Lens apparatus

Abstract

To provide a lens device capable of suppressing backlash of a lens and improving accuracy of detection of a lens position.SOLUTION: The lens barrel includes a focus lens 11, a lens frame 12 that holds the focus lens 11 and is movable along an optical path O, a main shaft 13 and a sub-shaft 14 that guide the movement of the lens frame 12, a VCM15 and a VCM16 that apply a driving force to the lens frame 12, a fixed frame 17 that fixes the main shaft 13, the sub-shaft 14, the VCM15, and the VCM16, and a position sensor 18 that detects the position of the lens frame 12. When the lens device 1 is divided into a first region and a second region, the main shaft 13 and the VCM15 part are arranged in the first region, the sub-shaft 14 and the VCM16 part are arranged in the second region, the VCM15 part and the VCM16 part are arranged across the optical axis O, and the position sensor 18 is arranged between the main shaft 13 and the sub-shaft 14 in a direction different from the lateral direction.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a lens device. [Background technology]

[0002] Patent document 1 describes a lens barrel in which the focus lens and zoom lens are configured to be movable in the optical axis direction, the lens support frame that holds the focus lens is supported so as to be movable in the optical axis direction by a suspension shaft and a rotation stop shaft fixed to the fixed barrel, and is driven by a pair of voice coil motors arranged opposite each other, and a position detection sensor for detecting the position of the lens support frame is fixed near the suspension shaft on the outer periphery of the lens support frame via a shield plate member.

[0003] Patent document 2 describes a lens barrel comprising a first movable lens frame body to which a first movable lens group is attached, and a second movable lens frame body to which a second movable lens group is attached, both of which are slidable in the optical axis direction; the first movable lens frame body is slidably supported on a pair of guide shafts and driven by a pair of voice coil motors arranged opposite each other, with an elastic buffer material provided at the rear; and the second movable lens frame body is slidably supported on a pair of guide shafts and driven by a pair of voice coil motors arranged opposite each other.

[0004] Patent Document 3 describes a lens drive unit that includes an A-group lens unit having an A-group lens, an A-group lens frame (first moving frame), and an A-group coil, and a B-group lens unit having a B-group lens, a B-group lens frame (second moving frame), and a B-group coil, in which a main axis and a sub-axis that guide the movement of both lens units in the optical axis direction are shared by both lens units and are arranged along the optical axis direction while inserted into the insertion holes of both lens units, and both lens units are driven by a pair of voice coil motors that are arranged opposite each other and include a field unit, an A-group coil, and a B-group coil. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-156283 [Patent Document 2] Japanese Patent Application Publication No. 2019-109427 [Patent Document 3] Japanese Patent Application Publication No. 2023-129928 Summary of the Invention

[0006] One embodiment of the technique of the present disclosure provides a lens device that can suppress lens wobble and improve the accuracy of lens position detection. [Means for solving the problem]

[0007] (1) Lenses and a lens frame that holds the lens and is movable along an optical axis; a first axis and a second axis that guide the movement; a first driving unit and a second driving unit that apply a driving force to the lens frame; a fixed frame that fixes the first shaft, the second shaft, the first driving unit, and the second driving unit; a position sensor for detecting the position of the lens frame; When the device is divided into a first area and a second area on a plane in the first direction including the optical axis, the first shaft and the first drive unit are disposed in the first region, the second shaft and the second drive unit are disposed in the second region, In a direction intersecting the first direction, the position sensor is disposed between the first axis and the second axis. Lens device.

[0008] (2) The lens device according to (1), The first driving unit and the second driving unit are arranged opposite each other across the optical axis. Lens device.

[0009] (3) The lens device according to (2), The opposing faces are parallel. Lens device.

[0010] (4) The lens device according to any one of (1) to (3), The position sensor is a magnetic sensor. Lens device.

[0011] (5) The lens device according to any one of (1) to (4), When viewed in the direction of the optical axis, the distance of the position sensor from the optical axis is shorter than the distance of the farthest part of the first axis from the optical axis. Lens device.

[0012] (6) The lens device according to any one of (1) to (5), The lens frame includes an impact absorbing portion that absorbs impact when the lens frame collides with the fixed frame. Lens device.

[0013] (7) The lens device according to any one of (1) to (6), the lens frame has a convex portion that absorbs impact when colliding with the fixed frame; The lens device according to (1).

