Step 210)
Since the initialization operation is completed, the initialization completion flag TD_INIT is set to 1. Then, the process proceeds to Step 211.

(Step 211)
The lens controller 124 determines whether or not a focus drive command has been received from the camera. If a focus drive command has been received, the process proceeds to step 212. If not received, the process proceeds to step 216.

(Step 212)
The focus drive command from the camera includes information on the target drive amount and drive direction of the focus lens 125. The lens controller 124 can count the number of drive pulses of the focus drive motor 130 by a focus encoder (not shown) in the focus control circuit 29. Therefore, the lens controller 124 drives the focus drive motor 130 until the drive pulse count value reaches the number of pulses corresponding to the target drive amount (hereinafter referred to as the target pulse number), and performs focus control.

(Step 213)
Next, the lens controller 124 determines whether or not the drive pulse count value has reached the target pulse number P. If the target number of pulses P has been reached, the process proceeds to step 214, and if not, the process proceeds to step 215.

(Step 214)
Since the drive pulse count value has reached the target pulse number P, the lens controller 124 stops driving the focus lens 125. Then, the process proceeds to Step 216.

(Step 215)
Since the drive pulse count value does not reach the target pulse number P, the speed of the focus drive motor 130 is set according to the remaining drive pulse number. Decelerate as the number of remaining drive pulses decreases. Then, the process proceeds to Step 216.

(Step 216)
The lens controller 124 determines whether or not a command for stopping all driving, that is, driving of all actuators in the interchangeable lens 102 has been received from the camera. When a state where no operation is performed on the camera side continues for a predetermined time, the all drive stop command is transmitted from the camera. If an all drive stop command has been received, the process proceeds to step 217. If not received, the process returns to step 204.

(Step 217)
The lens controller 124 performs full drive stop control. Here, the driving of all the actuators is stopped, and the lens controller 124 itself enters a sleep state. The power supply to the image stabilization unit 200 is also stopped. Thereafter, when any operation is performed on the camera side, the camera transmits a sleep cancel command to the interchangeable lens 200, and the lens controller 124 cancels the sleep state.

  If there is a serial communication interrupt or IS control interrupt request from the camera during the sleep state, the interrupt processing is performed.

  The serial communication interrupt process decodes communication data and performs lens processing such as aperture driving and focus lens driving according to the decoding result. Then, by decoding the communication data, it is possible to determine ON of the camera main switch 152, SW1ON and SW2 of the release switch, shutter speed, and the like.

  The IS control interrupt is a timer interrupt that is generated at regular intervals, and the anti-vibration unit 200 is driven in the pitch direction and the yaw direction by processing the interrupt.

  Here, the serial communication interrupt will be described with reference to the flowchart of FIG. When receiving a serial communication interrupt request from the camera, the lens controller 124 starts its operation from step 300.

(Step 300)
The lens controller 124 analyzes a command (command) from the camera and proceeds to processing according to each command.

(Step 301)
If a focus drive command is received from the camera, the process proceeds to the next step 302.

(Step 302)
The lens controller 124 sets the speed of the focus drive motor 130 according to the target pulse number, and starts driving the focus lens 125.

(Step 303)
If an aperture drive command is received from the camera, the process proceeds to step 304.

(Step 304)
The lens controller 124 drives the diaphragm 128 based on the diaphragm driving data transmitted from the camera. Specifically, the drive pattern of the stepping motor 138 is set, and the stepping motor 138 is operated via the aperture control circuit 137 according to the drive pattern. Thereby, the diaphragm 128 is driven.

(Step 305)
If lens status communication is received from the camera, the process proceeds to step 306.

(Step 306)
In this step, the lens controller 124 transmits information indicating the focal length information of the lens and the operation state of the image stabilization unit 200 to the camera. In addition, information about the status status of the camera (the status of the main switch 152 and the release switch, the display status of the EVF, etc.) is received from the camera.

(Step 307)
If ID information is received from the camera, the process proceeds to step 308.

(Step 308)
The lens controller 124 receives the above-described camera ID information and transmits the ID information of the interchangeable lens 102 to the camera. The received data is stored in the RAM in the lens controller 124. This process is the same as that performed when the interchangeable lens 102 is attached to the camera (step 201).

(Step 309)
When a command other than the above, for example, a request for transmission to the camera side such as focus sensitivity data of the interchangeable lens 120 or optical data of the interchangeable lens 102 is received from the camera, transmission to them is performed in step 310.

  Next, the IS control interrupt will be described with reference to the flowchart of FIG.

  When an IS control interrupt occurs, the lens controller 124 starts IS control from step 400 in FIG.

