Lens barrel and imaging device

Abstract

In order to provide a lens barrel having good optical performance, this lens barrel is provided with: a first lens holding frame that holds a first lens; a first guide shaft that guides the first lens holding frame in an optical axis direction; a contact member that is in contact with the first guide shaft; and a biasing member that is in contact with the first lens holding frame and biases the contact member toward the first guide shaft.

Description

[Technical field]

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

[0002] Lens barrels are required to have good optical performance (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-168492 A Summary of the Invention

[0004] According to a first aspect, a lens barrel includes a first lens holding frame that holds a first lens, a first guide shaft that guides the first lens holding frame in an optical axis direction, and a contact member that contacts the first guide shaft. a support member that supports the contact member and is movable relative to the first lens holding frame; and a support member that is provided between the first lens holding frame and the support member, biasing the first guide shaft This causes the contact member to come into contact with the first guide shaft. A biasing member. R .

[0005] According to a second aspect, an imaging device includes the above-described lens barrel.

[0006] The configurations of the embodiments described below may be appropriately improved, and at least a part of them may be replaced with other components. Furthermore, components that are not particularly limited in terms of their location may be located in any location that can achieve their function, not limited to the location disclosed in the embodiments. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing a camera including a lens barrel and a camera body according to an embodiment. [Diagram 2] FIG. 2 is a perspective view of the movable cylinder as seen from the camera body side. [Diagram 3]3(A) and 3(B) are schematic perspective views of the seventh lens retaining frame, and FIG. 3(C) is a sectional view for explaining the engagement between the seventh lens retaining frame and the guide bar. [Figure 4] FIG. 4(A) is a schematic perspective view of the eighth lens retaining frame, and FIG. 4(B) is a cross-sectional view for explaining the engagement between the eighth lens retaining frame and the guide bar. [Diagram 5] FIG. 5(A) is a diagram of the movable cylinder with the fixed part removed, as viewed from the camera body side, and FIG. 5(B) is an enlarged, partially cross-sectional view of the first engagement part and its vicinity in FIG. 5(A). [Figure 6] 6(A) and 6(B) are perspective views showing the seventh lens retaining frame, the eighth lens retaining frame, the first driving source unit, and the second driving source unit. [Figure 7] Figure 7(A) is a plan view of the ninth lens group and the ninth lens retaining frame as viewed from the subject side, Figure 7(B) is an oblique view of the ninth lens group and the ninth lens retaining frame as viewed from the subject side, and Figure 7(C) is an oblique view of the ninth lens group and the ninth lens retaining frame as viewed from the camera body side. [Figure 8] FIG. 8(A) is a diagram for explaining the relationship between the seventh lens retaining frame and the ninth lens group when the seventh lens group is closest to the ninth lens group, and FIG. 8(B) is a cross-sectional view taken along line BB in FIG. 8(A). [Figure 9] FIG. 9 is a diagram for explaining the length of the guide bar and the engagement length between the guide bar and the first engagement portion in one embodiment. [Figure 10] 10(A) and 10(B) are diagrams for explaining the size of the movable cylinder, the length of the guide bar, and the engagement length between the guide bar and the first engagement portion when the ninth lens group is circular. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] A lens barrel 100 according to an embodiment will be described in detail below with reference to the drawings. Note that in each drawing, some elements may be omitted in order to facilitate understanding.

[0009] 1 is a diagram showing a camera 1 equipped with a lens barrel 100 according to this embodiment and a camera body 101. In this embodiment, the lens barrel 100 is detachable from the camera body 101 by a lens mount LM. Although they are detachable, the lens barrel 100 and the camera body 101 may be integrated together.

[0010] The camera body 101 includes an image sensor (not shown) that captures a subject image formed by a group of lenses arranged inside the lens barrel 100 and converts the image into an electrical signal.

[0011] As shown in Fig. 1, the lens barrel 100 according to this embodiment includes a first lens group L1 to a ninth lens group L9 arranged in sequence along a common optical axis OA. The first lens group L1 to the ninth lens group L9 are held in a first lens holding frame F1 to a ninth lens holding frame F9, respectively. In the lens barrel 100 according to this embodiment, the seventh lens group L7 and the eighth lens group L8 are each a focus lens group. Each lens group may be composed of one lens or multiple lenses.

