Lens device and imaging apparatus

Abstract

To provide a lens device that ensures sufficient strength without reducing driving efficiency despite its small size.SOLUTION: A lens barrel 1 comprises: a base 601; a lens barrel unit 404 that holds a lens 401 and is held by the base movably in an optical axis direction OD; and a driving mechanism 800 that drives the lens barrel unit. The driving mechanism has a coil 424a that is fixed to the lens barrel unit, and a driving mechanism part 801 that is held by the base. The base is provided with an opening 601s into which the lens barrel unit is inserted. When seen from the side of the opening with respect to the optical axis direction, a portion of the base and a portion of the driving mechanism part overlap each other so that the portion of the base is arranged on the front of the driving mechanism part.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a lens device and an imaging device that have a movable member that holds a lens. [Background technology]

[0002] Lens devices used in imaging devices (optical instruments) such as video cameras and digital cameras employ a drive mechanism that drives a lens and a lens barrel that holds the lens in the optical axis direction. The use of a large lens in a lens device enables improved optical performance. To move larger lenses than conventional lenses, drive mechanisms that generate drive force using, for example, a magnet and a coil have been proposed. Patent Document 1 discloses a drive mechanism that is provided on the outer periphery of the lens barrel that holds the lens inside the lens device. Patent Document 1 also discloses that a larger drive mechanism can be accommodated inside the lens device without increasing the size of the lens device by offsetting the center of the coil outward from the center of the magnet. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-64284 [Patent Document 2] International Publication No. 2023 / 048001 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the drive mechanism disclosed in Patent Document 1, the line connecting the centers of the magnets arranged on both sides of the coil is offset from the center of the coil, reducing the efficiency of the drive mechanism. To attach the drive mechanism to the lens device without reducing its efficiency, it is necessary to provide a large opening in the retaining barrel that holds the drive mechanism, as shown in Patent Document 2. However, providing a large opening in the retaining barrel makes it difficult to ensure the strength of the retaining barrel, which can cause the lens to tilt during assembly, when the temperature environment changes, or when it is subjected to impact, potentially reducing optical performance. Therefore, to ensure the strength of the retaining barrel, it is necessary to increase the outer diameter of the retaining barrel, which increases the size of the lens device.

[0005] The present invention provides a lens device that is small in size yet ensures sufficient strength without reducing drive efficiency. [Means for solving the problem]

[0006] A lens device according to one aspect of the present invention comprises a retaining tube, a movable member that holds a lens and is held by the retaining tube so as to be movable in the optical axis direction, and a drive mechanism that drives the movable member, wherein the drive mechanism has a coil fixed to the movable member and a magnetic material portion held by the retaining tube, the retaining tube having an opening through which the movable member is inserted, and when viewed from the side of the opening in the optical axis direction, the portion of the retaining tube overlaps with a portion of the magnetic material portion so that the portion of the retaining tube is positioned in front of the magnetic material portion.

[0007] a third magnetic material portion disposed on one side of the first magnetic material portion in relation to the optical axis direction and magnetically joining the first magnetic material portion and the second magnetic material portion; and a fourth magnetic material portion disposed on the other side of the first magnetic material portion in relation to the optical axis direction and magnetically joining the first magnetic material portion and the second magnetic material portion. The lens device according to another aspect of the present invention comprises: a retaining tube; a movable member that holds a lens and is held by the retaining tube so as to be movable in the optical axis direction; a coil fixed to the movable member; a first magnetic material portion disposed inside the coil and spaced apart from the inner periphery of the coil; a plurality of magnets disposed facing the outer periphery of the coil and spaced apart from the outer periphery of the coil; a plurality of second magnetic material portions that respectively hold the plurality of magnets; a third magnetic material portion disposed on one side of the first magnetic material portion in relation to the optical axis direction and magnetically joining the first magnetic material portion and the second magnetic material portion; and a fourth magnetic material portion disposed on the other side of the first magnetic material portion in relation to the optical axis direction and magnetically joining the first magnetic material portion and the second magnetic material portion. The movable member is characterized by having a first cover portion disposed on one side of the coil in relation to the optical axis direction and covering one end of the coil; and a second cover portion disposed on the other side of the coil in relation to the optical axis direction and covering the other end of the coil. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a lens device that is small in size yet ensures sufficient strength without reducing drive efficiency. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view of an imaging device according to a first embodiment. [Figure 2] FIG. 3 is a perspective view of a fourth group unit according to the first embodiment. [Figure 3] FIG. 4 is a plan view of a fourth group unit according to the first embodiment. [Figure 4] FIG. 2 is a perspective view of a base that holds a drive mechanism according to the first embodiment. [Figure 5] FIG. 2 is an explanatory diagram of a drive mechanism part of the first embodiment. [Figure 6] FIG. 2 is a rear view of the base in which the drive mechanism of the first embodiment is incorporated. [Figure 7] FIG. 3 is a schematic diagram showing the relationship between a drive mechanism and a connecting portion in the first embodiment. [Figure 8]5A and 5B are schematic diagrams illustrating the relationship between the contact positions of the back yoke, the front base yoke, and the rear base yoke in the first embodiment. [Figure 9] FIG. 3 is a cross-sectional view showing the relationship between the coil and the lens barrel base in the first embodiment. [Figure 10] FIG. 10 is a perspective view of a drive mechanism according to a second embodiment. [Figure 11] FIG. 11 is a schematic diagram showing the relationship between a drive mechanism and a connecting portion in a third embodiment. [Figure 12] FIG. 10 is a schematic diagram showing the relationship between a drive mechanism and a connecting portion in a fourth embodiment. [Figure 13] FIG. 10 is a schematic diagram showing the relationship between a drive mechanism and a connecting portion in a fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. [Example]

[0011] FIG. 1 is a cross-sectional view of an imaging device 10 of a first embodiment. The imaging device 10 has a lens barrel (lens device) 1 and a camera body 2. The camera body 2 has an imaging element 3 that captures an image formed by the lens barrel 1. The camera body 2 is configured to be able to capture an image formed through the lens barrel 1. The lens barrel 1 is provided with a mount 4. The lens barrel 1 is fixed to the camera body 2 by being connected to a mount (not shown) provided on the camera body 2. The lens barrel 1 is an interchangeable lens that is removably attached to the camera body 2. The lens barrel 1 does not necessarily have to be an interchangeable lens, and may be fixedly attached to the camera body 2 or may be configured integrally with the camera body 2.

[0012] Lens barrel 1 has, in order from the object side (left side in FIG. 1) to the image side (right side in FIG. 1), lens 101, lens 201, lens 301, lens 401, and lens 501 as optical elements. Lens barrel 1 has first group unit 100, second group unit 200, third group unit 300, fourth group unit 400, and fifth group unit 500, which hold lens 101, lens 201, lens 301, lens 401, and lens 501, respectively. First group unit 100, second group unit 200, third group unit 300, fourth group unit 400, and fifth group unit 500 are held by base 601.

[0013] The second group unit 200 and the fourth group unit 400 are each guided by a guide bar (not shown) and constitute a focus group that can be driven and controlled by a drive mechanism during focusing. When the operator rotates the operating ring 5, the positional relationship between the second group unit 200 and the fourth group unit 400 in the direction along the optical axis 7 (hereinafter referred to as the optical axis direction OD) changes, thereby changing the focus position of the lens barrel 1. Each drive mechanism is driven and controlled by the main CPU 6. The drive mechanism of the second group unit 200 is a well-known configuration using a vibrator, so details will be omitted. The drive mechanism of the fourth group unit 400 is a voice coil motor (VCM), details of which will be described later. The main CPU 6 of the lens barrel 1 performs the above-mentioned control by communicating with a main CPU (not shown) provided in the camera body 2.

[0014] 2(a) and 2(b) are perspective views of the fourth group unit 400 of Example 1. FIG. 3 is a plan view of the fourth group unit 400 of Example 1. A lens 401 held in the fourth group unit 400 is fixed to a lens barrel 402. The lens barrel 402 is held by a lens barrel base 403 so as to be adjustable by adjustment rollers 405a, 405b, 405c, 405d, 405e, and 405f. The lens barrel 402 and the lens barrel base 403 constitute a lens barrel unit 404 (moving member). Adjustments made by adjustment rollers 405a, 405b, 405c, 405d, 405e, and 405f are well known, and therefore will not be described here.

