JP2009169291A - Optical equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform inclination adjustment of an optical axis of a correction lens without generating change in thrust generated by an actuator in a vibration-proof unit. <P>SOLUTION: The vibration-proof unit 60 includes: a holding member 101 which holds a vibration-proof element L3; a base member 102 which holds the holding member to be shifted; a first actuator and second actuator constituted of coils 105p, 105v provided to one of the holding member and the base member, and a magnet 104m provided to the other, respectively. The vibration-proof unit is held by a lens barrel member by engagement of three held members 109e, 110f, 110f provided to the base member into an engagement part 21 formed in the lens barrel member, two members 110f to be held have eccentric parts 110h eccentric to center axes of the held members, and the eccentric parts are engaged into the engagement part. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optical apparatus such as a digital still camera, a video camera, and an interchangeable lens, and more particularly to an optical apparatus including a vibration isolating unit that performs optical vibration isolation by shifting a vibration isolating element such as a lens.

  The anti-vibration unit shifts a lens (hereinafter referred to as a correction lens) in a direction to reduce image blur by controlling an actuator in accordance with an output from a shake sensor provided in the optical device.

  Such a vibration isolation unit is assembled using a large number of parts. For this reason, accumulation of manufacturing errors of each component makes it impossible to hold the correction lens at a predetermined position, and as a result, the optical performance of the imaging optical system is degraded.

  Further, in order to reduce the size of the imaging optical system and improve the magnification, it is necessary to improve the processing accuracy and position accuracy of the correction lens itself. And the fall of processing accuracy and position accuracy leads also to the fall of the optical performance of an imaging optical system.

  Patent Document 1 discloses a vibration isolating unit that can adjust the inclination of the optical axis of a correction lens in order to prevent such a decrease in optical performance. The image stabilization unit includes a lens holding frame that holds the correction lens, a base frame that holds the lens holding frame in a shiftable manner, and two actuators that shift-drive the lens holding frame in two directions orthogonal to the optical axis. . Each actuator includes a coil provided on the lens holding frame and a magnet provided on the base frame.

A reference pin is provided between two actuators of the lens holding frame, and the reference pin is engaged with a groove formed in the base frame. The base frame is provided with two eccentric pins, and the two eccentric pins engage with two grooves formed in the lens holding frame, respectively. The reference pin and the two eccentric pins function as a guide member that guides the lens holding frame in the direction orthogonal to the optical axis with respect to the base frame. Further, by rotating the eccentric pin, the lens holding frame can be tilted with respect to the base frame around the reference pin. Thereby, the inclination of the optical axis of the correction lens with respect to the optical axis of the imaging optical system can be adjusted.
Japanese Patent No. 3794522

  However, in the image stabilization unit disclosed in Patent Document 1, when the lens holding frame is tilted with respect to the base frame due to the rotation of the eccentric pin, the distance between the coil and the magnet constituting the actuator changes. This causes a change in the thrust generated by the actuator, making it difficult to accurately control the shift amount of the lens holding frame.

  A cam follower provided on the outer periphery of the vibration isolation unit (base frame) engages with a cam ring cam disposed on the outer periphery of the vibration isolation unit. Some optical instruments have a moving structure. In such an optical apparatus, the center of gravity of the image stabilization unit is located between the two actuators. The cam follower disposed in the vicinity of the center of gravity is larger than the other cam follower disposed at a position away from the center of gravity, and is easily damaged.

  The present invention provides an optical apparatus capable of adjusting the inclination of the optical axis of a correction lens without causing a change in the thrust generated by an actuator in a vibration isolation unit. In addition, the present invention provides an optical apparatus that can avoid damage to members such as a cam follower disposed near the center of gravity of the vibration isolation unit when an impact is applied.

  An optical apparatus according to one aspect of the present invention includes a vibration isolating unit and a lens barrel member that holds the vibration isolating unit. The anti-vibration unit includes a holding member that holds the anti-vibration element, a base member that holds the holding member so as to be shiftable with respect to the optical axis of the optical system, and a coil provided on one of the holding member and the base member. A first actuator and a second actuator, each of which is configured by a magnet provided on the other side and shifts the holding member in two different directions with respect to the optical axis. The anti-vibration unit is held by the lens barrel member by engaging three held members provided on the base member with engaging portions formed on the lens barrel member. Of the three members to be held, two members to be held have eccentric portions that are eccentric with respect to the central axis of the members to be held, and the eccentric portions are engaged with the engaging portions. Features.

