Lens barrel and imaging device equipped therewith

Abstract

In a configuration employing an optical position detection unit to detect the position of the lens movement frame, the present invention provides a lens barrel that can prevent light leakage from the light-emitting part of the position detection unit from adversely affecting the image sensor on the camera body side, using a simple configuration. [Solution] The lens barrel 10 comprises a substantially cylindrical 4-group unit 21, a 5-group unit 23, a position detection unit 24, and a protruding portion 23c. The 5-group unit 23 is provided on the inner circumferential surface side of the 4-group unit 21 in a state that allows it to move in the optical axis direction of the lens L5. The position detection unit 24 has a light-emitting portion 24a, a reflector 24b, and a light-receiving portion 24c, and detects the position of the 5-group unit 23 relative to the 4-group unit 21 based on the change in the amount of light received by the light-receiving portion 24c. The protruding portion 23c is provided on the image plane side of the 5-group unit 23, opposite to the subject in the optical axis direction, and is provided to protrude radially outward from the light-emitting portion 24a.

Description

Technical Field

[0001] The present disclosure relates to a lens barrel that detects the position of a movable frame using an optical position detector, and an imaging device including the same.

Background Art

[0002] For example, Patent Document 1 discloses a zoom lens moving frame that holds a zoom lens inside, a lens barrel main body that holds the zoom lens moving frame together with the zoom lens in a state where it can move in the optical axis direction inside, and a position detector that detects the position of the zoom lens moving frame in the optical axis direction held inside the lens barrel main body. The position detector has an optical sensor and a detection object for the sensor. The detection object for the sensor is disclosed for a lens barrel including a sensor cut portion that is directly detected and a sensor cover that covers the optical sensor together with the sensor cut portion during position detection.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the above conventional lens barrel has the following problems. That is, in the lens barrel disclosed in the above publication, a sensor cover for preventing the intrusion of external light into the optical sensor is provided in order to prevent false detection during the position detection of the zoom lens moving frame. However, even if such a configuration can prevent false detection due to the intrusion of external light, in a configuration that employs an optical position detector to detect the position of the lens moving frame, the influence of light leakage from the light emitting portion of the optical position detector on the imaging element on the camera body side is not considered.

[0005] The object of this disclosure is to provide a lens barrel and an imaging device equipped therewith that can prevent, with a simple configuration, from light leakage from the light-emitting part of the position detection unit adversely affecting the image sensor on the camera body side, in a configuration that employs an optical position detection unit to detect the position of the lens movement frame. [Means for solving the problem]

[0006] The lens barrel according to this disclosure comprises a substantially cylindrical first outer frame, a lens movement frame, a position detection unit, and a protruding portion. The lens movement frame holds the lens and is provided on the inner circumferential surface side of the first outer frame so as to be movable in the optical axis direction of the lens. The position detection unit has a light-emitting portion that emits light, a reflecting portion provided at a position opposite the light-emitting portion that reflects the light emitted from the light-emitting portion, and a light-receiving portion that receives the light reflected by the reflecting portion, and detects the position of the lens movement frame relative to the first outer frame based on the change in the amount of light received by the light-receiving portion. The protruding portion is provided on the image plane side of the lens movement frame, opposite to the subject in the optical axis direction, and is provided so as to protrude radially outward from the light-emitting portion. [Effects of the Invention]

[0007] According to the lens barrel of this disclosure, in a configuration that employs an optical position detection unit to detect the position of the lens movement frame, it is possible to prevent light leakage from the light-emitting part of the position detection unit from adversely affecting the image sensor on the camera body side with a simple configuration. [Brief explanation of the drawing]

