Lens barrel and imaging device

Abstract

To provide a durable lens barrel while maintaining stable biasing in various positions. [Solution] A lens barrel comprising a movable lens group, a movable holding frame for holding the movable lens group, a guide portion for holding the movable holding frame so as to be movable in a direction along the optical axis, and a biasing member for biasing between the movable holding frame and the guide portion, wherein the movable holding frame has a straight guide portion that abuts against the guide portion and is guided along the optical axis direction, and the straight guide portion has a first contact portion and a second contact portion that abuts against the guide portion when viewed from the optical axis direction, and the contact surface of the guide portion that abuts against the first contact portion and the contact surface of the guide portion that abuts against the second contact portion each have curvature, and the curvature of the first contact portion and the second contact portion is smaller than the curvature of the respective contact surfaces of the guide portion.

Description

Technical Field

[0005]

[0001] The present invention relates to a lens barrel and an imaging device.

Background Art

[0002] As the performance of the lens barrel is improved, a structure is required to reduce the deterioration of optical performance caused by the lens tilting or falling in the optical axis direction. In order to suppress changes in tilting in various shooting positions such as the upright position and the vertical position, a structure capable of eliminating play between the lens holding frame and the guide member is known.

[0003] In Patent Document 1, a guide bearing portion is provided in the holding frame of the moving lens, and by inserting a guide member parallel to the optical axis, the moving lens is guided in the optical axis direction. The inner surface of the guide bearing portion has a pair of planes forming a V-groove and is urged against the guide member by an elastic member. Thereby, a structure for suppressing play between the guide bearing portion and the guide member and enabling stable contact at all times is disclosed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In Patent Document 1, the shape of the inner surface of the guide bearing portion is a pair of planes forming a V-shaped groove, and compared with the case of a cylindrical shape, the contact surface pressure with the guide member is increased. Due to the increase in surface pressure, wear of the lens barrel and grease depletion are likely to occur during long-term use, and there is a concern that controllability may deteriorate. On the other hand, when the guide bearing portion is cylindrical, when the posture changes and the gravitational direction changes, or when inertial force occurs during driving of the moving lens, the contact point position with the guide member changes, and stable biasing cannot be achieved.

[0006] Therefore, the present invention aims to provide a durable lens barrel that provides stable biasing in various positions. [Means for solving the problem]

[0007] To achieve the above objective, a lens barrel as one aspect of the present invention comprises a movable lens group, a movable holding frame for holding the movable lens group, a guide portion for holding the movable holding frame so as to be movable in a direction along the optical axis, and a biasing member for biasing the movable holding frame and the guide portion. The movable holding frame is provided with a straight guide portion that abuts against the guide portion and is guided along the optical axis. The straight guide portion has a first contact portion and a second contact portion that abut against the guide portion when viewed from the optical axis direction. The contact surface of the guide portion that abuts against the first contact portion and the contact surface of the guide portion that abuts against the second contact portion each have curvature, and the curvature of the first contact portion and the second contact portion is smaller than the curvature of the respective contact surfaces of the guide portion. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a durable lens barrel that provides stable biasing in various positions. [Brief explanation of the drawing]

[0009] [Figure 1] This is a cross-sectional view of an imaging device consisting of a lens barrel and a camera body according to Embodiment 1. [Figure 2] This is an exploded perspective view of the four-group lens barrel and surrounding components in Embodiment 1. [Figure 3] This is a front view of the configuration in which peripheral members are assembled to the 4-group lens barrel in Embodiment 1. [Figure 4] This is a front view showing the forces acting on the four-group lens barrel in Embodiment 1. [Figure 5] This is an enlarged view of the contact area between the guide member and the straight-line guide in Embodiment 1. [Figure 6]This is a front view showing a modified example of the biasing means and driving means for the guide member of the four-group lens barrel in Embodiment 1. [Figure 7] This is a perspective view of the four-group lens barrel in Embodiment 2. [Figure 8] This is a side view of the straight-line guide section in Embodiment 2. [Figure 9] This is an enlarged view of the contact area between the guide member and the straight-line guide in Embodiment 2. [Figure 10] This is a front view of a four-group lens barrel showing the arrangement range of the straight-line guide unit in Embodiment 2. [Modes for carrying out the invention]