  An optical apparatus according to another aspect of the present invention includes a vibration isolating unit and a lens barrel member that holds the vibration isolating unit. The anti-vibration unit includes a holding member that holds the anti-vibration element, a base member that holds the holding member in a shiftable manner with respect to the optical axis, and the holding member in two different directions with respect to the optical axis of the optical system. A first actuator and a second actuator to be shifted. The anti-vibration unit is held by the lens barrel member by engaging three held members provided on the base member with engaging portions formed on the lens barrel member. Further, the first and second actuators are arranged so that the phases are 90 degrees different from each other when viewed in the optical axis direction. Further, one of the three members to be held is provided within a range of 90 degrees with the arrangement phases of the first and second actuators as both ends of the base member as viewed in the optical axis direction. . The one held member has a higher strength than the other two held members.

  According to the present invention, by rotating the held member having the eccentric portion, it is possible to adjust the inclination of the entire vibration isolation unit including the vibration isolation element. Therefore, the inclination of the vibration isolation element can be adjusted without changing the distance between the coil and the magnet constituting the actuator, that is, without changing the thrust generated by the actuator.

  Further, according to the present invention, the strength of the held member disposed near the center of gravity of the vibration isolator unit is made higher than the strength of the other held members, so that the vicinity of the center of gravity due to the impact received by the fall of the optical device or the like It is possible to prevent the held member from being damaged.

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

  FIG. 1 shows an exploded configuration of a lens barrel in an imaging apparatus (optical apparatus) such as a video camera or a digital still camera that is Embodiment 1 of the present invention. FIG. 2 shows a cross section of the lens barrel.

  The lens barrel of the present embodiment has an imaging optical system constituted by four lens units L1 to L4. In order from the object side, L1 is a first variable power lens unit, L2 is a second variable power lens unit, and L3 is a third variable power lens unit. These first to third variable power lens units L1 to L3 perform zooming by moving in the optical axis direction of the imaging optical system (hereinafter simply referred to as the optical axis direction). The third variable power lens unit L3 also serves as a correction lens (anti-vibration element) that optically reduces image blur by shifting in a direction orthogonal to the optical axis of the imaging optical system. . In the following description, the third variable power lens unit L3 is referred to as a correction lens. L4 is a focus lens unit that corrects movement of the focal plane accompanying zooming and adjusts the focus by moving in the optical axis direction.

  Reference numeral 10 denotes a first lens barrel that holds the first variable magnification lens unit L1, reference numeral 40 denotes a second lens barrel that holds the second variable magnification lens unit L2, and reference numeral 50 denotes an aperture unit that adjusts the amount of light. Reference numeral 60 denotes a vibration isolation unit that shifts the correction lens L3 in a direction orthogonal to the optical axis of the imaging optical system. Reference numeral 20 denotes a zoom cam ring (lens barrel member) in which cams (cam groove portions) for moving the first and second lens barrels 10 and 40, the aperture unit 50, and the image stabilizing unit 60 in the optical axis direction are formed. In FIG. 1, reference numeral 21 is attached to a cam groove portion for moving the image stabilization unit 60 in the optical axis direction.

  Reference numeral 90 denotes a focus driving unit that moves the focus lens unit L4 in the optical axis direction.

  Reference numeral 130 denotes a zoom operation ring. By rotating the zoom operation ring 130 by manual operation, the zoom cam ring 20 is rotated, and the first and second lens barrels 10 and 40, the aperture unit 50, and the image stabilization unit 60 are turned on. Move in the axial direction. Reference numeral 30 denotes a fixed cylinder, which is disposed on the inner periphery of the zoom cam ring 20 and accommodates the first and second lens barrels 10 and 40, the aperture unit 50, and the image stabilization unit 60. The fixed cylinder 30 is formed with a rectilinear guide groove that extends in the optical axis direction and prevents the first and second lens barrels 10 and 40, the aperture unit 50, and the vibration isolation unit 60 from rotating around the optical axis. In FIG. 1, reference numeral 31 is given to the straight guide groove for the vibration isolation unit 60.

  Reference numeral 70 denotes an intermediate lens barrel, which holds the focus drive unit 90. Reference numeral 100 denotes a rear barrel coupled to the fixed barrel 30 via the intermediate barrel 70. In the focus driving unit 90, the focus lens unit L4 is driven in the optical axis direction by the driving force from the focus motor 80. The intermediate lens barrel 70 and the rear lens barrel 100 support both ends of a guide shaft (not shown) that guides the focus lens unit L4 in the optical axis direction.