[0012] Furthermore, the lens barrel 100 has a first guide bar 27, a second guide bar 28 (not shown in FIG. 1), and a rotation restriction bar 29. The first guide bar 27 guides the seventh lens holding frame F7 in the optical axis OA direction, and the second guide bar 28 guides the eighth lens holding frame F8 in the optical axis OA direction. The rotation restriction bar 29 restricts the rotation of the seventh lens holding frame F7 about the first guide bar 27 as an axis and the rotation of the eighth lens holding frame F8 about the second guide bar 28 as an axis. The first guide bar 27, the second guide bar 28, and the rotation restriction bar 29 are fixed to a movable barrel 110 that moves in the optical axis OA direction by the user's operation of the zoom operation ring.

[0013] Fig. 2 is a perspective view of the movable barrel 110 as viewed from the camera body 101 side. As shown in Fig. 2, the movable barrel 110 includes a barrel portion 112 and a fixed portion 113. The movable barrel 110 also includes a cam pin 111 that protrudes from the outer circumferential surface of the barrel portion 112 in a direction intersecting with the optical axis OA direction.

[0014] 1, lens barrel 100 includes fixed barrel 120, which is disposed radially outward of movable barrel 110, and cam barrel 130, which is disposed radially outward of fixed barrel 120 and is rotatable about optical axis OA. Cam barrel 130 rotates about optical axis OA in conjunction with rotation of the zoom operation ring.

[0015] A linear groove (not shown in FIG. 1) extending in the optical axis OA direction is formed in the fixed barrel 120, and a cam groove 131 is formed in the cam barrel 130. The cam pin 111 of the movable barrel 110 passes through the linear groove of the fixed barrel 120 and is slidably fitted into the cam groove 131 of the cam barrel 130. As a result, when the cam barrel 130 rotates about the optical axis OA in conjunction with the rotation of the zoom operation ring, the movable barrel 110 is moved linearly in the optical axis OA direction along the cam groove 131 and the linear groove. The cam pin 111 may be, for example, a cam follower or the like.

[0016] Thus, in the lens barrel 100 according to the present embodiment, the position of the movable barrel 110 in the optical axis OA direction relative to the ninth lens group L9 changes. Because the first guide bar 27, the second guide bar 28, and the rotation restriction bar 29 are fixed to the movable barrel 110, when the movable barrel 110 moves in the optical axis OA direction, the positions of the first guide bar 27, the second guide bar 28, and the rotation restriction bar 29 relative to the ninth lens group L9 also change.

[0017] Next, the configurations of the seventh lens retaining frame F7 and the eighth lens retaining frame F8 will be described. Figures 3(A) and 3(B) are schematic perspective views of the seventh lens retaining frame F7, and Figure 3(C) is a cross-sectional view for explaining the engagement between the seventh lens retaining frame F7 and the first guide bar 27. Figure 4(A) is a schematic perspective view of the eighth lens retaining frame F8, and Figure 4(B) is a cross-sectional view for explaining the engagement between the eighth lens retaining frame F8 and the second guide bar 28.

[0018] First, the seventh lens holding frame F7 will be described. As shown in Fig. 3(A) and Fig. 3(B), the seventh lens holding frame F7 has a cylinder portion 30 that holds the seventh lens group L7, and a first engagement portion 31 that engages with the first guide bar 27 and a first protrusion 32 that engages with the rotation restriction bar 29 are provided on the outer periphery of the cylinder portion 30.

[0019] 3(B) and 3(C), the first engagement portion 31 has two first plate-shaped portions 311a and 311b spaced apart in the direction of the optical axis OA and substantially perpendicular to the central axis AX1 of the first guide bar 27. The first plate-shaped portions 311a and 311b are respectively formed with holes 315a and 315b through which the first guide bar 27 is inserted.

[0020] 3(C), a biasing mechanism 50 is provided inside the first engagement portion 31. The biasing mechanism 50 includes a bearing 51, a bearing support portion 52, and a compression spring 53.

[0021] The bearing 51 is, for example, a ball bearing having a cylindrical outer shape. The bearing 51 is supported by a bearing support portion 52 and contacts the first guide bar 27. The bearing support portion 52 does not contact the first guide bar 27. That is, a part of the bearing 51 is located outside the bearing support portion 52 in the radial direction of a circle centered on the optical axis OA. Alternatively, a part of the bearing 51 protrudes toward the first guide bar 27 beyond the bearing support portion 52. Note that the bearing 51 is not limited to a ball bearing, and may be a general sliding bearing. The bearing 51 may be, for example, a roller bearing or a free ball bearing.