[0010] The embodiments will be described in detail below with reference to the attached drawings. Note that the following embodiments do not limit the invention as defined in the claims. While the embodiments describe multiple features, not all of these features are essential to the invention, and the features may be combined in any way. Furthermore, in the attached drawings, identical or similar configurations are given the same reference numerals, and redundant descriptions are omitted.

[0011] <Embodiment 1> Figure 1 is a cross-sectional view of the imaging device 1 in Embodiment 1. As shown in Figure 1, the imaging device 1 is configured to have a lens barrel 10 and a camera body 20. The dashed line in the figure represents the optical axis X.

[0012] The camera body 20 has an image sensor 30 and is configured to capture an image formed through the lens barrel 10. The lens barrel 10 is equipped with a mount (mounting part) 101 and is configured to be attachable to (connected to and fixed to) the mount of the camera body 20 (not shown). In this embodiment, the lens barrel 10 and the mount 101 function as interchangeable lenses. By attaching the mount 101 of the lens barrel 10 to the mount of the camera body 20, a communication connection can be established with the camera body 20.

[0013] The guide cylinder 102 is integrally fixed to the mount 101 together with the fixed cylinder 103. A cam ring 104 is held rotatable around the optical axis on the outer periphery of the guide cylinder 102. The cam ring 104 is connected to a zoom ring 105 held rotatable on the outer periphery of the guide cylinder 102 by a key member (not shown), and is configured to rotate integrally by operating the zoom ring 105 from the outside. A zoom sensor (not shown) is attached to the fixed cylinder 103 and is a sensor capable of electrically detecting the rotation angle of the zoom ring 105. The zoom sensor is electrically connected to a control board (control unit) 106 disposed near the mount 101, and transmits focus distance information during zooming to the control circuit.

[0014] The control board 106 is at least one computer including a CPU and a memory, and controls the lens barrel 10 and the imaging device 1 by executing a control program stored in the memory (not shown). The control board 106 controls the imaging device 1 by communicating with a control board (not shown) on the camera body 20 side. That is, the control board 106 can control the imaging device 1 by receiving a predetermined control signal from the control board on the camera body 20 side and executing a control program stored in the memory (not shown). A contact block 107 is electrically connected to the control board 106 and functions to receive communication and power supply from the camera body 20.

[0015] The first group of lenses L1 is fixed to the first group lens barrel 111. The first group lens barrel 111 is fixed to the straight cylinder 112.

[0016] The second group of lenses L2 is held in the second group lens barrel 113, and the second group lens barrel 113 is held movable in a plane orthogonal to the optical axis by a shift unit 114. The shift unit 114 includes an actuator for driving the second group lens barrel 113, a sensor for detecting the driving amount, etc., and is fixed to the guide cylinder 102. The shift unit 114 is electrically connected to the control board 106. The control board 106 drives and controls the second group lens barrel 113 to correct blur based on the blur signal detected by an angular velocity sensor (not shown) attached to the fixed cylinder 103.

[0017] The third group lens L3 is held by the third group lens barrel 115 and fixed to the third group base lens barrel 120. An electromagnetic diaphragm unit 121 is held by the third group base lens barrel 120 and is electrically connected to the control board 106.

[0018] The fourth group lens (moving lens group) L4 is held by the fourth group lens barrel (moving holding frame) 122, and the fourth group lens barrel 122 is held by a guide member 123 described later so as to be movable in the optical axis X direction (along the optical axis direction) with respect to the third group base lens barrel 120. The guide member 123 includes a guide member (guide part) 123a and a guide member 123b. Note that the guide member 123 may be integrally formed with a base member not shown instead of being a member, or may be, for example, a cylindrical part provided on the base member. The fourth group lens L4 is a lens for focus adjustment and is driven in the optical axis X direction by a linear ultrasonic motor 127 held by the third group base lens barrel 120.

