JP5707942B2 - Lens barrel and camera - Google Patents

Description

  The present invention relates to a lens barrel and a camera equipped with the same.

  There is a zoom lens that includes a plurality of lenses and changes a focal length and the like by moving a lens holding member that holds the lenses. Some zoom lenses are provided with a structure that reduces rattling between the lens holding member and the straight guide groove that guides the lens holding member in order to improve the positioning accuracy of the lens. In such a structure, one end of the spring is brought into contact with the rectilinear guide groove, and the other end of the spring is brought into contact with the lens holding member, so that the lens holding member is loose, and the lens holding member Is configured to move along the straight guide groove (for example, see Patent Document 1).

JP 2009-222873 A

  In the lens barrel described in Patent Document 1, rattling between the lens holding member and the rectilinear guide can be reduced. However, an impact may be applied to the lens when the lens holding member moves and collides with another member due to an impact from the outside.

  An object of the present invention is to provide a lens barrel having suitable optical characteristics, and a camera including the lens barrel.

  The present invention solves the above problems by the following means. In addition, in order to make an understanding easy, although the code | symbol corresponding to embodiment of this invention is attached | subjected and demonstrated, it is not limited to this.

The invention of claim 1 comprises a plurality of holds the first lens of the optical system having a lens, a first lens retaining member movable in an optical axis Direction of the first lens, It said abutment member being spaced in the first lens holding member or al the optical axis direction, disposed between the first lens holding member and said abutment member, said first lens and interference prevention member which can abut against the abutment member to follow the movement of the optical axis direction of the holding member is moved in the optical axis direction, the interference between the first lens holding member It is disposed between the prevention member, the first lens holding member and the interference prevention member and the elastic member that generates an elastic force in a direction away, provided corresponding to the first lens holding member The first cam groove and the second cam groove provided corresponding to the interference preventing member are provided along a direction intersecting the optical axis. Had cam cylinder, by rotation of the cam barrel, the contact of the interference prevention member by moving the optical axis direction integrally with the first lens holding portion Zai及 beauty the interference prevention member a drive Organization can be abutted against the section member, a lens barrel, characterized in that it comprises a.
According to a second aspect of the invention, a lens barrel according to claim 1, wherein the abutment member includes a second for holding the second lens of the optical system having a plurality of lenses it is a lens holding member, a lens barrel according to claim.
According to a third aspect of the invention, a lens barrel according to claim 2, decentering sensitivity of the first lens comprises a said strong that, than the sensitivity to decentration of the second lens This is a lens barrel .
Invention of claim 4, a lens barrel according to claim 3, wherein the second lens holding member is a lens, characterized in that, being constituted to be movable in the optical axis Direction It is a lens barrel .
The invention described in claim 5 is the lens barrel according to claim 2 or 3, wherein the second lens holding member is provided with, characterized in that is immovably fixed to the optical axis Direction This is a lens barrel .
Invention of claim 6, a lens barrel according to any one of claims 2 to 5, in a state in which the interference preventing member is in contact with the second lens holding member, wherein the optical axis direction distance direction in the in light axis to the surface of the second lens from the surface of the first lens facing the surface of the first lens, at the time the elastic member is the shortest, it the first lens surface and the second lens surface is a distance that does not abut, a lens barrel according to claim.
The invention of claim 7 is a camera that comprising the lens barrel according to any one of claims 1 to 6.

  According to the present invention, it is possible to provide a lens barrel having suitable optical characteristics.

It is a conceptual diagram of a camera provided with a lens barrel in a wide-angle state that is an embodiment of the present invention. It is sectional drawing in the state which the interference prevention member and the 2nd lens holding frame contact | abutted in the telephoto state of a lens-barrel. It is an image figure which shows the eccentric sensitivity of the 1st lens and 2nd lens in a lens barrel.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a conceptual diagram of a camera 1 including a lens barrel 10 in a wide angle state according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the lens barrel 10 in a telephoto state in which the interference preventing member 17 and the second lens holding frame 42 are in contact with each other.

  1 and 2 and the drawings described below are provided with an XYZ orthogonal coordinate system for easy explanation and understanding. In this coordinate system, when the photographer shoots a horizontally long image with the optical axis OA being horizontal, the direction toward the left side as viewed from the photographer at the position of the camera 1 (hereinafter referred to as a positive position) is the X axis plus direction, A direction toward the upper side at the position is a Y-axis plus direction, and a direction toward the subject at the positive position is a Z-axis plus direction. In the following description, the direction parallel to the optical axis OA is referred to as “front-rear”, the subject side is referred to as “front side”, and the other end side is referred to as “back side”. Further, the movement in the direction parallel to the optical axis OA is referred to as “straight forward”, and the movement around the optical axis OA is referred to as “rotation”.

  The camera 1 is a digital camera including a camera body 2 and a lens barrel 10 that is detachably coupled to the camera body 2 via a mount unit 3. The present invention is not limited to a digital camera, and can be applied to, for example, a still camera using a film.

The camera body 2 includes an image sensor 21 that converts an optical subject image into an electrical signal.
Although described in detail later, the lens barrel 10 includes a plurality of lenses (L1, L2, L3, L4, and L5) that form an imaging optical system, and the incident subject light is input to the imaging element 21 of the camera body 2. To form an image.
The camera 1 having the above configuration converts the subject light image formed by the lens barrel 10 into an electrical signal by the image pickup device 21 and records it as image information in a memory (not shown) provided in the camera body 2.

