Optical device and imaging apparatus

Abstract

To provide an optical device that is small-sized and makes a movable body movable along an optical axis direction.SOLUTION: An optical device has a stationary barrel and a movable body that is movable along an optical axis direction. The stationary barrel is provided with a plurality of first guide grooves and a plurality of second guide grooves along the optical axis direction. The movable body includes: a stationary roller that is stationary relative to the movable body and a first movable roller the position of which is variable relative to the movable body, which are arranged along the optical axis direction; and a second movable roller and a third movable roller the positions of which are variable relative to the movable body, which are arranged along the optical axis direction. The stationary roller and the second movable roller are arranged on a first circumference of a circle centered on an optical axis. The first movable roller and third movable roller are arranged on a second circumference of a circle centered on the optical axis. The stationary roller and first movable roller are engaged with the first guide grooves, and the second movable roller and third movable roller are engaged with the second guide grooves.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an optical device and an imaging device. [Background technology]

[0002] 2. Description of the Related Art A widely used method for driving a movable body in a lens barrel (optical device) in the optical axis direction is to engage a roller provided on the outer circumferential surface of the movable body with a guide groove provided on the inner circumferential surface of a fixed barrel.

[0003] Patent Document 1 discloses a structure in which a fixed roller journaled on a moving body and a movable roller whose axial position can be moved are engaged with different guide grooves. Figure 10 is a diagram showing the arrangement of the rollers relative to the guide grooves in Patent Document 1. As shown in Figure 10, in the structure in Patent Document 1, two fixed rollers are lined up along the optical axis direction, and one movable roller is arranged so as to be centered between the two fixed rollers in the optical axis direction.

[0004] Patent Document 2 discloses a structure in which an upper roller is placed on a lower roller journaled on a moving body and engaged with a guide groove. In the structure shown in Patent Document 2, the shaft of the upper roller is eccentrically disposed relative to the shaft of the lower roller. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 3765912 [Patent Document 2] Japanese Patent Application Publication No. 10-177129 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the case of the technology disclosed in the above-mentioned Patent Document 1, the posture of the moving body depends on the accuracy of the arrangement of the fixed rollers relative to the guide groove, and it is necessary to improve the accuracy of the parts in order to reduce the inclination of the moving body relative to the optical axis. Also, in order to move the moving body smoothly in a straight line without the rollers rattling, it is preferable that the distance D between the two rollers is long. However, in order to realize smooth straight-line movement of the moving body in Patent Document 1, the distance between the two aligned fixed rollers needs to be further increased, and the moving body becomes large in the optical axis direction. Also, in the case of the technology disclosed in Patent Document 2, the lens barrel becomes large in the radial direction due to the structure in which two rollers are arranged overlapping each other.

[0007] SUMMARY OF THE PRESENT EMBODIMENTS In view of the above, an object of the present invention is to provide an optical device that has a small structure and is capable of moving a movable body along the optical axis direction. [Means for solving the problem]

[0008] In order to achieve the above-mentioned object, a lens barrel as one aspect of the present invention has a fixed cylinder and a movable body movable along an optical axis direction, the fixed cylinder is provided with a plurality of first guide grooves and a plurality of second guide grooves along the optical axis direction, the movable body includes a fixed roller fixed to the movable body and a first movable roller whose position relative to the movable body is variable, arranged along the optical axis direction, and a second movable roller and a third movable roller whose position relative to the movable body is variable, arranged along the optical axis direction, the fixed roller and the second movable roller are arranged on a first circumference centered on the optical axis, the first movable roller and the third movable roller are arranged on a second circumference centered on the optical axis, the fixed roller and the first movable roller engage with the first guide groove, and the second movable roller and the third movable roller engage with the second guide groove. Effect of the Invention

[0009] According to the present invention, it is possible to provide an optical device that has a small structure and is capable of moving a movable body in the optical axis direction. [Brief description of the drawings]