[0019] The linear ultrasonic motor 127 includes a fixed part 125 and a movable part 126, and is an actuator that vibrates a piezoelectric element ultrasonically to drive the movable part 126 in the optical axis X direction. The piezoelectric element is electrically connected to the control board 106 by a flexible printed board not shown.

[0020] The fifth group lens L5 is held by the fifth group lens barrel 128. The first group lens L1, the third group lens L3, and the fifth group lens L5 are lenses that move during zooming, and cam followers not shown are fixed to the straight barrel 112, the third group base lens barrel 120, and the fifth group lens barrel 128. Each cam follower engages with a straight groove provided in the guide barrel 102 and a cam groove provided in the cam ring 104, and is configured to be able to move straight in the optical axis X direction by rotating the cam ring 104.

[0021] In addition, since the fourth group lens L4 for focus adjustment is held by the third group base lens barrel 120, it is driven in the optical axis X direction by the linear ultrasonic motor 127 while moving together with the third group base lens barrel 120 during zooming.

[0022] Next, the holding structure of the 4-group lens barrel 122 in this embodiment will be described with reference to Figures 2 to 5. Figure 2 is an exploded perspective view of the configuration for driving the 4-group lens barrel 122 in the optical axis X direction in Embodiment 1. Figure 3 is a front view of the configuration for driving the 4-group lens barrel 122 in the optical axis X direction in Embodiment 1, as seen from the subject side. Figure 4 is a front view of the configuration for driving the 4-group lens barrel 122 in the optical axis X direction in Embodiment 1, excluding the linear ultrasonic motor 127, as seen from the subject side. Figure 5 is an enlarged view of the contact area between the guide member 123a and the straight-line guide part 124 in Embodiment 1.

[0023] The rack (connecting member) 131 has its shaft portion 131a passed through the rack spring 132 and is inserted between the rack shaft holes 122a of the 4-group lens barrel 122, and is held rotatably around the axis of the shaft portion 131a. The hook portion 132a of the rack spring 132 is hooked onto the rack 131, and the extension portion 132b on the opposite side is inserted into the spring hook hole 122c provided in the 4-group lens barrel 122. In this way, the rack 131 is constantly biased in the Y1 direction shown in Figure 3, with the shaft portion 131a as the center of rotation. That is, the rack spring 132 functions as a biasing means that biases the space between the 4-group lens barrel 122 and the guide member 123a (between the movable holding frame and the guide portion).

[0024] Furthermore, the V-groove portion 131b at the tip of the rack 131 is always engaged with a projection (not shown) provided on the movable portion 126 of the linear ultrasonic motor 127. This configuration allows the driving force of the linear ultrasonic motor 127 to be transmitted to the 4-group lens barrel 122 without any looseness due to the biasing force, even if there are variations in the precision of the parts. In other words, the rack 131 transmits the driving force of the linear ultrasonic motor 127, which functions as an actuator, to the 4-group lens barrel 122, which is a movable holding frame.

[0025] Guide members 123a and 123b are each fixed at both ends to the 3-group base lens barrel 120. In this embodiment, guide members 123a and 123b are each formed to be cylindrical in shape. Guide member 123a engages with the engaging portions 124a and 124b of the straight-line guide portion 124 provided on the 4-group lens barrel 122, and holds the 4-group lens barrel 122 so that it can move freely in the optical axis X direction. Guide member 123b is prevented from rotating around guide member 123a by the rotation restricting portion 122b of the 4-group lens barrel 122.