[0015] Lens-barrel unit 404 holds lens 401 and is held by base (holding barrel) 601 so as to be movable in the optical axis direction OD. A guide unit 406 is fixed to lens-barrel unit 404, and is guided by a main guide bar 602 fixed to base 601. By adjusting a ball bearing provided in guide unit 406 as a rotating element that rolls relative to main guide bar 602, the tilt component and guide direction of lens-barrel unit 404 relative to base 601 can be adjusted.

[0016] A ball bearing, which allows barrel unit 404 to be guided by sub-guide bar 603 fixed to base 601, is rotatably held in barrel unit 404 by shaft screw 420. With this configuration, the eccentricity component of lens 401 with respect to optical axis 7 of lens barrel 1 is adjusted. Barrel unit 404 is urged toward sub-guide bar 603 by a sub-magnet (not shown) fixed to sub-yoke 423 so that the ball bearing comes into contact with sub-guide bar 603. Main guide bar 602 and sub-guide bar 603 each have one end held by base 601, and the other end held by fifth group barrel 502 inside fifth group unit 500.

[0017] The barrel unit 404 holds coils 424a and 424b that constitute a drive mechanism for moving the barrel unit 404 in the optical axis direction OD relative to the base 601. The barrel unit 404 holds a flexible cable 425 for passing current through the coils 424a and 424b. The flexible cable 425 forms a U-turn portion between the base 601 and the barrel base 403, and is configured so that the barrel base 403 can move in the optical axis direction OD (guide direction) relative to the base 601. The position of the barrel unit 404 in the optical axis direction OD is detected using a scale 415 as position detection means, and a drive mechanism described below is used to control the barrel unit 404 so that it is held at any position.

[0018] Next, the configuration of the magnetic circuit of the drive mechanism will be described. In this embodiment, the object side will be referred to as the front side, and the image side will be referred to as the rear side. The center yoke (first magnetic portion) 606a is disposed inside the coil 424a, spaced apart from the inner periphery (inner peripheral surface) of the coil 424a (with a clearance (gap) between it and the inner periphery of the coil 424a), and is fixed to the base 601. In front of and behind the center yoke 606a in the optical axis direction OD, a front base yoke 605a and a rear base yoke 609a are attracted by VCM magnets (multiple magnets) 607a and 607b (described later) and are in contact with the center yoke 606a.

[0019] The front base yoke (third magnetic material portion) 605a is disposed on the front side (one side) of the center yoke 606a in relation to the optical axis direction OD, and magnetically joins the center yoke 606a to the back yokes 608a and 608b (plurality of second magnetic material portions). The front base yoke 605a is disposed in front of the center yoke 606a in relation to the optical axis direction OD, and abuts against the base 601 in the optical axis direction OD. The front base yoke 605a is fixed to the base 601 with screws (fixing members) 701a and 701b ( FIG. 4 ) from the side where the center yoke 606a is disposed. The rear base yoke (fourth magnetic material portion) 609a is disposed on the rear side (the other side) of the center yoke 606a in relation to the optical axis direction OD, and magnetically joins the center yoke 606a to the back yokes 608a and 608b.

[0020] The front base yoke 605a has flat portions 605a1 and 605a2 that are approximately the same distance from the optical axis 7 on both sides of the optical axis 7 in the circumferential direction CD perpendicular to the optical axis direction OD. Similarly, the rear base yoke 609a has flat portions 609a1 and 609a2 that are approximately the same distance from the optical axis 7 on both sides of the optical axis 7 in the circumferential direction CD perpendicular to the optical axis direction OD. The flat portions 605a1, 605a2, 609a1, and 609a2 of the front base yoke 605a and the rear base yoke 609a are approximately parallel. The VCM magnets 607a and 607b are magnetically attracted and fixed to the coil sides of the back yokes 608a and 608b (plurality of second magnetic material portions). The VCM magnets 607a and 607b are arranged so that the same pole faces the coil 424a. VCM magnets 607a and 607b are disposed facing the outer periphery of coil 424a and spaced apart from the outer periphery of coil 424a. A first contact surface 608a1 and a second contact surface 608a2 of back yoke 608a to which VCM magnet 607a is attracted are attracted to and held by a flat surface 605a1 of front base yoke 605a and a flat surface 609a1 of rear base yoke 609a. Back yoke 608b to which VCM magnet 607b is attracted is attracted to and held by a flat surface 605a2 of front base yoke 605a and a flat surface 609a2 of rear base yoke 609a. A magnetic circuit is formed with the above configuration.

[0021] In this embodiment, the back yokes 608a and 608b, the front base yoke 605a, and the rear base yoke 609a are separate bodies, but they do not necessarily have to be separate bodies. For example, the back yoke 608a and the front base yoke 605a may be integrally formed, the back yoke 608b and the front base yoke 605a may be integrally formed, or the back yokes 608a and 608a and the front base yoke 605a may be integrally formed. Also, for example, the center yoke 606a, the front base yoke 605a, and the back yokes 608a and / or 608b may be integrally formed.

[0022] Although details are omitted, a similar configuration is adopted for coil 424b. By passing a current through each of coils 424a and 424b, lens barrel unit 404 can be moved in the guide direction. The detailed principles and control are well known techniques and will not be described here.

[0023] FIG. 4 is a perspective view of a base 601 that holds a driving mechanism 801 according to the first embodiment. FIGS. 5(a) and 5(b) are explanatory diagrams of the driving mechanism 801 according to the first embodiment. The driving mechanism 800 that drives the barrel unit 404 includes a driving mechanism 801 and a coil 424a. The driving mechanism 801 includes a front base yoke 605a, a center yoke 606a, VCM magnets 607a and 607b, back yokes 608a and 608b, and a rear base yoke 609a. FIG. 5(a) shows the front base yoke 605a, the center yoke 606a, and the rear base yoke 609a of the driving mechanism 801 that are attached to the base 601. FIG. 5(b) shows the driving mechanism 801 attached to the base 601. The front base yoke 605a is fixed to the base 601 with screws (fixing members) 701a and 701b, which are screwed from the rear to the front in the optical axis direction OD. In other words, the screws 701a and 701b can be fixed from the side (rear) of the opening 601s through which the barrel unit 404 is inserted into the base 601, eliminating the need to provide fixing portions for fixing the screws 701a and 701b from the front of the base 601. In other words, a fixing portion for the barrel (third group unit 300), which is assembled from the front, can be provided on the base 601 in front of the drive mechanism unit 801. Furthermore, a guide bar for guiding the movable group (second group unit 200) can be provided on the base 601 in front of the drive mechanism unit 801. This eliminates the need to arrange other barrel components around the fixing portions, making it possible to reduce the size of the base 601 in the direction perpendicular to the optical axis 7 (hereinafter referred to as the radial direction RD).

[0024] As shown in FIG. 3, the center yoke 606a has a front cylindrical portion 606c, a central cylindrical portion 606e, and a rear cylindrical portion 606d. The front cylindrical portion 606c is provided in front of the central cylindrical portion 606e, and the rear cylindrical portion 606d is provided behind the central cylindrical portion 606e. The central cylindrical portion 606e is disposed to penetrate the inside of the coil 424a and has a diameter that separates it from the inner periphery of the coil 424a with a clearance. The diameters of the front cylindrical portion 606c and the rear cylindrical portion 606d are smaller than the diameter of the central cylindrical portion 606e.

[0025] The front base yoke 605a has a hole 605e. The front cylindrical portion 606c passes through the hole 605e in the front base yoke 605a and is inserted into a hole (not shown) in the base 601, thereby determining the position of the center yoke 606a in the optical axis direction OD. The center yoke 606a abuts against the front base yoke 605a at a step where the diameter of the central cylindrical portion 606e differs from the diameter of the front cylindrical portion 606c.

[0026] The coil 424a is fixed to the barrel base 403 and assembled to the center yoke 606a. As shown in FIG. 2(a), the coil 424a is held between a front holding portion (first cover portion) 403c and a rear holding portion (second cover portion) 403d provided on the barrel base 403. The front holding portion 403c and the rear holding portion 403d are provided on the outer periphery of the barrel base 403 and extend outward in the radial direction RD from the outer periphery of the barrel base 403. The front holding portion 403c has a front hole 403a. The rear holding portion 403d has a rear hole 403b. The center yoke 606a extends through the front hole 403a of the front holding portion 403c, the coil 424a, and the rear hole 403b of the rear holding portion 403d. A detailed structure will be described later. Since the lens barrel base 403 is held by the main guide bar 602 and sub guide bar 603 of the base 601 and the center yoke 606a is held by the base 601, the coil 424a is held apart from the center yoke 606a.