(Step 400)
The lens controller 124 A / D converts the output signal from the angular velocity sensor 135 processed by the signal processing circuit 136.

(Step 401)
Next, the lens controller 124 performs a high-pass filter operation in order to cut the low frequency component. The high-pass filter time constant is switched for a predetermined time from the start of calculation, and an operation for quickly stabilizing the signal is also performed.

(Step 402)
Next, the lens controller 124 performs an integration calculation using the calculation result of the high-pass filter as an input. This result is angular displacement data.

(Step 403)
Next, the lens controller 124 reads out image stabilization sensitivity data corresponding to the zoom lens position and the focus lens position from the memory in the lens controller 124, and sets the target drive amount of the image stabilization lens 127 (in the direction to cancel image blur). Drive amount) SFTDRV is calculated.

(Step 404)
Next, the lens controller 124 A / D converts the signal of the image stabilization lens encoder 34 that detects the amount of movement of the image stabilization lens 27. Then, the result of the A / D conversion is stored in the RAM area in the lens controller 124 as a detected movement amount SFTPST.

(Step 405)
Next, the lens controller 124 performs a feedback calculation (SFTDRV-SFTPST). The calculation result is stored in the RAM area as a difference value SFT_DT.

(Step 406)
Next, the lens controller 124 multiplies the loop gain LPG_DT by the difference value SFT_DT that is the calculation result in Step 412. Then, the calculation result is stored in the RAM area as a drive pulse SFT_PWM.

(Step 407)
Further, the lens controller 124 performs a phase compensation calculation on the drive pulse SFT_PWM in order to obtain a stable control system.

(Step 408)
Then, the lens controller 124 outputs the calculation result of step 407 as an output pulse PWM, and ends the IS control interrupt. The output pulse PWM is input to a driver circuit in the IS control circuit 132. When the linear motor 133 is driven by the driver circuit, the anti-vibration lens 127 moves and image blur correction is performed.

  As described above, in this embodiment, if the camera to which the interchangeable lens 102 is attached is the OVF camera 101, the image stabilization unit is only at the timing according to the attachment to the camera (the timing before the main switch 152 is turned on). Initialize operation. On the other hand, when the camera to which the interchangeable lens 102 is attached is the EVF camera 141, the initialization operation is performed at the timing according to the attachment to the camera and at the timing according to the main switch 152 being switched from OFF to ON in the camera. I do.

  As a result, regardless of whether the interchangeable lens 102 is attached to either the OVF camera 101 or the EVF camera 141, the initialization operation can be performed without observing a change in the finder image associated with the initialization operation. Accordingly, it is possible to secure a state in which the driving resistance of the vibration isolating unit 200 is small and perform the vibration isolation with high accuracy.

  In the first embodiment, the case where the image stabilizing unit is initialized at the timing corresponding to the mounting of the interchangeable lens to the camera, both when the interchangeable lens is mounted on the OVF camera and when mounted on the EVF camera, will be described. did. However, the present invention is not limited to this, and in any of the above cases, the initialization operation may not be performed at a timing according to the mounting of the interchangeable lens to the camera.

  The operation of the lens controller 124 in this case is shown in the flowchart of FIG. 10 as Embodiment 2 of the present invention.

  This embodiment is different from the operation shown in FIG. 7 in the first embodiment in that there is no step 202 for performing the initialization operation at the timing according to the mounting of the interchangeable lens on the camera. The other steps are the same. Thereby, in this embodiment, if the camera to which the interchangeable lens 102 is attached is the OVF camera 101, the initialization operation of the image stabilization unit 200 is not performed. On the other hand, when the camera to which the interchangeable lens 102 is attached is the EVF camera 141, the initialization operation is performed only at the timing corresponding to the switching of the main switch 152 from OFF to ON.

  Thereby, when the interchangeable lens 102 is attached to the EVF camera 141, the initialization operation can be performed without observing a change in the finder image accompanying the initialization operation. On the other hand, when the camera is attached to the OVF camera 101, the initialization operation itself is not performed. Therefore, it is possible to reliably avoid at least the observation of the variation in the finder image accompanying the initialization operation. For example, it is effective when the photographer is expected to watch the OVF even when the lens is attached to the camera.

  In the first embodiment, whether or not to perform an initialization operation at a timing according to the main switch 152 being switched from OFF to ON is determined depending on whether or not the camera to which the interchangeable lens is attached is an EVF camera. Explained when to do. However, regardless of whether the main switch 152 is switched from OFF to ON, whether or not to perform the initialization operation may be determined according to whether or not the camera is an EVF camera.