[0014] (8) The lens device according to any one of (1) to (7), the lens frame is a resin part having a first side surface having a first axis portion on which the first axis is arranged and a first portion different from the first axis portion, and a second side surface having a second axis portion on which the second axis is arranged and a second portion different from the second axis portion, a direction of the first shaft portion and the opening of the first portion is a second direction; The direction of the second shaft portion and the opening of the second portion is a third direction different from the second direction. Lens device.

[0015] (9) The lens device according to any one of (1) to (8), an optical adjustment mechanism capable of adjusting the optical axis of the lens; Lens device.

[0016] (10) The lens device according to any one of (1) to (9), Used in the first and second positions, Looking in the direction of the optical axis, a direction of a straight line passing through the first axis and the center of gravity of a movable member including the lens and the lens frame is different from a direction of gravity in the first posture and a direction of gravity in the second posture; Lens device.

[0017] (11) The lens device according to (10), The second attitude is an attitude obtained by rotating the first attitude by 90° around the optical axis. Lens device.

[0018] (12) The lens device according to (10) or (11), a direction of a straight line passing through the second axis and the optical axis is different from a direction of gravity in the first attitude and a direction of gravity in the second attitude; Lens device.

[0019] (13) A lens device according to any one of (1) to (12), Used in the first and second positions, The first direction is a direction along the horizontal in the first attitude. Lens device.

[0020] (14) Lenses and a lens frame that holds the lens and is movable along an optical axis; a first axis and a second axis that guide the movement; a first driving unit and a second driving unit that apply a driving force to the lens frame; a fixed frame that fixes the first shaft, the second shaft, the first driving unit, and the second driving unit; a position sensor for detecting the position of the lens frame; When the device is divided into a first area and a second area on a plane in the first direction including the optical axis, the first shaft and the first drive unit are disposed in the first region, the second shaft and the second drive unit are disposed in the second region, Used in the first and second positions, Looking in the direction of the optical axis, a direction of a straight line passing through the first axis and the center of gravity of a movable member including the lens and the lens frame is different from a direction of gravity in the first posture and a direction of gravity in the second posture; Lens device. [Effects of the Invention]

[0021] According to the present invention, it is possible to provide a lens device that can suppress lens wobble and improve the accuracy of lens position detection. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 is a perspective view showing an example of a lens device 1 of the present embodiment as viewed from the left front direction. [Figure 2] FIG. 2 is a side view of the lens device 1 shown in FIG. 1, viewed from the left. [Figure 3] 3 is a cross-sectional view of the lens device 1 shown in FIG. 2 taken along line AA. [Figure 4] FIG. 2 is a diagram showing a first example of arrangement of the position sensor 18. [Figure 5] FIG. 10 is a diagram showing a second example of the arrangement of the position sensor 18. [Figure 6] 10 is a diagram showing the direction of the openings of the main bearing portion 121 and the sub-bearing portion 122. FIG. [Figure 7]1 is a diagram showing the orientation of a main shaft 13 and a sub-shaft 14 in a lens device 1 attached to an imaging device in a landscape orientation. [Figure 8] 1 is a diagram showing the orientation of a main shaft 13 and a sub-shaft 14 in a lens device 1 attached to an imaging device in a vertical shooting position. [Figure 9] 3 is a cross-sectional view of the lens device 1 shown in FIG. 2 taken along line BB. [Figure 10] FIG. 2 is a perspective view of the lens frame 12 as seen from the rear side. [Figure 11] FIG. 2 is a rear view of the lens frame 12. [Figure 12] FIG. 2 is a front view of the lens frame 12. DETAILED DESCRIPTION OF THE INVENTION

[0023] An example of an embodiment of the present invention will be described below with reference to the drawings. In this embodiment, the terms "upward," "downward," "leftward," "rightward," "forward," and "rearward" are used, but these directions are relative directions set for the lens device shown in each drawing for the sake of convenience.

[0024] <Lens device according to an embodiment> Fig. 1 is a perspective view showing an example of a lens device 1 of this embodiment as seen from the front left. Fig. 2 is a side view of the lens device 1 shown in Fig. 1 as seen from the left. The lens device 1 is applicable to, for example, consumer video cameras, ENG (Electronic News Gathering) cameras for television broadcasting, surveillance cameras, etc.

[0025] As shown in Figures 1 and 2, lens device 1 is configured in a generally cylindrical shape overall. Lens device 1 includes a lens barrel 2 that houses an optical system. When the side into which light from a subject image is incident in the direction of optical axis O is defined as the front, lens barrel 2 has a zoom optical unit 3 located on the front side and a focus optical unit 4 located on the rear side. The optical systems housed in lens barrel 2 include a zoom optical system having a zoom lens or a group of zoom lenses housed in zoom optical unit 3, and a focus optical system having a focus lens or a group of focus lenses housed in focus optical unit 4. Lens device 1 is a rear-focus type lens device with a variable focal length.

