Lens barrel

The lens barrel includes a support frame and a retracting lens frame. The retracting lens frame is configured to support a lens and move around a retraction shaft with respect to the support frame during a transition period between an imaging enabled state and a housed state. The retraction shaft is substantially parallel to the optical axis. The retracting lens frame includes at least three contact portions. The at least three contact portions is configured to come into contact with the support frame at positions that are different from the retraction shaft. Movement of the retracting lens frame in the optical axis direction is restricted when the contact portions come into contact with the support frame. At least one of the contact portions is provided to the retracting lens frame so as to overlap the lens in a direction perpendicular to the optical axis.

BACKGROUND

1. Technical Field

The technology disclosed herein relates to a lens barrel equipped with an optical system.

2. Background Information

A lens barrel having three protrusions for positioning a subordinate optical system with respect to a main optical system has been disclosed in the past (see Japanese Laid-Open Patent Application S63-138320).

In prior art, the protrusions and the subordinate optical system are disposed at positions that are separated in the optical axis direction, so there is the risk that a unit constituted by a subordinate optical system holder and a member for supporting the subordinate optical system holder ends up being too large in the optical axis direction.

The technology disclosed herein was conceived in light of the above problem, and it is an object of the present technology to reduce the size (thickness) of a lens barrel in the optical axis direction.

SUMMARY

The lens barrel disclosed herein comprises a support frame and a retracting lens frame. The retracting lens frame is configured to support a lens and move around a retraction shaft with respect to the support frame during a transition period between an imaging enabled state and a housed state. The retraction shaft is substantially parallel to the optical axis. The retracting lens frame includes at least three contact portions. The at least three contact portions is configured to come into contact with the support frame at positions that are different from the retraction shaft. Movement of the retracting lens frame in the optical axis direction is restricted when the contact portions come into contact with the support frame. At least one of the contact portions is provided to the retracting lens frame so as to overlap the lens in a direction perpendicular to the optical axis.

The technology disclosed herein provides a lens barrel that can be made more compact.

DETAILED DESCRIPTION OF EMBODIMENTS

Selected embodiments of the present technology will now be explained with reference to the drawings. It will be apparent to those skilled in the art from this disclosure that the following descriptions of the embodiments of the present technology are provided for illustration only and not for the purpose of limiting the technology as defined by the appended claims and their equivalents.

Next, an embodiment of the present technology will now be described through reference to the drawings. In the description of the drawings that follows, portions that are the same or similar will be numbered the same or similarly. The drawings are merely schematic representations, however, and the proportions of the various dimensions and so forth may be different from those in actuality. Therefore, the specific dimensions and so forth should be determined by referring to the following description. Also, the mutual dimensional relations and proportions among the drawings may, of course, vary in some portions.

In the following embodiment, a digital camera will be described as an example of an imaging device. In the following description, assuming that the digital camera is in its landscape orientation, the subject side will be referred to as the “front,” the opposite side from the subject as the “rear,” the vertically upper side as “upper,” the vertically lower side as “lower,” the right side when facing the subject as “right,” and the left side when facing the subject as “left.” “Landscape orientation” is a kind of orientation of a digital camera, and when an image is captured in landscape orientation, the long-side direction of a rectangular image that is wider than it is tall substantially coincides with the horizontal direction within the image.

1. Overall Configuration of Digital Camera

The configuration of a digital camera1will be described through reference to the drawings.FIG. 1is an oblique view of the digital camera1.FIGS. 2 and 3are oblique views of a lens barrel20. InFIG. 2, the lens barrel20is shown in its retracted state, and inFIG. 3, the lens barrel20is shown in its wide angle state.

As shown inFIG. 1, the digital camera1comprises a housing10and the lens barrel20.

The housing10is made up of a front panel11, a rear panel12, and a side panel13. An opening10S is formed in the front panel11.

The lens barrel20comprises a three-stage telescoping zoom mechanism. The lens barrel20is housed in the housing10when not being used for imaging, and is deployed forward from the opening10S when used for imaging. More specifically, as shown inFIGS. 2 and 3, the lens barrel20has a first movable lens barrel part21, a second movable lens barrel part22, a third movable lens barrel part23, and a stationary lens barrel part24.

The first movable lens barrel part21is configured to deploy with respect to the stationary lens barrel part24. The second movable lens barrel part22is configured to deploy with respect to the first movable lens barrel part21. The third movable lens barrel part23is configured to deploy with respect to the second movable lens barrel part22. The stationary lens barrel part24is fixed inside the housing10. As shown inFIG. 3, when the lens barrel20is deployed, the third movable lens barrel part23is positioned the farthest forward out of the first to third movable lens barrel parts21to23.

2. Configuration of Lens Barrel

Next, the configuration of the lens barrel20will be described through reference to the drawings.FIG. 4is an exploded oblique view of the lens barrel20.

The first to third movable lens barrel parts21to23of the lens barrel20are deployed from the stationary lens barrel part24along the optical axis AX of the optical system. The optical system includes first to fifth lens groups L1 to L5. In the following description, a direction parallel to the optical axis AX will be called the “optical axis direction,” a direction perpendicular to the optical axis direction will be called the “radial direction,” and a direction that follows a circle whose center is the optical axis AX will be called the “peripheral direction.” The optical axis AX substantially coincides with the axis of the various frames that make up the lens barrel20.

As shown inFIG. 4, the lens barrel20comprises a stationary frame100, a master flange105, a first rectilinear frame110, a second rectilinear frame120, a third rectilinear frame130, a first rotary frame210, a second rotary frame220, a first cosmetic frame310, a second cosmetic frame320, a second lens group frame F2, a third lens group frame F3, a fourth lens group frame F4, and a fifth lens group frame F5.

In this embodiment, the stationary frame100and the master flange105constitute the stationary lens barrel part24. The first rectilinear frame110constitutes the third movable lens barrel part23. The third rectilinear frame130, the first rotary frame210, and the second cosmetic frame320constitute the second movable lens barrel part22. The second rectilinear frame120and the second rotary frame220constitute the first movable lens barrel part21.

The stationary frame100is in the form of a cylinder. The stationary frame100has a rectilinear groove a1 and a cam groove b1 formed in its inner peripheral face. A zoom motor101and a zoom gear102are attached to the outer peripheral face of the stationary frame100. The zoom motor101is a drive source for deploying the first to third movable lens barrel parts21to23. The zoom gear102transmits the drive force of the zoom motor101to the second rotary frame220.

The master flange105is a flat plastic member that covers the rear of the stationary frame100. An imaging element103is fitted in the center of a master flange244.

The first rectilinear frame110is in the form of a cylinder, and is disposed on the outside of the first rotary frame210. The first rectilinear frame110has a rectilinear groove a2 and a cam protrusion B2. The rectilinear groove a2 is formed along the optical axis direction on the inner peripheral face. The cam protrusion B2 is disposed at the rear end of the inner peripheral face. The cam protrusion B2 is engaged with a cam groove b2 of the first rotary frame210(discussed below). The first rectilinear frame110supports the first lens group L1 for bringing light into the lens barrel20. The first rectilinear frame110is covered by the first cosmetic frame310.

The second rectilinear frame120is in the form of a cylinder, and is disposed on the inside of the first rectilinear frame110. The second rectilinear frame120has a flange121, a rectilinear protrusion A1, a bayonet protrusion E1, a rectilinear protrusion A31, a rectilinear groove a32, and a cam groove b3. The flange121is formed in an annular shape, and is provided to the rear end part of the outer peripheral face. The rectilinear protrusion A1 is provided to the outer peripheral face of the flange121. The rectilinear protrusion A1 is engaged with the rectilinear groove a1 of the stationary frame100. The bayonet protrusion E1 is provided to the outer peripheral face of the flange121. The bayonet protrusion E1 is engaged with a bayonet groove e1 of the second rotary frame220(discussed below). The rectilinear protrusion A31 is formed on the outer peripheral face along the optical axis direction. The rectilinear protrusion A31 is engaged with the rectilinear groove a32 of the third rectilinear frame130(discussed below). The rectilinear groove a32 is formed in the outer peripheral face along the rectilinear protrusion A31. A rectilinear protrusion A32 of the third rectilinear frame130(discussed below) is engaged with the rectilinear groove a32. The cam groove b3 is formed in the outer peripheral face so as to intersect with the optical axis direction.