[0027] With the coil 424a assembled to the center yoke 606a, the rear base yoke 609a can be assembled to the center yoke 606a from the rear side of the base 601 through the opening 601s. The rear base yoke 609a is provided with a hole 609e. As will be described in detail later, the rear cylindrical portion 606d of the center yoke 606a is inserted into the hole 609e of the rear base yoke 609a, and the rear base yoke 609a is assembled to the center yoke 606a. The rear cylindrical portion 606d of the center yoke 606a is fitted into and held in a hole (not shown) provided in the fifth group barrel 502, which is fixed to the base 601 on the rear side of the fourth group unit 400.

[0028] 5(a) shows a state in which the front base yoke 605a, center yoke 606a, and rear base yoke 609a are attached to the base 601 as described above. A VCM magnet 607a and back yoke 608a unit, and a VCM magnet 607b and back yoke 608b unit are assembled into the base 601 in this state, thereby forming a drive mechanism 801 as shown in FIG.

[0029] The base 601 has a hole (outer diameter hole) 601c (shown by a dotted line in FIG. 4) formed in the outer periphery of the base 601. The hole 601c is large enough to allow the VCM magnets 607a and 607b and the back yokes 608a and 608b to pass through. In the first embodiment, the VCM magnet 607a and the back yoke 608a in a unit state can be installed inside the base 601 from outside the outer periphery of the base 601 through the hole 601c. The back yokes 608a and 608b can be seen through the hole 601c from outside the outer periphery of the base 601. When the hole 601c is viewed from outside the outer periphery of the base 601 in a radial direction RD perpendicular to the optical axis direction OD, the hole 601c is larger than the VCM magnet 607a and the back yoke 608a in a unit state. 5(a), the VCM magnet 607a and back yoke 608a can be assembled as a unit through the hole 601c from outside the outer periphery of the base 601. The VCM magnets 607a and 607b face the outer periphery of the coil 424a and are spaced apart from the outer periphery of the coil 424a.

[0030] According to the present embodiment, there is no need to insert the entire drive mechanism unit 801 through the opening 601s, and therefore the opening 601s in the base 601 can be made smaller than the size (outer diameter) of the space in which the drive mechanism unit 801 is disposed, as viewed in the optical axis direction OD. In this embodiment, the opening 601s, through which the fourth group unit 400 is inserted in the base 601, is provided on the rear side (image side). However, the opening 601s may be provided on the front side (object side), and the fourth group unit 400 may be inserted into the base 601 from the front side (object side).

[0031] FIG. 6 is a rear view of the base 601 incorporating the drive mechanism 801 of the first embodiment. The base 601 has a connecting portion 601b that connects the outer periphery of the opening 601s to close it. When viewed from the rear of the base 601 in the optical axis direction OD, the connecting portion 601b is positioned outside the coil 424a provided in the barrel base 403. Therefore, the opening 601s allows the coil 424a to pass through. The connecting portion 601b may be formed integrally with the base 601 and may constitute a part of the base 601. When viewed from the rear side (the other side) of the center yoke 606a in the optical axis direction OD, the connecting portion 601b overlaps with the back yokes 608a and 608b so that the connecting portion 601b is positioned in front of the back yokes 608a and 608b. Since the connecting portion 601b connects the outside of the opening 601s, the base 601 forms an annular portion that completely surrounds the opening 601s, thereby ensuring the strength of the base 601.

[0032] FIG. 7 is a schematic diagram showing the relationship between the drive mechanism 801 and the connecting portion 601b in the first embodiment. As shown in FIG. 7, when viewed from the rear in the optical axis direction OD, the connecting portion 601b overlaps the back yokes 608a and 608b. This configuration makes it possible to provide an annular portion surrounding the opening 601s without providing an opening 601s with an outer diameter larger than the outer diameter of the space in which the back yokes 608a and 608b are disposed. In other words, the drive mechanism 801 can be held without increasing the diameter of the base 601. In other words, the lens barrel 1 can be made smaller.

[0033] When viewed in the radial direction RD from outside the outer periphery of the base 601, the connecting portion 601b overlaps the rear cylindrical portion 606d. Therefore, it is possible to reduce the size of the base 601 in the radial direction RD without increasing the size of the base 601 in the optical axis direction OD.

[0034] Next, the configuration of the drive mechanism 801 will be described in more detail. As shown in FIG. 5(a), the base 601 is provided with a restricting surface 601e and a restricting surface 601g on the front inner side with respect to the optical axis direction OD. The restricting surface 601e abuts against the inner surface of one end of the front base yoke 605a and the inner surface of one end of the back yoke 608a, and restricts the positions of the front base yoke 605a and the back yoke 608a in the radial direction RD perpendicular to the optical axis direction OD. The restricting surface 601g abuts against the inner surface of the other end of the front base yoke 605a and the inner surface of one end of the back yoke 608b, and restricts the positions of the front base yoke 605a and the back yoke 608b in the radial direction RD perpendicular to the optical axis direction OD.

[0035] The base 601 is provided with protrusions 601i, 601j, and 601k that protrude toward the rear side on the outer side of the front side in the optical axis direction OD (FIGS. 4 and 5). The front base yoke 605a is disposed between the restriction surfaces 601e and 601g and the protrusions 601i and 601j. The restriction surfaces 601e and 601g abut against the inner side of the front base yoke 605a, and the protrusions 601i and 601j abut against the outer side of the front base yoke 605a, thereby positioning the front base yoke 605a in the radial direction RD.

[0036] A recess 605d is provided on the outer surface of the front base yoke 605a. The protrusion 601k of the base 601 fits into the recess 605d of the front base yoke 605a, thereby positioning the front base yoke 605a in the circumferential direction CD. In this way, because a positioning portion is provided on the outer side of the front base yoke 605a, the front base yoke 605a can be positioned without reducing the magnetic efficiency of the front base yoke 605a.

[0037] The position of the front base yoke 605a relative to the base 601 is determined by the restricting surface 601e, the restricting surface 601g, the protrusion 601i, the protrusion 601j, and the protrusion 601k, which serve as positioning portions. The front cylindrical portion 606c of the center yoke 606a is inserted into both a hole (not shown) in the base 601 and a hole 605e ( FIG. 3 ) in the front base yoke 605a. The front cylindrical portion 606c (one end) of the center yoke 606a is held by a hole (not shown) in the base 601. Here, if the hole 605e in the front base yoke 605a is smaller than the hole (not shown) in the base 601, the clearance between the central cylindrical portion 606e of the center yoke 606a and the inner periphery of the coil 424a can be reduced, thereby increasing the driving efficiency.

[0038] As shown in FIG. 6, a connecting portion 601b formed by a part of the base 601 is provided on the outer side of the rear base yoke 609a in the radial direction RD. The connecting portion 601b at least partially covers the rear base yoke 609a. As shown in FIG. 5(a), when the hole portion 601c is viewed in the radial direction RD from the outside of the base 601, the connecting portion 601b and the rear base yoke 609a overlap with each other so that the connecting portion 601b is positioned in front of the rear base yoke 609a. As shown in FIG. 6, if the hole 609e of the rear base yoke 609a, into which the rear cylindrical portion 606d of the center yoke 606a is inserted, is a circular hole, the rear base yoke 609a will rotate around the rear cylindrical portion 606d. Therefore, restricting portions 601d (FIG. 6) are provided on the inner side of the connecting portion 601b, which abut against the rear base yoke 609a on both sides of the hole 609e in the circumferential direction CD. The restricting portions 601d provided on the connecting portion 601b abut against the outer side of the rear base yoke 609a, thereby restricting rotation of the rear base yoke 609a about the rear cylindrical portion 606d. In other words, the drive mechanism 801 can be stably incorporated into the base 601.