[0026] A mount ring 4a for coupling with an imaging device (not shown, for example, an ENG camera for television broadcasting) is provided at the rear of the focus optical unit 4. The lens device 1 is attached to a camera body of an interchangeable lens type via the mount ring 4a.

[0027] Additionally, on the outer periphery of the lens barrel 2, a focus ring 5 for adjusting the focus and a zoom ring 6 for changing the zoom magnification are each rotatably provided.

[0028] Additionally, an operating unit 7 is provided on the outer periphery of the focus optical unit 4, and includes a sliding macro ON / OFF switch 7a, an AF / MF selector switch 7b, and a non-locking AF push switch 7c. The macro ON / OFF switch 7a switches the macro shooting mode on and off. The AF / MF selector switch 7b switches between autofocus (AF) mode and manual focus (MF) mode. The AF mode is a mode in which the focus lens is automatically moved to maximize the contrast of the subject image, thereby adjusting the focus. The MF mode is a mode in which the focus lens is moved by manually rotating the focus ring 5, thereby adjusting the focus. The AF push switch 7c switches the mode to AF mode only while its key top is pressed when the AF / MF selector switch 7b has switched the mode to MF mode. Output signals generated by the operation of these switches are transmitted via signal lines to the drive units that drive the various components.

[0029] Fig. 3 is a cross-sectional view of the lens device 1 taken along line AA shown in Fig. 2. As shown in Fig. 3, when the inside of the focus optical unit 4 is viewed from the rear side of the lens device 1 in the direction of the optical axis O, the focus optical unit 4 contains a focus lens 11 and a lens frame 12 that holds the focus lens 11.

[0030] The focus lens 11 is a lens that changes the focal position of the optical system. The focus lens 11 is held in the center of the focus optical unit 4 by a lens frame 12. The lens frame 12 is a resin part made of, for example, synthetic resin. The lens frame 12 is configured to be movable along the optical axis O of the focus lens 11. Therefore, the focus lens 11 held by the lens frame 12 is configured to be movable along the optical axis O together with the lens frame 12 as the lens frame 12 moves. "Movement along the optical axis O" means movement in a direction parallel to the optical axis O.

[0031] Also provided within the focus optical unit 4 are a main shaft 13 and a sub-shaft 14 that guide the movement of the lens frame 12, and a first voice coil motor (first VCM) 15 and a second voice coil motor (second VCM) 16 that apply driving force to the lens frame 12. The main shaft 13 is an example of the "first shaft" in the present invention. The sub-shaft 14 is an example of the "second shaft" in the present invention. The first VCM 15 is an example of the "first driving unit" in the present invention. The second VCM 16 is an example of the "second driving unit" in the present invention.

[0032] The main shaft 13 and the sub-shaft 14 are arranged parallel to the optical axis O of the focus lens 11. The main shaft 13 is a guide shaft that serves as a reference for movement of the lens frame 12 in the direction of the optical axis O. The sub-shaft 14 is a guide shaft that restricts rotation of the lens frame 12. The main shaft 13 is inserted into a main bearing portion 121 formed in the lens frame 12. The sub-shaft 14 is inserted into a sub-bearing portion 122 formed in the lens frame 12. The main shaft 13 and the sub-shaft 14 guide the lens frame 12, which holds the focus lens 11, along the optical axis O of the focus lens 11 while restricting its rotation. The main bearing portion 121 is an example of a "first shaft portion" in the present invention. The sub-bearing portion 122 is an example of a "second shaft portion" in the present invention. The main bearing portion 121 and the sub-bearing portion 122 will be described further below with reference to FIG. 10 .

[0033] The first VCM 15 and the second VCM 16 are rectangular parallelepiped motors each consisting of a yoke with a magnet and a voice coil. The driving forces of the first VCM 15 and the second VCM 16 are for moving the lens frame 12 holding the focus lens 11 and for maintaining the position of the lens frame 12 after it has moved.

[0034] Furthermore, a fixed frame 17 that fixes the main shaft 13, the sub-shaft 14, the first VCM 15, and the second VCM 16 is provided within the focus optical unit 4. The fixed frame 17 is attached to a housing that constitutes the focus optical unit 4. The yoke of the first VCM 15 and the yoke of the second VCM 16 are each fixed to the fixed frame 17. The voice coil of the first VCM 15 and the voice coil of the second VCM 16 are each fixed to the lens frame 12. The lens frame 12 is provided with impact absorbing portions 131 to 134 that absorb impact due to a collision with the fixed frame 17. The impact absorbing portions 131 to 134 will be described later with reference to FIG. 10.