[0010] [Figure 1] 4A to 4C are cross-sectional views of a plane passing through the optical axis of the lens barrel when the moving frame in the first embodiment is at each of the movement ends. [Diagram 2] 2 is an exploded perspective view of each moving frame in the first embodiment, with peripheral parts not shown. FIG. [Diagram 3] 1 is a perspective view showing a state in which the moving frames approach each other in the first embodiment. FIG. [Figure 4] 2 is a cross-sectional view of the lens barrel of the first embodiment as viewed from the object side in the optical axis direction. FIG. [Diagram 5] 4 is a perspective view taken along arrows A and B in FIG. 3. [Figure 6] 4 is a cross-sectional view taken along line C in FIG. 3. [Figure 7] 10A to 10C are cross-sectional views of a plane passing through the optical axis of the lens barrel when the moving frame in the second embodiment is at each of its movement ends. [Figure 8] 11 is a perspective view of a lens barrel showing the position of a light blocking portion provided on a moving body in Example 2. FIG. [Figure 9] FIG. 9 is a perspective view of the lens barrel from FIG. 8 in which a moving body is not shown. [Figure 10] FIG. 13 is a top view showing the arrangement of rollers relative to guide grooves in a conventional example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, the embodiment for carrying out the present invention will be described in detail with reference to the attached drawings. The embodiment described below is one example of a means for realizing the present invention, and should be appropriately modified or changed depending on the configuration of the device to which the present invention is applied and various conditions, and the present invention is not limited to the following embodiment.

[0012] <Example 1> A lens barrel in Example 1 will be described below with reference to Figures 1 to 6. The lens barrel in this example is an optical device having a mechanism for driving a moving body 13 in the direction of an optical axis 10a by a cam drive.

[0013] The lens barrel and a camera (not shown) in this embodiment can form an imaging device (not shown). The camera has an imaging element that receives light from the lens barrel and is configured to capture (take) an image formed through the lens barrel.

[0014] The lens barrel is also provided with a mount (not shown), and in this embodiment, the lens barrel and the mount function as an interchangeable lens. The mount on the lens barrel side is configured to be attachable to a mount on the camera side (not shown), and by attaching it to the camera side mount, it can be physically and electrically connected to the camera. Then, by attaching the mount on the lens barrel side to the camera side mount, they become capable of communicating with each other, and the lens barrel can be fixed to the camera.

[0015] FIG. 1 is an example of a cross-sectional view of a lens barrel in the first embodiment. Specifically, the cross-sectional view is taken along a plane passing through the optical axis 10a and the axis 10b of a lens barrel having moving frames 12a, 12b, and 12c and a moving body 13 that move along the optical axis 10a direction by a cylindrical cam 11 that rotates around another axis 10b parallel to the optical axis 10a. FIG. 1(A) and FIG. 1(B) are cross-sectional views of the lens barrel and show the states of the respective moving ends. Specifically, FIG. 1(A) shows a state in which the moving body 13 is at the moving end on the object side (subject side), and FIG. 1(B) shows a state in which the moving body 13 is at the moving end on the image plane side.

[0016] The moving frame 12a (second moving frame) holds a first lens group 14a composed of a plurality of lenses (optical elements) which are an optical system. The moving frame 12b (first moving frame) holds a second lens group 14b composed of a plurality of lenses (optical elements) which are an optical system. The moving frame 12c (first moving frame) holds a third lens group 14c composed of a plurality of lenses (optical elements) which are an optical system. The moving body 13 holds a fourth lens group 14d composed of a plurality of lenses (optical elements) which are an optical system and which is located closest to the object side. That is, the moving body 13 holds a lens arranged closest to the object side as an optical element.

[0017] The cylindrical cam 11 is held rotatably around the axis 10b relative to the fixed cylinder 15, and has lift grooves 16a, 16b, 16c, and 16d on its outer circumferential surface. These lift grooves 16a to 16d engage with cam followers 17a, 17b, 17c, and 17d provided on the moving frames 12a to 12c and the moving body 13, respectively. That is, the lift groove 16a engages with the cam follower 17a, the lift groove 16b engages with the cam follower 17b, the lift groove 16c engages with the cam follower 17c, and the lift groove 16d engages with the cam follower 17d.

[0018] A driving force transmission member 115 is fixed to the tip of the cylindrical cam 11 that protrudes outward from the fixed cylinder 15, and the cylindrical cam 11 is connected to a driving source (not shown). The cylindrical cam 11 is driven to rotate by the power of the driving source (not shown).