[0022] One end of the compression spring 53 contacts the first engagement portion 31, and the other end contacts the bearing support portion 52. That is, the compression spring 53 is provided between the first engagement portion 31 (the seventh lens holding frame F7) and the bearing support portion 52. The compression spring 53 biases the bearing 51 toward the first guide bar 27 via the bearing support portion 52. More specifically, the compression spring 53 biases the bearing support portion 52 toward the first guide bar 27 (in the direction indicated by the arrow A1 in FIG. 3(C)). As a result, the bearing 51 is also biased toward the first guide bar 27 (see the arrow A6) and pressed against the first guide bar 27. As a result, the first engagement portion 31 is pressed against the first guide bar 27 (see the arrow A7). More specifically, the inner circumferential surfaces of the holes 315a and 315b are pressed against the first guide bar 27. This suppresses rattling between first guide bar 27 and holes 315a, 315b (seventh lens retaining frame F7) of first engagement portion 31. Note that instead of compression spring 53, for example, a torsion spring or an elastic body such as rubber may be used. Also, a leaf spring may be used. Also, bearing 51 may be biased toward first guide bar 27 without using bearing support portion 52.

[0023] The direction of the biasing force of the compression spring 53 will be described in more detail below. Fig. 5(A) is a diagram of the movable barrel 110 with the fixed part 113 removed, as viewed from the camera body 101 side, and Fig. 5(B) is an enlarged, partially cross-sectional view of the vicinity of the first engagement part 31 in Fig. 5(A).

[0024] As shown in Fig. 5(A), first guide bar 27 and second guide bar 28 are disposed symmetrically with respect to a straight line SL1 connecting center axis AX3 of rotation restriction bar 29 and the optical axis OA in a plane perpendicular to the optical axis OA. Note that the cross-sectional view of Fig. 1 is a cross-sectional view taken along line AA in Fig. 5(A).

[0025] 5(B), bearing 51 is disposed on a straight line SL2 connecting the optical axis OA and the central axis AX1 of first guide bar 27 in a plane perpendicular to the optical axis OA. More specifically, bearing 51 is disposed such that its central axis AX4 is substantially perpendicular to the straight line SL2 in the plane perpendicular to the optical axis OA. In other words, bearing 51 is disposed such that a straight line passing through contact point CP1 between bearing 51 and first guide bar 27 and representing the diameter of bearing 51 is substantially parallel to straight line SL2 in the plane perpendicular to the optical axis OA.

[0026] As shown by arrow A2 in Fig. 5B, the bearing 51 is biased by the compression spring 53 toward the first guide bar 27 (outside) in a direction substantially parallel to the straight line SL2. As a result, the first engagement portion 31 is pressed against the first guide bar 27 in a direction substantially parallel to the straight line SL2, as shown by arrow A3 in Fig. 5B. This suppresses play between the first guide bar 27 and the holes 315a, 315b of the first engagement portion 31. In addition, because the direction in which the first engagement portion 31 is pressed against the first guide bar 27 is substantially parallel to the straight line SL2, it is possible to suppress deviation of the central axis of the seventh lens group L7 from the optical axis OA.

[0027] Next, the eighth lens holding frame F8 will be described. As shown in Fig. 4(A), the eighth lens holding frame F8 has a cylinder portion 40 that holds the eighth lens group L8, and a second engagement portion 41 that engages with the second guide bar 28 and a second protrusion 42 that engages with the rotation restriction bar 29 are provided on the outer periphery of the cylinder portion 40.

[0028] A sheet S1 is disposed on the rear side (camera body 101 side) of eighth lens group L8 in the direction of the optical axis OA. Sheet S1 has an opening shaped like a circle with the top and bottom cut out in a plane perpendicular to the optical axis OA, and prevents light that enters lens barrel 100 from the subject side and is reflected by first guide bar 27, second guide bar 28, and rotation restriction bar 29 from entering the imaging range of the image sensor.

[0029] 4(A) and 4(B), the second engagement portion 41 has two second plate-shaped portions 411a and 411b spaced apart in the direction of the optical axis OA and substantially perpendicular to the central axis AX2 of the second guide bar 28. The second plate-shaped portions 411a and 411b are respectively formed with holes 415a and 415b through which the second guide bar 28 is inserted.

[0030] 4(B), a biasing mechanism 50 is provided inside the second engagement portion 41. The configuration of the biasing mechanism 50 is similar to that of the biasing mechanism 50 provided inside the first engagement portion 31, and therefore a detailed description thereof will be omitted.

[0031] As shown in FIG. 4B, compression spring 53 biases bearing support portion 52 toward second guide bar 28 (in the direction indicated by arrow A1 in FIG. 4B). As a result, bearing 51 is also biased toward second guide bar 28 (see arrow A6) and pressed against second guide bar 28. As a result, second engagement portion 41 is pressed against second guide bar 28 (see arrow A7). More specifically, the inner circumferential surfaces of holes 415a and 415b are pressed against second guide bar 28. As a result, rattling between second guide bar 28 and holes 415a and 415b (eighth lens holding frame F8) of second engagement portion 41 is suppressed.