  The rear lens barrel 100 holds an image sensor (see FIG. 7) such as a CCD sensor or a CMOS sensor. The image sensor photoelectrically converts a subject image formed by the imaging optical system.

  Reference numeral 120 denotes a coupling barrel for coupling the lens barrel to the imaging apparatus main body, and is fixed to the fixed barrel 30 together with the intermediate barrel 70.

  Next, the image stabilization unit 60 will be described with reference to FIGS. 3 and 4. FIG. 3 shows the structure of the image stabilization unit 60 in an exploded manner. 4 shows a cross section of the image stabilizing unit 60, the zoom cam ring 20, and the fixed cylinder 30 when cut along the line AA in FIG.

  In FIG. 3, reference numeral 101 denotes a shift lens barrel as a holding member that holds the correction lens L3. A shift base 102 holds the shift barrel 101 so as to be shiftable in a direction orthogonal to the optical axis of the imaging optical system (or the optical axis of the correction lens L3) (hereinafter referred to as the optical axis orthogonal direction). It is. Reference numeral 103 denotes a sensor base that is positioned with respect to the shift base 102 and fixed by screws 112. The shift base 102 and the sensor base 103 constitute a base member.

  A magnet unit 104p is a part of the magnetic circuit, and is fixed to the shift base 102 by adhesion. As shown in FIG. 2, the magnet unit 104p includes a drive magnet 104m and a yoke 104n attracted to the drive magnet 104m. Half of the drive magnet 104m in the direction perpendicular to the optical axis (vertical direction) is magnetized so that the S pole and the N pole are formed on opposite sides in the optical axis direction.

  Reference numeral 105p denotes a drive coil fixed to the shift barrel 101 by adhesion, and is arranged to face two magnetic poles (S pole and N pole) formed above and below the drive magnet 104m. Reference numeral 106 denotes an upper yoke that constitutes a part of the magnetic circuit, and is disposed on the side opposite to the drive magnet 104m with respect to the drive coil 105p.

  When the drive coil 105p is energized, the gap magnetic flux in the magnetic circuit and the magnetic flux generated by the drive coil 105p magnetically interfere to generate a so-called Lorentz force. A driving force (thrust force) is applied to the shift barrel 101 by the Lorentz force, and the shift barrel 101 is driven in the pitch direction which is the vertical direction in the direction perpendicular to the optical axis.

  Thus, the magnet unit 104p (the yoke 104n and the drive magnet 104m), the drive coil 105p, and the yoke 106 constitute a first actuator that shifts the shift barrel 101 in the pitch direction (first direction).

  Note that the subscript p of each symbol indicates a component for driving the correction lens L3 in the pitch direction to reduce image blur in the pitch direction.

  On the other hand, a component y for driving the correction lens L3 in the yaw direction (horizontal direction in the direction orthogonal to the optical axis) to reduce image blur in the yaw direction is denoted by the suffix y. That is, the magnet unit 104y, the drive coil 105y, and the yoke 106 constitute a second actuator that shifts the shift barrel 101 in the yaw direction (second direction).

  Here, with respect to the optical axis orthogonal direction, which is the moving direction of the shift barrel 101 and other members, “orthogonal” means that it is completely orthogonal to the optical axis, as well as within the allowable error range. (When considered orthogonal).

  The first actuator and the second actuator are arranged so that their phases are different from each other by 90 degrees around the optical axis position when viewed in the optical axis direction.

  In this embodiment, a so-called moving magnet type vibration isolation unit 60 in which a drive magnet is provided in the shift barrel 101 and a drive coil is provided in the shift base 102 will be described. However, the present invention can also be applied to a case where a so-called moving coil type anti-vibration unit in which a drive coil is provided in a shift barrel and a drive magnet is provided in a shift base is used. That is, a drive coil may be provided on one of the shift barrel and the shift base, and a drive magnet may be provided on the other.

  Reference numerals 107a, 107b, and 107c are balls (spherical members), and three balls are provided in this embodiment. The balls 107a to 107c may be made of a hard material such as SUS440C or ceramic that has good shape accuracy and surface finish. In particular, ceramic is a non-magnetic material and is not attracted to a magnet, so that it is not adversely affected by surrounding magnetism and is preferable.

  The three balls 107 a to 107 c are disposed in three rectangular recesses (not shown) formed on the shift base 102 and having a flat bottom surface. The inner surface of the recess limits the movement range of the balls 107a to 107c. Further, the balls 107 a to 107 c abut on the flat portions 101 a, 101 b, 101 c formed on the shift barrel 101.