[0019] The movable frames 12a-12c and the movable body 13 are driven in the front-rear direction along the trajectories of the lift grooves 16a-16d by the rotation of the cylindrical cam 11. In this embodiment, three third guide grooves 18a, three second guide grooves 18b, and three first guide grooves 18c are provided on the inner circumferential surface of the fixed barrel 15 along the optical axis 10a direction as guide grooves for linear movement.

[0020] That is, three third guide grooves 18a, three second guide grooves 18b, and three first guide grooves 18c are formed in the fixed barrel 15. The third guide grooves 18a, the second guide grooves 18b, and the first guide grooves 18c are formed taking into consideration tolerances due to manufacturing errors and the like. That is, the third guide grooves 18a, the second guide grooves 18b, and the first guide grooves 18c can each be a guide groove for straight movement substantially parallel to the optical axis 10a.

[0021] Fig. 2 is an exploded perspective view of the moving frames 12a to 12c and the moving body 13 in the first embodiment. Fig. 3 is a perspective view when the moving frames 12a to 12c approach each other. At this time, each moving frame has cutouts 12a2, 12b2, and 12c2 to avoid interference with the extensions of the other moving frames. Specifically, the cutout 12a2 is provided in the moving frame 12a. The cutout 12b2 is provided in the moving frame 12b. The cutout 12c2 is provided in the moving frame 12c.

[0022] The moving frame 12a (second moving frame) has extensions 12a1 extending toward the image surface side along the optical axis 10a (substantially parallel to the optical axis 10a) at three locations on the outer periphery of the moving frame 12a. That is, the moving frame 12a has a plurality of extensions 12a1 extending along the optical axis 10a in a direction opposite to the fourth lens group 14d (the lens closest to the object) held by the moving body 13. Each extension 12a1 has four rollers (second rollers) arranged in a line along the optical axis 10a and fixed to the extension 12a1. A group of rollers including the four rollers (second rollers) fixed to the extension 12a1 is called a roller row 19a. Each roller (second roller) included in the roller row 19a engages with the third guide groove 18a, so that the moving frame 12a is held so as to be linearly movable (movable) along the optical axis 10a. Note that the number of rollers (second rollers) included in the roller row 19a is not limited to the four described above, and may be at least three, or may be four or more.

[0023] The moving frame 12b (first moving frame) has extensions 12b1 extending along the optical axis 10a (substantially parallel to the optical axis 10a) at three locations on the outer periphery of the moving frame 12b toward both the object side and the image plane side. That is, the moving frame 12b has a plurality of extensions 12b1 extending along the optical axis 10a toward the fourth lens group 14d held by the moving body 13 and toward the opposite side to the fourth lens group 14d. Each extension 12b1 has four rollers (first rollers) that are arranged in line along the optical axis 10a and are fixed to the extension 12b1. A group of rollers including the four rollers (first rollers) fixed to the extension 12b1 is referred to as a roller row 19b. Each roller (first roller) included in roller row 19b engages with second guide groove 18b, so that movable frame 12b is held so as to be linearly movable (movable) along optical axis 10a. Note that the number of rollers (first rollers) included in roller row 19b is not limited to the four described above, and may be at least three, or may be four or more.

[0024] The moving frame 12c (first moving frame) has extensions 12c1 extending toward the object side along the optical axis 10a (substantially parallel to the optical axis 10a) at three locations on the outer periphery of the moving frame 12c. That is, the moving frame 12c has a plurality of extensions 12c1 extending toward the fourth lens group 14d held by the moving body 13 along the optical axis 10a. Each extension 12c1 has four rollers (first rollers) arranged in a line along the optical axis 10a and fixed to the extension 12c1. A group of rollers including the four rollers (first rollers) fixed to the extension 12c1 is called a roller row 19c. Each roller (first roller) included in the roller row 19c engages with the first guide groove 18c, so that the moving frame 12c is held so as to be linearly movable (movable) along the optical axis 10a. The number of rollers (first rollers) included in the roller row 19c is not limited to four as described above, but may be at least three, or may be four or more.