[0039] As shown in FIG. 5(a), the base 601 is provided with a restricting surface 601f and a restricting surface 601h on the rear inner side with respect to the optical axis direction OD. The restricting surface 601f is provided rearward of the restricting surface 601e with the VCM magnet 607a sandwiched therebetween. The restricting surface 601h is provided rearward of the restricting surface 601g with the VCM magnet 607b sandwiched therebetween. The restricting surface 601f abuts against the inner surface of the other end of the back yoke 608a. The restricting surface 601h abuts against the inner surface of the other end of the back yoke 608b. The back yoke 608a abuts against the restricting surfaces 601e and 601f (plurality of second restricting portions), thereby positioning the back yoke 608a in the radial direction RD. The back yoke 608b abuts against the restricting surfaces 601g and 601h (plurality of second restricting portions), thereby positioning the back yoke 608b in the radial direction RD. This configuration allows the front base yoke 605a and / or the rear base yoke 609a to be smaller, and the size of the opening 601s (FIG. 6) to be reduced. By efficiently arranging the necessary components and reducing the size of the opening 601s, it becomes possible to reduce the size of the lens barrel 1 in the radial direction RD.

[0040] The rear cylindrical portion 606d of the center yoke 606a is inserted into both a hole (not shown) in the fifth group barrel (holding member) 502 and a hole 609e (FIG. 6) in the rear base yoke 609a. The rear cylindrical portion 606d (the other end) of the center yoke 606a is held by a hole (not shown) in the fifth group barrel 502. The fifth group barrel 502 is fixed to the base 601 by screwing screws 703a and 703b (FIG. 4) into screw holes (fixing portions) 601l and 601m provided in the base 601. As shown in FIGS. 4 and 6, when viewed from the rear side in the optical axis direction OD, the screw hole 601l is provided in the base 601 so that the screw hole 601l is positioned in front of the back yoke 608a and overlaps with the back yoke 608a. Similarly, when viewed from the rear side in the optical axis direction OD, screw hole 601m is provided in base 601 so that screw hole 601m is located in front of back yoke 608b and overlaps with back yoke 608b. Screw holes 601l and 601m are provided in positions close to center yoke 606a. Since fifth group barrel 502, which serves as a holding member, can be fixed to base 601 in a position close to center yoke 606a, which is heavy, center yoke 606a can be held stably.

[0041] As shown in FIG. 5(a), the base 601 is provided with restriction surfaces 601n and 601o, and 601p and 601q (plurality of first restriction portions) arranged opposite each other in the optical axis direction OD. As shown in FIG. 5(b), the back yoke 608a is arranged between the restriction surfaces 601n and 601o. The position of the back yoke 608a in the optical axis direction OD is restricted by the restriction surfaces 601n and 601o. The restriction surfaces 601n and 601o function as positioning portions that position the back yoke 608a in the optical axis direction OD. As shown in FIG. 5(b), the back yoke 608b is arranged between the restriction surfaces 601p and 601q. The position of the back yoke 608b in the optical axis direction OD is restricted by the restriction surfaces 601p and 601q. The restriction surfaces 601p and 601q function as positioning portions that position the back yoke 608b in the optical axis direction OD.

[0042] As described above, the position of the back yoke 608a in the optical axis direction OD is determined by the restricting surfaces 601n and 601o provided on the base 601. The position of the coil 424a is determined by the position of the fourth group unit 400 that holds the coil 424a. The position of the fourth group unit 400 is determined by the specifications of the optical system. According to this embodiment, the back yoke 608a to which the VCM magnet 607a is attracted is positioned by the restricting surfaces 601n and 601o provided on the base 601, thereby reducing assembly errors between the VCM magnet 607a and the coil 424a. In other words, it is possible to suppress a decrease in the drive efficiency of the drive mechanism near the ends of the movement range of the fourth group unit 400, compared to determining the position of the back yoke 608a by the front base yoke 605a and the rear base yoke 609a, for example. A similar effect can be obtained for the back yoke 608b.

[0043] FIG. 8 is a schematic diagram illustrating the relationship between the contact positions of the back yoke 608a, front base yoke 605a, and rear base yoke 609a in the first embodiment. The back yoke 608a is magnetically attracted by the VCM magnet 607a and contacts the front base yoke 605a and rear base yoke 609a. Referring to FIG. 3, a first contact surface 608a1 of the back yoke 608a contacts the front base yoke 605a. A second contact surface 608a2 of the back yoke 608a contacts the rear base yoke 609a. An attraction surface 608a3 of the back yoke 608a is attracted to the VCM magnet 607a. The first contact surface 608a1, second contact surface 608a2, and attraction surface 608a3 of the back yoke 608a are provided on the same plane. This same plane is referred to as a contact surface 608c (FIGS. 3 and 8).

[0044] As shown in FIG. 8 , a line 701 is a straight line passing through the center M1 of the VCM magnet 607a (one magnet) and the center C1 of the center yoke 606a. The line 701 intersects with the abutment surface 608c. In this embodiment, when viewed along the optical axis direction OD, the line 701 is approximately perpendicular to the abutment surface 608c and passes through the abutment surface 608c. The attraction force generated in the back yoke 608a toward the center yoke 606a passes substantially along the line 701 toward the center yoke 606a. With this configuration, even when the back yoke 608a abuts against one surface, which is the flat portion 605a1 of the front base yoke 605a, and is attracted to the back yoke 608a, the back yoke 608a is held by the front base yoke 605a without falling toward the coil 424a. For example, to prevent the back yoke 608a from tipping over, it is conceivable to provide a recess at one end of the back yoke 608a and a protrusion on the flat surface 605a1 of the front base yoke 605a, with the protrusion fitting into the recess in the back yoke 608a. However, according to this embodiment, the back yoke 608a can be held in contact with one surface of the flat surface 605a1 of the front base yoke 605a, eliminating the need to provide a protrusion on the back yoke 608a side of the front base yoke 605a. As a result, the circumferential width of the front base yoke 605a can be reduced, which in turn reduces the size of the opening 601s in the base 601, allowing for efficient arrangement of necessary components and enabling the miniaturization of the lens barrel 1. The same applies to the rear base yoke 609a.

[0045] 5(b), the back yokes 608a and 608b are fixed with an adhesive at one or more adhesive spots 702 between the front base yoke 605a and / or the rear base yoke 609a. The back yokes 608a and 608b are held in place by the magnetic attraction between the VCM magnets 607a and 607b and the center yoke 606a, but are held more firmly by being fixed with an adhesive. It is preferable that the back yokes 608a and 608b be fixed with an adhesive to at least one of the base 601, the front base yoke 605a, and the rear base yoke 609a.

[0046] FIG. 9 is a cross-sectional view showing the relationship between the coil 424a and the barrel base 403 in the first embodiment. The method of holding the coil 424a by the barrel base 403 will be described with reference to FIGS. 2 and 9. As described above, the coil 424a is held between a front holding portion 403c and a rear holding portion 403d provided on the barrel base 403. The front holding portion 403c (first cover) is disposed on the front side (one side) of the coil 424a with respect to the optical axis direction OD and covers the front end portion (one end) of the coil 424a. The rear holding portion 403d (second cover) is disposed on the rear side (the other side) of the coil 424a with respect to the optical axis direction OD and covers the rear end portion (the other end) of the coil 424a. The front holding portion 403c has a front hole (first hole) 403a through which the center yoke 606a passes (FIGS. 2 and 4). The rear holding portion 403d has a rear hole (second hole) 403b through which the center yoke 606a passes (FIG. 4). The coil 424a is fixed with an adhesive in a front adhesive groove 403e provided in the front holding portion 403c, a rear adhesive groove 403f provided in the rear holding portion 403d, and an adhesive groove 403g provided on the optical axis 7 side of the coil 424a.