  The shift barrel 101 has an optical axis formed by the bottom surfaces of the three concave portions and the plane portions 101a to 101c by a biasing force from a biasing member (not shown) disposed between the shift barrel 101 and the sensor base 103. Sandwiched in the direction. Thus, the shift barrel 101 is integrated with the shift base 102 in the optical axis direction.

  Each concave portion is moved from the state in which each ball is positioned at the center position to the position of each ball while the shift barrel 101 is moved from the movable center position (the optical axis position of the zoom optical system) to the mechanical maximum movable position. It has a size that allows rolling. Thereby, the shift barrel 101 can move with respect to the shift base 102 while rolling the balls 107a to 107c in a direction orthogonal to the optical axis.

  The mechanical maximum movable amount of the shift barrel 101 is a certain amount between the convex portion 101d arranged in the shift barrel 101 and the flat portion 102d formed on the inner periphery of the shift base 102 in the pitch direction and the yaw direction. It is decided to leave a gap.

  Here, in this embodiment, when the imaging apparatus is powered on, the shift barrel 101 is once driven by the mechanical maximum movable amount or the maximum movable amount in actual use, and then returned to the movable center position. Thus, even if each ball is deviated from the initial position before the image pickup apparatus is turned on, each ball can be moved to the initial position when the image pickup apparatus is turned on. By this ball reset operation, the shift barrel 101 can be guided only by rolling of each ball in all driving directions during actual use (during imaging). In this way, by guiding the shift barrel 101 only by rolling without causing sliding friction of each ball, the drive response of the vibration isolation unit 60 is improved, and the vibration isolation unit 60 has excellent vibration isolation performance. It can be demonstrated.

  In addition, by performing the ball reset operation as appropriate in a state in which no image is taken after the imaging apparatus is turned on, excellent anti-vibration performance can always be obtained during imaging.

  Next, a configuration for detecting the position of the shift barrel 101 in the pitch direction and the yaw direction will be described. In the description here, the subscript p attached to each symbol indicates that it is a component for detecting the position in the pitch direction, and the subscript y is a component for detecting the position in the yaw direction. Indicates that

  In this embodiment, magnetic detection elements 108p and 108y are used as position detectors. The magnetic detection elements 108p and 108y are mounted on a flexible substrate (not shown) and are inserted into holes 103p and 103y provided in the sensor base 103 from the tightening direction of the screws 112 that fix the sensor base 103 to the shift base 102. Fixed. At this time, the magnetic detection elements 108 p and 108 y are positioned in the optical axis direction by the flexible substrate contacting the sensor base 103.

  In the shift barrel 101, position detection magnets (not shown) are fixed at two positions facing the magnetic detection elements 108p and 108y fixed to the sensor base 103 in the optical axis direction. When the position detection magnet facing the magnetic detection element 108p moves in the pitch direction, the output from the magnetic detection element 108p changes. Similarly, when the position detection magnet facing the magnetic detection element 108y moves in the yaw direction, the output from the magnetic detection element 108y changes. Thereby, the position of the shift barrel 101 in the pitch direction and the yaw direction can be detected.

  Note that an optical sensor using a light projecting element such as iRED or a light receiving element such as PSD can also be used as the position detector.

  Three holes 102e, 102f, and 102f for attaching one non-eccentric roller 109e and two eccentric rollers 110f as three members to be held by press-fitting to the outer peripheral portion of the shift base 102 at intervals of 120 degrees. They are formed in the same optical axis orthogonal plane. In the present embodiment, the eccentric roller 109e and the two eccentric rollers 110f are formed of resin.

  In this embodiment, the non-eccentric roller 109e attached to the hole 102e has 90 as the opposite ends of the arrangement phase of the first and second actuators I and II in the shift base 102 as viewed in the optical axis direction shown in FIG. It is provided within the range of degrees D. Within this 90 degree range D, the center of gravity G of the image stabilization unit 60 exists. That is, the non-eccentric roller 109e is provided at a position closer to the center of gravity G of the image stabilizing unit 60 as compared to the eccentric roller 110h. The reason for this will be described later.

  5 and 6 show the eccentric roller 109e and the eccentric roller 110f as viewed from the direction of the arrow B and the direction of the arrow C in FIG. 4, respectively.