[0035] A position sensor 18 that detects the position of the lens frame 12 is also provided within the focus optical unit 4. The "position of the lens frame 12" refers to the position of the lens frame 12 in the direction of the optical axis O. The position sensor 18 is a magnetic sensor that includes, for example, a magnetic scale on which north and south poles are magnetized at a predetermined pitch, and an MR (Magnetic Resonance) sensor that detects the north and south poles of the magnetic scale. The magnetic scale is attached to a magnet receiving portion 123 formed on the lens frame 12. The MR sensor is attached to the fixed frame 17.

[0036] Here, let us assume that the cross-sectional area of ​​the lens device 1 (the device itself) shown in FIG. 3 is divided into a first area above the plane P1 and a second area below the plane P1 by, for example, a plane P1 in the horizontal direction including the optical axis O. The horizontal direction is an example of the "first direction" in the present invention. The horizontal direction is the direction that is horizontal when the lens device 1 is attached to an imaging device (camera) and the imaging device is in a standard position. The standard position refers to, for example, the landscape position of the imaging device, which is in a landscape or portrait position. The cross-section of the lens device 1 shown in FIG. 3 is when the lens device 1 is attached to an imaging device in a landscape position. In this case, the main shaft 13 and the first VCM 15 are located in the first area above the plane P1. The sub-shaft 14 and the second VCM 16 are located in the second area below the plane P1.

[0037] The first VCM 15 and the second VCM 16 are arranged opposite each other with the optical axis O in between. "Arranged opposite the optical axis O" means that they are provided in positions symmetrical with respect to the optical axis O (for example, symmetrical with respect to a horizontal plane P1 including the optical axis O) when viewed in the direction of the optical axis O. "Arranged opposite each other" means that they are arranged in parallel, and for example, one face of each of the first VCM 15 and second VCM 16, which have a rectangular parallelepiped shape as described above, is arranged opposite (parallel to) each other.

[0038] FIG. 4 is a diagram showing a first arrangement example of the position sensor 18. Note that, like FIG. 3, the lens device 1 in FIG. 4 shows a cross section of the lens device 1 taken along line AA. As shown in FIG. 4, the position sensor 18 is arranged between the main shaft 13 and the sub-shaft 14 in a direction different from the horizontal direction including the optical axis O. The "direction different from the horizontal direction" refers to a direction intersecting the horizontal direction, such as a vertical direction. For example, the direction different from the horizontal direction refers to the arrangement direction of the first VCM 15 and the second VCM 16, which is the up-down direction in FIG. 4. Specifically, the position sensor 18 is arranged between a horizontal plane P2 including the main shaft 13 and a horizontal plane P3 including the sub-shaft 14.

[0039] This allows the position sensor 18 to be positioned away from the first VCM 15 and the second VCM 16, making it less susceptible to magnetic influence from the first VCM 15 and the second VCM 16, and allowing the position of the lens frame 12 (the focus lens 11 attached to the lens frame 12) to be accurately detected.

[0040] FIG. 5 is a diagram showing a second example of the arrangement of position sensor 18. Like FIG. 3, lens device 1 in FIG. 5 shows a cross section of lens device 1 taken along line AA. As shown in FIG. 5, when viewed in the direction of optical axis O, the distance from position sensor 18 to optical axis O is shorter than the distance to the farthest part of main shaft 13 from optical axis O. For example, when a circle C (shown by a two-dot chain line) is drawn with optical axis O as its center and the farthest part of main shaft 13 inscribed therein, position sensor 18 is arranged within this circle C. However, position sensor 18 is arranged outside focus lens 11.

[0041] 5, if a horizontal line passing through the optical axis O is drawn, in a configuration (conventional configuration) in which the main shaft 13 is disposed on that line, the position sensor 18 must be disposed outside the main shaft 13 or near the first VCM 15 or the second VCM 16. In contrast, in the case of the present invention, the main shaft 13 is not disposed on a horizontal line passing through the optical axis O, but is disposed in an area above that line. Therefore, the position sensor 18 can be disposed at a distance from the optical axis O that is equal to or close to the distance of the main shaft 13, and away from the first VCM 15 and the second VCM 16. This allows the position sensor 18 to be disposed closer to the center of the lens device 1 than in the conventional configuration, making it possible to reduce the size of the lens device 1.