[0047] A hole diameter 403h (first inner diameter) of the front hole 403a is equal to or smaller than an inner diameter 424c of the coil 424a. Furthermore, when viewed in the optical axis direction OD, the circle that forms the front hole 403a is located within the circle that forms the inner diameter 424c of the coil 424a. A hole diameter (second inner diameter) of the rear hole 403b is also equal to or smaller than the inner diameter 424c of the coil 424a, and when viewed in the optical axis direction OD, the circle that forms the rear hole 403b is located within the circle that forms the inner diameter 424c of the coil 424a. In other words, holes having a hole diameter that is equal to or smaller than the inner diameter 424c of the coil 424a are provided in front of and behind the coil 424a. With this configuration, even if the fourth group unit 400 is tilted with respect to the center yoke 606a, the center yoke 606a abuts against the front hole 403a or the rear hole 403b before the coil 424a. Generally, the coil 424a and the center yoke 606a may come into contact with each other and become disengaged during assembly or when subjected to an impact such as being dropped. For this reason, in conventional technology, the clearance between the coil 424a and the center yoke 606a is increased to a certain extent. However, increasing the clearance reduces the drive efficiency of the drive mechanism. In contrast, according to this embodiment, the center yoke 606a abuts against the front hole 403a or the rear hole 403b, so force is not applied only to the coil 424a. Therefore, the clearance between the coil 424a and the center yoke 606a can be reduced to increase drive efficiency. In other words, the drive mechanism can be made more compact, allowing the lens barrel 1 to be made smaller. [Example]

[0048] Hereinafter, a description will be given of Example 2. The imaging device 10 of Example 2 has the same structure as the imaging device 10 of Example 1 except for the drive mechanism unit 802, so a description of the imaging device 10 will be omitted. Hereinafter, the drive mechanism unit 802 of Example 2 will be described with reference to FIG.

[0049] FIG. 10 is a perspective view of a drive mechanism 802 according to the second embodiment. The drive mechanism 800 for driving the lens barrel unit 404 includes a drive mechanism 802 and a coil 1424a. The drive mechanism 802 includes a base yoke 1605, a center yoke 1606a, VCM magnets 1607a and 1607b, and a rear base yoke 1609a. The base yoke 1605 is U-shaped. The base yoke 1605 includes a front base yoke portion 1605a, and a first back yoke portion (first side) 1605b and a second back yoke portion (second side) 1605c extending rearward from both ends of the front base yoke portion 1605a. The front base yoke portion 1605a, which serves as a third magnetic body portion, and the first back yoke portion 1605b and the second back yoke portion 1605c, which serve as multiple second magnetic body portions, are integrally formed. The front base yoke portion 1605a is disposed in front of the center yoke 1606a in relation to the optical axis direction OD and in contact with the base 1601 in the optical axis direction OD. The front base yoke portion 1605a is fixed to the base 1601 by screwing screws (fixing members) 1701a and 1701b from the side (rear side) where the center yoke 1606a is disposed toward the front side. The front base yoke portion (third magnetic material portion) 1605a magnetically joins the center yoke 1606a to the first back yoke portion 1605b and the second back yoke portion 1605c (plurality of second magnetic material portions).

[0050] The first back yoke part 1605b and the second back yoke part 1605c are disposed facing each other with the coil 1424a sandwiched therebetween. The VCM magnets 1607a and 1607b are magnetically attracted to and fixed to the coil sides of the first back yoke part 1605b and the second back yoke part 1605c, respectively. The VCM magnets 1607a and 1607b are disposed so that the same pole faces the coil 1424a. The VCM magnets 1607a and 1607b face the outer periphery of the coil 1424a and are disposed at a distance from the outer periphery of the coil 1424a.

[0051] The center yoke (first magnetic body portion) 1606a is disposed inside the coil 1424a, spaced apart from the inner periphery (inner peripheral surface) of the coil 1424a (with a clearance (gap) between it and the inner periphery of the coil 1424a), and is fixed to the base 1601. A rear base yoke (fourth magnetic body portion) 1609a is disposed on the rear side (other side) of the center yoke 1606a in the optical axis direction OD. The rear base yoke 1609a is attracted by the magnetic force of VCM magnets (magnets) 1607a and 1607b, and is in contact with the base yoke 1605 and the center yoke 1606a. The rear base yoke 1609a magnetically connects the center yoke 1606a to the first back yoke portion 1605b and the second back yoke portion 1605c. The magnetic circuit is configured as described above.

[0052] As in the first embodiment, the base 1601 has a connecting portion 1601b that connects the outer periphery of the opening 1601s so as to close it. The connecting portion 1601b is preferably formed integrally with the base 1601 and constitutes a part of the base 1601. Because the connecting portion 1601b connects the outside of the opening 1601s, the base 1601 forms an annular portion that completely surrounds the opening 1601s, thereby ensuring the strength of the base 1601. When viewed from the rear side (the other side) of the center yoke 1601a in the optical axis direction OD, the connecting portion 1601b is positioned in front of the first back yoke portion 1605b and the second back yoke portion 1605c. The connecting portion 1601b overlaps with portions of the first back yoke portion 1605b and the second back yoke portion 1605c. That is, as in the first embodiment, by providing the connecting portion 1601b, it is possible to reduce the size of the lens barrel 1 while ensuring the strength of the base 1601.

[0053] The base 1601 has a hole (outer diameter hole) 1601c, indicated by a dotted line in FIG. 10 , formed in the outer periphery of the base 1601. The hole 1601c is large enough to allow the U-shaped base yoke 1605 and VCM magnets 1607a and 1607b to pass through. The first back yoke part 1605b and the second back yoke part 1605c can be seen through the hole 1601c from outside the outer periphery of the base 1601. In the second embodiment, when viewed from outside the base 1601, the hole 1601c is approximately the same size as or larger than the base yoke 1605 to which the VCM magnets 1607a and 1607b are attached. That is, the base yoke 1605 to which the VCM magnets 1607a and 1607b are attached can be assembled as a unit into the base 1601 from the outside of the outer periphery of the base 1601 through the hole 1601c.

[0054] As in the first embodiment, the connecting portion 1601b, which is formed by a portion of the base 1601, is disposed outside the rear base yoke 1609a in the radial direction RD, which is perpendicular to the optical axis direction OD. When the hole 1601c is viewed in the radial direction RD from the outside of the base 1601, the connecting portion 1601b and the rear base yoke 1609a overlap so that the connecting portion 1601b is disposed in front of the rear base yoke 1609a. This allows the base 1601 to be made smaller without increasing the size of the base 1601 in the optical axis direction OD. [Example]

[0055] Hereinafter, a description will be given of Example 3. The imaging device 10 of Example 3 has the same structure as the imaging device 10 of Example 1 except for the drive mechanism unit 803, so a description of the imaging device 10 will be omitted. Hereinafter, the drive mechanism unit 803 of Example 3 will be described with reference to FIG.

[0056] FIG. 11 is a schematic diagram showing the relationship between a driving mechanism 803 and a connecting portion 2601b in the third embodiment. The driving mechanism 800 that drives the barrel unit 404 includes a driving mechanism 803 and a coil 2424a. The driving mechanism 803 includes a front base yoke (not shown), a center yoke 2606a, VCM magnets 2607a and 2607b, back yokes 2608a and 2608b, and a rear base yoke (not shown). The center yoke (first magnetic body portion) 2606a is disposed inside the coil 2424a, spaced apart from the inner periphery (inner peripheral surface) of the coil 2424a with a clearance (gap) between them, and is fixed to the base 2601. As shown in FIG. 11, the back yokes 2608a and 2608b (plurality of second magnetic body portions) are disposed in a V-shape. VCM magnets 2607a and 2607b are magnetically attracted and fixed to the coil sides of back yokes 2608a and 2608b, respectively, with the same magnetic poles facing each other, and are arranged in a V shape. VCM magnets 2607a and 2607b face the outer periphery of coil 2424a and are arranged at a distance from the outer periphery of coil 2424a.

[0057] When viewed from the rear side (the other side) of the center yoke 2606a in the optical axis direction OD, the connecting portion 2601b is disposed closer to the back yokes 2608a and 2608b, and the connecting portion 2601b overlaps with portions of the back yokes 2608a and 2608b. In the third embodiment, the opening 2601s can be made smaller than the size (outer diameter) of the space in which the back yokes 2608a and 2608b are disposed, as viewed in the optical axis direction OD, and it is possible to provide an annular portion in the base 2601 that surrounds the opening 2601s. In other words, the drive mechanism 803 can be held without increasing the diameter of the base 2601. This allows the lens barrel 1 to be made smaller. [Example]

[0058] Hereinafter, a fourth embodiment will be described. The imaging device 10 of the fourth embodiment has the same structure as the imaging device 10 of the first embodiment except for the driving mechanism unit 804, and therefore a description of the imaging device 10 will be omitted. Hereinafter, the driving mechanism unit 804 of the fourth embodiment will be described with reference to FIG.