  As shown in FIG. 4, the non-eccentric roller 109 e includes a guide portion 109 i that engages with a press-fit portion 109 j that is press-fitted into a hole portion 102 e formed in the shift base 102 and a rectilinear guide groove 31 formed in the fixed cylinder 30. And have. Further, the non-eccentric roller 109e has a hollow cylindrical cam follower portion (non-eccentric portion) 109h that engages with a cam groove portion 21 as an engaging portion formed on the zoom cam ring 20. The press-fit portion 109j, the guide portion 109i, and the cam follower portion 109h are formed coaxially with each other.

  Each eccentric roller 110 f is formed with a press-fit portion 110 j that is press-fitted into the hole 102 f of the shift base 102, and a guide that is formed coaxially with the central axis of the press-fit portion 110 j and that engages with the rectilinear guide groove 31 of the fixed cylinder 30. Part 110i. Further, each eccentric roller 110f has a hollow cylindrical shape that is eccentric in the radial direction with respect to the central axis of the press-fit portion 110j and the guide portion 110i, and an eccentric cam follower portion that engages with a cam groove portion 21 formed in the zoom cam ring 20. (Eccentric part) 110h.

  As shown in FIG. 6, a recess 110g is formed on the inner side of the eccentric cam follower portion 109h of the eccentric roller 110f so that a dedicated tool for adjusting the rotational position around the central axis of the eccentric roller 110f can be engaged. .

  By forming the eccentric roller 110f in the shape described above and changing the rotational position around the central axis, the contact position of the eccentric cam follower portion 109h with the cam surface of the cam groove portion 21 changes. . As a result, the amount of inclination of the shift base 102 with the eccentric roller 110f attached to the zoom cam ring 20 changes. As described above, the shift barrel 101 is integrated with the shift base 102 in the optical axis direction. For this reason, when the inclination amount of the shift base 102 changes, the inclination amount of the shift barrel 101, that is, the whole image stabilization unit 60 also changes. That is, by adjusting the rotational position of the eccentric roller 110f, the inclination of the optical axis of the correction lens L3 held by the shift barrel 101 with respect to the optical axis of the imaging optical system can be adjusted.

  As described above, the guide portion 110i of the eccentric roller 110f is formed coaxially with the central axis of the eccentric roller 110f. For this reason, even if the eccentric roller 110f is rotated about the central axis, no force is generated between the guide portion 110i and the rectilinear guide groove portion 31 to displace the shift base 102 in the direction perpendicular to the optical axis. Therefore, it is possible to adjust the inclination of the correction lens L3 by adjusting the rotational position of the eccentric roller 110f, while avoiding that accurate optical adjustment is hindered by the parallel eccentricity of the correction lens L3 in the direction perpendicular to the optical axis.

  Next, a method for adjusting the inclination of the correction lens L3 will be described. First, centering adjustment is performed with the vibration isolation unit 60 alone. Specifically, for example, the image stabilization unit 60 is attached to an adjustment tool having a dummy optical system corresponding to the imaging optical system, and laser light (parallel light flux) is incident on the optical axis of the dummy optical system. Then, the energization amount to the first and second actuators of the image stabilization unit 60 is changed while monitoring the arrival position of the laser beam on the image plane with a sensor such as a two-dimensional PSD. When the laser light reaches the center of the image plane, the optical axis position of the correction lens L3 coincides with the optical axis position of the dummy optical system. The energization amount to the first and second actuators at this time is set as a reference energization amount.

  Thereafter, the image stabilization unit 60 is attached to the lens barrel, and a predetermined chart is projected on the entire imaging optical system. A reference energization amount is applied to the first and second actuators. Then, the two eccentric rollers 110f are rotated to adjust the inclination of the correction lens L3 so that the center and the four corners of the chart are resolved with good balance.

  When the adjustment of the inclination of the correction lens L3 is completed, the non-eccentric roller 109e and the eccentric roller 110f are fixed with screws 111 inserted through the insides of the hollow cylindrical cam followers 109h and 110h. Note that the press-fitting portion 110j of the eccentric roller 110f is strongly press-fitted into the hole portion 102f formed in the shift base 102 so as not to rotate depending on the tightening torque of the screw 111. For this reason, when the eccentric roller 110f is fixed with the screw 111, the eccentric roller 110f does not rotate and the inclination of the correction lens L3 does not change.

  As described above, according to the present embodiment, by rotating the eccentric roller 110f, it is possible to adjust the inclination of the entire image stabilization unit 60 including the correction lens L3 with respect to the optical axis of the imaging optical system. For this reason, it can be avoided that the distance between the drive coil and the drive magnet constituting each actuator is changed by adjusting the inclination of the correction lens L3, and the thrust generated by each actuator is changed. Similarly, it can be avoided that the position detection accuracy of the correction lens L3 is lowered due to a change in the distance between the magnetic detection element constituting the position detector and the position detection magnet.