[0025] The movable body 13 has extensions (first extensions) 13a extending toward the image surface along the optical axis 10a (substantially parallel to the optical axis 10a) at three locations on the outer periphery of the movable body 13, and extensions (second extensions) 13b at positions different from the extensions 13a. That is, the movable body 13 has a plurality of extensions 13a and a plurality of extensions 13b extending in the direction opposite to the fourth lens group 14d held by the movable body 13 along the optical axis 10a. As described above, the movable body 13 is provided with a plurality of extensions 13a and extensions 13b, and in this embodiment, three of each are provided on the movable body 13.

[0026] Each extension portion 13a is provided with two movable rollers 110 arranged side by side along the optical axis 10a direction and whose positions relative to the movable body 13 can be changed. The movable rollers 110 are supported on the movable body 13 and have movable axial positions (central axis positions can be changed). A group of rollers including the two movable rollers 110 is referred to as an adjustment roller row 112.

[0027] Each extension portion 13b includes one fixed roller 111 fixed to the moving body 13 and one movable roller 110 whose position relative to the moving body 13 is variable, which are arranged side by side along the optical axis 10a direction. The fixed roller 111 is a roller whose axial position is fixed by being fixed to the moving body 13. A group of rollers including this one fixed roller 111 and one movable roller 110 is referred to as a reference roller row 113.

[0028] Hereinafter, the movable rollers 110 included in the reference roller row 113 will be referred to as the first movable rollers 110. Also, the two movable rollers 110 included in the adjustment roller row 112 will be referred to as the second movable rollers 110 and the third movable rollers 110, respectively. Here, the second movable rollers 110 are arranged on the object side along the optical axis 10a direction. The third movable rollers 110 are arranged on the image surface side more than the second movable rollers 110. That is, the second movable rollers 110 are arranged at a position closer to the fourth lens group 14d held by the moving body 13 along the optical axis 10a direction than the third movable rollers 110. Incidentally, the fixed rollers 111 are arranged on the object side along the optical axis 10a direction. The first movable rollers 110 are arranged on the image surface side more than the fixed rollers 111 along the optical axis 10a direction. That is, the fixed rollers 111 are arranged at a position closer to the fourth lens group 14d held by the moving body 13 along the optical axis 10a direction than the first movable rollers 110.

[0029] The second movable roller 110 and the third movable roller 110 included in the adjustment roller row 112 engage with the second guide groove 18b. The fixed roller 111 and the first movable roller 110 included in the reference roller row 113 engage with the first guide groove 18c. In this way, the second movable roller 110 and the third movable roller 110 engage with the second guide groove 18b, and the fixed roller 111 and the first movable roller 110 engage with the first guide groove 18c, so that the movable body 13 is held so as to be linearly movable (movable) in the direction along the optical axis 10a.

[0030] In this embodiment, the second movable roller 110 and the third movable roller 110 included in the adjustment roller row 112 and the fixed roller 111 and the first movable roller 110 included in the reference roller row 113 are considered to be one roller group. In this embodiment, the movable body 13 is held movably in the direction of the optical axis 10a by each roller included in the three (three sets) roller groups.

[0031] As described above, each roller (second roller) included in roller row 19b and the second movable roller 110 and the third movable roller 110 included in adjustment roller row 112 engage with second guide groove 18b. Also, each roller (second roller) included in roller row 19c and the fixed roller 111 and the first movable roller 110 included in reference roller row 113 engage with first guide groove 18c.

[0032] In this manner, in this embodiment, the second guide groove 18b can be used by both the rollers included in adjustment roller row 112 and the rollers included in roller row 19b. Furthermore, the first guide groove 18c can be used by both the rollers included in reference roller row 113 and the rollers included in roller row 19c. This makes it possible to hold movable body 13 in a linear manner without increasing the number of guide grooves formed in fixed barrel 15 according to the rollers corresponding to the roller rows.

[0033] In this embodiment, an example has been described in which each roller included in the adjustment roller row 112 engages with the second guide groove 18b, and each roller included in the reference roller row 113 engages with the first guide groove 18c, but this combination is not limiting. For example, it may be configured so that each roller included in the adjustment roller row 112 engages with the first guide groove 18c, and each roller included in the reference roller row 113 engages with the second guide groove 18b.