[0026] Next, the shape of the engaging portion 124a will be described. Since the shape of the engaging portion 124b is the same as that of the engaging portion 124a when viewed in the optical axis X direction, its description will be omitted. The engaging portions 124a and 124b are provided at predetermined intervals along the optical axis. Here, as an example, the guide member 123a and the straight-line guide portion 124 are engaged at the positions of the engaging portions 124a and 124b (engagement positions). Two or more such engagement positions may be provided.

[0027] As shown in Figures 3, 4, and 5, the engaging portion 124a contacts the guide member 123a at its contact surface 124c (first contact portion) and contact surface 124d (second contact portion). That is, the straight guide portion 124 provided on the 4-group lens barrel 122 contacts the guide member 123a and guides the 4-group lens barrel 122 along the optical axis X direction.

[0028] As described above, the rack 131 is constantly biased in the direction of arrow Y1 in Figure 3 by the rack spring 132, and the linear ultrasonic motor 127 is held in the 3-group base barrel 120. Therefore, as shown in Figure 4, the 4-group barrel 122 receives a first force F1 exerted by the rack spring 132, which is parallel to the normal direction of the contact surface between the rack 131 and the linear ultrasonic motor 127, on the 4-group barrel 122. Furthermore, the 4-group barrel 122 receives a second force F2 from the guide member 123b, which is parallel to the normal direction of the contact surface between the guide member 123b and the rotation restricting part 122b. Due to the resultant force F3, the contact surface 124c and the contact surface 124d are each biased against the guide member 123a.

[0029] In this way, the biasing member, the rack spring 132, biases the four-group lens barrel 122 and the guide member 123, and also biases the four-group lens barrel 122 and the linear ultrasonic motor 127 (between the moving holding frame and the actuator). As a result, even if the direction of gravity changes due to a change in the attitude of the imaging device 1, the four-group lens barrel 122 can be stably biased against the guide member 123a.

[0030] Furthermore, the contact surfaces 124c and 124d each have curvature. The curvature of the contact surfaces 124c and 124d is set to be smaller than the curvature of the cylindrical guide member 123a. At a minimum, the curvature of the contact surfaces 124c and 124d must be smaller than the curvature of the respective contact surfaces of the guide member 123a that contact the contact surfaces 124c and 124d. This reduces the contact pressure with the guide member 123a compared to the case where the contact area is flat, suppressing wear on the telescope tube, grease depletion, etc., due to long-term use, and improving durability.

[0031] Here, when viewed from the optical axis X direction, the central angle θ of the contact point 124e between the guide member 123a and the contact surface 124c, and the contact point 124f between the guide member 123a and the contact surface 124d, with respect to the arc center A of the guide member 123a, is between 30 degrees and 135 degrees. When the central angle θ is small, a large biasing force is required to keep the contact points 124e and 124f constant regardless of the orientation difference. If the spring force of the rack spring 132 is increased to increase the biasing force on the contact surfaces 124c and 124d of the guide member 123a, the biasing force of the rotation restricting part 122b on the guide member 123b will also increase. As a result, the load during driving increases, and durability deteriorates. On the other hand, when the central angle θ is large, the guide member 123a is tightened too much, which becomes a load during driving.

[0032] Therefore, in this embodiment, the curvature of the contact surface 124c (first contact portion) and the contact surface 124d (second contact portion) is set so that the central angle θ is 30 degrees or more and 135 degrees or less. In addition, in this embodiment, as described above, the guide member 123a and the straight-line guide portion 124 are in contact at two points: the contact point 124e, which is the contact point between the guide member 123a and the contact surface 124c, and the contact point 124f, which is the contact point between the guide member 123a and the contact surface 124d.

[0033] The materials of the four-group telescope tube 122 and the guide member 123a may be resin, one or both, or metal. In other words, regardless of the material, any of the materials will produce the same effects as in this embodiment.