  In this embodiment, since the tilt adjustment of the correction lens L3 is performed after the image stabilization unit 60 is assembled to the lens barrel (imaging optical system), the optical performance is deteriorated due to the tilting of other units or the parallel eccentricity. Correction can be performed by adjusting the inclination of the correction lens L3.

  Next, the configuration of an imaging apparatus such as a digital still camera or a video camera on which the lens barrel including the above-described image stabilization unit 60 is mounted will be described with reference to FIG. Note that, here, an image pickup apparatus that is integrally provided with a lens barrel will be described. However, the image stabilization unit 60 can also be mounted on an interchangeable lens apparatus (optical apparatus) that can be attached to and detached from the image pickup apparatus.

  In FIG. 7, reference numeral 150 denotes the lens barrel shown in FIGS. 1 and 2, and includes the image stabilization unit 60.

  The light beam that has passed through the imaging optical system in the lens barrel 150 forms an object image on the imaging element 149 through an optical filter 148 having an infrared cut and optical low-pass function. The subject image is converted into an electrical signal by the image sensor 149.

  The electrical signal a read from the image sensor 149 is converted into an image signal b by the camera signal processing circuit 151.

  Reference numeral 152 denotes a microcomputer serving as a controller that controls the operations (magnification operation, focus operation, and image stabilization operation) of the lens barrel 150.

  The microcomputer 152 monitors the output from the zoom position detection circuit 153 constituted by a conductive pattern (not shown) bonded to the fixed cylinder 30 and a zoom brush (not shown) fixed to the zoom cam ring 20. . When the contact position of the zoom brush on the conductive pattern changes, the signal from the zoom position detection circuit 153 changes. Thereby, the microcomputer 152 detects the zooming state (zoom position) of the imaging optical system.

  Further, the microcomputer 152 outputs from a focus reset circuit 154 configured by a photo interrupter (not shown) fixed to the intermediate lens barrel 70 and a light shielding portion (not shown) provided in the focus driving unit 90. To monitor. When the focus lens unit L4 is positioned at the reference position, the light shielding unit enters between the light projecting unit and the light receiving unit of the photo interrupter, and the signal from the light receiving unit changes. Thereby, the microcomputer 152 detects that the focus lens unit L4 is located at the reference position. By counting the number of drive pulses input to the focus drive unit 90 from the reference position, the position of the focus lens unit L4 can be detected.

  The microcomputer 152 generates contrast information (high frequency component) from the video signal b from the camera signal processing circuit 151. Then, the focus drive unit 90 is operated through the focus drive circuit 155 so as to move the focus lens unit L4 to a position where the contrast is maximized. Thereby, focus adjustment is performed.

  The microcomputer 152 operates the focus drive unit 90 via the focus drive circuit 155 according to the signal from the zoom position detection circuit 153, and moves the focus lens unit L4 so as to maintain a predetermined positional relationship with respect to the zoom position. Move. As a result, the zooming operation can be performed while maintaining the in-focus state.

  Further, the microcomputer 152 generates brightness information from the video signal b from the camera signal processing circuit 151. Then, the aperture unit 50 is operated through the exposure control drive circuit 156 based on the brightness information. Thereby, the brightness of the subject image formed on the image sensor 149 can be controlled.

  Reference numerals 157 and 158 denote pitch and yaw coils for controlling energization to the first and second actuators (drive coils 105p and 105y) described above in order to shift the shift barrel 101 of the image stabilization unit 60 in the pitch direction and the yaw direction. It is a drive circuit.

  Reference numerals 159 and 160 denote pitch and yaw position detection circuits including magnetic detection elements 108p and 108y for detecting the shift position of the shift barrel 101 in the pitch direction and the yaw direction. Outputs from the position detection circuits 159 and 160 are input to the microcomputer 152. In this embodiment, the pitch direction and the yaw direction, which are the driving force generation directions by the first and second actuators, are matched with the position detection directions by the position detection circuits 159 and 160, but they are different. May be.

  Reference numerals 161 and 162 denote pitch and yaw angle detection circuits for detecting a shake angle in the pitch direction and the yaw direction of the imaging apparatus. The angle detection circuits 161 and 162 include an angular velocity sensor such as a vibration gyro, and an integration circuit that integrates the output of the angular velocity sensor. The output from the integration circuit is input to the microcomputer 152 as an angular displacement signal (a shake signal).