The third rectilinear frame130is in the form of a cylinder, and is disposed on the inside of the second rectilinear frame120. The third rectilinear frame130has a rectilinear protrusion A2, the rectilinear protrusion A32, a rectilinear groove a31, a bayonet protrusion E2, a through-groove c1, and a through-groove c2. The rectilinear protrusion A2 is provided to the front end part of the outer peripheral face. The rectilinear protrusion A2 is engaged with the rectilinear groove a2 of the first rectilinear frame110. The rectilinear protrusion A32 is formed in the outer peripheral face along the optical axis direction. The rectilinear protrusion A32 is engaged with the rectilinear groove a32 of the second rectilinear frame120. The rectilinear groove a31 is formed in the outer peripheral face along the rectilinear protrusion A32. The rectilinear protrusion A31 of the second rectilinear frame120is engaged with the rectilinear groove a31. The bayonet protrusion E2 is formed on the outer peripheral face along the peripheral direction. The bayonet protrusion E2 is engaged with a bayonet groove e2 of the first rotary frame210(discussed below). The through-groove c1 and the through-groove c2 pass through the frame main body from the inner peripheral face to the outer peripheral face, and are formed along the optical axis direction.

The first rotary frame210is in the form of a cylinder, and is disposed on the inside of the first rectilinear frame110. The first rotary frame210has a bayonet protrusion E3, a rectilinear protrusion A4, a cam protrusion B3, the cam groove b2, a cam groove b4, and a cam groove b5. The bayonet protrusion E3 is formed at the rear end part of the outer peripheral face, along the peripheral direction. The bayonet protrusion E3 is engaged with a bayonet groove e3 of the second cosmetic frame320(discussed below). The rectilinear protrusion A4 is provided to the outer peripheral face of the bayonet protrusion E3. The rectilinear protrusion A4 is engaged with a rectilinear groove a4 of the second rotary frame220(discussed below). The cam protrusion B3 is disposed on the inner peripheral face. The cam protrusion B3 is engaged with the cam groove b3 of the second rectilinear frame120. The cam groove b2 is formed in the outer peripheral face so as to intersect with the optical axis direction. The cam groove b4 and the cam groove b5 are formed in the inner peripheral face so as to intersect with the optical axis direction.

The second rotary frame220is in the form of a cylinder, and is disposed on the inside of the stationary frame100. The second rotary frame220has a gear part221, a cam protrusion B1, the rectilinear groove a4, and the bayonet groove e1. The gear part221is formed at the rear end part of the outer peripheral face, along the peripheral direction. When the gear part221meshes with a zoom gear242, the second rotary frame220is rotated in the peripheral direction by the drive force of the zoom motor101. The cam protrusion B1 is engaged with the cam groove b1 of the stationary frame100. The rectilinear groove a4 is formed in the inner peripheral face along the optical axis direction. The rectilinear protrusion A4 of the first rotary frame210is engaged with the rectilinear groove a4. The bayonet groove e1 is formed at the rear end part of the inner peripheral face, along the peripheral direction. The bayonet protrusion E1 of the first rectilinear frame110is engaged with the bayonet groove e1.

The first cosmetic frame310covers the front face and the outer periphery of the first rectilinear frame110. An opening is formed in the first cosmetic frame310for bringing light in from the outside. The first lens group L1 is disposed inside the opening in the first rectilinear frame110.

The second cosmetic frame320is in the form of a cylinder, and is disposed on the outside of the first rotary frame210. The second cosmetic frame320has a rectilinear protrusion A41 and the bayonet groove e3. The rectilinear protrusion A4 is provided to the rear end part of the outer peripheral face. The rectilinear protrusion A41 is engaged with the rectilinear groove a4 of the second rotary frame220. The bayonet groove e3 is formed at the rear end part of the inner peripheral face, along the peripheral direction. The bayonet protrusion E3 of the first rotary frame210is engaged with the bayonet groove e3.

The second lens group frame F2 is in the form of a disk, and is disposed on the inside of the third rectilinear frame130. The second lens group frame F2 supports a second lens group L2 used for zooming. The second lens group frame F2 has a cam protrusion B4 that is provided on the outer peripheral face. The cam protrusion B4 is inserted into the through-groove c1 of the third rectilinear frame130, and is engaged with the cam groove b4 of the first rotary frame210.

The third lens group frame F3 has a shutter unit and an OIS (optical image stabilizer) unit. The shutter unit supports the OIS unit. The shutter frame is in the form of a cylinder, and is disposed on the inside of the third rectilinear frame130. The third lens group frame F3 has a built-in shutter mechanism. The third lens group frame F3 has a cam protrusion B5 that is provided on the outer peripheral face. The cam protrusion B5 is inserted into the through-groove c2 of the third rectilinear frame130, and is engaged with the cam groove b5 of the first rotary frame210.

The OIS (optical image stabilizer) unit mainly has an OIS frame400and a retracting lens frame401.

The OIS frame400is mounted to a shutter frame335. The OIS frame400is movable within a plane that is perpendicular to the optical axis. For example, the OIS frame400is moved by an actuator within a plane that is perpendicular to the optical axis.

The retracting lens frame401is supported by the OIS frame400so as to be movable around a retraction shaft that is substantially parallel to the optical axis. The retracting lens frame401supports a third lens group L3 that is used for image blur correction. The third lens group L3 is made up of at least one lens. The position of the retracting lens frame401is changed from a correction enabled position (first orientation) in which the third lens group L3 executes image blur correction, to a retracted position (second orientation) in which the third lens group L3 is retracted from the optical axis.

The fourth lens group frame F4 is supported by the stationary frame100. The fourth lens group frame F4 supports a fourth lens group L4 that is used for focusing.

The fifth lens group frame F5 is supported by the master flange105. The fifth lens group frame F5 supports a fifth lens group L5.

3. Detailed Configuration of Members Constituting the Lens Barrel

A summary of the various members was given in “2. Configuration of Lens Barrel,” but here the configuration of the master flange105and the configuration of the third lens group frame F3 will be described in further detail.

As shown inFIG. 5, the master flange105has a master flange main body portion106(an example of a first main body portion), a master flange restrictor107(first restrictor), a first retracting cam125, and a second retracting cam126. The first main body portion106is in the form of a disk. The above-mentioned imaging element103is mounted in the center of the first main body portion106.

The first restrictor107restricts the movement of the OIS frame400. More precisely, the first restrictor107engages with the OIS unit251and restricts the movement of the OIS frame400. More specifically, the first restrictor107engages with the OIS unit251and restricts the movement of the OIS frame400when the lens barrel20transitions from its imaging enabled state to its retracted state (or, when the lens barrel20transitions from the retracted state to the imaging enabled state). The phrase “when the lens barrel20transitions from its imaging enabled state to its retracted state” here shall sometimes be used to include the meaning of “when the lens barrel20transitions from the retracted state to the imaging enabled state.”

As shown inFIGS. 5 and 6, the first restrictor107is formed integrally with the first main body portion106. The first restrictor107is constituted by two protrusions108that protrude outward from the first main body portion106. The two protrusions108engage with the OIS frame400of the OIS unit251. As shown inFIG. 6, the two protrusions108come into contact with the inner peripheral part120aof the second rectilinear frame120. This prevents the two protrusions108from falling over.

A sloped part is formed on the inner peripheral side of the distal ends of the protrusions108. These sloped parts guide the OIS frame400from a movable orientation in which the OIS frame400is movable (the orientation of the imaging enabled state), to a movement restricted orientation in which the movement of the OIS frame400is restricted.

The inner peripheral parts on the proximal end side of the protrusions (the portion excluding the above-mentioned distal end (sloped part) and including the middle part) are formed in a planar shape. The inner peripheral parts are the portions that support the OIS frame400in its movement restricted orientation. In-plane movement of the OIS frame400is reliably restricted by guiding the OIS frame400from the sloped parts on the distal end side to the inner peripheral part on the proximal end side. The way in which the in-plane movement of the OIS frame400is restricted will be described in detail in the description of the OIS frame400(engagement portion).

As shown inFIGS. 5 and 7, the first retracting cam125is a portion that is longer in one direction and formed integrally with the master flange105. The first retracting cam125has a first guide portion125a, a second guide portion125b, and a support portion125c.

The first guide portion125acomes into contact with a pressing portion605of the retracting lens frame401, and retracts the retracting lens frame401. The first guide portion125ais a portion that is formed inclined to the distal end of the first retracting cam125.

In a state in which the first guide portion125ais in contact with the pressing portion605, the OIS frame400is guided by the protrusions108from its movable orientation in which the OIS frame400is movable (the orientation of the imaging enabled state), to an orientation in which the movement of the OIS frame400is restricted (movement restricted orientation).

The second guide portion125bcomes into contact with the pressing portion605of the retracting lens frame401, and further retracts the retracting lens frame401. The second guide portion125bis formed continuously with the first guide portion125a, and is formed at a different angle from that of the first guide portion125a. In a state in which the second guide portion125bis in contact with the pressing portion605of the retracting lens frame401, the OIS frame400is in its movement restricted orientation.

The support portion125cis the portion that temporarily supports the retracting lens frame401in its retracted position. The retracting lens frame401is finally positioned by the second retracting cam126(discussed below). The support portion125cis formed straight in the optical axis direction. In a state in which the support portion125chas come into contact with the pressing portion605of the retracting lens frame401, the OIS frame400is in its movement restricted orientation.