[0034] In this embodiment, the guide member 123a is formed in a cylindrical shape with curvature. However, it is sufficient that at least the contact surface of the guide member 123a that contacts the contact surface 124c, and the contact surface of the guide member 123a that contacts the contact surface 124d, each have curvature. In other words, the guide member 123a is not limited to a cylindrical shape as long as the contact surface of the guide member 123a that contacts the contact surface 124c, and the contact surface of the guide member 123a that contacts the contact surface 124d, each have curvature. For example, a rod-shaped guide member may have other shapes as long as the contact surfaces with the contact surfaces 124c and 124d have curvature, i.e., are arc-shaped. Furthermore, even in the case where only the respective contact surfaces of the guide member 123a that contact the contact surface 124c and the contact surface 124d have curvature, as described above, the curvature of the contact surface 124c and the contact surface 124d is smaller than the curvature of the corresponding contact surface on the guide member 123a.

[0035] Furthermore, although an ultrasonic motor is used to drive the four-group lens barrel 122 in this embodiment, other driving means such as a stepper motor or a voice coil motor may also be used.

[0036] Figure 6 is a perspective view showing a modified example of the biasing means for the four-group lens barrel 122 to the guide member 123a in Embodiment 1. The four-group lens barrel 122 is driven by a voice coil motor 144 and is magnetically biased to the guide member 123a by a biasing member 146. The biasing member 146 is positioned so that each of its contact surfaces 124c and 124d can be biased toward the guide member 123a. By positioning the biasing member 146 in this manner on the four-group lens barrel 122, the biasing member 146 can magnetically bias each of its contact surfaces 124c and 124d toward the guide member 123a.

[0037] In Embodiment 1, the rack spring 132 provides biasing between the guide member 123a and the linear guide section 124, between the guide member 123b and the rotation restricting section 122b, and between the rack 131 and the linear ultrasonic motor 127. However, as in the modified example, the same effect can be achieved even if the biasing members of the guide member 123a and the 4-group lens barrel 122 are independent.

[0038] As described above, by adopting the configuration of Embodiment 1, it is possible to provide a lens barrel that provides stable biasing in various positions while improving durability.

[0039] <Embodiment 2> The following describes an imaging device 1 having a lens barrel 10 according to Embodiment 2. The configuration other than the 4-group lens barrel 222 and the driving method of each lens group are the same as in Embodiment 1, so the explanation will be omitted.

[0040] Figure 7 is a perspective view of the 4-group lens barrel 222 in Embodiment 2. Figure 8 is a side view of the straight-line guide section 224 in Embodiment 2. As shown in Figures 7 and 8, the straight-line guide section 224 has an opening 224a formed in a direction along the optical axis X. The opening 224a has engaging portions 224b (first hole) and engaging portion 224c (second hole) at both ends through which the guide member 123a is inserted. That is, the opening 224a is arranged between the engaging portions 224b and 224c, spaced apart in the direction along the optical axis X. Furthermore, contact portions 224d and 224e, which abut against the guide member 123a, are provided (formed) within the arrangement range in the optical axis X direction where the opening 224a is arranged. Also, similar to Embodiment 1, the 4-group lens barrel 222 is provided with a rotation restricting section 222b.

[0041] In Embodiment 2, the contact portions (224d, 224e) and the engaging portions (224b, 224c) are provided independently. As a result, grooves 224i are formed between each of the contact portions and engaging portions of the straight-line guide portion 224 of Embodiment 2. That is, in the direction along the optical axis X, one groove 224 is formed between the engaging portion 224b and the contact portion 224d, and another groove 224 is formed between the engaging portion 224c and the contact portion 224e.

[0042] The formation of the groove 224i allows for the release of burrs generated during mold splitting, preventing increased sliding load and damage to the guide member 123a. Furthermore, the groove 224i is also utilized as a lubricant reservoir. In other words, the groove 224i holds lubricating oil. The lubricant held in the groove 224i adheres to the guide member 123a located in the groove 224i. As the 4-group lens barrel 122 moves, the contact portions 224d and 224e remove excess lubricant, which is then returned to the groove 224i. As a result, an appropriate amount of lubricant for the smooth movement of the 4-group lens barrel 122 is maintained at the contact points between the guide member 123a and the straight-line guide portion 124. Thus, the groove 224i functions as a part capable of holding the lubricating oil used for the guide member 123. As a result, durability can be improved compared to the case where the contact portion and the engaging portion are located at the same optical axis X-direction position.