[0059] 12 is a schematic diagram showing the relationship between a driving mechanism 804 and a connecting portion 3601b in the fourth embodiment. The driving mechanism 800 that drives the lens barrel unit 404 includes a driving mechanism 804 and a coil 3424a. The driving mechanism 804 includes a front base yoke (not shown), a center yoke 3606a, VCM magnets 3607a and 3607b, back yokes 3608a and 3608b, and a rear base yoke (not shown). The center yoke (first magnetic body portion) 3606a is disposed inside the coil 3424a and spaced apart from the inner periphery (inner peripheral surface) of the coil 3424a (with a clearance (gap) between it and the inner periphery of the coil 3424a), and is fixed to the base 3601. The VCM magnets 3607a and 3607b face the outer periphery of the coil 3424a and are spaced apart from the outer periphery of the coil 3424a. 12, back yokes 3608a and 3608b (plurality of second magnetic material portions) are disposed opposite each other with coil 3424a sandwiched therebetween. Back yoke 3608a to which VCM magnet 3607a is attracted and back yoke 3608b to which VCM magnet 3607b is attracted are disposed opposite center yoke 3606a. Center C1 of center yoke 3606a is disposed outward in the radial direction RD from center M1 of VCM magnet 3607a and center M2 of VCM magnet 3607b. In other words, the distance from optical axis 7 to center C1 of center yoke 3606a is greater than the distance from optical axis 7 to straight line C2 connecting center M1 of VCM magnet 3607a and center M2 of VCM magnet 3607b.

[0060] When viewed from the rear side (the other side) of the center yoke 3606a in the optical axis direction OD, the connecting portion 3601b is disposed in front of the back yokes 3608a and 3608b, and the connecting portion 3601b overlaps with portions of the back yokes 3608a and 3608b. In the fourth embodiment, too, the opening 3601s can be made smaller than the size (outer diameter) of the space in which the back yokes 3608a and 3608b are disposed, as viewed in the optical axis direction OD, making it possible to provide the base 3601 with an annular portion that completely surrounds the opening 3601s. In other words, the drive mechanism 804 can be held without increasing the diameter of the base 3601. This means that the lens barrel 1 can be made smaller. [Example]

[0061] Hereinafter, a fifth embodiment will be described. The imaging device 10 of the fifth embodiment has the same structure as the imaging device 10 of the first embodiment except for the driving mechanism unit 805, and therefore a description of the imaging device 10 will be omitted. Hereinafter, the driving mechanism unit 805 of the fifth embodiment will be described with reference to FIG.

[0062] FIG. 13 is a schematic diagram showing the relationship between a drive mechanism 805 and a connecting portion 4601b in the fifth embodiment. A drive mechanism 800 that drives the barrel unit 404 includes a drive mechanism 805 and a coil 4424a. The drive mechanism 805 includes a front base yoke (not shown), a magnet unit 4606a, side yokes 4608a and 4608b, and a rear base yoke (not shown). The barrel base 403 of the fourth group unit 400 holds the coil 4424a, as in the first embodiment. The magnet unit 4606a is disposed inside the coil 4424a, spaced apart from the inner periphery (inner peripheral surface) of the coil 4424a (with a clearance (gap) between it and the inner periphery of the coil 4424a), and is fixed to the base 4601. The magnet unit 4606a has magnetic poles in the optical axis direction OD and is composed of multiple magnets. The magnet unit 4606a may be configured, for example, by arranging a plurality of cylindrical magnets in the optical axis direction OD, or may be configured from a single magnet.

[0063] The side yokes (plurality of first magnetic material portions) 4608a and 4608b face the outer periphery of the coil 4424a and are spaced apart from the outer periphery of the coil 4424a. A front base yoke (not shown) as a second magnetic material portion is arranged on the front side (one side) of the magnet unit 4606a in the optical axis direction OD, and the front base yoke magnetically joins the magnet unit 4606a and the side yokes 4608a and 4608b. A rear base yoke (not shown) as a third magnetic material portion is arranged on the rear side (the other side) of the magnet unit 4606a in the optical axis direction OD, and the rear base yoke magnetically joins the magnet unit 4606a and the side yokes 4608a and 4608b. The side yokes 4608a and 4608b may be further fixed to the front base yoke and / or the rear base yoke with an adhesive.

[0064] The front base yoke (not shown) is disposed in front of the magnet unit 4606a in contact with the base 4601 in the optical axis direction OD. The front base yoke is fixed to the base 4601 from the rear side in the optical axis direction OD with fixing members such as screws. The base 4601 has a connecting portion 4601b that connects to close the outer periphery of the opening 4601s. The connecting portion 4601b is preferably formed integrally with the base 4601 and constitutes a part of the base 4601. When viewed from the rear side of the magnet unit 4606a in the optical axis direction OD, the connecting portion 4601b is disposed forward of the side yokes 4608a and 4608b, and the connecting portion 4601b overlaps with parts of the side yokes 4608a and 4608b. In the fifth embodiment, too, the opening 4601s can be made smaller than the size (outer diameter) of the space in which the side yokes 4608a and 4608b are disposed when viewed in the optical axis direction OD, and an annular portion that completely surrounds the opening 4601s can be provided in the base 4601. In other words, the drive mechanism 805 can be held without increasing the diameter of the base 4601. This allows the lens barrel 1 to be made smaller.

[0065] In the above-described first to fifth embodiments, the radial direction RD restriction surfaces of the back yoke are provided within the range of the optical axis direction in which the front and rear base yokes are disposed. However, the radial direction RD restriction surfaces of the back yoke may be provided on the outside of the front and rear base yokes in the optical axis direction. For example, protrusions (stepped portions) are provided that extend from the outer radial direction RD portions of both ends of the back yoke in the optical axis direction outward from the front and rear base yokes in the optical axis direction. The radial direction RD position of the back yoke may be restricted by abutting the inner radial direction RD surfaces of these protrusions (stepped portions) against restriction surfaces provided on the base.

[0066] In the first to fifth embodiments, the back yoke (side yoke) may be further fixed to the front and rear base yokes with an adhesive, or the back yoke (side yoke) may be fixed to the base with an adhesive. In the first to fifth embodiments, the coil is formed in a circular shape, but the same effect can be obtained even if the coil is formed in a rectangular shape.

[0067] In the imaging device 10 of this embodiment, the lens barrel 1 is an interchangeable lens that is removably attached to the camera body 2. However, the imaging device may also be a camera in which the lens barrel and the camera body are integrated.