The first retracting cam125is the portion that finally positions the retracting lens frame401. As shown inFIG. 5, the second retracting cam126is formed between the two protrusions108. The first retracting cam125has a sloped part. This sloped part guides the retracting lens frame401to the retracted position and positions it in the retracted position.

3-2. Third Lens Group Frame

3-2-1. Shutter Unit

As shown inFIG. 8, a shutter unit250is included in the third lens group frame F3. The shutter unit250(an example of a second frame body) is engaged with the third rectilinear frame130and the first rotary frame210as mentioned above. Also, the shutter unit250is supported by the master flange105(an example of a first frame body).

As shown inFIG. 9, the shutter unit250has a restrictor420(second restrictor) for restricting the movement of the OIS frame400, and a second stress dispersion portion422(the contact portion of the shutter unit) that comes into contact with a first stress dispersion portion511(the contact portion of the OIS frame) of the OIS frame400(discussed below). The second stress dispersion portion422is formed in an arc shape having a specific width. The details of the first stress dispersion portion511will be discussed below.

The shutter unit250further has a step portion423. The step portion423is formed on the face opposite the OIS frame400. When the retracting lens frame401has changed its orientation (position) from the first orientation to the second orientation (retracted orientation), a housing portion550of the retracting lens frame401(discussed below) is disposed at the step portion423. This affords a more compact size in the optical axis direction.

As shown inFIG. 8, the shutter unit250is included in the third lens group frame F3. The OIS unit251is disposed between the master flange105and the shutter unit250. The OIS unit251is mounted to the shutter unit250. The OIS unit251(an example of a first unit) has the OIS frame400(an example of a support frame), the retracting lens frame401, a thrust spring402(an example of a first biasing means), and a rotary spring403(an example of a second biasing means, and an example of a biasing member).

OIS Frame

The OIS frame400(an example of a support frame) is supported by the shutter unit250. The OIS frame400is configured to be movable within a plane that is perpendicular to the optical axis AX, with respect to the shutter unit250. The OIS frame400is moved by an actuator520in a plane that is perpendicular to the optical axis AX.

As shown inFIGS. 8 and 10to13, the OIS frame400has a main body portion500(second main body portion), a retraction shaft portion501, an anti-rotation portion502, at least three rail portions503, and engagement portions504(seeFIGS. 5 and 6).

As shown inFIG. 8, the second main body portion500is substantially in the form of a disk. The second main body portion500has the housing portion550for housing the retracting lens frame401. The housing portion550has two linking portions550athat are opposite to each other. The linking portions550aare formed integrally with the second main body portion500. More precisely, the linking portions550aare formed integrally with the second main body portion500so that the middle between the two linking portions550ais disposed in the approximate middle of the shutter unit250in the optical axis direction (the approximate middle in the thickness direction).

As shown inFIGS. 8 and 11, the retraction shaft portion501is formed on the second main body portion500. The retraction shaft portion501has a cylindrical part501aand a retraction shaft501b. The cylindrical part501ais formed on the outer peripheral part of the second main body portion500. The retraction shaft501bis formed on the second main body portion500. More specifically, the retraction shaft501bis formed on the second main body portion500so as to protrude toward the inside of the cylindrical part501a.

As shown inFIGS. 10 and 12, the anti-rotation portion502restricts the movement of the retraction shaft portion501produced by the rotary spring403. The anti-rotation portion502is formed protruding outward from the second main body portion500. The anti-rotation portion502has a sloped face502a. The sloped face502ais the portion that guides the retracting lens frame401toward the OIS frame400(the second main body portion500). The sloped face502ais sloped in a state of being opposite the second main body portion500. In other words, the sloped face502ais sloped with respect to the optical axis AX.

An example in which the sloped face502awas sloped at one angle was given here, but the sloped face502amay be formed so that it is sloped in multiple steps. Also, the sloped face502amay be formed so that it slopes in the form of a curved surface.

As shown inFIGS. 10 and 13, at least three rail portions503(503ato503c, for example) are formed on the second main body portion500. The rail portions503are formed on one face of the substantially disk-shaped second main body portion500. The rail portions503are formed on the second main body portion500at positions opposite contact portions603(a first contact portion603A and a second contact portion603B; discussed below) formed on the retracting lens frame401.

Also, as shown inFIG. 13, the rail portions503are formed on the second main body portion500in a portion that excludes a portion RM where the range over which the third lens group L3 supported by the retracting lens frame401moves is projected onto the second main body portion500, when the OIS frame400is viewed in the optical axis direction. Furthermore, the rail portions503are formed in a shape that corresponds to the path over when the contact portions603(the first contact portion603A and the second contact portion603B; discussed below) move when the lens barrel20changes from its imaging enabled state to its retracted state.

As discussed above, the engagement portions504engage with the first restrictor107formed on the master flange105, such as the two protrusions108(seeFIGS. 5 and 6). As shown inFIGS. 10 and 14, the engagement portions504are formed integrally with the second main body portion500. More specifically, the engagement portions504are portions that protrude outward from the outer peripheral part of the second main body portion500. These two engagement portion504respectively engage with the two protrusions108of the master flange105. More specifically, the engagement portions504are pressed by the protrusions108of the master flange105. This restricts the in-plane movement of the OIS frame400.

More precisely, as shown inFIG. 6, when the lens barrel20changes from its imaging enabled state to its retracted state, the OIS frame400moves in the optical axis direction with respect to the shutter unit250. The two protrusions108of the master flange105then respectively engage with the two protrusions of the OIS frame400, which restricts the in-plane movement of the OIS frame400. More precisely, first the engagement portions504respectively come into contact with the sloped faces formed on the inner peripheral side of the distal ends of the protrusions108, such as the inner peripheral side of the distal ends of the protrusions108. Next, the engagement portions504come into contact with the inner peripheral parts on the proximal end side of the protrusions108(the portion excluding the distal ends and including the middle). This guides the OIS frame400from the above-mentioned movable orientation to the movement restricted orientation, and restricts the in-plane movement of the OIS frame400in the movement restricted orientation.

In the overall configuration, when the lens barrel20changes from its imaging enabled state to its retracted state, the shutter unit250and the OIS unit251move in the optical axis direction with respect to the master flange105. This movement of the shutter unit250and the OIS unit251in the optical axis direction causes the master flange105to engage with the OIS frame400as discussed above, and restricts the in-plane movement of the OIS frame400.

As shown inFIG. 14, the OIS frame400further has a restricted portion510and the first stress dispersion portion511. The restricted portion510is the portion that receives the restrictor420of the shutter unit250. Here, when the restrictor420is disposed in the interior of the restricted portion510, the movement of the second main body portion500in the optical axis direction is restricted with respect to the shutter unit250. Meanwhile, the OIS frame400is movable within the plane that is perpendicular to the optical axis AX with respect to the shutter unit250.

The first stress dispersion portion511is the portion that comes into contact with the shutter unit250when the pressing portion605of the retracting lens frame401(discussed below) is pressed. The first stress dispersion portion511is provided to the OIS frame400at a position closer to the pressing portion605than the restricted portion510. The first stress dispersion portion511is formed in an arc shape having a specific width. Here, the width of the first stress dispersion portion511is less than the width of the second stress dispersion portion422. However, the second stress dispersion portion422may be formed so that its width becomes less than the width of the first stress dispersion portion511.

As shown inFIGS. 10 and 11, the OIS frame400further has an anti-detachment portion530(restrictor of the OIS frame400). The anti-detachment portion530is the portion that restricts detachment of the retracting lens frame401from the OIS frame400(the second main body portion500). The anti-detachment portion530is formed integrally with the retraction shaft portion501. The anti-detachment portion530is provided a specific distance away from the second main body portion500. The anti-detachment portion530is formed near the retraction shaft501b.

Retracting Lens Frame

The retracting lens frame401supports at least one lens. As shown inFIGS. 15A and 15B, the retracting lens frame401supports the third lens group L3, which is made up of four lenses. The retracting lens frame401is supported by the OIS frame400(seeFIG. 10). The retracting lens frame401moves around the retraction shaft501b, which is substantially parallel to the optical axis AX, when retracting. Consequently, the retracting lens frame401is disposed at a position that is shifted from the optical axis AX during retraction.

As shown inFIGS. 15A and 15B, the retracting lens frame401moves around the retraction shaft501b(axis JX) that is substantially parallel to the optical axis AX, when the lens barrel20changes from its imaging enabled state to its retracted state. More precisely, the position of the retracting lens frame401changes from a first orientation in which the third lens group L3 executes shake correction, to a second orientation in which the third lens group L3 is retracted from the optical axis AX, when the lens barrel20changes from its imaging enabled state to its retracted state.