[0008] [Figure 1] An overall perspective view showing a lens barrel detachably attached to a camera body according to one embodiment of the present disclosure. [Figure 2] Figure 1 is a perspective view showing the configuration of the lens barrel. [Figure 3] Figure 1 is an exploded perspective view showing the configuration of the lens barrel. [Figure 4]Figure 1 is a front view of the lens barrel as seen from the subject side in the optical axis direction. [Figure 5] Figure 4 shows a cross-sectional view along the AF-AF line. [Figure 6] Figure 3 is a perspective view showing the configuration of the 3-group unit and the 4-5 group unit included in the lens barrel. [Figure 7] Figure 6 is an exploded perspective view showing the configuration of the 3-group unit and the 4-5 group unit. [Figure 8] Figure 7 is an exploded perspective view showing the configuration of the drive unit side of the 4-5 group unit. [Figure 9] Figure 7 is a perspective view showing the configuration of the 4th group unit included in the 4th-5th group unit. [Figure 10] Figure 7 is a perspective view showing the configuration of the 5th group unit included in the 4th-5th group unit. [Figure 11] Figure 10 is a front view of the 5-group unit as seen from the image plane side in the optical axis direction. [Figure 12] Figure 11 shows a cross-sectional view along line VV. [Figure 13] Figure 6 shows a front view of the 3-group unit and the 4-group unit, the 5-group unit, and the outer frame included in the 4-group and 5-group units, as seen from the image plane side in the optical axis direction. [Figure 14] Figure 6 shows a front view from the image plane side in the optical axis direction, with the 3-group unit and the 4-5 group unit combined. [Figure 15A] This is a cross-sectional view along the AA-AA line in the configuration shown in Figure 14, where the 5-group unit is at the limit position on the subject side. [Figure 15B] This is a cross-sectional view along the AA-AA line in the configuration shown in Figure 14, where the 5-group unit is at the limit position on the image plane side. [Figure 16] Enlarged view of section E in Figure 15A. [Figure 17A] Figure 7 is a side view showing the combined state of the 4-5 group units. [Figure 17B] Figure 17A shows a cross-sectional view along the WW line. [Figure 18] Enlarged view of section X in Figure 17B. [Modes for carrying out the invention]

[0009] Hereinafter, embodiments will be described in detail with reference to the drawings as appropriate. However, detailed descriptions that are more than necessary may be omitted. For example, detailed descriptions of well-known matters and redundant descriptions of substantially the same configurations may be omitted. This is to avoid making the following description unnecessarily redundant and to facilitate the understanding of those skilled in the art. Note that the applicant provides the accompanying drawings and the following description for those skilled in the art to fully understand the present disclosure, and does not intend to limit the subject matter described in the claims thereby.

[0010] (Embodiment 1) The lens barrel 10 according to an embodiment of the present disclosure and a camera (imaging device) 50 including the same will be described as follows with reference to FIGS. 1 to 18. (1) Configuration of the camera 50 As shown in FIG. 1, the camera (imaging device) 50 according to the present embodiment includes a lens barrel 10 and a camera body 51. The lens barrel 10 is detachably attached to the camera body 51. The detailed configuration of the lens barrel 10 will be described in detail later. The camera body 51 generates image data by imaging a subject image through the lens barrel 10 with an image sensor 52 (see FIG. 5) mounted therein.

[0011] (2) Overall configuration of the lens barrel 10 The lens barrel 10 according to the present embodiment is detachably attached to the camera body 51. As shown in FIGS. 2 and 3, the lens barrel 10 includes a first-group unit 11, a second-group unit 12, a third-group unit (third outer frame) 13, a fourth-fifth group unit 20, a sixth-group unit 14, a linear guide cylinder 15, a cam cylinder 17, and an exterior unit 16.

[0012] As shown in Figures 2 and 3, the first group unit 11 is a substantially cylindrical member that is positioned closest to the subject in the optical axis direction AX among the components that make up the lens barrel 10, and holds the lens (first lens group) L1 on its inner circumferential surface. The first group unit 11 has a cam follower (not shown) that moves while engaged with the cam groove 17a of the cam cylinder 17, which will be described later, and moves back and forth in the optical axis direction AX as the cam cylinder 17 rotates relative to the straight guide cylinder 15.

[0013] As shown in Figure 3, the second group unit (second lens frame) 12 holds the lens L2 and moves back and forth in the direction of the optical axis AX on the inner circumferential surface side of the straight guide cylinder 15 as the cam cylinder 17 rotates relative to the straight guide cylinder 15. The second group unit 12 has a substantially cylindrical main body portion 12a and a cam follower 12b that protrudes radially outward around the optical axis AX.

[0014] Three cam followers 12b are arranged on the outer circumferential surface of the substantially cylindrical main body portion 12a at approximately equal angles (about 120 degrees) apart. As the cam followers 12b move while engaged with the cam groove 17b of the cam cylinder 17 (described later), the relative rotation of the cam cylinder 17 with respect to the straight guide cylinder 15 causes the two-group unit 12 to move back and forth in the optical axis AX direction. As shown in Figure 3, the 3-group unit (third outer frame) 13 holds the lens L3 and has a substantially cylindrical main body portion 13a, a cam follower 13b, an aperture unit 13c, and a bag portion 13d (see Figure 13, etc.).