[0068] The disclosure of this embodiment includes the following configuration. (Configuration 1) A lens device comprising: a retaining barrel; a movable member that holds a lens and is held by the retaining barrel so as to be movable in the optical axis direction; and a drive mechanism that drives the movable member, wherein the drive mechanism has a coil fixed to the movable member and a magnetic material portion held by the retaining barrel, the retaining barrel having an opening through which the movable member is inserted, and when viewed from the opening side with respect to the optical axis direction, the portion of the retaining barrel overlaps with a portion of the magnetic material portion so that the portion of the retaining barrel is positioned in front of the magnetic material portion. (Configuration 2) The magnetic body portion includes a first magnetic body portion disposed inside the coil and spaced apart from the inner periphery of the coil, a plurality of magnets facing the outer periphery of the coil and spaced apart from the outer periphery of the coil, a plurality of second magnetic body portions each holding the plurality of magnets, a third magnetic body portion disposed on one side of the first magnetic body portion in the optical axis direction and magnetically joining the first magnetic body portion and the plurality of second magnetic body portions, and a third magnetic body portion disposed on the other side of the first magnetic body portion in the optical axis direction and magnetically joining the first magnetic body portion and the plurality of second magnetic body portions. The lens device described in configuration 1 is characterized in that it has a fourth magnetic material portion that magnetically joins the first magnetic material portion and the plurality of second magnetic material portions, the third magnetic material portion is arranged in contact with the retaining barrel in the optical axis direction on one side of the first magnetic material portion with respect to the optical axis direction, and when viewed from the other side of the first magnetic material portion with respect to the optical axis direction, the portion of the retaining barrel overlaps with the plurality of second magnetic material portions so that the portion of the retaining barrel is arranged in front of the plurality of second magnetic material portions. (Configuration 3) The lens device according to Configuration 2, wherein the holding tube has holes formed in the outer periphery thereof so that the plurality of second magnetic material portions can be seen. (Configuration 4) The lens device according to configuration 3, wherein the hole portion has a size that allows the plurality of magnets and the plurality of second magnetic material portions to pass therethrough. (Configuration 5) A lens device described in configuration 3 or 4, characterized in that when the hole portion is viewed from outside the retaining barrel in a direction perpendicular to the optical axis direction, the portion of the retaining barrel overlaps with the fourth magnetic material portion so that the portion of the retaining barrel is positioned in front of the fourth magnetic material portion. (Configuration 6) The lens device described in any one of configurations 2 to 5, characterized in that the retaining barrel has a plurality of first regulating portions that respectively regulate the positions of the plurality of second magnetic material portions in the optical axis direction. (Configuration 7) A lens device described in any one of configurations 2 to 6, characterized in that the retaining barrel has a plurality of second regulating portions that respectively regulate the positions of the plurality of second magnetic material portions in a direction perpendicular to the optical axis direction. (Structure 8) A lens device described in any one of structures 2 to 7, characterized in that one end of the first magnetic material portion is held by the holding tube, the lens device further has a holding member that holds the other end of the first magnetic material portion, and a fixing portion that fixes the holding member to the holding tube overlaps with the second magnetic material portion so that the fixing portion is positioned in front of the second magnetic material portion when viewed from the other side of the first magnetic material portion in the optical axis direction. (Configuration 9) A lens device described in any one of configurations 2 to 8, characterized in that the plurality of second magnetic material portions are fixed to at least one of the retaining tube, the third magnetic material portion, and the fourth magnetic material portion by adhesive. (Configuration 10) A lens device described in any one of configurations 2 to 9, characterized in that the third magnetic material portion is fixed to the retaining tube by a fixing member from the side where the first magnetic material portion is arranged. (Configuration 11) The lens device according to any one of configurations 2 to 10, wherein the plurality of second magnetic body portions, the third magnetic body portion, and the fourth magnetic body portion are separate bodies. (Structure 12) A lens device described in any one of structures 2 to 11, characterized in that when viewed along the optical axis direction, a straight line connecting the center of one of the plurality of magnets and the center of the first magnetic material portion intersects a first contact surface where one of the plurality of second magnetic material portions holding the one magnet contacts the third magnetic material portion, and a second contact surface where the one second magnetic material portion contacts the fourth magnetic material portion. (Configuration 13) The lens device according to any one of configurations 2 to 10, wherein the plurality of second magnetic body portions and the third magnetic body portion are integral with each other. (Structure 14) A lens device comprising: a retaining barrel; a movable member that holds a lens and is held by the retaining barrel so as to be movable in the optical axis direction; a coil fixed to the movable member; a first magnetic material portion arranged inside the coil and spaced apart from the inner periphery of the coil; a plurality of magnets arranged opposite the outer periphery of the coil and spaced apart from the outer periphery of the coil; a plurality of second magnetic material portions that respectively hold the plurality of magnets; a third magnetic material portion arranged on one side of the first magnetic material portion with respect to the optical axis direction and magnetically joining the first magnetic material portion and the plurality of second magnetic material portions; and a fourth magnetic material portion arranged on the other side of the first magnetic material portion with respect to the optical axis direction and magnetically joining the first magnetic material portion and the plurality of second magnetic material portions, wherein the retaining barrel has a hole on its outer periphery so that the plurality of second magnetic material portions can be seen. (Structure 15) A lens device comprising: a retaining tube; a movable member that holds a lens and is held by the retaining tube so as to be movable in the optical axis direction; a coil fixed to the movable member; a first magnetic material portion arranged inside the coil and spaced apart from the inner periphery of the coil; a plurality of magnets arranged opposite the outer periphery of the coil and spaced apart from the outer periphery of the coil; a plurality of second magnetic material portions that respectively hold the plurality of magnets; a third magnetic material portion arranged on one side of the first magnetic material portion with respect to the optical axis direction and magnetically joining the first magnetic material portion and the plurality of second magnetic material portions; and a fourth magnetic material portion arranged on the other side of the first magnetic material portion with respect to the optical axis direction and magnetically joining the first magnetic material portion and the plurality of second magnetic material portions, wherein the movable member has a first cover portion arranged on one side of the coil with respect to the optical axis direction and covering one end of the coil; and a second cover portion arranged on the other side of the coil with respect to the optical axis direction and covering the other end of the coil. (Configuration 16) The lens device described in Configuration 15, characterized in that the first cover portion has a first hole portion through which the first magnetic material portion passes, the second cover portion has a second hole portion through which the first magnetic material portion passes, and a first inner diameter of the first hole portion and a second inner diameter of the second hole portion are smaller than the inner diameter of the coil. (Configuration 17) A holding tube, a moving member that holds a lens and is held by the holding tube so as to be movable in the optical axis direction, a coil fixed to the moving member, a magnet unit that is arranged inside the coil and spaced apart from the inner periphery of the coil, a plurality of first magnetic body parts that face the outer periphery of the coil and are spaced apart from the outer periphery of the coil, a second magnetic body part that is arranged on one side of the magnet unit in the optical axis direction and that magnetically joins the magnet unit and the plurality of first magnetic body parts, and a second magnetic body part that is arranged on one side of the magnet unit in the optical axis direction and that magnetically joins the magnet unit and the plurality of first magnetic body parts. a third magnetic material portion arranged on the other side of the lens unit and magnetically joining the magnet unit and the plurality of first magnetic material portions, wherein the second magnetic material portion is arranged in contact with the retaining tube in the optical axis direction on one side of the magnet unit with respect to the optical axis direction, and when viewed from the other side of the magnet unit with respect to the optical axis direction, the portion of the retaining tube overlaps with the plurality of first magnetic material portions so that the portion of the retaining tube is arranged in front of the plurality of first magnetic material portions. (Structure 18) A lens device comprising: a retaining tube; a movable member that holds a lens and is held by the retaining tube so as to be movable in the optical axis direction; a coil fixed to the movable member; a magnet unit arranged inside the coil and spaced apart from the inner periphery of the coil; a plurality of first magnetic material portions arranged opposite the outer periphery of the coil and spaced apart from the outer periphery of the coil; a second magnetic material portion arranged on one side of the magnet unit with respect to the optical axis direction and magnetically joining the magnet unit and the plurality of first magnetic material portions; and a third magnetic material portion arranged on the other side of the magnet unit with respect to the optical axis direction and magnetically joining the magnet unit and the plurality of first magnetic material portions, wherein the retaining tube has a hole on its outer periphery so that the plurality of first magnetic material portions are visible. (Structure 19) A lens device comprising: a retaining tube; a movable member that holds a lens and is held by the retaining tube so as to be movable in the optical axis direction; a coil fixed to the movable member; a magnet unit arranged inside the coil and spaced apart from the inner periphery of the coil; a plurality of first magnetic material portions arranged opposite the outer periphery of the coil and spaced apart from the outer periphery of the coil; a second magnetic material portion arranged on one side of the magnet unit with respect to the optical axis direction and magnetically joining the magnet unit and the plurality of first magnetic material portions; and a third magnetic material portion arranged on the other side of the magnet unit with respect to the optical axis direction and magnetically joining the magnet unit and the plurality of first magnetic material portions, wherein the movable member comprises: a first cover portion arranged on one side of the coil with respect to the optical axis direction and covering one end of the coil; and a second cover portion arranged on the other side of the coil with respect to the optical axis direction and covering the other end of the coil. (Configuration 20) The lens device described in any one of configurations 1 to 19, characterized in that the lens device is an interchangeable lens that is removably attached to the main body of an imaging device having an imaging element that captures an image formed by the lens device. (Configuration 21) An imaging device comprising: the lens device according to any one of configurations 1 to 20; and an imaging element that captures an image formed by the lens device. [Explanation of symbols]

[0069] 1 Lens barrel 401 Lens 404 Telescope Unit 424a coil 601 Base 601b Joint 601s opening 800 Drive Mechanism 801 Drive mechanism OD optical axis direction

Claims

1. A holding cylinder; a moving member that holds a lens and is held by the holding barrel so as to be movable in the optical axis direction; a drive mechanism that drives the moving member; Equipped with The drive mechanism includes: a coil fixed to the moving member; a magnetic body portion held by the holding cylinder; and the retaining cylinder is provided with an opening into which the moving member is inserted, A lens device characterized in that, when viewed from the opening side in the optical axis direction, a portion of the retaining barrel overlaps with a portion of the magnetic material portion so that the portion of the retaining barrel is positioned in front of the magnetic material portion.