[0032] In FIG. 5B, the cross section is omitted, but the bearing 51 in the second engagement portion 41 is disposed on a straight line SL3 that connects the optical axis OA and the central axis AX2 of the second guide bar 28 in a plane perpendicular to the optical axis OA. As shown by an arrow A4 in FIG. 5B, the bearing 51 in the second engagement portion 41 is biased toward the second guide bar 28 (outside) in a direction substantially parallel to the straight line SL3 by a compression spring 53. As a result, the second engagement portion 41 is pressed against the second guide bar 28 in a direction substantially parallel to the straight line SL3, as shown by an arrow A5 in FIG. 5B. This suppresses backlash between the second guide bar 28 and the holes 415a, 415b of the second engagement portion 41. In addition, since the direction in which the second engagement portion 41 is pressed against the second guide bar 28 is substantially parallel to the straight line SL3, it is possible to suppress the central axis of the eighth lens group L8 from deviating from the optical axis OA.

[0033] Next, the driving of the seventh lens retaining frame F7 and the eighth lens retaining frame F8 will be described. The seventh lens retaining frame F7 is driven by the first driving source unit 70, and the eighth lens retaining frame F8 is driven by the second driving source unit 80. Figures 6(A) and 6(B) are perspective views showing the seventh lens retaining frame F7, the eighth lens retaining frame F8, the first driving source unit 70, and the second driving source unit 80.

[0034] When a user rotates the focus operation ring, an encoder (not shown) detects the rotation of the focus operation ring, and a control unit (not shown) drives a stepping motor 701 of the first driving source unit 70 and a stepping motor 801 of the second driving source unit 80 (described later) in accordance with the amount of rotation of the focus operation ring to move the seventh lens holding frame F7 and the eighth lens holding frame F8, respectively. Also, during autofocus, the control unit (not shown) drives the stepping motor 701 of the first driving source unit 70 and the stepping motor 801 of the second driving source unit 80.

[0035] The first driving source unit 70 has a stepping motor 701, a lead screw 702, a rack 703, and a mounting member 704. Instead of the first driving source unit 70, a voice coil motor, an ultrasonic motor, or the like may be used.

[0036] The lead screw 702 is directly connected to the output shaft of the stepping motor 701 and is driven to rotate by the stepping motor 701 .

[0037] A stepping motor 701 is fixed to the mounting member 704. The mounting member 704 also rotatably supports a lead screw 702. A plurality of holes are formed in the mounting member 704, and the first drive source unit 70 is fixed to the movable barrel 110 by fixing the mounting member 704 to the movable barrel 110 with screws 705 or the like (see FIG. 2).

[0038] The rack 703 has a connecting portion that is connected to the first engagement portion 31, and a contact portion that contacts the lead screw 702. The contact portion has a thread that is complementary to the thread of the lead screw 702. As a result, when the lead screw 702 is rotated by the stepping motor 701, the rack 703 moves. As the rack 703 moves, the first engagement portion 31 that is connected to the connecting portion of the rack 703 moves linearly in the optical axis OA direction, guided by the first guide bar 27. As a result, the seventh lens retaining frame F7 can move linearly in the optical axis OA direction when the lead screw 702 is rotationally driven.

[0039] The second drive source unit 80 has a stepping motor 801, a lead screw 802, a rack 803, and a mounting member 804. Instead of the second drive source unit 80, a voice coil motor, an ultrasonic motor, or the like may be used.

[0040] The lead screw 802 is directly connected to the output shaft of the stepping motor 801 and is rotated by the stepping motor 801 .

[0041] A stepping motor 801 is fixed to the mounting member 804. The mounting member 804 also rotatably supports a lead screw 802. A plurality of holes are formed in the mounting member 804, and the second drive source unit 80 is fixed to the movable barrel 110 by fixing the mounting member 804 to the movable barrel 110 with screws 805 or the like (see FIG. 2).

[0042] Similarly, the rack 803 has a connecting portion that is connected to the second engaging portion 41, and a contact portion that contacts the lead screw 802. The contact portion has a thread that is complementary to the thread of the lead screw 802. As a result, when the lead screw 802 is rotated by the stepping motor 801, the rack 803 moves. As the rack 803 moves, the second engaging portion 41 that is connected to the connecting portion of the rack 803 moves linearly in the optical axis OA direction, guided by the second guide bar 28. As a result, the eighth lens retaining frame F8 can move linearly in the optical axis OA direction when the lead screw 802 is rotationally driven.