[0034] The reference roller row 113 may include one or more fixed rollers 111 arranged along the optical axis 10a direction and fixed to the movable body 13, and one or more movable rollers 110 whose positions are variable relative to the movable body 13. The adjustment roller row 112 may include two or more movable rollers arranged along the optical axis 10a direction and whose positions are variable relative to the movable body 13.

[0035] The detailed configurations and effects of the second movable roller 110 and the third movable roller 110 included in the adjustment roller row 112 and the fixed roller 111 and the first movable roller 110 included in the reference roller row 113 will be described below with reference to Figures 4, 5, and 6.

[0036] Fig. 4 is an example of a cross-sectional view of the lens barrel 100 in this embodiment as viewed from the object side along the optical axis 10a. Fig. 5 is an example of an arrow view as viewed from direction A and direction B in Fig. 4. Specifically, Fig. 5 shows a state in which each roller of the adjustment roller row 112 is engaged with the second guide groove 18b, and each roller of the reference roller row 113 is engaged with the first guide groove 18c.

[0037] As shown in FIG. 5, the second movable roller 110 and the third movable roller 110 included in the adjustment roller row 112, and the fixed roller 111 and the first movable roller 110 included in the reference roller row 113 are disposed at equal positions in the direction of the optical axis 10a.

[0038] In this embodiment, the rollers included in the reference roller row 113 and the rollers included in the adjustment roller row 112 are arranged so that the arrangement intervals in the optical axis 10a direction are equal. That is, the fixed roller 111 and the first movable roller 110 included in the reference roller row 113, and the second movable roller 110 and the third movable roller 110 included in the adjustment roller row 112 are arranged in the extension section 13a and the extension section 13b so as to be lined up at an interval D in the optical axis 10a direction. As a result, the fixed roller 111 and the second movable roller 110 are arranged on a first circumference centered on the optical axis 10a, and the first movable roller 110 and the third movable roller 110 are arranged on a second circumference different from the first circumference centered on the optical axis 10a. Note that the intervals between the rollers do not have to be completely equal, and may be intervals that take into account, for example, manufacturing errors or setting tolerances.

[0039] The interval D can be, for example, the interval (distance) between the central axis of one roller and the central axis of another roller arranged along the optical axis 10a. The interval D between the fixed roller 111 and the first movable roller 110 is the interval between the central axis position of the fixed roller 111 and the central axis position of the first movable roller 110. The interval D between the second movable roller 110 and the third movable roller 110 is the interval between the central axis position of the second movable roller 110 and the central axis position of the third movable roller 110. The center axis position of the first to third movable rollers is the central axis position of the male thread portion 110a described later.

[0040] In this way, by disposing the fixed roller 111 and the first movable roller 110 on the extension portion 13b, and the second movable roller 110 and the third movable roller 110 on the extension portion 13a, respectively, the length (distance) between these rollers in the direction of the optical axis 10a is only the interval D. That is, the arrangement interval between the fixed roller 111 and the first movable roller 110 in the direction of the optical axis 10a and the arrangement interval between the second movable roller 110 and the third movable roller 110 are the same interval (same distance). With this configuration, the moving body 13 in the lens barrel 100 of this embodiment can be reduced in length in the direction of the optical axis 10a while maintaining smooth linear movement compared to the structure in the conventional example shown in FIG.

[0041] Fig. 6 is an example of a cross-sectional view taken along the cutting line C in Fig. 4. Specifically, this is a cross-sectional view showing the configuration of the fixed roller 111 and the first movable roller 110 included in the reference roller row 113. Here, the fixed roller 111 is fixed to the movable body 13 by being screwed into the extension portion 13b of the movable body 13. The first movable roller 110 has a roller portion 110b that engages with the first guide groove 18c, and a male screw portion 110a for fixing the movable roller. The second movable roller 110 and the third movable roller 110 also have a roller portion 110b and a male screw portion 110a.