[0043] Furthermore, since the contact portions 224d and 224e are formed in the optical axis X direction where the opening 224a is located, the shapes of the contact portions 224d and 224e, as well as the opening 224a, can be formed with a single slide during molding. The contact surfaces 224f and 224g of the guide member 123a and the contact portion 224d are formed parallel to the optical axis X. Therefore, when the contact portion and the engaging portion are located at the same optical axis X position, the contact portion is formed by forcibly removing the mold in the optical axis X direction. On the other hand, when the contact portion is formed simultaneously with the slide that forms the opening 224a, the mold removal direction does not coincide with the optical axis X direction, thus eliminating the need for forced removal and improving the durability of the mold.

[0044] Next, the contact portion 224d of Embodiment 2 will be described. Since the shape of the contact portion 224e is the same as that of the contact portion 224d when viewed in the optical axis X direction, its description will be omitted. Figure 9 is an enlarged view of the contact area between the guide member 123a and the straight-line guide portion 124 in Embodiment 2.

[0045] As shown in Figure 9, the guide member 123a contacts the contact portion 224d, the contact surface 224f, and the contact surface 224g. The shape and effect of the contact surfaces 224f and 224g are the same as in Example 1, so their explanation is omitted.

[0046] Region C shown in Figure 9 is the region that lies away from the optical axis X within a range of ±15 degrees from the arc center A of the guide member 123a and the line N passing through the arc center A and the optical axis X, with the arc center A as the origin. At this time, the contact surfaces 224f and 224g are formed such that the intersection point B of the tangent line L at the contact point 224j of the contact surface 224f between the guide member 123a and the contact surface 224h of the contact surface 224g between the guide member 123a and the contact surface 224g lies outside the region C. That is, when viewed from a direction along the optical axis X, the intersection point of the tangent lines at the two contact points of the contact surface 224f and the contact surface 224g that contact the guide member 123a lies outside the region that lies away from the optical axis within a range of ±15 degrees from the line connecting the optical axis and the origin, with the arc center as the origin. This prevents interference between the slide that forms the opening 224a and the four-group lens barrel 222, allowing for proper molding.

[0047] Next, the arrangement range of the straight-line guide unit 224 will be explained with reference to Figure 10. Figure 10 is a front view of the 4-group lens barrel 222 in orientation D of the lens barrel 10 equipped on the camera body 20 in the camera body 20 in the orientation where the operating unit located on the upper part of the camera body 20 is facing vertically upward in the second embodiment. Arrow G indicates the direction of gravity. In orientation D, the straight-line guide unit 224 is arranged such that, when viewed from the direction along the optical axis X, the center of the arc of the guide member 123a is located outside ±15 degrees from the vertically upward direction (directly upward direction) with respect to the optical axis X, i.e., outside the region E.

[0048] When the direction of gravity in orientation D coincides with the direction of biasing the straight-line guide section 224 onto the guide member 123a, stable biasing can be achieved with a smaller biasing force in orientation D and in orientations of ±90 degrees from orientation D around the optical axis. In this case, since the center A of the arc of the guide member 123a is located outside the region E, the withdrawal direction of the slide forming the opening 224a does not interfere with the 4-group lens barrel 222, making molding possible.

[0049] As described above, the configuration of Embodiment 2 also provides a lens barrel that offers stable biasing in various positions, similar to Embodiment 1, while improving durability.

[0050] The above embodiments have described interchangeable lenses for capturing still images and videos, but similar effects may be obtained, for example, in a lens barrel for recording images. Furthermore, the above embodiments can be applied not only to the focusing lens within the lens barrel, but also to other zoom-moving lenses.