[0043] Next, the configuration of the ninth lens group L9 and the ninth lens holding frame F9 will be described. Fig. 7(A) is a plan view of the ninth lens group L9 and the ninth lens holding frame F9 seen from the subject side, Fig. 7(B) is a perspective view of the ninth lens group L9 and the ninth lens holding frame F9 seen from the subject side, and Fig. 7(C) is a perspective view of the ninth lens group L9 and the ninth lens holding frame F9 seen from the camera body 101 side. In Fig. 7(A), the outer periphery of the ninth lens group L9 is indicated by a dotted line.

[0044] 7A, the ninth lens group L9 has a planar shape in a plane perpendicular to the optical axis OA that is a shape of a circle with the top and bottom cut out (an oval shape or a racetrack shape). That is, the outer periphery of the ninth lens group L9 has two opposing arcuate outer peripheries 61 and a straight outer periphery 62 connecting the arcuate outer peripheries.

[0045] Sheets S2 and S3 are disposed in front of and behind ninth lens group L9 in the direction of optical axis OA. Each of sheets S2 and S3 has an opening shaped like a circle with the top and bottom cut out in a plane perpendicular to the optical axis OA, and prevents light that enters lens barrel 100 from the subject side and is reflected by first guide bar 27, second guide bar 28, and rotation restriction bar 29 from entering the imaging range of the imaging element.

[0046] In this embodiment, the ninth lens group L9 has a shape of a circle with the top and bottom cut out, so that there are spaces above and below the ninth lens group L9, into which a part of the seventh lens retaining frame F7 and a part of the eighth lens retaining frame F8 can enter.

[0047] Fig. 8(A) is a diagram for explaining the relationship between the seventh lens holding frame F7 and the ninth lens group L9 when the seventh lens group L7 is closest to the ninth lens group L9, and Fig. 8(B) is a cross-sectional view taken along line BB in Fig. 8(A). Note that Fig. 8(A) shows a state in which the zoom position is at the wide end and the seventh lens group L7 and the eighth lens group L8 are at the closest end.

[0048] 8A, in this embodiment, when the seventh lens group L7 and the ninth lens group L9 are closest to each other, a part of the first engagement portion 31 of the seventh lens holding frame F7 is located closer to the camera body 101 (image side) than the surface (frontmost surface) of the ninth lens group L9 closest to the subject in the optical axis OA direction. More specifically, when the seventh lens group L7 and the ninth lens group L9 are closest to each other, a part of the first engagement portion 31 of the seventh lens holding frame F7 is located closer to the camera body 101 than the surface (frontmost surface) of the ninth lens group L9 closest to the subject in the optical axis OA direction in a region R1 between the outer periphery of the ninth lens holding frame F9 and the outer periphery of the ninth lens group L9.

[0049] In other words, when the seventh lens group L7 and the ninth lens group L9 are closest to each other, the first engagement portion 31 and the ninth lens group L9 overlap in the radial direction of a circle centered on the optical axis OA, as shown in Fig. 8(B). The same is true for the eighth lens group L8 and the eighth lens holding frame F8.

[0050] Next, the advantage of making the planar shape of the ninth lens group L9 a shape with the top and bottom of a circle cut out (oval shape or racetrack shape) will be described. FIG. 9 is a diagram for explaining the length of the first guide bar 27 and the engagement length between the first guide bar 27 and the first engagement portion 31 in this embodiment, and FIG. 10(A) and FIG. 10(B) are diagrams for explaining the size of the movable barrel 110, the length of the first guide bar 27, and the engagement length between the first guide bar 27 and the first engagement portion 31 when the planar shape of the ninth lens group L9 is circular. Note that FIG. 9, FIG. 10(A), and FIG. 10(B) show the state in which the seventh lens group L7 is closest to the ninth lens group L9. Note that in the following description, the first guide bar 27 and the seventh lens group L7 will be described, but the same applies to the second guide bar 28 and the eighth lens group L8.

[0051] In the case where the planar shape of the ninth lens group L9 is circular, if the diameter of the movable barrel 110 is the same as that of the present embodiment, the rear end of the movable barrel 110 hits the ninth lens holding frame F9 in the optical axis OA direction. Here, as shown in FIG. 10(A), if the inner diameter of the fixed portion 113 is made larger than the outer diameter of the ninth lens group L9 and the diameter of the tube portion 112 is made larger, the rear end of the movable barrel 110 can be positioned closer to the camera body 101 than the surface of the ninth lens group L9 closest to the subject. However, in this case, the diameter of the movable barrel 110 becomes larger, so the lens barrel 100 becomes larger. Also, compared to the case of FIG. 9, the first guide bar 27 and the second guide bar 28 are disposed radially outward, and the first guide bar 27 and the second guide bar 28 are separated from the optical axis OA, so that the guidance of the seventh lens group L7 and the eighth lens group L8 becomes unstable. Also, in order to prevent the rear end of the movable barrel 110 from colliding with the ninth lens holding frame F9 without changing the size of the movable barrel 110, for example, the length of the movable barrel 110 in the optical axis OA direction is shortened as shown in Fig. 10(B), which also shortens the length of the first guide bar 27.