[0015] Three cam followers 13b are arranged on the outer circumferential surface of the substantially cylindrical main body portion 13a at approximately equal angles (about 120 degrees) apart. As the cam followers 13b move while engaged with the cam groove 17c of the cam cylinder 17 (described later), the 3-group unit 13 moves back and forth in the optical axis AX direction as the cam cylinder 17 rotates relative to the linear guide cylinder 15. The aperture unit 13c is located on the subject side in the optical axis AX direction of the main body 13a, and adjusts the amount of light incident from the subject side passing through the lens barrel 10 by opening and closing aperture blades (not shown) to change the aperture area.

[0016] The bag portion 13d is provided in a concave shape on the subject-facing surface in the optical axis AX direction of the main body portion 13a of the 3-group unit 13. The 4-5 group unit (first lens frame) 20 is a linear focus unit that adjusts the focal length by moving the lens L5, such as the internal focus lens, back and forth in the optical axis AX direction when the focus ring 16b, which is rotatably mounted on the outer surface of the outer unit 16, is rotated. As shown in Figure 3, the 4-5 group unit 20 holds the lenses L4 and L5 and has a substantially cylindrical main body 20a and a cam follower 20b.

[0017] Three cam followers 20b are arranged on the outer circumferential surface of the substantially cylindrical main body portion 20a at approximately equal angles (about 120 degrees) apart. The cam followers 20b move while engaged with the cam groove 17d of the cam cylinder 17, which will be described later. As a result of the relative rotation of the cam cylinder 17 with respect to the straight guide cylinder 15, the 4-5 group unit 20 moves back and forth in the optical axis AX direction. The detailed configuration of the 4-5 group unit 20 will be described in more detail later.

[0018] As shown in Figure 3, the 6-group unit 14 holds the lens L6 and moves back and forth in the direction of the optical axis AX on the inner circumferential surface side of the straight guide cylinder 15 as the cam cylinder 17 rotates relative to the straight guide cylinder 15. The 6-group unit 14 has a substantially cylindrical main body portion 14a and a cam follower 14b that protrudes radially outward from the optical axis AX. Three cam followers 14b are arranged on the outer circumferential surface of the substantially cylindrical main body portion 14a at approximately equal angles (about 120 degrees) apart. The cam followers 14b move while engaged with the cam groove 17e of the cam cylinder 17, which will be described later. As a result of the relative rotation of the cam cylinder 17 with respect to the straight guide cylinder 15, the 6-group unit 14 moves back and forth in the optical axis AX direction.

[0019] As shown in Figure 3, the straight guide tube 15 is a substantially cylindrical member positioned close to the inner circumferential surface of the cam cylinder 17, and the aforementioned 2nd group unit 12, 3rd group unit 13, 4th-5th group unit 20, and 6th group unit 14 are arranged on its inner circumferential surface. The straight guide tube 15 has a substantially cylindrical main body portion 15a and a straight groove 15b. The straight groove 15b is a through groove formed along the optical axis AX direction, and moves while engaged with the cam followers 12b, 13b, and 20b provided on the 2nd group unit 12, 3rd group unit 13, 4th-5th group unit 20, 6th group unit 14, etc.

[0020] The cam cylinder 17 is a substantially cylindrical member formed from, for example, aluminum, and as shown in Figure 3, is positioned on the outer circumferential surface side of the linear guide cylinder 15. By rotating relative to the linear guide cylinder 15, it drives the 2nd group unit 12, 3rd group unit 13, 4th-5th group unit 20, and 6th group unit 14 back and forth in the optical axis AX direction. As shown in Figure 3, the cam cylinder 17 has a substantially cylindrical main body portion 20a and a plurality of cam grooves 17a, 17b, 17c, 17d, 17e formed in the main body portion 20a.

[0021] Furthermore, the cam cylinder 17 is constructed by forming cam grooves 17a, 17b, 17c, 17d, and 17e on a substantially cylindrical aluminum member by machining. As shown in Figures 2 and 3, the exterior unit 16 is a substantially cylindrical member that constitutes the exterior portion of the lens barrel 10, and an annular zoom ring 16a, a focus ring 16b, etc., are attached to its outer surface in a manner that allows them to rotate along the circumferential direction.

[0022] As shown in Figures 2 and 3, the zoom ring 16a is a substantially annular member located near the approximate center of the exterior unit 16 in the optical axis direction AX. By rotating it, the lens barrel 10 moves from the WIDE position (see Figure 5) to the TELE position. As the zoom ring 16a rotates, the cam cylinder 17 rotates, causing the 1st group unit 11, 2nd group unit 12, 3rd group unit 13, 4th-5th group unit 20, and 6th group unit 14 to move back and forth in the optical axis direction AX.