  The operation of the lens controller 124 in this case is shown in the flowchart of FIG. 11 as Embodiment 3 of the present invention. In FIG. 11, steps having the same contents as the steps in the flowchart of FIG. 7 are assigned the same reference numerals as in FIG.

  This embodiment corresponds to the flowchart shown in FIG. 7 in which steps 202, 203, 205 to 210 are deleted and steps 502 and 503 are added between steps 201 and 204.

  In step 502, based on the camera ID information acquired in step 201, it is determined whether the camera to which the interchangeable lens is attached is the OVF camera 101 or the EVF camera 141.

  If the camera is an EVF camera, the image stabilizing unit is initialized in step 503. On the other hand, in the case of an OVF camera, the initialization operation is not performed.

  According to the present embodiment, it is possible to obtain the same effects as those of the second embodiment.

  In the first embodiment, when the interchangeable lens is attached to the EVF camera, the case where the initialization operation is performed at the timing according to the switching of the main switch 152 from OFF to ON has been described. However, whether or not to perform the initialization operation may be changed depending on whether or not EVF is displayed. As described above, if the switch for switching the display (ON) / non-display (OFF) of the EVF is turned off, the EVF is not displayed even if the main switch 152 is turned on. This is because the subject image is not seen.

  The operation in this case will be described as a fourth embodiment of the present invention with reference to the flowchart shown in FIG. In this flow, Step 200 to Step 204 and Step 211 to Step 217 are the same as those in the flowchart shown in FIG.

  In step 202, regardless of whether the camera to which the interchangeable lens 102 is attached is the OVF camera 101 or the EVF camera 141, the image stabilization unit 200 is initialized at a timing according to the attachment to the camera. From step 204, the process proceeds to step 601.

(Step 601)
The lens controller 124 determines whether the camera to which the interchangeable lens 102 is attached is the OVF camera 101 or the EVF camera 141. This is determined based on the camera ID information acquired from the camera in step 201. If it is the OVF camera 101, the process proceeds to step 211, and if it is the EVF camera 141, the process proceeds to step 602.

(Step 602)
It is determined whether the EVF of the EVF camera 141 is in a display state or a non-display state. Information indicating the state of the EVF is obtained by status communication with the camera performed in step 305 and step 306 in the flowchart of FIG. 8 of the first embodiment. Information indicating whether the main switch 152 of the camera is ON may be used as information indicating the state of the EVF. If the EVF is in the display state, the process proceeds to step 603, and if the EVF is in the non-display state, the process proceeds to step 604.

(Step 603)
Since EVF is in the display state, the lens controller 124 clears the initialization completion flag TD_INIT to 0.

(Step 604)
Since the EVF is in the non-display state, it is determined whether or not the initialization completion flag TD_INIT is 1, that is, whether or not the initialization operation of the image stabilization unit 200 has been completed. If completed, the process proceeds to step 211, and if not completed, the process proceeds to step 605.

(Step 605)
The initialization operation of the image stabilization unit 200 is performed. Then, the process proceeds to Step 606.

(Step 606)
Since the initialization operation is completed, the initialization completion flag TD_INIT is set to 1. Then, the process proceeds to Step 211.

  According to the present embodiment, when the interchangeable lens 102 is attached to the EVF camera 141, if the EVF is in a non-display state, even if the main switch 152 is ON (of course, OFF), the image stabilization unit 200 initialization operations can be performed. Further, the photographer does not observe fluctuations in the subject image due to this.

  In the fourth embodiment, the case where the image stabilizing unit is initialized at the timing corresponding to the mounting of the interchangeable lens to the camera, both when the interchangeable lens is mounted on the OVF camera and when mounted on the EVF camera, will be described. did. However, in any of the above cases, the initialization operation may not be performed at the timing according to the mounting of the interchangeable lens to the camera.

  The operation in this case is shown in the flowchart of FIG. This flowchart corresponds to a flowchart obtained by deleting step 202 from the flowchart of FIG. 12 of the fourth embodiment, and other steps are the same as those of the fourth embodiment.

  Thereby, when the interchangeable lens 102 is attached to the EVF camera 141, the initialization operation can be performed without observing a change in the finder image accompanying the initialization operation. On the other hand, when the camera is attached to the OVF camera 101, the initialization operation itself is not performed. Therefore, it is possible to reliably avoid at least the observation of the variation in the finder image accompanying the initialization operation. For example, it is effective when the photographer is expected to watch the OVF even when the lens is attached to the camera.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the claims.