[0042] The first movable roller 110 is disposed relative to a through hole 13c formed in the extension portion 13b of the movable body 13. When the first movable roller 110 is disposed in the through hole 13c, the male thread portion 110a passes through the through hole 13c and partially protrudes from the inner peripheral surface side. Then, a nut (fastening member) 114 is attached to the male thread portion 110a protruding from the inner peripheral surface side and fastened, thereby fixing the movable body 13. The second movable roller 110 and the third movable roller 110 are also disposed relative to the through hole 13c formed in the extension portion 13a of the movable body 13, and fixed to the movable body 13 in the same manner as above.

[0043] The central axis 110d of the roller portion 110b is eccentric with respect to the central axis 110c of the male thread portion 110a, so that the position of the roller portion 110b can be changed by rotating the movable roller 110 around the central axis 110c of the male thread portion 110a.

[0044] When the movable body 13 is assembled into the fixed cylinder 15, the first movable roller 110 is eccentrically adjusted relative to the fixed roller 111 so that the alignment of the fixed roller 111 and the first movable roller 110 included in the reference roller row 113 in the direction of the optical axis 10a is made parallel to the optical axis 10a. This makes it possible to align the positions of the fixed roller 111 and the first movable roller 110 included in the reference roller row 113 in the circumferential direction of the optical axis. Thereafter, the second movable roller 110 and the third movable roller 110 included in the adjustment roller row 112 are eccentrically adjusted to position each roller included in the adjustment roller row 112.

[0045] In this embodiment, the fixed rollers 111 and the first movable rollers 110 included in the reference roller row 113 also function as an adjustment structure for adjusting the alignment of the rollers. In this way, by providing an adjustment structure that allows the alignment of the rollers to be adjusted, it is possible to reduce the inclination of the movable body 13 with respect to the optical axis 10a without increasing the precision of the parts.

[0046] As described above, the lens barrel of this embodiment does not require high component precision and can reduce the overall length in the direction of optical axis 10a (the length in the direction of optical axis 10a). This extends the drivable distance L1 until movable body 13 interferes with movable frame 12b and movable frame 12c, improving the degree of freedom in optical design.

[0047] <Example 2> In the first embodiment, the movable body 13 is an optical component that holds the fourth lens group 14d. In the second embodiment, the movable body 23 serves as a light blocking component (light blocking member) that blocks stray light. That is, the movable body 23 in the second embodiment functions as a blocking body that does not hold optical elements such as lenses and has a function of blocking harmful light.

[0048] Hereinafter, the lens barrel in the second embodiment will be described with reference to Fig. 7. Note that the second embodiment differs from the first embodiment in that the configuration of the moving body is different, and a description of the other equivalent configurations and effects will be omitted.

[0049] FIG. 7 is an example of a cross-sectional view of a plane passing through the optical axis 20a of the optical system of the lens barrel when the moving frame 22a in the second embodiment is at each moving end. Specifically, it is a cross-sectional view cut on a plane passing through the optical axis 20a and the axis 20b of the optical system of the lens barrel having the moving frames 22a, 22b, and 22c and the moving body 23 driven in the optical axis 20a direction by the cylindrical cam 21 rotating around another axis 20b parallel to the optical axis 20a. FIG. 7(A) and FIG. 7(B) show the states of the respective moving ends. Specifically, FIG. 7(A) shows the state in which the moving frame 22a is at the moving end on the object side, and FIG. 7(B) shows the state in which the moving frame 22a is at the moving end on the image plane side.

[0050] Fig. 8 is a perspective view of the lens barrel showing the position of light blocking portion 23a provided on movable body 13 in Example 2. Fig. 9 is a perspective view of the lens barrel with movable body 13 not shown in Fig. 8. Specifically, it is a perspective view showing gap 25 between fixed cylinder 24 and movable frame 22a with movable body 23 not shown.

[0051] When the moving frame 22a is on the object side as shown in Fig. 7(A), Fig. 8, and Fig. 9, a gap 25 is generated between the notch 22a1 provided in the moving frame 22a and the fixed barrel 24. Therefore, harmful light enters the lens barrel by passing through the harmful light range Ra. In the moving body 23 in the second embodiment, a light shielding portion 23a is provided at a position in phase with the notch 22a1 provided in the moving frame 22a to be able to block (shield) this harmful light. The light shielding portion 23a in this embodiment is able to block at least the light entering through the gap 25 between the notch 22a1 and the fixed barrel 24.