[0051] Although preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of its essence. Furthermore, the above embodiments may be implemented in combination.

[0052] This embodiment includes the following configuration.

[0053] (Composition 1) A group of movable lenses, A movable holding frame for holding the aforementioned movable lens group, A guide portion that holds the aforementioned movable holding frame so that it can move in a direction along the optical axis, It has a biasing member that provides biasing between the movable holding frame and the guide portion, The movable holding frame includes a straight guide portion that contacts the guide portion and is guided along the optical axis direction, The straight-line guide section has a first contact portion and a second contact portion that contact the guide portion when viewed from the direction of the optical axis, The contact surface of the guide portion that contacts the first contact portion, and the contact surface of the guide portion that contacts the second contact portion, each have curvature. The curvature of the first contact portion and the second contact portion is smaller than the curvature of the respective contact surfaces of the guide portion. A lens barrel characterized by the following features.

[0054] (Configuration 2) An actuator that moves the aforementioned movable holding frame in a direction along the optical axis, The system further includes a connecting member that transmits the driving force of the actuator to the movable holding frame, The lens barrel according to configuration 1, characterized in that the biasing member provides biasing between the movable holding frame and the guide portion and between the movable holding frame and the actuator.

[0055] (Composition 3) The lens barrel according to configuration 1 or 2, characterized in that the biasing member biases the first contact portion and the second contact portion toward the guide portion.

[0056] (Composition 4) A lens barrel according to any one of configurations 1 to 3, characterized in that, when viewed from a direction along the optical axis, the central angle between the contact point of the guide portion and the first contact portion and the contact point of the guide portion and the second contact portion, with respect to the center of the arc of the guide portion, is 30 degrees or more and 135 degrees or less.

[0057] (Composition 5) The lens barrel according to any one of configurations 1 to 4, characterized in that the biasing member magnetically biases each of the first contact portion and the second contact portion toward the guide portion.

[0058] (Composition 6) The straight-line guide portion has a first hole through which the guide portion is inserted, and a second hole that is spaced apart from the first hole in a direction along the optical axis. The straight-line guide section has an opening between the first hole and the second hole in a direction along the optical axis, The lens barrel according to any one of configurations 1 to 5, characterized in that the first contact portion and the second contact portion are provided within a range of arrangement in a direction along the optical axis of the opening.

[0059] (Composition 7) The lens barrel according to configuration 6, characterized in that grooves are formed between the first hole and the first contact portion, and between the second hole and the second contact portion, in a direction along the optical axis.

[0060] (Composition 8) The lens barrel according to configuration 7, characterized in that the groove portion holds the lubricating oil used in the guide portion.

[0061] (Composition 9) A lens barrel according to any one of configurations 1 to 8, characterized in that, when viewed from a direction along the optical axis, the intersection points of the tangent lines at the contact point between the guide portion and the first contact portion and the contact point between the guide portion and the second contact portion are located in a region within ±15 degrees from the line connecting the optical axis and the origin, with the center of the arc of the guide portion as the origin, and excluding the region that is separated from the optical axis.

[0062] (Composition 10) The lens barrel according to any one of configurations 1 to 9, characterized in that the center of the guide section is positioned such that, when viewed from a direction along the optical axis, it is located within a range other than ±15 degrees from the vertically upward direction, with respect to the optical axis, in the orientation of the lens barrel which is configured to be attachable to a camera body in which the operating section located at the top of the imaging device is facing vertically upward.

[0063] (Composition 11) The lens barrel according to any one of configurations 1 to 10, characterized in that the guide portion and the straight-line guide portion are in contact at two points: the contact point between the guide portion and the first contact portion and the contact point between the guide portion and the second contact portion.

[0064] (Composition 12) The lens barrel according to configuration 11, characterized in that the guide portion and the straight-line guide portion engage at at least two positions provided at predetermined intervals in the direction along the optical axis, and the guide portion and the straight-line guide portion are in contact at two points at each engagement position.