As shown inFIGS. 16 and 17, the retracting lens frame401has a main body portion600(third main body portion600) of the retracting lens frame401, a shaft support601(an example of a bearing), a lens support602, and the plurality of contact portions603(603A to603C). The shaft support601is the portion that engages with the above-mentioned retraction shaft501b(seeFIG. 11). The shaft support601rotatably supports the retraction shaft501b. The shaft support601is a hole into which the retraction shaft501bis inserted, and this hole is formed in the third main body portion600.

As shown inFIG. 17, the shaft support601(hole) has at least two contact faces601athat come into contact with the retraction shaft501b. More precisely, the two contact faces601aare formed on the inner peripheral face of the shaft support601. The two contact faces601aare formed on the shaft support601on the proximal end side of the retraction shaft501b, that is, on the opening side of the shaft support601(hole) (seeFIG. 11). The two contact faces601aare formed on the inner peripheral face of the shaft support601so as to be in a mutually non-parallel relation. More specifically, when viewed in the depth direction, the shaft support601(hole) is formed in the inner peripheral face of the shaft support601so that the two contact faces601aare at an angle.

As shown inFIG. 17A, the two contact faces601a(hereinafter referred to as V-faces) come into contact with the outer peripheral face of the retraction shaft501b. More specifically, as shown inFIG. 17A, the retracting lens frame401is biased by the biasing force F0 of the rotary spring403, and the component force F1 of this biasing force F0 causes the V-faces601aformed on the shaft support601of the retracting lens frame401to come into contact with the outer peripheral face of the retraction shaft501b. This allows the retraction shaft501bto be positioned accurately with respect to the shaft support601of the retracting lens frame401. More precisely, precision with respect to the eccentricity of the retraction shaft501bcan be improved. InFIG. 17A, F1 and F2 are components of the biasing force F0.

The lens support602shown inFIG. 16is the portion that supports the third lens group L3 (four lenses). The lens support602is substantially in cylindrical in form, and supports the third lens group L3 on its inner peripheral part. In a state in which the retracting lens frame401has been mounted to the shutter unit250, the lens support602is disposed in the approximate middle of the shutter unit250in the optical axis direction (the approximate middle in the thickness direction).

The plurality of contact portions603shown inFIG. 16are, for example, made up of three first contact portions603A (603A1,603A2, and603A3), the second contact portion603B, and a third contact portion603C. The three first contact portions603A, the second contact portion603B, and the third contact portion603C are formed on the third main body portion600at different positions from the shaft support601. In other words, the three first contact portions603A, the second contact portion603B, and the third contact portion603C are formed on the third main body portion600at different positions from the retraction shaft501bsupported by the shaft support601. Also, the three first contact portions603A, the second contact portion603B, and the third contact portion603C are formed on the third main body portion600at different positions from the retraction shaft501bso as to allow contact with the OIS frame400.

More precisely, two of the contact portions603A1and603A2of the three first contact portions603A, and the second contact portion603B are formed on the third main body portion600near the retraction shaft501b. The two contact portions603A1and603A2are formed on the third main body portion600so that the retraction shaft501bis positioned between these two contact portions603A1and603A2.

The second contact portion603B is formed on the third main body portion600so that the retraction shaft501bis positioned between one of the two contact portions603A1and603A2and the second contact portion603B. Also, the other first contact portion603A3besides these two contact portions603A1and603A2, and the third contact portion603C are formed on the third main body portion600at positions that are away from the retraction shaft501b.

As shown inFIG. 16, a specific first contact portion603A (603A3) is formed on the third main body portion600so that the angle formed by a first line segment LN1 that connects the optical axis AX of the third lens group L3 supported by the lens support602to a specific first contact portion603A, and a second line segment LN2 that connects the optical axis AX of the third lens group L3 supported by the lens support602to the retraction shaft501bbecomes an obtuse angle. The “specific first contact portion603A” is at least one contact portion from among the three first contact portions603A. Here, the first contact portion603A3formed at the position farthest away from the retraction shaft501bcorresponds to the specific first contact portion.

In other words, the first contact portion formed at the position farthest away from the retraction shaft501bis formed on the third main body portion600so that a specific straight line LN3 is disposed between the retraction shaft501band the above-mentioned specific first contact portion603A. The specific straight line LN3 passes through the optical axis AX of the third lens group L3 supported by the lens support602, and is perpendicular to the second line segment LN2 that connects the retraction shaft501bto the optical axis AX of the third lens group L3 supported by the lens support602.

As shown inFIG. 18, at least one of the three first contact portions603A (603A1,603A2, and603A3), the second contact portion603B, and the third contact portion603C is formed on the third main body portion600so as to overlap the third lens group L3 in a direction perpendicular to the optical axis AX. In other words, at least one of the three first contact portions603A, the second contact portion603B, and the third contact portion603C is provided to the retracting lens frame401so as to overlap the third lens group L3 within a range D of the thickness of the third lens group L3. Here, the three first contact portions603A, the second contact portion603B, and the third contact portion603C are provided to the retracting lens frame401so as to overlap the third lens group L3 in a direction perpendicular to the optical axis AX within the range D of the thickness of the third lens group L3.

Here, at least three of the three first contact portions603A (603A1,603A2, and603A3), the second contact portion603B, and the third contact portion603C is configured to come into contact with the OIS frame400. Specifically, if at least three contact portions out of the three first contact portions603A and the second contact portion603B come into contact with the OIS frame400, this restricts the movement of the retracting lens frame401in the optical axis direction.

More precisely, if at least three contact portions out of the three first contact portions603A and the second contact portion603B come into contact with the rail portions503of the OIS frame400(seeFIG. 14), this restricts the movement of the retracting lens frame401in the optical axis direction. More specifically, when the lens barrel20is in its imaging enabled state, the three first contact portions603A1,603A2, and603A3respectively come into contact with the rail portions503a,503b, and503cof the OIS frame400. Here, the first contact portion603A1comes into contact with the rail portion503a, the first contact portion603A2comes into contact with the rail portion503b, and the first contact portion603A3comes into contact with the rail portion503c. In this case, the second contact portion603B does not come into contact with the rail portions503.

On the other hand, when the lens barrel20is in its retracted state, the two first contact portions603A2and603A3and the second contact portion603B respectively come into contact with the rail portions503a,503b, and503cof the OIS frame400. Here, when the lens barrel20has changed from the imaging enabled state to the retracted state, one of the three first contact portions603A, such as the first contact portion603A1, separates from the rail portion503, and the second contact portion603B comes into contact with that rail portion503. Thus having at least three contact portions out of the three first contact portions603A and the second contact portion603B come into contact with the rail portions503of the OIS frame400reliably restricts the movement of the retracting lens frame401in the optical axis direction.

The third contact portion603C comes into contact with the OIS frame400when the lens barrel20changes from the imaging enabled state to the retracted state. This will be discussed in detail below.

As shown inFIG. 16, the retracting lens frame401further has the pressing portion605and an engagement portion606. The pressing portion605is the portion that is pressed when the retracting lens frame401changes from the imaging enabled state to the retracted state. More precisely, when the retracting lens frame401changes from the imaging enabled state to the retracted state, the pressing portion605is pressed by the first retracting cam125and the second retracting cam126provided to the master flange (seeFIG. 5). When the pressing portion605is thus pressed, the load exerted on the restrictor420and the restricted portion510is limited by allowing the first stress dispersion portion511(FIG. 14) and the second stress dispersion portion422(seeFIG. 9) to come into contact with each other.

The engagement portion606is the portion that engages with the anti-detachment portion530. At the retracting lens frame401, if the engagement portion606is disposed between the second main body portion500(the main body portion of the OIS frame400) and the anti-detachment portion530(seeFIG. 11), detachment of the retracting lens frame401in the optical axis direction is restricted. As shown inFIG. 16, the engagement portion606is formed integrally with the shaft support601. The engagement portion606is formed in an arc shape. A cut-out606cis formed in the engagement portion606. The engagement portion606is disposed between the anti-detachment portion530and the third main body portion600by introducing the anti-detachment portion530into the cut-out606c.

Thrust Spring

The thrust spring402is a spring that biases the retracting lens frame401with respect to the OIS frame400. As shown inFIGS. 8 and 11, the thrust spring402is mounted to the OIS frame400and/or the retracting lens frame401.

The thrust spring402has a pair of opposing parts440and a linking portion441that links the two opposing parts440. One of the two opposing parts440(the first opposing part440a) is mounted to the OIS frame400, and the other opposing part440(the second opposing part440b) is mounted to the retracting lens frame401. More precisely, as shown inFIG. 11, in a state in which the retraction shaft501bof the OIS frame400is supported by the shaft support601of the retracting lens frame401, the first opposing part440ais mounted to the OIS frame400, and the second opposing part440bis mounted to the retracting lens frame401. Consequently, the thrust spring402clamps the OIS frame400and the retracting lens frame401.