[0042] Fig. 6 is a diagram showing the direction of the openings of the main bearing portion 121 and the sub-bearing portion 122. Note that, like Fig. 3, the lens device 1 in Fig. 6 shows a cross section of the lens device 1 taken along line AA. Also, the lens device 1 in Fig. 6 shows a cross section when attached to an imaging device in landscape orientation.

[0043] As shown in FIG. 6 , the opening of the main bearing portion 121 of the lens frame 12, through which the main shaft 13 is inserted, faces in the direction indicated by arrow A. In contrast, the opening of the sub-bearing portion 122 of the lens frame 12, through which the sub-shaft 14 is inserted, faces in the direction indicated by arrow B, which is different from the direction indicated by arrow A. As described above, the lens frame 12 is a resin part. A "resin part" is a part molded by heating and melting resin, injecting it into a mold, and then allowing it to cool and solidify. The "direction of the opening" refers to the direction of the die removal mark (the direction in which the mold is removed). For example, in the lens device 1 shown in FIG. 6 , the opening of the main bearing portion 121 faces to the right. Furthermore, in the lens device 1 shown in FIG. 6 , the opening of the sub-bearing portion 122 faces downward and to the left. The direction indicated by arrow A is an example of the "second direction" in the present invention. The direction indicated by arrow B is an example of the "third direction" in the present invention. The openings (recesses) of the main bearing portion 121 and the sub-bearing portion 122 will be described further below with reference to FIG.

[0044] FIG. 7 is a diagram showing the arrangement directions of the main shaft 13 and the sub-shaft 14 in the lens device 1 attached to an imaging device in landscape orientation. Similar to FIG. 3, the lens device 1 in FIG. 7 shows a cross section of the lens device 1 taken along line AA. As shown in FIG. 7, when viewed in the direction of the optical axis O, the direction of a line L1 passing through the main shaft 13 and the center of gravity M of the movable members including the focus lens 11 and the lens frame 12 is different from the direction of gravity (vertical direction). Furthermore, the direction of a line L2 passing through the sub-shaft 14 and the center of gravity M of the movable members including the focus lens 11 and the lens frame 12 is different from the direction of gravity. That is, in the landscape orientation, the directions of the lines L1 and L2 are different from the horizontal direction.

[0045] The landscape orientation is an example of the "first orientation" of the present invention. The "movable member" is an integrated member that includes the lens frame 12 and a member that moves together with the lens frame 12 (for example, the focus lens 11, but there may be other members added). In other words, the movable member is a member that rotates relative to the fixed frame 17 around the main shaft 13 or the sub-shaft 14. In many cases, the "center of gravity M of the movable member" is located at approximately the same position as the optical axis O of the focus lens 11. In the case of the lens device 1 in the landscape orientation shown in FIG. 7, the main shaft 13 is disposed, for example, diagonally upward to the right with respect to the optical axis O. Furthermore, the sub-shaft 14 is disposed, for example, diagonally downward to the left with respect to the optical axis O.

[0046] FIG. 8 is a diagram showing the arrangement directions of the main shaft 13 and the sub-shaft 14 in the lens device 1 attached to an imaging device in a portrait orientation. Similar to FIG. 3, the lens device 1 in FIG. 8 shows a cross section of the lens device 1 taken along line AA. As shown in FIG. 8, when viewed in the direction of the optical axis O, the direction of a line L1 passing through the main shaft 13 and the center of gravity M of the movable members including the focus lens 11 and the lens frame 12 is different from the direction of gravity. Furthermore, the direction of a line L2 passing through the sub-shaft 14 and the center of gravity M of the movable members including the focus lens 11 and the lens frame 12 is different from the direction of gravity. In other words, in a portrait orientation, the directions of the lines L1 and L2 are different from the vertical direction.

[0047] The vertical shooting position is an example of the "second position" of the present invention. The vertical shooting position is a position rotated 90° around the optical axis O from the horizontal shooting position described above in FIG. 7. In this example, the lens is rotated 90° to the left, but it may also be rotated 90° to the right. As described above, the "movable member" refers to a member that rotates relative to the fixed frame 17 around the main shaft 13 or the sub-shaft 14. As described above, the "center of gravity M of the movable member" is located at approximately the same position as the optical axis O. In the case of the lens device 1 in the vertical shooting position shown in FIG. 8, the main shaft 13 is disposed, for example, diagonally upward and to the left with respect to the optical axis O. Furthermore, the sub-shaft 14 is disposed, for example, diagonally downward and to the right with respect to the optical axis O.