[0052] Even if the length of the first guide bar 27 is shortened, the positional relationship between the seventh lens group L7 and the ninth lens group L9 at the infinity end and the close end does not change, so the length of the first engagement portion 31 in the optical axis OA direction is also shortened. That is, the engagement length between the first engagement portion 31 and the first guide bar 27 becomes shorter, and there is a risk that the seventh lens group L7 will tilt with respect to the optical axis direction. More specifically, when the positions of the holes 315a and 315b are shifted by a certain amount on a plane perpendicular to the optical axis OA, the shorter the engagement length between the first engagement portion 31 and the first guide bar 27, the greater the tilt that occurs.

[0053] In this embodiment, as shown in FIG. 9, the movable barrel 110 is inserted into the space created by forming the ninth lens group L9 into a shape with the top and bottom of the circle cut out, and the rear end (the end on the camera body 101 side (image side)) of the movable barrel 110 can be positioned closer to the camera body 101 than the surface of the ninth lens group L9 closest to the subject. This allows the movable barrel 110 to be positioned without increasing its size, as shown in FIG. 9. In addition, the length L12 of the first guide bar 27 can be made longer than when the ninth lens group L9 is circular (L14 in FIG. 10B). In addition, since the first guide bar 27 is longer, the engagement length L11 between the first engagement portion 31 and the first guide bar 27 (the distance between the first plate-shaped portions 311a and 311b of the first engagement portion 31) can be made longer than when the ninth lens group L9 is circular (L13 in FIG. 10B).

[0054] In this embodiment, since the distance L11 between the holes 315a and 315b can be increased, even if the positions of the holes 315a and 315b are shifted by a certain amount on a plane perpendicular to the optical axis OA, the inclination of the seventh lens holding frame F7 with respect to the optical axis OA can be reduced. In addition, the longer the distance L11 between the holes 315a and 315b, the smaller the lateral pressure applied to the holes 315a and 315b may be. Specifically, when the camera 1 is turned upward or downward, the weight of the seventh lens group L7 and the seventh lens holding frame F7 causes the seventh lens holding frame F7 to tilt around the hole 315a or the hole 315b as a fulcrum, generating lateral pressure in the holes 315a and 315b. In this case, if the distance L11 is long, the lateral pressure can be reduced by the principle of leverage, and the friction between the inner surfaces of the holes 315a and 315b and the first guide bar 27 is reduced. This allows the load on the stepping motor 701 to be reduced.

[0055] As described above in detail, the lens barrel 100 according to this embodiment includes the seventh lens holding frame F7 that holds the seventh lens group L7, the first guide bar 27 that guides the seventh lens holding frame F7 in the optical axis OA direction, the bearing 51 that contacts the first guide bar 27, and the compression spring 53 that contacts the seventh lens holding frame F7 and urges the bearing 51 toward the first guide bar 27. The compression spring 53, one end of which contacts the seventh lens holding frame F7, urges the bearing 51 toward the first guide bar 27, so that the seventh lens holding frame F7 is pressed against the first guide bar 27. More specifically, the inner circumferential surfaces of the holes 315a, 315b of the first engagement portion 31 of the seventh lens holding frame F7 are pressed against the first guide bar 27. This makes it possible to suppress backlash between the first guide bar 27 and the holes 315a, 315b (backlash between the first guide bar 27 and the seventh lens holding frame F7).

[0056] Furthermore, in this embodiment, bearing 51 is pressed against first guide bar 27 by compression spring 53. This allows bearing 51 to be kept in contact with first guide bar 27, thereby suppressing rattling between first guide bar 27 and holes 315a, 315b.

[0057] In this embodiment, the lens barrel 100 includes a bearing support portion 52 that supports the bearing 51, and the compression spring 53 is provided between the seventh lens holder frame F7 and the bearing support portion 52, biasing the bearing support portion 52 toward the first guide bar 27, and at least a portion of the bearing 51 is located outside the bearing support portion 52 in the radial direction of a circle centered on the optical axis OA. By using the bearing support portion 52, the bearing 51 can be easily biased toward the first guide bar 27. In addition, since the bearing support portion 52 does not contact the first guide bar 27, the torque required to move the seventh lens holder frame F7 in the optical axis OA direction can be reduced compared to the case where the bearing support portion 52 contacts the first guide bar 27. This reduces the load on the stepping motor 701.