Consequently, the thrust spring402brings at least two of the contact portions603into contact with the OIS frame400. Here, the thrust spring402brings at least two of the contact portions out of the two first contact portions603A (603A1and603A2) and the second contact portion603B formed near the retraction shaft501b(the shaft support601) into contact with the OIS frame400.

Rotary Spring

The rotary spring403is a spring that biases the retracting lens frame401around the retraction shaft501b. The rotary spring403shown inFIG. 8is supported by the OIS frame400. The rotary spring403is a torsion coil spring, for example. As shown inFIGS. 11 and 17B, a portion403cof the coil of the rotary spring403(the coil part) is mounted around the outside of the cylindrical part501aof the retraction shaft portion501. One end403aof the rotary spring403is mounted in a groove444formed in the OIS frame400. The other end403bof the rotary spring403is mounted in a groove445formed in the retracting lens frame401.

When the rotary spring403biases the retracting lens frame401, the third contact portion603C of the retracting lens frame401comes into contact with the sloped face502aof the OIS frame400. The third contact portion603C is then guided by the sloped face502a, and the retracting lens frame401approaches the OIS frame400. This positions the retracting lens frame401with respect to the OIS frame400. In this state, the first contact portion603A3is in contact with the OIS frame400.

As shown inFIG. 17b, in this embodiment, when the rotary spring403is viewed in the center axis direction of the coil part403c, the other end403B of the rotary spring403is in the form of a straight line. Instead, as shown inFIG. 17C, the distal end403b2of the other end403B of the rotary spring403may be bent with respect to the proximal end403b1(the portion near the coil part403c).

More specifically, using the proximal end403b1of the rotary spring403as a reference, the distal end403b2of the rotary spring403is bent. In other words, using the proximal end403b1as a reference, the distal end403b2is bent in the rotation direction of the retracting lens frame401. Even more specifically, using the proximal end403b1as a reference, the distal end403b2is bent so as to move closer to the coil part403c.

In this case, a spring receiver607is formed on the retracting lens frame401, and the distal end403b2of the other end403B of the rotary spring403comes into contact with this spring receiver607.

As a result of this configuration, as shown inFIG. 17C, the component force F1′ of the biasing force F0′ of the rotary spring403causes the V-faces601aformed in the shaft support601of the retracting lens frame401to come into contact with the outer peripheral face of the retraction shaft501b. InFIG. 17C, the component force F1′ at which the V-faces601aof the retracting lens frame401are brought into contact with the outer peripheral face of the retraction shaft501bis greater than that inFIG. 17B(F1′>F1). Consequently, the retraction shaft501bis positioned more reliably with respect to the shaft support601of the retracting lens frame401. More precisely, accuracy with respect to the eccentricity of the retraction shaft501bcan be improved more reliably. InFIG. 17C, F1′ and F2′ are components of the biasing force F0′.

The amount and direction of the component force F1′ by which the V-faces601aare biased toward the retraction shaft vary with the position where the V-faces are formed. Specifically, the bending of the rotary spring403and the formation position of the V-faces601ainFIG. 17Bare just examples given to illustrate this technology. Therefore, the bending of the rotary spring403is not limited to how it is done in this embodiment, and any way is fine as long as the component force F1′ by which the V-face are biased toward the retraction shaft can be increased.

The actuator520is mounted to the third lens group frame F3. More precisely, as shown inFIG. 19, the actuator520is disposed on the third lens group frame F3, using an effective imaging range YR as a reference. The effective imaging range YR is defined by the imaging element103mounted to the master flange105. In this embodiment, the effective imaging range YR is formed in a rectangular shape.

As shown inFIG. 19, the actuator520has a first actuator521and a second actuator522. The first actuator521moves the OIS frame400in a short-side direction T1 (first direction) of the effective imaging range YR. The first actuator521is disposed on one short side of the effective imaging range YR. The first actuator521is made up of a magnet521aand a coil521b. The magnet521ais mounted to the OIS frame400, and the coil521bis mounted to the shutter unit250at a position opposite the magnet521a.

As shown inFIG. 19, the second actuator522moves the OIS frame400in a long-side direction T2 (second direction) of the effective imaging range YR. The second actuator522is larger than the first actuator521. The second actuator522is disposed on one long side of the effective imaging range YR. More specifically, the second actuator522is disposed on the lower long side of the effective imaging range YR. The second actuator522is made up of a magnet522aand two coils522b. The magnet522ais mounted to the OIS frame400, and the two coils522bare mounted to the shutter unit250at a position opposite the magnet522a. The retracting lens frame401moves along the other long side of the effective imaging range YR (such as the upper long side).

In this state, when power is supplied from a camera circuit (not shown) to the coils521band522bof the shutter unit250, current flows and a magnetic field is generated in the coils521band522b. This magnetic field drives the magnets521aand522aof the OIS frame400, and this drive force causes the OIS frame400to move in a plane that is perpendicular to the optical axis AX. More precisely, the OIS frame400is moved by the first actuator521in the short-side direction, and is moved by the second actuator522in the long-side direction.

4. Engagement of Frames

FIGS. 5 to 7are cross sections of the lens barrel20. However,FIGS. 5 to 7are simplified diagrams that combine a plurality of cross sections passing through the optical axis AX. InFIG. 5the lens barrel20is shown in its retracted state, inFIG. 6the lens barrel20is shown in its wide angle state, and inFIG. 7the lens barrel20is shown in its telephoto state.

As shown inFIG. 5, in the retracted state, the second rotary frame220, the second cosmetic frame320, the first cosmetic frame310, the first rectilinear frame110, the first rotary frame210, the second rectilinear frame120, and the third rectilinear frame130are housed in that order on the inside in the radial direction of the stationary frame100. Also, in the retracted state, the third lens group L3 retracts outward in the radial direction of the fourth and fifth lens groups L4 and L5, which allows the lens barrel20to be more compact in the optical axis direction.

The engagement of the frames will now be described through reference toFIGS. 6 and 7.

The gear part221of the second rotary frame220meshes with the zoom gear102(not shown). The cam protrusion B1 of the second rotary frame220is engaged with the cam groove b1 of the stationary frame100. Consequently, the second rotary frame220moves in the optical axis direction while rotating in the peripheral direction under the drive force of the zoom motor101.

The rectilinear protrusion A1 of the second rectilinear frame120is engaged with the rectilinear groove a1 of the stationary frame100. The bayonet protrusion E1 of the second rectilinear frame120is engaged with the bayonet groove e1 of the second rotary frame220. Therefore, the second rectilinear frame120moves in the optical axis direction along with the second rotary frame220.

The rectilinear protrusion A4 of the first rotary frame210is engaged with the rectilinear groove a4 of the first rotary frame210. The cam protrusion B3 of the first rotary frame210is engaged with the cam groove b3 of the second rectilinear frame120. Therefore, the first rotary frame210moves in the optical axis direction along with the second rectilinear frame120while rotating in the peripheral direction along with the first rotary frame210.

The cam protrusion B2 of the first rectilinear frame110is engaged with the cam groove b2 of the first rotary frame210. The rectilinear protrusion A2 of the third rectilinear frame130is engaged with the rectilinear groove a2 of the first rectilinear frame110. Therefore, the first rectilinear frame110moves in the optical axis direction according to the rotation of the first rotary frame210.

The bayonet protrusion E2 of the third rectilinear frame130is engaged with the bayonet groove e2 of the second rotary frame220. The rectilinear protrusion A2 of the third rectilinear frame130is engaged with the rectilinear groove a2 of the first rectilinear frame110. Therefore, the third rectilinear frame130moves in the optical axis direction along with the first rotary frame210.

As discussed above, the first rotary frame210is engaged with the first rectilinear frame110via a cam mechanism, and rotates to move the first rectilinear frame110rectilinearly. Also, the second rectilinear frame120is engaged with the first rotary frame210via a cam mechanism, and moves rectilinearly in the optical axis direction to rotate the first rotary frame210. Accordingly, the first rotary frame210is moved by moving the second rectilinear frame120rectilinearly while moving the first rectilinear frame110rectilinearly by rotating the first rotary frame210, by rotating the second rotary frame220with the zoom motor101. As a result, the first to third movable lens barrel parts21to23are deployed smoothly from the stationary lens barrel part24.

5. Operation of OIS Unit

Finally, the operation of the OIS unit will be described on the basis of the configuration of the lens barrel20discussed above.

First, as shown inFIG. 15A, in the imaging enabled state, the third contact portion603C of the retracting lens frame401comes into contact with the anti-rotation portion502, which positions the retracting lens frame401with respect to the OIS frame400in the first orientation (imaging enabled orientation).