  The microcomputer 152 outputs control signals to the pitch and yaw coil drive circuits 157 and 158 based on the angular displacement signals in the pitch direction and the yaw direction. The pitch and yaw coil drive circuits 157 and 158 apply energization amounts corresponding to the control signals to the first and second actuators (drive coils 105p and 105y). Thereby, the shift barrel 101 is shifted with respect to the optical axis of the imaging optical system, the light beam passing through the correction lens L3 is bent, and the subject image formed on the imaging element 149 moves. Specifically, the first and second objects are formed such that the subject image formed on the image sensor 149 moves in the direction opposite to the original movement direction due to the shake of the image pickup apparatus and by the same amount as the original movement amount. The energization amount to the second actuator is controlled. In this way, image blur due to camera shake is reduced.

  The microcomputer 152 subtracts the shift position of the shift barrel 101 obtained by the position detection circuits 159 and 160 from the angular displacement obtained by the angle detection circuits 161 and 162. Then, the energization to the drive coils 105p and 105y is feedback-controlled through the coil drive circuits 157 and 158 so that the difference becomes small. As a result, the shift amount of the shift barrel 101 can be accurately controlled, and high vibration isolation performance can be obtained.

  As shown in FIGS. 4 and 5, the eccentric roller 109e and the eccentric roller 110f in this embodiment both have cam followers 109h and 110h formed in a hollow cylindrical shape. Of these, the eccentric cam follower portion 110h of the eccentric roller 110f is thinner than the cam follower portion 109h of the eccentric roller 109e. That is, the eccentric cam follower portion 110h of the eccentric roller 110f is lower in strength than the cam follower portion 109h of the non-eccentric roller 109e.

  On the other hand, a roller provided within a 90-degree range D (that is, near the center of gravity G of the vibration isolation unit) having the arrangement phases of the first and second actuators at both ends is caused by another drop of the imaging device. More susceptible to greater impact.

  For this reason, in this embodiment, an eccentric roller 109e having a strength higher than that of the eccentric roller 110f is provided near the center of gravity G of the vibration isolation unit. As a result, the eccentric roller 109e is not deformed or damaged even when it is subjected to an impact caused by dropping or the like of the imaging device, and the function of the image stabilizing unit 60 is protected.

  FIG. 8 shows a second embodiment of the present invention. FIG. 8 is a view showing the non-eccentric roller 109e as seen from the outer peripheral side of the lens barrel.

  The present embodiment is different from the first embodiment in that the non-eccentric roller 109e is formed of metal. Since the other configuration is the same as that of the first embodiment, the same reference numerals as those of the first embodiment are given to components common to the first embodiment in FIG.

  As described in the first embodiment, the non-eccentric roller 109e provided in the range D of 90 degrees having the arrangement phases of the first and second actuators at both ends (that is, near the center of gravity G of the vibration isolation unit) Due to the fall of the imaging device or the like, it is more susceptible to a larger impact than the other eccentric roller 110f.

  For this reason, in this embodiment, the eccentric roller 109e is made of metal, so that the strength of the eccentric roller 109e is higher than that in the first embodiment. In other words, the strength of the eccentric roller 109e, which is originally higher in strength than the eccentric roller 110f, is further increased. Thereby, the possibility that the eccentric roller 109e is deformed or damaged due to an impact caused by dropping of the imaging device or the like can be made lower than that in the first embodiment.

  In addition, it is also possible to arrange the eccentric roller 110f within the 90-degree range D in place of the non-eccentric roller 109e by forming the eccentric roller 110f from metal.

  FIG. 9 shows a third embodiment of the present invention. FIG. 9 is a view showing the non-eccentric roller 109e as seen from the outer peripheral side of the lens barrel. The present embodiment is different from the second embodiment in that the non-eccentric roller 109e is formed of resin. Since the other configuration is the same as that of the first embodiment, the same reference numerals as those of the first embodiment are given to components common to the first embodiment in FIG.

  As described in the first embodiment, the non-eccentric roller 109e provided in the range D of 90 degrees having the arrangement phases of the first and second actuators at both ends (that is, near the center of gravity G of the vibration isolation unit) Due to the fall of the imaging device or the like, it is more susceptible to a larger impact than the other eccentric roller 110f.

  Therefore, in this embodiment, the following condition is satisfied after the eccentric roller 109e is formed of resin.

d × MPa ≧ 60
However, d is the minimum thickness of the cam follower part 109h which is a hollow cylindrical part, and MPa is the bending strength of this resin. By satisfying this condition, the strength of the eccentric roller 109e, which is originally higher in strength than the eccentric roller 110f, is further increased.