[0058] In this embodiment, the bearing 51 rotates with the movement of the seventh lens retaining frame F7. This allows the seventh lens retaining frame F7 to move smoothly in the optical axis OA direction. In addition, the torque required to move the seventh lens retaining frame F7 in the optical axis OA direction can be reduced, and the load on the stepping motor 701 can be reduced.

[0059] In this embodiment, in a plane perpendicular to the optical axis OA, bearing 51 is disposed on a straight line SL2 connecting the central axis AX1 of first guide bar 27 and the optical axis OA, thereby making it possible to prevent the central axis of seventh lens group L7 from shifting from the optical axis OA.

[0060] In this embodiment, the direction of the biasing force of the compression spring 53 (see arrow A2 in FIG. 5B) is substantially parallel to the straight line SL2. As a result, the seventh lens retaining frame F7 that retains the seventh lens group L7 is pressed against the first guide bar 27 in a direction substantially parallel to the straight line SL2, so that it is possible to prevent the central axis of the seventh lens group L7 from shifting from the optical axis OA.

[0061] In this embodiment, bearing 51 has a cylindrical outer shape, and in a plane perpendicular to the optical axis OA, the central axis AX4 of bearing 51 is substantially perpendicular to the straight line SL2. This allows the direction in which bearing 51 is pressed against first guide bar 27 to be substantially parallel to the straight line SL2, and the seventh lens retaining frame F7 is pressed against first guide bar 27 in a direction substantially parallel to the straight line SL2, thereby preventing the central axis of seventh lens group L7 from deviating from the optical axis OA.

[0062] Furthermore, in this embodiment, the seventh lens retaining frame F7 has holes 315a and 315b spaced apart in the optical axis OA direction and through which the first guide bar 27 is inserted, and a bearing 51 is disposed between the holes 315a and 315b in the optical axis OA direction. This allows the holes 315a and 315b to be pressed against the first guide bar 27 in a well-balanced manner. Also, the space within the first engagement portion 31 can be effectively utilized.

[0063] In this embodiment, the lens barrel 100 includes a ninth lens group L9 arranged closer to the image side than the seventh lens group L7, and the ninth lens group L9 has a shape of a circle with the top and bottom cut out on a plane perpendicular to the optical axis OA. This allows the ninth lens group L9 to be lightweight, and therefore the lens barrel 100 to be lightweight.

[0064] In addition, in this embodiment, when the seventh lens group L7 and the ninth lens group L9 are closest to each other, a part of the seventh lens holding frame F7 (a part of the first engagement portion 31) is located closer to the image side than the surface of the ninth lens group L9 closest to the subject in the optical axis OA direction. In other words, when the seventh lens group L7 and the ninth lens group L9 are closest to each other, the ninth lens group L9 and a part of the seventh lens holding frame overlap in the radial direction of a circle centered on the optical axis OA. This allows the distance between the first guide bar 27 and the optical axis OA to be closer than when the planar shape of the ninth lens group L9 is circular. Since the first guide bar 27 is closer to the optical axis OA, the radial distance centered on the optical axis OA of the connection portion connecting the cylinder portion 30 of the seventh lens holding frame F7 to the first engagement portion 31 can be shortened. This allows the weight of the seventh lens holding frame F7 to be reduced, and thus the weight of the lens barrel 100 to be reduced. Furthermore, since the length of first guide bar 27 and the distance between holes 315a and 315b can be increased, the inclination of the central axis of seventh lens group L7 with respect to the optical axis OA can be suppressed.

[0065] In this embodiment, the lens barrel 100 includes an eighth lens holding frame F8 that holds the eighth lens group L8, and a second guide bar 28 that guides the eighth lens holding frame F8 in the optical axis OA direction. When the eighth lens group L8 and the ninth lens group L9 are closest to each other, a part of the eighth lens holding frame F8 is located closer to the image side than the surface of the ninth lens group L9 that is closest to the subject in the optical axis OA direction. This allows the distance between the second guide bar 28 and the optical axis OA to be closer than when the planar shape of the ninth lens group L9 is circular. Since the second guide bar 28 is closer to the optical axis OA, the radial distance of the connecting portion that connects the tube portion 40 and the second engagement portion 41 of the eighth lens holding frame F8, centered on the optical axis OA, can be shortened. This allows the eighth lens holding frame F8 to be lighter in weight, and therefore the lens barrel 100 to be lighter in weight. Furthermore, since the length of the second guide bar 28 and the distance between the holes 415a and 415b can be increased, the inclination of the central axis of the eighth lens group L8 with respect to the optical axis OA can be suppressed.