Next, when the lens barrel20starts changing from its imaging enabled state to its retracted state, the shutter unit250approaches the master flange105as shown inFIG. 6. The engagement portions504of the OIS frame400mounted to the shutter unit250then come into contact with the distal ends of the protrusions108provided to the master flange105. The distal ends of the protrusions108then press on the OIS frame400. Once the engagement portions504of the OIS frame400come into contact with the inner peripheral part of the protrusions108(the portion more to the proximal end side than the distal end), movement of the OIS frame400with respect to the shutter unit250is restricted.

Meanwhile, in a state in which the OIS frame400is being pressed by the protrusions108of the master flange105, the pressing portion605of the retracting lens frame401is pressed and guided by the first retracting cam125provided to the master flange105.

More precisely, in a state in which the OIS frame400is being pressed by the distal ends of the protrusions108, the pressing portion605of the retracting lens frame401comes into contact with and is guided by the first guide portion125aof the first retracting cam125(seeFIG. 7), causing the retracting lens frame401to start retracting from the first orientation toward the second orientation (retracted orientation).

Then, in a state in which the OIS frame400is being pressed by the inner peripheral part on the proximal end side of the protrusions108(the portion excluding the distal ends and including the middle), the pressing portion605of the retracting lens frame401comes into contact with and is guided by the second guide portion125bof the first retracting cam125(seeFIG. 7), causing the retracting lens frame401to retract further. The pressing portion605of the retracting lens frame401then comes into contact with the support portion125cof the first retracting cam125(seeFIG. 7).

Finally, when the shutter unit250further approaches the master flange105, a positioning portion609provided to the retracting lens frame401comes into contact with the second retracting cam126. This positions the retracting lens frame401in the retracted position.

Here, the direction in which the protrusions108of the master flange105press on the engagement portions504of the OIS frame400is substantially the same as the direction in which the first retracting cam125of the master flange105presses on the pressing portion605of the retracting lens frame401. In other words, the protrusions108of the master flange105and the first retracting cam125of the master flange105press on the engagement portions504of the OIS frame400and the first retracting cam125of the retracting lens frame401in the direction in which the OIS frame400approaches the shutter unit250. Thus pressing the engagement portions504of the OIS frame400and the first retracting cam125of the retracting lens frame401in substantially the same direction allows the retracting lens frame401to be positioned reliably.

Thus, the movement of the OIS frame400with respect to the shutter unit250is restricted, and the retracting lens frame401is positioned with respect to the OIS frame400in the second orientation (retracted orientation). At this point, the lens support602of the retracting lens frame401is housed in the housing portion550of the OIS frame400.

Thus, with this lens barrel20, when the lens barrel20changes from its imaging enabled state to its retracted state, the restriction of movement of the OIS frame400and the positioning of the retracting lens frame401are executed simultaneously. Specifically, the lens barrel20of this embodiment retracts the third lens group L3 used for OIS. Here again, movement of the OIS frame400itself is restricted with a restricting mechanism that restricts the movement of the OIS frame400(e.g., the relation between the inner peripheral part of the protrusions108and the engagement portions504of the OIS frame400), before the third lens group L3 is retracted with a retracting mechanism (e.g., the relation between the pressing portion605of the retracting lens frame401and the first retracting cam125provided to the master flange105). This allows the third lens group L3 to be retracted more reliably.

6. Action and Effect

(1-1) This lens barrel20comprises the OIS frame400and a retracting lens frame401. The retracting lens frame401supports a third lens group L3. The retracting lens frame401moves around a retraction shaft501bsubstantially parallel to the optical axis, with respect to the OIS frame400during a transition period between the imaging enabled state and the housed state. The retracting lens frame401has at least three contact portions603. The three or more contact portions603come into contact with the OIS frame400at positions that are different from the retraction shaft501b. When the contact portions603come into contact with the OIS frame400, movement of the retracting lens frame401in the optical axis direction is restricted. At least one of the contact portions603is provided to the retracting lens frame401so as to overlap the lens L3 in a direction perpendicular to the optical axis.

With this lens barrel20, at least one of the contact portions603(603A to603C) and the third lens group L3 (retracting lens) are disposed so as to overlap each other in a direction perpendicular to the optical axis AX. This allows the OIS unit made up of the OIS frame400and the retracting lens frame401to be smaller in the optical axis direction. Specifically, the lens barrel20can be made smaller (thinner) in the optical axis direction.

Also, with this lens barrel20, at least one of the contact portions603(603A to603C) and the third lens group L3 (retracting lens) are disposed so as to overlap each other in a direction perpendicular to the optical axis AX. That is, the contact face of the contact portion603is disposed at a position near the center of gravity of the retracting lens frame401in a direction perpendicular to the optical axis. Consequently, when the retracting lens frame401moves around the retraction shaft, it can move in a state in which the accuracy of the third lens group L3 in the optical axis is maintained.

(1-2) This lens barrel20comprises a thrust spring402. The thrust spring402is fixed to the OIS frame400, and biases the retracting lens frame401with respect to the OIS frame400. The thrust spring402brings at least two of the contact portions603into contact with the OIS frame400.

With this lens barrel20, because the thrust spring402biases the retracting lens frame401with respect to the OIS frame400, two or more of the contact portions603(603A to603C) can be brought into contact with the retracting lens frame401. This reliably ensures good vertical accuracy (inclination accuracy, tilt accuracy, etc.) of the retracting lens frame401(the retracting lens L3).

(1-3) This lens barrel20further comprises a rotary spring403. The rotary spring403is fixed to the OIS frame400, and biases the retracting lens frame401around the retraction shaft501b. The OIS frame400has an anti-rotation portion502. The anti-rotation portion502restricts movement of the retracting lens frame401by the rotary spring403. The anti-rotation portion502has a sloped face502athat is sloped with respect to the optical axis. When the retracting lens frame401is biased by the rotary spring403, one of the three or more contact portions603comes into contact with the sloped face502a, and this guides the retracting lens frame401toward the OIS frame400.

With this lens barrel20, when the retracting lens frame401is biased by the rotary spring403, one of the contact portions603(603C) hits the sloped face502aof the anti-rotation portion502, and the retracting lens frame401is guided toward the OIS frame400. This presses the retracting lens frame401toward the OIS frame400. Specifically, the contact portions603of the retracting lens frame401reliably come into contact with the OIS frame400.

(1-4) With this lens barrel20, at least one of the contact portions603is provided to the retracting lens frame401so as to overlap the third lens group L3 in a direction perpendicular to the optical axis Ax within the thickness range of the lens group L3.

With this lens barrel20, at least one of the contact portions603(603A to603C) overlaps the lens in a direction perpendicular to the optical axis AX within the thickness range of the third lens group L3. Consequently, the OIS unit made up of the OIS frame400and the retracting lens frame401can be smaller in the optical axis direction. Specifically, the lens barrel20can be made smaller (thinner) in the optical axis direction.

(1-5) With this lens barrel20, at least three of four contact portions603can come into contact with the OIS frame400.

With this lens barrel20, three of the four contact portions603(603A to603D) are configured to come into contact with the retracting lens frame401. For example, in the imaging enabled state, three contact portions603A1,603A2, and603A3are configured to come into contact with corresponding rail portions503. In the retracted state, the three contact portions603B,603A2, and603A3are configured to come into contact with corresponding rail portions503. Specifically, with this lens barrel20, the contact portions (603A to603C) that come into contact with the rail portions503can be changed according to the state. This allows three-point support at all times, even if the shape of the retracting lens frame401and/or the shape of the OIS frame400is complex.

(1-6) With this lens barrel20, two contact portions603are in contact with the OIS frame400on both sides of a straight line LN2 linking the retraction shaft501band the third lens group L3, so the tilt accuracy of the retracting lens frame401can be improved.

(2) In prior art, the protrusions on the subsidiary optical system holder (corresponds to the retracting lens frame) formed near the subsidiary optical system are perpendicular to a straight line linking the retraction shaft and the optical axis, and are formed on a straight line that passes through the optical axis (seeFIG. 6). This makes it difficult to ensure good vertical accuracy of the subsidiary optical system holder.

The technology disclosed herein was conceived in light of the above problem, and it is an object of the present technology to reliably ensure good vertical accuracy of the retracting lens frame.

The lens barrel disclosed herein comprises a support frame and a retracting lens frame. The retracting lens frame supports a lens and moves around a retraction shaft substantially parallel to the optical axis, with respect to the support frame during a transition period between an imaging enabled state and a housed state. The retracting lens frame has at least three contact portions. The three or more contact portions come into contact with the support frame at positions that are different from the retraction shaft. When the contact portions come into contact with the support frame, movement of the retracting lens frame in the optical axis direction is restricted. At least one of the contact portions is provided to the retracting lens frame so that the angle formed by a line segment linking the one or more contact portions and the optical axis of the lens and a line segment linking the retraction shaft and the optical axis of the lens is an obtuse angle.