[0023] As shown in Figures 2 and 3, the focus ring 16b is a substantially annular member provided on the outer circumferential surface of the outer unit 16 at a position adjacent to the subject side in the optical axis AX direction of the zoom ring 16a, and changes the position of the focus lens (lens L5) in the optical axis AX direction. As the focus ring 16b is rotated, the 4-5 group unit 20 moves back and forth in the optical axis AX direction.

[0024] (3) Configuration of the 4-5 group unit 20 In the lens barrel 10 according to this embodiment, as shown in Figures 4 and 5, the 4-5 group unit 20, which is arranged on the inner circumferential surface side of the straight guide cylinder 15 and cam cylinder 17 described above, is moved back and forth in the optical axis AX direction. At this time, the relative positions of the 4-group unit 21 and the 5-group unit 23 included in the 4-5 group unit 20 are detected using the optical position detection unit 24 shown in Figure 6.

[0025] As shown in Figure 6, the 4-5 group unit 20 is positioned on the image plane side of the 3 group unit 13, which is positioned on the subject side in the optical axis direction AX. As shown in Figure 7, the 4-5 group unit 20 comprises a 4 group unit 21, an outer frame 22, and a 5 group unit (lens movement frame) 23. The 4-group unit 21 includes a substantially cylindrical main body (first outer frame) 21a, a main shaft 21b, a sub-shaft 21c, a flexible hose 21d, a linear magnet 21ea, a linear yoke 21eb, a hole 21g (see Figure 9, etc.), and a light-shielding wall (first light-shielding wall) 21h (see Figure 17).

[0026] The main body (first outer frame) 21a has a roughly cylindrical shape and holds the lens L4 at its center. The main shaft 21b and the sub-shaft 21c are positioned in the main body 21a along the optical axis AX direction, and the guide hole 23d of the 5-group unit 23 is inserted into the main shaft 21b, and the guide hole 21e is inserted into the sub-shaft 21c.

[0027] As a result, the 5-group unit 23 is guided in the optical axis AX direction by the main axis 21b and the sub-axis 21c, and moves relative to the 4-group unit 21. The flexible circuit board 21d is connected to the position detection unit 24 and supplies power to the light-emitting unit 24a and the light-receiving unit 24c. The linear magnet 21ea is positioned opposite the linear coil 23f provided in the 5-group unit 23 shown in Figure 8 (see Figure 9).

[0028] As shown in Figure 8, the linear yoke 21eb is provided on the outer and inner surfaces of the substantially cylindrical main body 21a, and is positioned in contact with the inner and outer diameter surfaces of the linear magnet 21ea, respectively. The hole 21g is provided as a through-hole to release leaked light, in order to prevent light reflected from the bottom surface of the main body 21a of the 4-group unit 21 from reaching the image plane when the bottom surface is perpendicular to the optical axis AX direction. In particular, the hole 21g is designed to actively release leaked light so that it does not reach the image plane when the 5-group unit 23 is at its limit position on the image plane side (see Figure 15B).

[0029] Furthermore, when the 4-5 group unit 20 is assembled in a position adjacent to the 3 group unit 13, a bag portion 13d (see Figure 13) is provided at the position corresponding to the hole portion 21g in the 3 group unit 13. The pouch portion 13d is provided on the 3-group unit 13 to prevent light that has escaped towards the subject from being diffusely reflected inside the lens barrel 10 and reaching the image plane. The pouch portion 13d is provided to retain light inside.

[0030] The light-shielding wall (first light-shielding wall) 21h (see Figure 17) is an uneven wall surface that moves in close proximity to the reflector holding portion 23b of the movable 5-group unit 23. The structure for preventing light leakage using the light-shielding wall 21h will be described in detail later. As shown in Figure 9, the light-emitting section 24a and the light-receiving section 24c included in the position detection section 24 are positioned on the inner circumferential surface of the substantially cylindrical main body section 21a, at a position (hole section 21g) opposite to the reflector 24b of the movable 5-group unit 23.

[0031] Furthermore, as shown in Figure 10, the reflector 24b included in the position detection unit 24 is positioned such that the light emitted from the light-emitting unit 24a is reflected by the reflector 24b and received by the light-receiving unit 24c. The outer frame 22 is fixed relative to the main body portion 21a of the 4-group unit 21, and has a substantially disc-shaped main body portion (second outer frame) 22a, a recess 22b (see Figure 13), and an inclined surface 22c (see Figure 13).