[0048] A clearance is provided between the main shaft 13 inserted into the main bearing portion 121 of the lens frame 12 and the inner peripheral surface of the insertion hole of the main bearing portion 121 to allow smooth movement of the lens frame 12. Similarly, a clearance is provided between the sub-shaft 14 inserted into the sub-bearing portion 122 and the inner peripheral surface of the insertion hole. For this reason, the movable members (focus lens 11 and lens frame 12) rotate slightly around the main shaft 13 due to the clearance in the sub-shaft 14, and the movable members (focus lens 11 and lens frame 12) rotate slightly around the sub-shaft 14 due to the clearance in the main shaft 13.

[0049] When viewed in the direction of the optical axis O in the landscape orientation, if the direction of the line L1 passing through the main shaft 13 and the center of gravity M of the movable member is, for example, horizontal, then in the landscape orientation, the direction of rotation of the movable member around the main shaft 13 (the direction of the tangent in the rotation direction) and the direction of gravity coincide. For this reason, the movable member is urged in only one direction (the direction of gravity) by gravity, so that the main shaft 13 and the sub-shaft 14 come into contact with the inner circumferential surfaces of their respective insertion holes in one direction, resulting in stability (no rattle).

[0050] However, if the direction of line L1 passing through main shaft 13 and center of gravity M of the movable member is horizontal in landscape orientation, when the camera is in portrait orientation, the direction of rotation of the movable member around main shaft 13 becomes horizontal. In this case, the movable member can move equally to the left or right in the horizontal direction, and rattle occurs due to movement of main shaft 13 and sub-shaft 14 due to the clearances in their respective insertion holes. The same situation applies to line L2 passing through sub-shaft 14 and center of gravity M of the movable member.

[0051] Furthermore, when viewed in the direction of the optical axis O in the landscape orientation, if the direction of the straight line L1 passing through the main shaft 13 and the center of gravity M of the movable member is, for example, vertical, then, according to the same principle, the camera will be stable in the portrait orientation but will become unstable in the landscape orientation.

[0052] This wobble causes the optical axis of the "lens" in the lens device 1 to deviate from the correct optical axis, resulting in image shaking. For example, if this wobble occurs during focusing, it will result in image shaking during focusing.

[0053] In contrast, in the lens device 1 of the present invention, as described in FIGS. 7 and 8, in both the landscape and portrait orientations, the direction of the line L1 passing through the main shaft 13 and the center of gravity M of the movable member, as viewed along the optical axis O, is different from both the horizontal and the direction of gravity. Therefore, in both the landscape and portrait orientations, the rotation direction of the movable member (the direction of a tangent thereto) and the horizontal do not coincide. As a result, the rotation direction of the movable member (the direction of a tangent thereto) includes a component of the direction of gravity, and the movable member is biased in only one direction by the component of the direction of gravity. Therefore, the main shaft 13 and the sub-shaft 14 inserted into the insertion holes of the movable member are in contact with the inner circumferential surfaces of their respective insertion holes in the direction of gravity, thereby stabilizing the movable member.

[0054] For example, in the landscape shooting position, when the movable member rotates around the main shaft 13, a biasing force is applied to the movable member in the direction of arrow F1 shown in FIG. 7. Furthermore, in the portrait shooting position, when the movable member rotates around the main shaft 13, a biasing force is applied to the movable member in the direction of arrow F2 shown in FIG. 8. The same is true for the line L2 passing through the sub-shaft 14 and the center of gravity M of the movable member. For example, in the landscape shooting position, when the movable member rotates around the sub-shaft 14, a biasing force is applied to the movable member in the direction of arrow F1 shown in FIG. 7. Furthermore, in the portrait shooting position, when the movable member rotates around the sub-shaft 14, a biasing force is applied to the movable member in the direction of arrow F2 shown in FIG. 8. The movable member is biased in only one direction by the weight direction component included in these biasing forces, and is stabilized.

[0055] In this way, the lens device 1 can suppress rattles in the lens frame 12 that holds the focus lens 11, for example, when attached to an imaging device and the imaging device is in a landscape orientation or a portrait orientation, thereby suppressing image shaking caused by rattles and preventing degradation of imaging performance.