[0066] In the above embodiment, bearing 51 may be a resin bearing, or may be one in which a resin such as polyacetal is pressed into the outer diameter. Also, instead of bearing 51, for example, a metal, plastic, or resin member other than bearing 51 may be brought into contact with first guide bar 27 and second guide bar 28. Also, the outer shape of the member that comes into contact with first guide bar 27 and second guide bar 28 is not limited to a cylindrical shape, and may be, for example, a rectangular parallelepiped shape.

[0067] In the above embodiment, the lens barrel 100 includes a plurality of focus lens groups, but the above embodiment can also be applied to a case where there is only one focus lens group. Also, in the above embodiment, the lens barrel 100 is a zoom lens, but it may be a fixed focal length lens.

[0068] Furthermore, the number and arrangement of lens groups included in the lens barrel 100 are not limited to those in the above embodiment. Furthermore, the configuration for moving the movable barrel 110 in the optical axis OA direction is not limited to those in the above embodiment. For example, the movable barrel 110 may be guided in the optical axis OA direction by a guide bar instead of a linear groove. Furthermore, the movable barrel 110 may be a fixed barrel that does not move in the optical axis OA direction. Furthermore, the first drive source unit 70 and the second drive source unit 80 have been described as having racks, but may also be configured to have nuts.

[0069] The above-described embodiment is a preferred example, but is not limited thereto, and various modifications are possible without departing from the scope of the present invention, and any combination of components may be used. [Explanation of symbols]

[0070] 1 Camera 27 First guide bar 28 2nd guide bar 51 Bearing 52 Bearing support 53 Compression Spring 100 Lens barrel 101 Camera Body 110 Mobile Cylinder 315a,315b hole 415a, 415b Hole F7 7th lens holder F8 8th lens holder F9 9th lens holder L7 7th lens group L8 8th lens group L9 9th lens group

Claims

1. a first lens holding frame that holds a first lens; a first guide shaft that guides the first lens holding frame in an optical axis direction; A contact member that comes into contact with the first guide shaft; a support member that supports the contact member and is movable with respect to the first lens holding frame; a biasing member provided between the first lens holding frame and the support member, the biasing member biasing the support member toward the first guide shaft to bring the contact member into contact with the first guide shaft; A lens barrel comprising:

2. The contact member is pressed against the first guide shaft by the biasing member. The lens barrel according to claim 1 .

3. The contact member and the biasing member are disposed on a straight line substantially parallel to an optical axis. The lens barrel according to claim 1 or 2.

4. the contact member rotates in association with the movement of the first lens holding frame. The lens barrel according to any one of claims 1 to 3.

5. In a plane perpendicular to the optical axis, the contact member is disposed on a straight line connecting a central axis of the first guide shaft and the optical axis. The lens barrel according to any one of claims 1 to 4.

6. The direction of the biasing force by the biasing member is substantially parallel to the straight line. The lens barrel according to claim 5 .

7. The contact member has a cylindrical outer shape, In a plane perpendicular to the optical axis, the central axis of the contact member is substantially perpendicular to the straight line.

7. The lens barrel according to claim 5 or 6.

8. the first lens holding frame has a first hole and a second hole spaced apart from each other in the optical axis direction and through which the first guide shaft is inserted, The contact member is disposed between the first hole and the second hole in the optical axis direction. The lens barrel according to any one of claims 1 to 7.

9. a second lens disposed closer to the image side than the first lens; The second lens has a shape obtained by cutting out the top and bottom of a circle on a plane perpendicular to the optical axis. The lens barrel according to any one of claims 1 to 8.

10. When the first lens and the second lens are closest to each other, a part of the first lens holding frame is located closer to an image side than a surface of the second lens closest to an object side in the optical axis direction. The lens barrel according to claim 9.

11. When the first lens and the second lens are closest to each other, the second lens and a part of the first lens holding frame overlap in a radial direction of a circle centered on the optical axis. The lens barrel according to claim 10.

12. a third lens holding frame that holds a third lens; a second guide shaft that guides the third lens holding frame in the optical axis direction, When the third lens and the second lens are closest to each other, a part of the third lens holding frame is located closer to an image side than a surface of the second lens closest to an object side in the optical axis direction. The lens barrel according to any one of claims 9 to 11.

13. The lens barrel according to any one of claims 1 to 12, An imaging element; An imaging device comprising:

Images