[0052] 7(B), when the moving frames 22a to 22c are close to each other inside the fixed cylinder 24, the moving body 23 moves to a position that avoids the effective light beam range Rb and does not interfere with the moving frames 22b and 22c, that is, by the retraction distance L2. The retraction distance L2 is restricted in that it must be a distance at which the moving body 23 does not interfere with the moving frames 22b and 22c, in addition to the necessary distance increasing as the effective light beam range Rb expands.

[0053] Therefore, by applying a configuration (holding structure) similar to that of the moving body 13 in the first embodiment to the moving body 23 in the second embodiment, the length of the moving body 23 in the optical axis 20a direction can be reduced, and the retraction distance L2 can be extended. Therefore, in addition to the effect of the first embodiment, the moving body 23 in the second embodiment can retract without blocking the effective light range Rb, which is larger than the conventional range.

[0054] Although the 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 the gist of the present invention.

[0055] The disclosure of this embodiment includes the following configuration.

[0056] (Configuration 1) A fixed cylinder; a movable body that is movable along an optical axis direction, The fixed barrel is provided with a plurality of first guide grooves and a plurality of second guide grooves aligned along the optical axis direction, The moving body is A fixed roller that is fixed to the movable body and a first movable roller whose position is variable with respect to the movable body are arranged along the optical axis direction; a second movable roller and a third movable roller arranged along the optical axis direction and whose positions with respect to the movable body are variable, the fixed roller and the second movable roller are arranged on a first circumference centered on an optical axis, the first movable roller and the third movable roller are arranged on a second circumference centered on the optical axis, An optical device, characterized in that the fixed roller and the first movable roller engage with the first guide groove, and the second movable roller and the third movable roller engage with the second guide groove.

[0057] (Configuration 2) The optical device according to configuration 1, wherein the distance between the fixed roller and the first movable roller in the optical axis direction is the same as the distance between the second movable roller and the third movable roller.

[0058] (Configuration 3) The movable body holds an optical element, the fixed roller is disposed at a position closer to the optical element than the first movable roller in the optical axis direction, 3. The optical device according to configuration 1 or 2, wherein the second movable roller is disposed at a position closer to the optical element in the optical axis direction than the third movable roller.

[0059] (Configuration 4) the movable body includes a first extension portion extending along the optical axis direction to an opposite side to the optical element, The optical device according to configuration 3, wherein the second movable roller and the third movable roller are provided on the first extension portion.

[0060] (Configuration 5) the movable body includes a second extension portion extending in a direction opposite to the optical element along the optical axis direction at a position different from the first extension portion, The optical device according to configuration 4, wherein the fixed roller and the first movable roller are provided on the second extension portion.

[0061] (Configuration 6) The optical device according to configuration 5, wherein the movable body includes a plurality of the first extension portions and a plurality of the second extension portions.

[0062] (Configuration 7) a first moving frame that is movable along the optical axis direction, the first moving frame includes three first rollers that are arranged along the optical axis direction and are fixed to the first moving frame, 7. The optical device according to any one of configurations 1 to 6, wherein the three first rollers engage with the first guide groove or the second guide groove.

[0063] (Configuration 8) a second moving frame that is a moving frame different from the first moving frame and is movable along the optical axis direction; The fixed barrel is provided with a plurality of third guide grooves aligned along the optical axis direction, the second moving frame includes three second rollers that are arranged along the optical axis direction and are fixed to the second moving frame, The optical device according to configuration 7, wherein the three second rollers engage with the third guide groove.

[0064] (Configuration 9) the second moving frame has a notch for avoiding interference with the first moving frame, 9. The optical device according to configuration 8, wherein the movable body has a light blocking portion that is arranged at a position in phase with the notch portion.

[0065] (Configuration 10) 10. The optical device according to configuration 9, wherein the light blocking portion is capable of blocking at least light entering through a gap between the notch portion and the fixed barrel.