[0032] As shown in Figures 7 and 8, the main body (second outer frame) 22a is a substantially disc-shaped member positioned closest to the image plane in the 4-5 group unit 20, and a recess 22b is provided at a position corresponding to the movable range of the reflector holding portion 23b of the movable 5 group unit 23. The recess 22b is provided in the main body 22a on a plane perpendicular to the optical axis AX, so as to be recessed toward the image plane. When the 4-group unit 21 moves to the position toward the image plane, the reflector 24b provided on the reflector holding portion 23b of the 5-group unit 23 is inserted into the recess 22b (see Figures 15A and 15B). The recess 22b has an inclined surface 22c at its concave bottom portion (see Figure 15A, etc.).

[0033] The inclined surface 22c is tilted obliquely outward in the radial direction with respect to a plane perpendicular to the optical axis AX (see Figure 15A, etc.). Further details regarding the light leakage countermeasures using the inclined surface 22c will be described later. As shown in Figure 10, the 5-group unit (lens moving frame) 23 holds the lens L5 and is provided on the inner circumferential surface side of the main body portion 21a of the 4-group unit 21 in a state that allows the lens L5 to move in the optical axis direction AX. The 5-group unit 23 has a main body portion 23a, a reflector holding portion (holding portion) 23b, a protruding portion 23c, guide holes 23d, 23e, a linear coil 23f, a linear flex 23g, and a light-shielding wall (second light-shielding wall) 23h.

[0034] As shown in Figure 8, the main body 23a is a substantially cylindrical member, and a reflector holder 23b for holding the reflector 24b, a linear coil 23f, and the like are arranged on its outer circumferential surface. As shown in Figure 10, the reflector holding part (holding part) 23b is provided such that the reflector 24b is positioned at a location where the light emitted from the light-emitting part 24a is reflected by the reflector 24b and received by the light-receiving part 24c.

[0035] As shown in Figures 11 and 12, the protruding portion 23c is located on the image plane side opposite to the subject in the optical axis AX direction in the 5-group unit 23, and is positioned to protrude radially outward from the light-emitting portion 24a (see Figure 18). As shown in Figure 12, the protruding portion 23c is located at the image plane side end of the reflector holding portion 23b in the optical axis AX direction. The protruding portion 23c is located on the image plane side in the optical axis AX direction, closer to the position where the light-emitting portion 24a, the light-receiving portion 24c, and the reflector 24b are arranged (see Figure 15A, etc.). The protruding portion 23c is positioned to cover the image plane side of the gap formed between the light-emitting portion 24a and the light-receiving portion 24c and the reflector 24b.

[0036] As shown in Figure 8, the linear coil 23f is positioned on the outer circumferential surface of the substantially cylindrical main body 23a, opposite the linear yoke 21eb. When current is supplied to the linear coil 23f, an electromagnetic force is generated between it and the linear yoke 21eb positioned opposite it, causing the 5-group unit 23 to move back and forth in the optical axis AX direction. The linear flex 23g is provided on the outer surface of the main body 23a and is connected to the linear coil 23f, supplying power to the linear coil 23f.

[0037] The light-shielding wall (second light-shielding wall) 23h is positioned in the 5-group unit 23 opposite the light-shielding wall 21h on the 4-group unit 21 side (see Figure 17). The structure for preventing light leakage using a 23h light-shielding wall will be described in detail later. As shown in Figures 9 and 10, the position detection unit 24 includes a light-emitting unit 24a that emits light, a reflector 24b positioned opposite the light-emitting unit 24a that reflects the light emitted from the light-emitting unit 24a, and a light-receiving unit 24c that receives the light reflected by the reflector (reflector) 24b. The position detection unit 24 detects the position of the 5-group unit 23 relative to the 4-group unit 21 based on the change in the amount of light received by the light-receiving unit 24c.

[0038] As shown in Figure 9, the light-emitting section 24a and the light-receiving section 24c are provided on the inner circumferential surface side of the substantially cylindrical main body 21a of the 4-group unit 21. The light-emitting unit 24a irradiates light onto the reflector 24b, which is positioned opposite it. As shown in Figure 7, the reflector (reflective part) 24b is held in a reflector holding part 23b provided on the outer circumferential surface of the substantially cylindrical main body part 23a of the 5-group unit 23. As shown in Figures 14 and 15A, the reflector 24b is provided in a position opposite to the light-emitting part 24a and the light-receiving part 24c in the 5-group unit 23. The reflector 24b has a reflective surface whose reflectivity changes in the direction of the optical axis AX, and the amount of reflected light changes when the position of the 5-group unit 23 in the direction of the optical axis AX changes.