[0056] FIG. 9 is a cross-sectional view of the lens device 1 shown in FIG. 2 taken along line BB. As shown in FIG. 9, an optical adjustment mechanism capable of adjusting the optical axis O of the focus lens 11 is provided on the outer periphery of the fixed frame 17. The optical adjustment mechanism includes, for example, three adjustment screws 141, 142, and 143. The adjustment screws 141 to 143 are provided from the outer focus optical unit 4 toward the inner fixed frame 17 so as to abut, for example, against the outer periphery of the fixed frame 17. When the adjustment screws 141 to 143 are tightened, the gap between the outer periphery of the fixed frame 17 with which the adjustment screw abuts and the focus optical unit 4 changes depending on the tightening amount of the adjustment screws. By changing the tightening amount of the adjustment screws 141 to 143, the positional relationship between the focus optical unit 4 and the fixed frame 17 is adjusted, and the optical axis O of the focus lens 11 can be adjusted in any direction. This makes it possible to fine-tune the optical axis O of the focus lens 11 to align it with the optical axes of other optical systems included in the lens device 1.

[0057] <Lens frame configuration> Next, the configuration of the lens frame 12 will be described with reference to Fig. 10 to Fig. 12. Fig. 10 is a perspective view of the lens frame 12 as seen from the rear side. Fig. 11 is a rear view of the lens frame 12. Fig. 12 is a front view of the lens frame 12.

[0058] The lens frame 12 has a circular opening 135 through which the focus lens 11 can be inserted. The lens frame 12 is a generally plate-shaped member. The lens frame 12 has a first side surface on which a main bearing portion 121 on which the main shaft 13 is disposed and a magnet receiving portion 123 and a sensor space 124, which are different from the main bearing portion 121, are provided. The lens frame 12 also has a second side surface on which a sub-bearing portion 122 on which the sub-shaft 14 is disposed and a flexible electronic board installation space 125, which is different from the sub-bearing portion 122, are provided. The "side surface" refers to a surface other than the front and back surfaces of the lens frame 12 and is a surface parallel to the optical axis O. In the lens frame 12 shown in this example, the right side surface is the first side surface, and the left side surface is the second side surface. The magnet receiving portion 123 and the sensor space 124 are an example of the "first portion" of the present invention. The flexible electronic board installation space 125 is an example of the "second portion" of the present invention.

[0059] The main shaft 13 is inserted into an insertion hole 121a of the main bearing 121. The magnetic scale of the position sensor 18 is provided in a groove 123a of the magnet receiving portion 123. The sensor space 124 is a space secured for providing an MR sensor on the fixed frame 17 side opposite the magnetic scale of the magnet receiving portion 123. The sub-shaft 14 is inserted into an insertion hole 122a of the sub-bearing 122. The flexible electronic board installation space 125 is a space secured for installing a flexible electronic board for applying electricity to the first VCM 15 and the second VCM 16.

[0060] As described above, the lens frame 12 is a molded resin part. The opening (cutout mark) of the main bearing portion 121 provided on the first side surface of the lens frame 12, the opening (cutout mark) of the magnet receiving portion 123, and the opening (cutout mark) of the sensor space 124 all face the same direction (toward the right in this example). The opening (cutout mark) of the sub-bearing portion 122 provided on the second side surface of the lens frame 12 and the opening (cutout mark) of the flexible electronic board installation space 125 all face the same direction (toward the lower left in this example) as the openings of the main bearing portion 121, magnet receiving portion 123, and sensor space 124 on the first side surface. The directions of the openings of the main bearing portion 121, magnet receiving portion 123, and sensor space 124 are an example of the "second direction" in this invention. The directions of the openings of the sub-bearing portion 122 and the flexible electronic board installation space 125 are an example of the "third direction" in this invention. In this way, the direction of the opening on the first side surface and the direction of the opening on the second side surface are the same on both sides, so that the lens frame 12 is easy to manufacture.

[0061] As described above, the lens frame 12 is provided with impact absorbing portions 131-134 that absorb the impact of a collision with the fixed frame 17. A "collision with the fixed frame 17" refers to a collision that occurs when the lens frame 12 moves. In particular, when the first VCM 15 and the second VCM 16 that apply driving force to the lens frame 12 are not operating (when not energized), the lens frame 12 moves freely along the main shaft 13 and the sub-shaft 14, causing a collision with the fixed frame 17 that is disposed in front of or behind the lens frame 12. Therefore, in order to absorb the impact of a collision between the lens frame 12 and the fixed frame 17, the lens frame 12 is provided with impact absorbing portions 131-134 that are formed, for example, in a convex shape toward the fixed frame 17. This makes it possible to suppress the impact noise (such as an abnormal clicking noise) that occurs when the lens frame 12 collides with the fixed frame 17.