  Thereby, the possibility that the eccentric roller 109e is deformed or damaged due to an impact caused by dropping of the imaging device or the like can be made lower than that in the first embodiment.

  In addition, by forming the eccentric roller 110f so as to satisfy the above conditions, the eccentric roller 110f can be disposed within the 90-degree range D instead of the non-eccentric roller 109e.

  Each embodiment described above is only a representative example, and various modifications and changes can be made to each embodiment in carrying out the present invention.

  For example, in each of the embodiments described above, the case where the correction lens is used as the image stabilization element has been described. Therefore, the present invention can also be applied to reduce image blur.

1 is an exploded perspective view showing a configuration of a lens barrel mounted on an imaging apparatus that is Embodiment 1 of the present invention. FIG. 3 is a cross-sectional view illustrating a configuration of a lens barrel of Embodiment 1. FIG. 3 is an exploded perspective view illustrating a configuration of a vibration isolation unit mounted on the lens barrel of the first embodiment. Sectional drawing of the lens-barrel cut | disconnected along the AA line of FIG. The figure which looked at the lens-barrel of FIG. 4 from the arrow B direction. The figure which looked at the lens-barrel of FIG. 4 from the arrow C direction. FIG. 2 is a block diagram illustrating an electrical configuration of the imaging apparatus according to the first embodiment. The figure which looked at the lens barrel of the imaging device which is Example 2 of this invention from the outer peripheral side. The figure which looked at the lens barrel of the imaging device which is Example 3 of this invention from the outer peripheral side.

Explanation of symbols

L1, L2 Variable magnification lens unit L3 Correction lens L4 Focus lens unit 10 First barrel 20 Zoom cam ring 30 Fixed barrel 40 Second barrel 50 Aperture unit 60 Anti-vibration unit 70 Intermediate barrel 80 Focus motor 90 Focus drive unit 101 Shift Lens barrel 102 Shift base 103 Sensor base 104m Driving magnet 104n, 106 Yoke 104p, 104y Magnet unit 105p, 105y Driving coil 107a-107c Ball 108p, 108y Magnetic detection element 109e Uneccentric roller 110f Eccentric roller 120 Rear lens barrel 130 Zoom operation ring

Claims (5)

A holding member that holds the vibration isolating element, a base member that holds the holding member so as to be shiftable with respect to the optical axis of the optical system, a coil provided on one of the holding member and the base member, and a coil provided on the other An anti-vibration unit including a first actuator and a second actuator, each of which includes a first actuator that shifts the holding member in two different directions with respect to the optical axis.
A lens barrel member that holds the vibration isolation unit;
The anti-vibration unit is held by the lens barrel member by engaging three held members provided on the base member with an engagement portion formed on the lens barrel member,
Of the three members to be held, two members to be held have eccentric portions that are eccentric with respect to the central axis of the members to be held, and the eccentric portions are engaged with the engaging portions. Optical equipment. The first and second actuators are arranged so that the phases are 90 degrees different from each other when viewed in the optical axis direction.
The eccentric portion of the two held members and the non-eccentric portion that engages with the engaging portion of the other held member have a hollow cylindrical shape,
The held member having the non-eccentric part is provided in a range of 90 degrees with the arrangement phases of the first and second actuators as both ends of the base member as viewed in the optical axis direction. The optical apparatus according to claim 1. A holding member that holds the vibration isolation element, a base member that holds the holding member so as to be shiftable with respect to the optical axis of the optical system, and a first member that shifts the holding member in two different directions with respect to the optical axis. An anti-vibration unit including the actuator and the second actuator;
A lens barrel member that holds the vibration isolation unit;
The anti-vibration unit is held by the lens barrel member by engaging three held members provided on the base member with an engagement portion formed on the lens barrel member,
The first and second actuators are arranged so that the phases are 90 degrees different from each other when viewed in the optical axis direction.
Of the three members to be held, one member to be held is provided within a range of 90 degrees with the arrangement phases of the first and second actuators as both ends of the base member as viewed in the optical axis direction. And
The one held member has higher strength than the other two held members among the three held members.   The optical apparatus according to claim 3, wherein the one member to be held is made of metal. The optical apparatus according to claim 3, wherein the one member to be held is formed of a resin and satisfies the following condition.
d × MPa ≧ 60
Here, d is the thickness of the hollow cylindrical portion that engages with the engaging portion of the one held member, and MPa is the bending strength of the resin.