[0039] Furthermore, as shown in Figure 15A, when the 5-group unit 23 moves toward the subject, the reflector 24b is inserted into the bag portion 13d provided on the 3-group unit 13 side. As a result, even if the light emitted from the light-emitting section 24a or the light reflected by the reflector 24b is diffusely reflected inside the lens barrel 10, the light is contained inside the bag portion 13d, effectively preventing it from reaching the image plane.

[0040] The light-receiving unit 24c, like the light-emitting unit 24a, is provided on the inner circumferential surface of the main body 21a of the 4-group unit 21, and receives light that is irradiated from the light-emitting unit 24a and reflected by the reflector 24b. In this embodiment, when the relative position of the 5-group unit 23 with respect to the 4-group unit 21 changes, the amount of light received by the light-receiving unit 24c changes, thereby allowing its position to be detected.

[0041] <Light leakage prevention measures using inclined surface 22c> In the lens barrel 10 of this embodiment, as shown in Figure 14, an inclined surface 22c is provided at the bottom of the recess 22b, which is formed to be inclined radially outward with respect to a line parallel to the optical axis AX on which the 4-group unit 21 moves. As a result, as shown in Figure 15A, when the 5-group unit 23 is moved to the closest position to the subject, the light leaking out from the gap between the light-emitting section 24a and the light-receiving section 24c and the reflector 24b approaches the image plane while being diffusely reflected within the recess 22b. At this time, since the bottom surface of the recess 22b is an inclined surface 22c that slopes radially outward, the light diffusely reflected within the recess 22b is directed radially outward, thus suppressing light leakage from the inner diameter gap towards the image plane.

[0042] On the other hand, as shown in Figure 15B, when the 5-group unit 23 is moved to the image plane side, the reflector holder 23b is inserted into the recess 22b. As a result, the light that is diffusely reflected in the gap between the light-emitting section 24a and the light-receiving section 24c and the reflector 24b remains in the recess 22b on the image plane side, thus suppressing light leakage toward the image plane side.

[0043] <Light leakage prevention structure using light-shielding walls 21h and 23h> In the lens barrel 10 of this embodiment, as shown in Figures 17A and 17B, a light leakage prevention structure is provided in the X portion where the light-emitting section 24a and light-receiving section 24c provided in the 4-group unit 21 and the reflector 24b provided in the 5-group unit 23 face each other. Specifically, the light-shielding wall 21h provided in the 4-group unit 21 is provided as part of a wall that forms a space for moving the reflector holding portion 23b in the main body portion 21a of the 4-group unit 21 in the optical axis AX direction. As shown in Figure 18, the light-shielding wall 21h is formed to protrude along the circumferential direction.

[0044] The light-shielding wall 23h provided in the 5-group unit 23 is located on the reflector holding portion 23b and is formed to protrude along the circumferential direction, as shown in Figure 18. Furthermore, the light-shielding walls 23h are provided on both sides of the reflector holder 23b so as to be inserted between the two light-shielding walls 21h on the 4-group unit 21 side. In this embodiment, the light-shielding wall 21h of the 4-group unit 21 and the light-shielding wall 23h of the 5-group unit 23 are arranged to overlap substantially in the radial direction (see the dashed line in Figure 18) in a cross-sectional view perpendicular to the optical axis AX with respect to the light-emitting section 24a, as shown in Figure 18. As a result, even if light is diffusely reflected in the gap between the light-emitting section 24a and the light-receiving section 24c and the reflector 24b, the light can be trapped in the labyrinthine gap formed between the light-shielding wall 21h of the 4-group unit 21 and the light-shielding wall 23h of the 5-group unit 23, thereby effectively suppressing light leakage toward the image plane.

[0045] <Key Features> As shown in Figure 7 and other figures, the lens barrel 10 of this embodiment comprises a substantially cylindrical 4-group unit 21, a 5-group unit 23, a position detection unit 24, and a protruding portion 23c. The 5-group unit 23 holds the lens L5 and is provided on the inner circumferential surface side of the 4-group unit 21 in a manner that allows movement in the optical axis AX direction of the lens L5. The position detection unit 24 has a light-emitting portion 24a that emits light, a reflector 4b provided at a position opposite the light-emitting portion 24a that reflects the light emitted from the light-emitting portion 24a, and a light-receiving portion 24c that receives the light reflected by the reflector 24b, and detects the position of the 5-group unit 23 relative to the 4-group unit 21 based on the change in the amount of light received by the light-receiving portion 24c. The protruding portion 23c is provided at a position on the image plane side opposite to the subject in the optical axis AX direction of the 5-group unit 23, and is provided to protrude radially outward from the light-emitting portion 24a.