[0065] (Composition 13) Image sensor and A lens barrel as described in any one of configurations 1 to 11, An imaging device characterized by having the following features. [Explanation of symbols]

[0066] 001 Lens barrel 122 4th group lens barrel 123a Guide member 123b Guide member 124c Contact surface 124d Contact surface

Claims

1. A group of movable lenses, A retaining frame for holding the aforementioned movable lens group, A guide portion that holds the aforementioned holding frame so that it can move in a direction along the optical axis, It has a biasing member that provides biasing between the retaining frame and the guide portion, The retaining frame is equipped with a straight guide portion that contacts the guide portion and is guided in a direction along the optical axis, The straight-line guide section has a first contact portion and a second contact portion that come into contact with the guide portion when viewed along the optical axis. The contact surface of the guide portion that contacts the first contact portion, and the contact surface of the guide portion that contacts the second contact portion, each have curvature. The curvature of the first contact portion and the second contact portion is smaller than the curvature of the respective contact surfaces of the guide portion. A lens barrel characterized by the following features.

2. An actuator for moving the aforementioned holding frame in a direction along the optical axis, The system further includes a connecting member that transmits the driving force of the actuator to the retaining frame, The lens barrel according to claim 1, characterized in that the biasing member biases between the retaining frame and the guide portion and between the retaining frame and the actuator.

3. The lens barrel according to claim 1, characterized in that the biasing member biases the first contact portion and the second contact portion toward the guide portion.

4. The lens barrel according to claim 1, characterized in that, when viewed from a direction along the optical axis, the central angle between the contact point of the guide portion and the first contact portion and the contact point of the guide portion and the second contact portion, with respect to the center of the arc of the guide portion, is 30 degrees or more and 135 degrees or less.

5. The lens barrel according to claim 1, characterized in that the biasing member magnetically biases each of the first contact portion and the second contact portion toward the guide portion.

6. The straight-line guide portion has a first hole through which the guide portion is inserted, and a second hole that is spaced apart from the first hole in a direction along the optical axis. The straight-line guide section has an opening between the first hole and the second hole in a direction along the optical axis. The lens barrel according to claim 1, characterized in that the first contact portion and the second contact portion are provided within an arrangement range in the direction along the optical axis of the opening.

7. The lens barrel according to claim 6, characterized in that grooves are formed between the first hole and the first contact portion, and between the second hole and the second contact portion, in a direction along the optical axis.

8. The lens barrel according to claim 7, characterized in that the groove portion holds the lubricating oil used in the guide portion.

9. The lens barrel according to claim 1, characterized in that, when viewed from a direction along the optical axis, the intersection points of the tangent lines at the contact point between the guide portion and the first contact portion and the contact point between the guide portion and the second contact portion are located in a region of ±15 degrees from the line connecting the optical axis and the origin, with the center of the arc of the guide portion as the origin, and excluding the region that is separated from the optical axis.

10. The lens barrel according to claim 1, characterized in that the center of the guide portion is positioned in a range other than ±15 degrees from the vertically upward direction, when viewed from a direction along the optical axis, with respect to the optical axis, in the orientation of the lens barrel which is configured to be attachable to a camera body in an orientation in which the operating section located at the top of the imaging device is facing vertically upward.

11. The lens barrel according to claim 1, characterized in that the guide portion and the straight-line guide portion are in contact at two points: the contact point between the guide portion and the first contact portion and the contact point between the guide portion and the second contact portion.

12. The lens barrel according to claim 11, characterized in that the guide portion and the straight-line guide portion engage at at least two positions provided at predetermined intervals in the direction along the optical axis, and the guide portion and the straight-line guide portion are in contact at two points at their respective engagement positions.

13. Image sensor and A lens barrel according to any one of claims 1 to 12, An imaging device characterized by having the following features.

Images