The technology disclosed herein provides a lens barrel with which good vertical accuracy of the retracting lens frame can be reliably ensured.

The configuration and effect discussed above will now be described in specific terms.

(2-1) This lens barrel20comprises the OIS frame400and the retracting lens frame401. The retracting lens frame401has the third lens group L3. The retracting lens frame401moves around the retraction shaft501bthat is substantially parallel to the optical axis, with respect to the OIS frame400during a transition period between an imaging enabled state and a housed state. The retracting lens frame401has at least three contact portions603. The three or more contact portions603come into contact with the OIS frame400at positions that are different from the retraction shaft501b. When the contact portions603come into contact with the OIS frame400, movement of the retracting lens frame401in the optical axis direction is restricted. At least one of the contact portions603is provided to the retracting lens frame401so that the angle formed by a line segment LN1 linking at least one of the contact portions603and the optical axis of the third lens group L3 and a line segment LN2 linking the retraction shaft501band the optical axis of the third lens group L3 is an obtuse angle.

With this lens barrel20, at least one of the contact portions603(603A,603A3) is provided to the retracting lens frame401so that the angle formed by the line segment LN1 linking the one or more contact portions603and the lens L3 and the line segment LN2 linking the retraction shaft501and the lens L3 is an obtuse angle. Consequently, at least one of the contact portions603(603A,603A3) can be disposed outside the retracting lens L3, so good vertical accuracy (inclination accuracy, tilt accuracy) of the retracting lens frame401(the retracting lens L3) can be reliably ensured. In other words, accuracy is easier to manage.

(2-2) This lens barrel20further comprises the thrust spring402. The thrust spring402is fixed to the OIS frame400, and biases the retracting lens frame401with respect to the OIS frame400. The thrust spring402brings at least two of the contact portions603into contact with the OIS frame400.

With this lens barrel20, because the thrust spring402biases the retracting lens frame401with respect to the OIS frame400, two or more of the contact portions603(603A to603C) can be brought into contact with the retracting lens frame401. This reliably ensures good vertical accuracy (inclination accuracy, tilt accuracy, etc.) of the retracting lens frame401(the retracting lens L3).

(2-3) This lens barrel20further comprises the rotary spring403. The rotary spring403is fixed to the OIS frame400, and biases the retracting lens frame401around the retraction shaft501b. The OIS frame400has the anti-rotation portion502. The anti-rotation portion502restricts movement of the retracting lens frame401by the rotary spring403. The anti-rotation portion502has at least one sloped face502athat is sloped with respect to the optical axis. When the retracting lens frame401is biased by the rotary spring403, one of the three or more contact portions603comes into contact with the sloped face502a, and this guides the retracting lens frame401toward the OIS frame400.

With this lens barrel20, when the retracting lens frame401is biased by the rotary spring403, one of the contact portions603(603C) hits the sloped face502aof the anti-rotation portion502, and the retracting lens frame401is guided toward the OIS frame400. This presses the retracting lens frame401toward the OIS frame400. Specifically, the contact portions603of the retracting lens frame401reliably come into contact with the OIS frame400.

(2-4) With this lens barrel20, at least one of the contact portions603is provided to the retracting lens frame401so that a straight line LN3, which passes through the optical axis of the third lens group L3 and is perpendicular to the line segment LN2 linking the retraction shaft501band the optical axis of the third lens group L3, is located between the retraction shaft501band the one or more contact portions603.

Consequently, at least one of the contact portions603(603A,603A3) can be disposed outside of the retracting lens L3, so good vertical accuracy (inclination accuracy, tilt accuracy) of the retracting lens frame401(the retracting lens L3) can be reliably ensured. In other words, accuracy is easier to manage.

(3) In prior art, the protrusions formed on the subordinate optical system holder (corresponds to the retracting lens frame) do not come into contact with the member supporting the subsidiary optical system holder between the imaging state and the retracted state. Accordingly, if some kind or external force or the like should be generated while the subsidiary optical system holder is moving from the imaging state to the retracted state, there is the risk that unwanted looseness or the like will occur in the subsidiary optical system holder.

The technology disclosed herein was conceived in light of the above problem, and it is an object of the present technology to allow the retracting lens frame to move stably from the imaging state to the retracted state.

The lens barrel disclosed herein comprises a support frame and a retracting lens frame. The retracting lens frame supports a lens, and moves around a retraction shaft substantially parallel to the optical axis, with respect to the support frame during a transition period between an imaging enabled state and a housed state. The retracting lens frame has at least three contact portions. The three or more contact portions come into contact with the support frame at positions that are different from the retraction shaft. The support frame has at least three rail portions. The three or more rail portions are formed at positions corresponding to the three or more contact portions during a transition period between the imaging enabled state and the housed state. When the contact portions come into contact with the rail portions, this restricts movement of the retracting lens frame in the optical axis direction.

The technology disclosed herein provides a lens barrel with which a retracting lens frame can move stably.

The technology disclosed herein provides a lens barrel with which good vertical accuracy can be reliably ensured for a retracting lens frame.

The configuration and effect discussed above will now be described in specific terms.

(3-1) This lens barrel20comprises the OIS frame400and the retracting lens frame401. The retracting lens frame401supports the third lens group L3. The retracting lens frame401moves around the retraction shaft501b, which is substantially parallel to the optical axis, with respect to the OIS frame400during a transition period between an imaging enabled state and a housed state. The retracting lens frame401has at least three contact portions603. The three or more contact portions603come into contact with the OIS frame400at positions that are different from the retraction shaft501b. The three or more rail portions503are formed at positions that are opposite the three or more contact portions603during a transition period between an imaging enabled state and a housed state. When the contact portions603hit the rail portions503, this restricts movement of the retracting lens frame401in the optical axis direction.

With this lens barrel20, the contact portions603are configured to come into contact with the rail portions503of the OIS frame400between the imaging enabled state and the retracted state. Consequently, even if some kind or external force or the like should be generated between the imaging enabled state (or retracted state) and the retracted state (or imaging enabled state), the retracting lens frame401can still be moved stably. In other words, the retracting lens frame401can be stably guided by the rail portions503between the imaging enabled state (or retracted state) and the retracted state (or imaging enabled state).

Thus forming the rail portions503on the OIS frame400stably ensures the proper orientation of the retracting lens frame401even if the OIS frame400has a complex shape (even f the portion corresponding to the contact portions603is uneven).

(3-2) This lens barrel20further comprises the thrust spring402. The thrust spring402is fixed to the OIS frame400, and biases the retracting lens frame401with respect to the OIS frame400. The thrust spring402brings at least two of the contact portions603into contact with the OIS frame400.

With this lens barrel20, because the thrust spring402biases the retracting lens frame401with respect to the OIS frame400, two or more of the contact portions603(603A to603C) can be brought into contact with the retracting lens frame401. This reliably ensures good vertical accuracy (inclination accuracy, tilt accuracy, etc.) of the retracting lens frame401(the retracting lens L3).

(3-3) This lens barrel20further comprises the rotary spring403. The rotary spring403is fixed to the OIS frame400, and biases the retracting lens frame401around the retraction shaft501b. The OIS frame400has an anti-rotation portion502. The anti-rotation portion502restricts movement of the retracting lens frame401by the rotary spring403. The anti-rotation portion502has at least one sloped face502athat is sloped with respect to the optical axis. When the retracting lens frame401is biased by the rotary spring403, one of the three or more contact portions603comes into contact with the sloped face502a, and this guides the retracting lens frame401toward the OIS frame400.

With this lens barrel20, when the retracting lens frame401is biased by the rotary spring403, one of the contact portions603(603C) hits the sloped face502aof the anti-rotation portion502, and the retracting lens frame401is guided toward the OIS frame400. This presses the retracting lens frame401toward the OIS frame400. Specifically, the contact portions603of the retracting lens frame401reliably come into contact with the OIS frame400.

(3-4) With this lens barrel20, when the rail portions503are viewed in the optical axis direction, the rail portions503are formed on the OIS frame400at positions outside the range of movement of the third lens group L3.

With this lens barrel20, the rail portions503are formed on a second main body portion500at a portion excluding the range of movement RM of the third lens group L3. Consequently, the retracting lens frame401is supported at three points at all times between the imaging enabled state (or retracted state) and the retracted state (or imaging enabled state).

(4) In the past, a lens barrel was disclosed in which a blur correction lens group chamber could be retracted outside of a fourth lens group chamber in a direction perpendicular to the optical axis (see Japanese Laid-Open Patent Application 2007-163961).

With this prior art, the blur correction lens group chamber (corresponds to a retracting lens frame) was shifted in a direction perpendicular to the optical axis by a blur correction mechanism in the imaging state. This reduced image blurring. In the housed state, this blur correction lens group chamber was retracted out of the fourth lens group chamber.