[0046] As a result, in the lens barrel 10 which employs an optical position detection unit 24 to detect the position of the 5-group unit 23, the light leakage from the light-emitting part 24a of the position detection unit 24 that is directed toward the image sensor 52 is reduced by a protruding part 23c provided on the 5-group unit 23 side that protrudes radially outward from the light-emitting part 24a. As a result, the leakage of light emitted from the light-emitting part 24a of the position detection unit 24 adversely affects the image sensor 52 on the camera body 51, and this can be effectively suppressed with a simple configuration.

[0047] [Other embodiments] Although one embodiment of the present disclosure has been described above, the present disclosure is not limited to the above embodiment, and various modifications are possible without departing from the gist of the disclosure. (A) In the above embodiment, an example was given in which the 4-group unit 21 included in the 4-5 group unit 20 was used as the first outer frame of the present disclosure. However, the present disclosure is not limited thereto. For example, other frames may be used as the first outer frame of this disclosure.

[0048] (B) In the above embodiment, an example was given in which the 5-group unit 23 included in the 4-5 group unit 20 was used as the lens movement frame of the present disclosure. However, the present disclosure is not limited thereto. For example, other lens frames may be used as the lens movement frame in this disclosure.

[0049] (C) In the above embodiment, an example was given in which the projection 23c of the present disclosure is provided at the image plane-side end of the reflector holding portion 23b. However, the present disclosure is not limited thereto. For example, the protrusion of this disclosure may be provided not on the reflector holding portion (holding portion), but on another part of the 5-group unit 23, or on a part other than the 5-group unit.

[0050] (D) In the above embodiment, an example was described in which the light-emitting section 24a and the light-receiving section 24c are provided on the main body (first outer frame) 21a of the 4-group unit 21, and the reflector (reflecting section) 24b is provided on the 5-group unit (lens moving frame) 23. However, this disclosure is not limited thereto. For example, the light-emitting part and the light-receiving part may be provided on the lens movement frame, and the reflective part may be provided on the first outer frame.

[0051] (E) In the above embodiment, an example was given in which the configuration of the present disclosure is applied to a lens barrel 10 that is detachably attached to the camera body 51. However, the present invention is not limited thereto. For example, the configuration of this disclosure may be applied to a lens barrel that is fixed to the camera body in a non-detachable manner.

[0052] <Note> Based on the above description of embodiments, the following technologies are disclosed. (Technology 1) The lens barrel relating to Technology 1 is A roughly cylindrical first outer frame, A lens moving frame is provided on the inner circumferential surface side of the first outer frame so as to be movable in the optical axis direction of the lens, The system includes a light-emitting unit that emits light, a reflecting unit provided at a position opposite the light-emitting unit that reflects the light emitted from the light-emitting unit, and a light-receiving unit that receives the light reflected by the reflecting unit, and a position detection unit that detects the position of the lens moving frame relative to the first outer frame based on the change in the amount of light received by the light-receiving unit, A protruding portion is provided in the lens movement frame at a position on the image plane side opposite to the subject in the optical axis direction, and is provided to protrude radially outward from the light-emitting portion, It is equipped with.

[0053] (Technology 2) The lens barrel relating to Technology 2 is the lens barrel relating to Technology 1, The protruding portion is provided in the optical axis direction at a position closer to the image plane than the position where the light-emitting portion, the light-receiving portion, and the reflecting portion are arranged. (Technology 3) The lens barrel relating to Technology 3 is a lens barrel relating to Technology 1 or 2, The light-emitting unit and the light-receiving unit are provided on the first outer frame, The reflective portion is provided in the lens movement frame at a position opposite to the light-emitting portion and the light-receiving portion.

[0054] (Technology 4) The lens barrel relating to Technology 4 is a lens barrel relating to any one of Technology 1 to 3, The protruding portion is positioned to cover the image plane side of the gap formed between the light-emitting portion and the light-receiving portion and the reflecting portion. (Technology 5) The lens barrel relating to Technology 5 is the lens barrel relating to Technology 3, The lens moving frame has a holding portion for holding the reflecting portion, The aforementioned protrusion is provided at the end of the holding portion.

[0055] (Technology 6) The lens barrel relating to Technology 6 is a lens barrel relating to any one of Technology 1 to 5, The first outer frame has a first light-shielding wall provided near the light-emitting section, The lens moving frame has a second light-shielding wall positioned opposite the first light-shielding wall, In a cross-sectional view in a direction perpendicular to the optical axis with respect to the light-emitting portion, the first light-shielding wall and the second light-shielding wall are arranged to overlap in the radial direction.