2. The magnetic material portion is a first magnetic portion disposed inside the coil and spaced apart from an inner circumferential portion of the coil; a plurality of magnets arranged facing an outer periphery of the coil and spaced apart from the outer periphery of the coil; a plurality of second magnetic portions that respectively hold the plurality of magnets; a third magnetic body portion disposed on one side of the first magnetic body portion in the optical axis direction and magnetically joining the first magnetic body portion and the plurality of second magnetic body portions; a fourth magnetic body portion that is disposed on the other side of the first magnetic body portion in the optical axis direction and magnetically joins the first magnetic body portion and the plurality of second magnetic body portions; and the third magnetic body portion is disposed on the one side of the first magnetic body portion with respect to the optical axis direction and in contact with the holding tube in the optical axis direction, The lens device according to claim 1, characterized in that, when viewed from the other side of the first magnetic material portion with respect to the optical axis direction, the portion of the retaining barrel overlaps with the plurality of second magnetic material portions so that the portion of the retaining barrel is positioned in front of the plurality of second magnetic material portions.

3. 3. The lens device according to claim 2, wherein the holding barrel has holes formed in an outer periphery thereof so that the plurality of second magnetic material portions can be seen.

4. 4. The lens device according to claim 3, wherein the hole has a size that allows the plurality of magnets and the plurality of second magnetic material portions to pass therethrough.

5. The lens device described in claim 3, characterized in that when the hole portion is viewed from outside the retaining barrel in a direction perpendicular to the optical axis direction, the portion of the retaining barrel overlaps with the fourth magnetic material portion so that the portion of the retaining barrel is positioned in front of the fourth magnetic material portion.

6. 3. The lens device according to claim 2, wherein the holding barrel has a plurality of first restricting portions that respectively restrict the positions of the plurality of second magnetic material portions in the optical axis direction.

7. 3. The lens device according to claim 2, wherein the holding barrel has a plurality of second restricting portions that respectively restrict the positions of the plurality of second magnetic portions in a direction perpendicular to the optical axis direction.

8. one end of the first magnetic body portion is held by the holding cylinder, the lens device further includes a holding member that holds the other end of the first magnetic body portion, The lens device according to claim 2, characterized in that a fixing portion that fixes the holding member to the holding tube overlaps with the second magnetic material portion so that the fixing portion is positioned in front of the second magnetic material portion when viewed from the other side of the first magnetic material portion in the optical axis direction.

9. 3. The lens device according to claim 2, wherein the plurality of second magnetic material portions are fixed to at least one of the holding tube, the third magnetic material portion, and the fourth magnetic material portion by adhesive.

10. 3. The lens device according to claim 2, wherein the third magnetic body portion is fixed to the holding tube by a fixing member from the side where the first magnetic body portion is disposed.

11. 3. The lens device according to claim 2, wherein the plurality of second magnetic body portions, the third magnetic body portion, and the fourth magnetic body portion are separate bodies.

12. The lens device described in claim 2, characterized in that when viewed along the optical axis direction, a straight line connecting the center of one of the plurality of magnets and the center of the first magnetic material portion intersects a first contact surface where one of the plurality of second magnetic material portions holding the one magnet contacts the third magnetic material portion, and a second contact surface where the one second magnetic material portion contacts the fourth magnetic material portion.

13. 3. The lens device according to claim 2, wherein the plurality of second magnetic body portions and the third magnetic body portion are integral with each other.

14. A holding cylinder; a moving member that holds a lens and is held by the holding barrel so as to be movable in the optical axis direction; a coil fixed to the moving member; a first magnetic portion disposed inside the coil and spaced apart from an inner circumferential portion of the coil; a plurality of magnets arranged facing an outer periphery of the coil and spaced apart from the outer periphery of the coil; a plurality of second magnetic portions that respectively hold the plurality of magnets; a third magnetic body portion disposed on one side of the first magnetic body portion in the optical axis direction and magnetically joining the first magnetic body portion and the plurality of second magnetic body portions; a fourth magnetic body portion that is disposed on the other side of the first magnetic body portion with respect to the optical axis direction and magnetically joins the first magnetic body portion and the plurality of second magnetic body portions; and The lens device is characterized in that the holding tube has holes formed in the outer periphery thereof so that the plurality of second magnetic material portions can be seen.

15. A holding cylinder; a moving member that holds a lens and is held by the holding barrel so as to be movable in the optical axis direction; a coil fixed to the moving member; a first magnetic portion disposed inside the coil and spaced apart from an inner circumferential portion of the coil; a plurality of magnets arranged facing an outer periphery of the coil and spaced apart from the outer periphery of the coil; a plurality of second magnetic portions that respectively hold the plurality of magnets; a third magnetic body portion disposed on one side of the first magnetic body portion in the optical axis direction and magnetically joining the first magnetic body portion and the plurality of second magnetic body portions; a fourth magnetic body portion that is disposed on the other side of the first magnetic body portion with respect to the optical axis direction and magnetically joins the first magnetic body portion and the plurality of second magnetic body portions; and The moving member is a first cover portion disposed on one side of the coil in the optical axis direction and covering one end of the coil; a second cover portion disposed on the other side of the coil in the optical axis direction and covering the other end of the coil; A lens device comprising:

16. the first cover portion has a first hole portion through which the first magnetic material portion passes, the second cover portion has a second hole portion through which the first magnetic material portion passes, 16. The lens device of claim 15, wherein a first inner diameter of the first hole and a second inner diameter of the second hole are smaller than an inner diameter of the coil.

17. A holding cylinder; a moving member that holds a lens and is held by the holding barrel so as to be movable in the optical axis direction; a coil fixed to the moving member; a magnet unit disposed inside the coil and spaced apart from an inner periphery of the coil; a plurality of first magnetic portions disposed opposite an outer periphery of the coil and spaced apart from the outer periphery of the coil; a second magnetic body portion that is disposed on one side of the magnet unit in the optical axis direction and magnetically joins the magnet unit and the plurality of first magnetic body portions; a third magnetic body portion that is disposed on the other side of the magnet unit in the optical axis direction and magnetically joins the magnet unit and the plurality of first magnetic body portions; and the second magnetic body portion is disposed on the one side of the magnet unit with respect to the optical axis direction and in contact with the holding tube in the optical axis direction, A lens device characterized in that, when viewed from the other side of the magnet unit in the optical axis direction, the portion of the retaining tube overlaps with the plurality of first magnetic material portions so that the portion of the retaining tube is positioned in front of the plurality of first magnetic material portions.

18. A holding cylinder; a moving member that holds a lens and is held by the holding barrel so as to be movable in the optical axis direction; a coil fixed to the moving member; a magnet unit disposed inside the coil and spaced apart from an inner periphery of the coil; a plurality of first magnetic portions arranged opposite to and spaced apart from the outer periphery of the coil; a second magnetic body portion that is disposed on one side of the magnet unit in the optical axis direction and magnetically joins the magnet unit and the plurality of first magnetic body portions; a third magnetic body portion that is disposed on the other side of the magnet unit in the optical axis direction and magnetically joins the magnet unit and the plurality of first magnetic body portions; and The lens device is characterized in that the holding tube has holes formed in the outer periphery thereof so that the plurality of first magnetic material portions can be seen.

19. A holding cylinder; a moving member that holds a lens and is held by the holding barrel so as to be movable in the optical axis direction; a coil fixed to the moving member; a magnet unit disposed inside the coil and spaced apart from an inner periphery of the coil; a plurality of first magnetic portions disposed opposite an outer periphery of the coil and spaced apart from the outer periphery of the coil; a second magnetic body portion that is disposed on one side of the magnet unit in the optical axis direction and magnetically joins the magnet unit and the plurality of first magnetic body portions; a third magnetic body portion that is disposed on the other side of the magnet unit in the optical axis direction and magnetically joins the magnet unit and the plurality of first magnetic body portions; and The moving member is a first cover portion disposed on one side of the coil in the optical axis direction and covering one end of the coil; a second cover portion disposed on the other side of the coil in the optical axis direction and covering the other end of the coil; A lens device comprising:

20. 20. The lens device according to claim 1, wherein the lens device is an interchangeable lens that is removably attached to a main body of an imaging device having an imaging element that captures an image formed by the lens device.

21. A lens device according to any one of claims 1 to 19; an imaging element that captures an image formed by the lens device; An imaging device comprising:

Images