With this prior art, when image blurring is corrected in the imaging state, a spring that was more powerful than in the past had to be used to support the blur correction lens group chamber so that the blur correction lens group chamber would not shift in the retraction direction. Specifically, when the blur correction lens group chamber was rotated and retracted, a greater pressing force than in the past was necessary. Accordingly, when the blur correction lens group chamber was rotated, there was the risk that the portion supporting the blur correction lens group chamber, such as the blur correction mechanism part of a third lens group barrel (the rotary shaft of a diaphragm) would not be able to withstand this pressing force and would end up being deformed. That is, there was the risk that the operation of the third lens group barrel (OIS frame) would end up being unstable.

The technology disclosed herein was conceived in light of the above problems, and it is an object of the present technology to allow the OIS to operate stably even when a retracting lens frame is mounted to the OIS frame.

The lens barrel disclosed herein comprises a frame body, a support frame, and a retracting lens frame. The frame body has a restrictor. The support frame has a restricted portion. The movement of the support frame in the optical axis direction is restricted with respect to the frame body when the restricted portion is restricted by the restrictor, but the support frame still moves within a plane that is perpendicular to the optical axis with respect to the frame body. The retracting lens frame is supported by the support frame, and moves around a retraction shaft substantially perpendicular to the optical axis during a transition period between an imaging enabled state and a housed state. The retracting lens frame has a pressing portion that is pressed during the transition period between the imaging enabled state and the housed state. The support frame has a frame body contact portion that comes into contact with the frame body when the pressing portion is pressed. The frame body has a support frame contact portion that comes into contact with the frame body contact portion. When the pressing portion is pressed, the frame body contact portion and the support frame contact portion come into contact with each other, which reduces the load exerted on the restrictor and the restricted portion.

The technology disclosed herein provides a lens barrel with which stable OIS operation is possible.

The configuration and effect discussed above will now be described in specific terms.

(4-1) This lens barrel20comprises a shutter unit250, the OIS frame400, and the retracting lens frame401. The shutter unit250has a restrictor420. The OIS frame400has a restricted portion510. When the restricted portion510is restricted by the restrictor420, movement of the OIS frame400in the optical axis direction is restricted with respect to the shutter unit250, but the OIS frame400is configured to move within a plane that is perpendicular to the optical axis with respect to the shutter unit250. The retracting lens frame401is supported by the OIS frame400, and moves around a retraction shaft that is substantially parallel to the optical axis during the transition period between the imaging enabled state and the housed state.

The retracting lens frame401has a pressing portion605that is pressed during the transition period between the imaging enabled state and the housed state. The OIS frame400has a first stress diffuser511(frame body contact portion) that comes into contact with the shutter unit250when the pressing portion605is pressed. The shutter unit250has a second stress diffuser422(support frame contact portion) that comes into contact with the first stress diffuser511. When the pressing portion605is pressed, the first stress diffuser511and the second stress diffuser422come into contact with each other, which reduces the load exerted on the restrictor420and the restricted portion510.

With this lens barrel20, the first stress diffuser511(frame body contact portion) formed on the OIS frame400, and the second stress diffuser422formed on the shutter unit250are configured to come into contact with each other. Specifically, even if a very stiff rotary spring403is used to mount the retracting lens frame401to the OIS frame400, the pressing force generated when the retracting lens frame401is rotated, is diffused into a force transmitted from the restricted portion510of the OIS frame400to the restrictor420of the shutter unit250, and a force that is transmitted from the first stress diffuser511to the second stress diffuser422. Consequently, less load is exerted on the restrictor420of the shutter unit250and on the restricted portion510of the OIS frame400. Specifically, the optical axis direction component of the pressing force can be prevented from causing deformation or damage to the restrictor420of the shutter unit250and to the restricted portion510of the OIS frame400. This allows the OIS to operate stably.

(4-2) With this lens barrel20, the first stress diffuser511is provided to the OIS frame400at a position closer to the pressing portion605than the restricted portion510.

With this lens barrel20, the first stress diffuser511is provided to the OIS frame400at a position that is closer to the pressing portion605than the restricted portion510. Accordingly, when the first stress diffuser511comes into contact with the second stress diffuser422, the force transmitted from the first stress diffuser511to the second stress diffuser422becomes greater than the force transmitted from the restricted portion510to the restrictor420. Specifically, the force exerted on the restrictor420and the restricted portion510can be reduced.

(4-3) With this lens barrel20, when the pressing portion605of the retracting lens frame401is pressed, the contact portions603of the retracting lens frame401come into contact with the OIS frame400. The first stress diffuser511of the OIS frame400then comes into contact with the second stress diffuser422of the shutter unit250. This reduces the force exerted on the restrictor420and the restricted portion510.

Other Embodiments

(A) In the above embodiment, the lens barrel20comprised the third rectilinear frame130, but the third rectilinear frame130may be omitted.

(B) In the above embodiment, the second rectilinear frame120was disposed on the inside of the first rotary frame210, but this is not the only option. The second rectilinear frame120may be disposed on the outside of the first rotary frame210. That is, the second rectilinear frame120should be disposed on the inside of the first rectilinear frame110.

(C) In the above embodiment, the lens barrel20comprised the first to fifth lens groups L1 to L5, but this is not the only option. The lens barrel20should at least comprise the first lens group L1.

(D) In the above embodiment, the lens barrel20comprised a three-stage telescoping zoom mechanism, but this is not the only option. The lens barrel20may have a telescoping mechanism of more than three stages.

(E) In the above embodiment, the cam grooves b were formed in one of two frames, and the cam protrusions B were formed in the other frame, but this is not the only option. The cam protrusions B may be formed in one of the two frames, and the cam grooves b formed in the other frame. Or, the cam grooves b and the cam protrusions B may be formed in each of the two frames.

(F) In the above embodiment, the rectilinear grooves “a” were formed in one of two frames, and the rectilinear protrusions A were formed in the other frame, but this is not the only option. The rectilinear protrusions A may be formed in one of two frames, and the rectilinear grooves a in the other frame. Or, the rectilinear grooves “a” and the rectilinear protrusions A may be formed in each of the two frames.

(G) In the above embodiment, the bayonet grooves e were formed in one of two frames, and the bayonet protrusions E were formed in the other frame, but this is not the only option. The bayonet protrusions E may be formed in one of two frames, and the bayonet grooves e in the other frame. Or, the bayonet grooves e and the bayonet protrusions E may be formed in each of the two frames.

(H) In the above embodiment, the third lens group L3 was retracted to the outside in the radial direction of the fourth and fifth lens groups L4 and L5, but this is not the only option. The third lens group L3 may be disposed ahead of the fourth and fifth lens groups L4 and L5 in the retracted state.

(I) In the above embodiment, an example was given in which the retraction shaft501(retraction shaft501b) was provided to the OIS frame400and the shaft support601was provided to the retracting lens frame401, but the shaft support601may be provided to the OIS frame400, and the retraction shaft501(retraction shaft501b) to the retracting lens frame401.

(J) In the above embodiment, as shown inFIG. 12, an example was given in which the anti-rotation portion502of the OIS frame400had a concave shape, and the third contact portion603C of the retracting lens frame401came into contact with the sloped face502aof the anti-rotation portion502. Instead, as shown inFIG. 23, the third contact portion603C of the retracting lens frame401may come into contact with two side faces512ain a concave portion512of an anti-rotation portion502′. In this case, the two side faces512aof the concave portion512are inclined and opposite each other. More specifically, the two side faces512aof the concave portion512are formed so as to move closer to together toward the bottom512bof the concave portion512. This allows the retracting lens frame401to be positioned more reliably with respect to the OIS frame400.

General Interpretation of Terms

The term “configured” as used herein to describe a component, section, or part of a device implies the existence of other unclaimed or unmentioned components, sections, members or parts of the device to carry out a desired function.

While only selected embodiments have been chosen to illustrate the present technology, it will be apparent to those skilled in the art from this disclosure that various changes and modifications can be made herein without departing from the scope of the technology as defined in the appended claims. For example, the size, shape, location or orientation of the various components can be changed as needed and/or desired. Components that are shown directly connected or contacting each other can have intermediate structures disposed between them. The functions of one element can be performed by two, and vice versa. The structures and functions of one embodiment can be adopted in another embodiment. It is not necessary for all advantages to be present in a particular embodiment at the same time. Every feature which is unique from the prior art, alone or in combination with other features, also should be considered a separate description of further technologies by the applicant, including the structural and/or functional concepts embodied by such feature(s). Thus, the foregoing descriptions of the embodiments according to the present technologies are provided for illustration only, and not for the purpose of limiting the technology as defined by the appended claims and their equivalents.

INDUSTRIAL APPLICABILITY

The technology disclosed herein can be widely applied to lens barrels.