[0056] (Technology 7) The lens barrel relating to Technology 7 is a lens barrel relating to any one of Technology 1 to 6, The lens moving frame is provided on the subject side in the optical axis direction, and further comprises a third outer frame having a substantially cylindrical main body and a bag portion provided on the subject side in the optical axis direction of the main body, The reflective portion provided on the lens movement frame is inserted into the bag portion when the lens movement frame moves to the position on the subject side.

[0057] (Technology 8) The lens barrel relating to Technology 8 is a lens barrel relating to any one of Technology 1 to 7, The first outer frame further has a hole that allows light to escape toward the subject. (Technology 9) The lens barrel relating to Technology 9 is a lens barrel relating to any one of Technology 1 to 8, The system further comprises a second outer frame having a recess provided so as to be recessed on the image plane side, and being fixed relative to the first outer frame, The reflective portion of the lens movement frame is inserted into the recess when the lens movement frame moves to the position on the image plane side.

[0058] (Technology 10) The lens barrel relating to technology 10 is the lens barrel relating to technology 9, The recess has a bottom surface, The bottom surface is inclined diagonally outward in the radial direction with respect to a plane perpendicular to the optical axis.

[0059] (Technology 11) The imaging device related to Technology 11 is A lens barrel relating to one of the technologies 1 through 10, The camera body to which the aforementioned lens barrel is attached, It is equipped with. [Industrial applicability]

[0060] The lens barrel of this disclosure employs an optical position detection unit to detect the position of the lens movement frame. This configuration has the advantage of preventing light leakage from the light-emitting part of the position detection unit from adversely affecting the image sensor on the camera body side with a simple configuration, and is therefore widely applicable to various lens barrels attached to imaging devices. [Explanation of symbols]

[0061] 10 Lens barrel 11 Group 1 Unit 12 Group 2 Units 12a Main body 12b Cam Follower 13. Group 3 Unit (Third Outer Frame) 13a Main body 13b Cam Follower 13c aperture unit 13d bag section 14 6-group unit 14a Main body 14b Cam Follower 15 Straight-ahead guide tube 15a Main body 15b Straight groove 16 Exterior Units 16a Zoom Ring 16b Focus Ring 17 Cam cylinder 17a~17e Cam groove 20 4-5 group units 20a Main body 20b Cam Follower 21 4-group unit 21a Main body (first outer frame) 21b Main shaft 21c subshaft 21d Flex 21ea Linear Magnet 21eb Linear Yoke 21g hole 21h Shading wall (1st shading wall) 22 Outer frame 22a Main body (second outer frame) 22b Recess 22c slope 23. 5-group unit (lens movement frame) 23a Main body 23b Reflector holding part (holding part) 23c Protrusion 23d guide hole 23e Guide hole 23f linear coil 23g Linear Flex 23h Light-shielding wall (second light-shielding wall) 24 Position detection unit 24a Light-emitting part 24b Reflector plate (reflector) 24c Light receiving part 50 Camera (imaging device) 51 Camera body AX optical axis C1 center axis L1~L6 Lenses

Claims

1. A roughly cylindrical first outer frame, A lens moving frame is provided on the inner circumferential surface side of the first outer frame so as to be movable in the optical axis direction of the lens, The device comprises a light-emitting unit that emits light, a reflective unit provided at a position opposite the light-emitting unit that reflects the light emitted from the light-emitting unit, and a light-receiving unit that receives the light reflected by the reflective unit, and a position detection unit that detects the position of the lens moving frame relative to the first outer frame based on the change in the amount of light received by the light-receiving unit, A protruding portion is provided in the lens movement frame at a position on the image plane side opposite to the subject in the optical axis direction, and is provided to protrude radially outward from the light-emitting portion, Equipped with, The light-emitting unit and the light-receiving unit are provided on the first outer frame, The reflective portion is provided in the lens moving frame at a position opposite to the light-emitting portion and the light-receiving portion. The aforementioned protruding portion protrudes toward the light-emitting portion and the light-receiving portion in the lens moving frame on which the reflecting portion is provided, so as to cover the image plane side of the gap formed between the light-emitting portion and the light-receiving portion and the reflecting portion. Lens barrel.

2. The aforementioned protrusion is provided in the optical axis direction at a position closer to the image plane than the position where the light-emitting portion, the light-receiving portion, and the reflecting portion are arranged. The lens barrel according to claim 1.

3. The lens moving frame has a holding portion for holding the reflecting portion, The aforementioned protrusion is provided at the end of the holding portion. The lens barrel according to claim 1.

4. A lens barrel according to claim 1 or 2, The camera body to which the aforementioned lens barrel is attached, An imaging device equipped with the following features.

Images