[0062] In the above example, the focus lens 11 is held by the lens frame 12, but the present invention is not limited to this. For example, the present invention may be applied to a case where a zoom lens that changes the focal length is held by a lens frame. [Explanation of symbols]

[0063] 1 Lens device 2 Telescope tube 3 Zoom optical unit 4 Focusing optics 4a Mounting ring 5 Focus ring 6 Zoom ring 7 Control section 7a Macro ON / OFF switch 7b AF / MF switch 7c AF push switch 11 Focus Lens 12 Lens frame 13 Main shaft 14 Sub-axis 15 1st VCM 16 2nd VCM 17 Fixed Frame 18 Position Sensor 121 Main bearing part 121a, 122a Insertion holes 122 Sub-bearing 123 Magnet receiving part 123a Groove 124 sensor space 125 Flexible electronic board installation space 131~134 Impact absorbing section 135 Opening 141~143 Adjustment screw P1~P3 plane L1,L2 straight line F1,F2 arrows

Claims

1. Lenses and a lens frame that holds the lens and is movable along an optical axis; a first axis and a second axis that guide the movement; a first driving unit and a second driving unit that apply a driving force to the lens frame; a fixed frame that fixes the first shaft, the second shaft, the first driving unit, and the second driving unit; a position sensor for detecting the position of the lens frame; When the device is divided into a first region and a second region on a plane in a first direction including the optical axis, the first shaft and the first drive unit are disposed in the first region, the second shaft and the second drive unit are disposed in the second region, In a direction intersecting the first direction, the position sensor is disposed between the first axis and the second axis. Lens device.

2. 2. The lens device according to claim 1, The first driving unit and the second driving unit are disposed opposite each other across the optical axis. Lens device.

3. 3. The lens device according to claim 2, The opposing sides are parallel. Lens device.

4. 2. The lens device according to claim 1, the position sensor is a magnetic sensor; Lens device.

5. 2. The lens device according to claim 1, When viewed in the direction of the optical axis, the distance of the position sensor from the optical axis is shorter than the distance of the farthest portion of the first axis from the optical axis. Lens device.

6. 2. The lens device according to claim 1, The lens frame includes an impact absorbing portion that absorbs impact when the lens frame collides with the fixed frame. Lens device.

7. 2. The lens device according to claim 1, The lens frame has a convex portion that absorbs impact when colliding with the fixed frame. The lens device according to claim 1 .

8. 2. The lens device according to claim 1, the lens frame is a resin part having: a first side surface having a first axis portion on which the first axis is arranged and a first portion different from the first axis portion; and a second side surface having a second axis portion on which the second axis is arranged and a second portion different from the second axis portion, a direction of the first shaft portion and the opening of the first portion is a second direction; The direction of the second shaft portion and the opening of the second portion is a third direction different from the second direction. Lens device.

9. 2. The lens device according to claim 1, an optical adjustment mechanism capable of adjusting the optical axis of the lens; Lens device.

10. 2. The lens device according to claim 1, Used in the first and second positions, When viewed in the direction of the optical axis, a direction of a straight line passing through the first axis and the center of gravity of a movable member including the lens and the lens frame is different from a direction of gravity in the first posture and a direction of gravity in the second posture; Lens device.

11. 11. The lens device according to claim 10, The second attitude is an attitude obtained by rotating the first attitude by 90° around the optical axis. Lens device.

12. 11. The lens device according to claim 10, a direction of a straight line passing through the second axis and the optical axis is different from a direction of gravity in the first attitude and a direction of gravity in the second attitude; Lens device.

13. 13. The lens device according to claim 1, Used in the first and second positions, the first direction is a direction along the horizontal in the first attitude; Lens device.

14. Lenses and a lens frame that holds the lens and is movable along an optical axis; a first axis and a second axis that guide the movement; a first driving unit and a second driving unit that apply a driving force to the lens frame; a fixed frame that fixes the first shaft, the second shaft, the first driving unit, and the second driving unit; a position sensor for detecting the position of the lens frame; When the device is divided into a first region and a second region on a plane in a first direction including the optical axis, the first shaft and the first drive unit are disposed in the first region, the second shaft and the second drive unit are disposed in the second region, Used in the first and second positions, When viewed in the direction of the optical axis, a direction of a straight line passing through the first axis and the center of gravity of a movable member including the lens and the lens frame is different from a direction of gravity in the first posture and a direction of gravity in the second posture; Lens device.

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