[0066] (Configuration 11) An optical device described in any one of configurations 1 to 10, characterized in that the movable body is held movably along the optical axis direction by the fixed roller, the first movable roller, the second movable roller, and the third movable roller.

[0067] (Configuration 12) The movable body includes one or more fixed rollers that are fixed to the movable body and one or more movable rollers whose positions are variable with respect to the movable body, the fixed rollers being disposed along the optical axis direction, 12. The optical device according to any one of configurations 1 to 11, comprising: two or more movable rollers arranged along the optical axis direction, the position of which is variable relative to the movable body.

[0068] (Configuration 13) 13. An imaging device comprising: the optical device according to any one of configurations 1 to 12; and an imaging element that receives light from the optical device. [Explanation of symbols]

[0069] 100 Lens barrel (optical device) 13 Mobile 15 Fixed tube 18a 3rd guide groove 18b Second guide groove 18c First guide groove 110 Movable roller 111 Fixed roller

Claims

1. A fixed cylinder; a movable body that is movable along an optical axis direction, The fixed barrel is provided with a plurality of first guide grooves and a plurality of second guide grooves aligned along the optical axis direction, The moving body is a fixed roller that is fixed to the movable body and a first movable roller that is variable in position relative to the movable body, the fixed roller and the first movable roller being disposed along the optical axis direction; a second movable roller and a third movable roller arranged along the optical axis direction and whose positions with respect to the movable body are variable, the fixed roller and the second movable roller are arranged on a first circumference centered on an optical axis, the first movable roller and the third movable roller are arranged on a second circumference centered on the optical axis, an optical device, characterized in that the fixed roller and the first movable roller engage with the first guide groove, and the second movable roller and the third movable roller engage with the second guide groove;

2. 2 . The optical device according to claim 1 , wherein a distance between the fixed roller and the first movable roller and a distance between the second movable roller and the third movable roller in the optical axis direction are the same.

3. The movable body holds an optical element, the fixed roller is disposed at a position closer to the optical element than the first movable roller in the optical axis direction, The optical device according to claim 1 , wherein the second movable roller is disposed at a position closer to the optical element in the optical axis direction than the third movable roller.

4. the movable body includes a first extending portion extending along the optical axis direction to an opposite side to the optical element, The optical device according to claim 3 , wherein the second movable roller and the third movable roller are provided on the first extension portion.

5. the movable body includes a second extension portion extending in a direction opposite to the optical element along the optical axis direction at a position different from the first extension portion, The optical device according to claim 4 , wherein the fixed roller and the first movable roller are provided on the second extension portion.

6. The optical device according to claim 5 , wherein the movable body includes a plurality of the first extending portions and a plurality of the second extending portions.

7. a first moving frame that is movable along the optical axis direction, the first moving frame includes three first rollers arranged along the optical axis direction and fixed to the first moving frame, 2. The optical device according to claim 1, wherein the three first rollers are engaged with the first guide groove or the second guide groove.

8. a second moving frame that is a moving frame different from the first moving frame and is movable along the optical axis direction; The fixed barrel is provided with a plurality of third guide grooves aligned along the optical axis direction, the second moving frame includes three second rollers arranged along the optical axis direction and fixed to the second moving frame, 8. The optical device according to claim 7, wherein the three second rollers are engaged with the third guide groove.

9. the second moving frame has a notch portion for avoiding interference with the first moving frame, The optical device according to claim 8 , wherein the movable body has a light blocking portion disposed at a position in phase with the notch portion.

10. 10. The optical device according to claim 9, wherein the light blocking portion is capable of blocking light entering through a gap between the notch portion and the fixed barrel.

11. 2 . The optical device according to claim 1 , wherein the movable body is held by the fixed roller, the first movable roller, the second movable roller, and the third movable roller so as to be movable along the optical axis direction.

12. The movable body includes one or more fixed rollers that are fixed to the movable body and one or more movable rollers whose positions are variable with respect to the movable body, the fixed rollers being disposed along the optical axis direction, 2. The optical device according to claim 1, further comprising: two or more movable rollers arranged along the optical axis direction, the positions of which are variable relative to the movable body.

13. 13. An imaging device comprising: the optical device according to claim 1; and an imaging element that receives light from the optical device.

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