  For example, in each of the above embodiments, the OVF camera 101 that does not have an EVF has been described. However, by devising the light guiding method to the AF unit 109, the light transmitted through the half mirror part of the quick return mirror 103 can be guided to the image sensor 112, and the EVF function can be provided. In this case, it is conceivable that when the EVF is used, the optical path to the OVF 105 is shielded so that the subject cannot be observed by the OVF 105. In such a case, the lens controller determines that the OVF is not in use (ie, the EVF is in use) by status communication with the OVF camera. The OVF camera with EVF may be handled in the same manner as the EVF camera shown in each embodiment. For example, after the main switch is switched from OFF to ON, the image stabilization unit may be initialized in a non-display state before the EVF enters the display state.

1 is a block diagram illustrating a camera system including an interchangeable lens and an OVF camera that are Embodiment 1 of the present invention. FIG. FIG. 3 is an exploded perspective view of a vibration isolation unit mounted on the interchangeable lens of Example 1. FIG. 3 is an exploded perspective view of a vibration isolation unit mounted on the interchangeable lens of Example 1. FIG. 3 is a diagram illustrating a relationship among a ball, a shift base, and a shift barrel in the vibration isolation unit according to the first embodiment. The figure which shows the state of the magnetic flux from the magnet for a detection in the vibration proof unit of Example 1. FIG. FIG. 3 is a block diagram illustrating a camera system including the interchangeable lens and the EVF camera according to the first embodiment. 6 is a flowchart showing the operation of the interchangeable lens of Example 1. 6 is a flowchart showing the operation of the interchangeable lens of Example 1. 3 is a flowchart illustrating a control operation of the image stabilization unit according to the first embodiment. 9 is a flowchart showing the operation of an interchangeable lens that is Embodiment 2 of the present invention. 9 is a flowchart showing the operation of an interchangeable lens that is Embodiment 3 of the present invention. 9 is a flowchart showing the operation of an interchangeable lens that is Embodiment 4 of the present invention. 9 is a flowchart showing the operation of an interchangeable lens that is Embodiment 5 of the present invention.

Explanation of symbols

101 OVF camera 102 Interchangeable lens 103 Quick return mirror 105 Optical viewfinder (OVF)
107 Camera Controller 108 Sub Mirror 112 Image Sensor 119 LCD
124 Lens controller 125 Focus lens 126 Zoom lens 127 Anti-vibration lens 132 IS control circuit 133 Anti-vibration linear actuator 134 Anti-vibration lens encoder 135 Angular velocity sensor 139 IS switch 141 EVF camera

Claims (9)

A lens device that is detachably attached to a first camera having an optical finder and a second camera not having an optical finder,
A movable unit movable with respect to a fixed unit for vibration isolation, and a vibration isolation unit disposed between the movable unit and the fixed unit and having a ball movable with the movement of the movable unit;
When the lens device is mounted on the second camera, an initialization process is performed to move the ball of the image stabilization unit to a predetermined position at a specific timing, and the lens device is applied to the first camera. And a control unit that controls not to perform the initialization process at the specific timing when the lens apparatus is mounted.   The lens device according to claim 1, wherein the specific timing is a timing corresponding to mounting of the lens device to the camera.   The lens device according to claim 1, wherein the specific timing is a timing corresponding to switching of the power switch from a power-off state to a power-on state when the lens device is mounted on the camera.   4. The control unit according to claim 1, wherein the control unit performs the initialization process at a second timing different from the first timing when the lens apparatus is attached to the first camera. 5. The lens apparatus as described in any one.   The control means performs the initialization process at a timing different from the specific timing when the lens device is attached to the first camera and when attached to the second camera. The lens device according to any one of claims 1 to 4. The specific timing is a timing according to the mounting of the lens device to the camera,
The lens apparatus according to claim 4, wherein the timing different from the specific timing is a timing according to switching of a power switch from a power-off state to a power-on state. A lens device detachably attached to a camera having an electronic viewfinder,
A movable unit movable with respect to a fixed unit for vibration isolation, and a vibration isolation unit disposed between the movable unit and the fixed unit and having a ball movable with the movement of the movable unit;
When the electronic viewfinder is in a non-display state, an initialization process for moving the ball of the image stabilization unit to a predetermined position is performed, and when the electronic viewfinder is in a display state, the initialization process is not performed. And a control means for controlling the lens device. A lens apparatus according to any one of claims 1 to 7;
A camera system comprising: a camera to which the lens device is detachably mounted. A lens apparatus according to any one of claims 1 to 6;
A camera system in which the lens apparatus is detachably mounted, and includes a first camera having an optical finder and a second camera not having an optical finder.