Next, the lens barrel 10 according to the present embodiment will be described.
The lens barrel 10 is a so-called zoom lens that can change the combined focal length of the optical system. FIG. 1 shows a state in which the focal length of the lens barrel 10 is the shortest (hereinafter referred to as a wide angle state). FIG. 2 shows a state in which the interference preventing member 17 and the second lens holding frame 42 are in contact with each other in a state where the focal length of the lens barrel 10 is the longest (hereinafter referred to as a telephoto state).

As described above, the lens barrel 10 has an imaging optical system having a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, and a fifth lens L5 as a plurality of lenses. .
The first lens L1, the second lens L2, the third lens L3, the fourth lens L4, and the fifth lens L5 are arranged such that the fourth lens L4, the fifth lens L5, The first lens L1, the second lens L2, and the third lens L3 are arranged in this order.

The fourth lens L4 is supported on the inner peripheral side of the end portion on the front side of the first fixed cylinder 11 to be described later. The fifth lens L5 is supported on the inner peripheral side of the first fixed cylinder 11 while being held by the fifth lens holding frame 45 on the back side of the fourth lens L4, and functions as a focus lens.
The fifth lens holding frame 45 is configured to be movable along the direction of the optical axis OA.

  The first lens L1, the second lens L2, and the third lens L3 are held in the first lens holding frame 41, the second lens holding frame 42, and the third lens holding frame 43, respectively. It is supported on the circumferential side. Although described in detail later, the first lens holding frame 41 is configured to be movable along the direction of the optical axis OA. The 2nd lens holding frame 42 and the 3rd lens holding frame 43 are being fixed to the inner peripheral side of the 1st fixed cylinder 11 mentioned later so that a movement in the optical axis OA direction is impossible. The first lens holding frame 41, the second lens holding frame 42, and the third lens holding frame 43 are arranged apart from each other in the optical axis OA direction.

The lens barrel 10 includes a first fixed cylinder 11, a second fixed cylinder 12, a cam cylinder 13, a focus cylinder 14, a focus operation ring 15, a zoom operation ring 16, and an interference prevention member 17. ing. Each of these members is formed in a cylindrical shape.
The first fixed cylinder 11 is formed long over the entire region of the lens barrel 10 in the direction of the optical axis OA. The first fixed cylinder 11 includes a large-diameter portion 111 on the front surface side (Z-axis plus side) and a small-diameter portion 112 on the back surface side (Z-axis minus side). The large diameter portion 111 includes a front side end portion 111A and a double cylindrical portion 111B.

  The front side end portion 111 </ b> A is formed in a cylindrical shape at the front side end portion of the large diameter portion 111. The double cylindrical portion 111B is formed continuously to the front side end portion 111A on the back side of the front side end portion 111A. The double cylindrical portion 111B includes an inner cylindrical portion 111C and an outer cylindrical portion 111D that is positioned concentrically outside the inner cylindrical portion 111C. A focus cylinder 14, which will be described later, is rotatably disposed between the inner cylinder part 111C and the outer cylinder part 111D along the outer peripheral surface of the inner cylinder part 111C.

The large-diameter portion 111 of the first fixed cylinder 11 is supported in a state where the fourth lens L4 is fixed to the inner peripheral side of the front side end portion 111A, and the inner diameter of the inner cylindrical portion 111C on the back side with respect to the front side end portion 111A. On the circumferential side, the fifth lens holding frame 45 is supported so as to be movable in the direction of the optical axis OA.
The small diameter part 112 of the first fixed cylinder 11 rotatably supports the cam cylinder 13 on the inner peripheral side on the front surface side of the small diameter part 112, and the second lens holding frame 42 on the inner peripheral side on the back side of the cam cylinder 13. Is supported in a fixed state, and the third lens holding frame 43 is supported in a fixed state on the inner peripheral side on the back side of the second lens holding frame. The cam cylinder 13 supports the first lens holding frame 41 and the interference prevention member 17 on the inner peripheral side of the cam cylinder 13 so as to be movable in the direction of the optical axis OA.

The second fixed cylinder 12 is located concentrically outside the first fixed cylinder 11 on the back side of the lens barrel 10, and is fixed to the first fixed cylinder 11 at the back side end. A lens mount 31 that is coupled to the camera body 2 is provided at the rear side end portions of the first fixed cylinder 11 and the second fixed cylinder 12.
The first fixed cylinder 11 and the second fixed cylinder 12 are joined at the base end (end on the back side) to form the base of the lens barrel 10 and hold other components.

The focus operation ring 15 and the zoom operation ring 16 are connected to the first fixed cylinder 11 and the second fixed cylinder 12 so as to be relatively rotatable. The focus operation ring 15 is connected to the front surface side (Z-axis plus side) in the vicinity of the center portion of the lens barrel 10 in the optical axis OA direction so as to be rotatable relative to the first fixed tube 11. The zoom operation ring 16 is coupled to the second fixed cylinder 12 so as to be rotatable relative to the rear side (Z-axis minus side) of the focus operation ring 15 near the center of the lens barrel 10 in the optical axis OA direction. ing.
The large-diameter portion 111, the second fixed cylinder 12, the focus operation ring 15, and the zoom operation ring 16 of the first fixed cylinder 11 form the outer shape of the lens barrel 10.

  A focus side rectilinear guide groove (not shown) is provided in the inner cylinder portion 111C of the large diameter portion 111 of the first fixed cylinder 11 along the optical axis OA direction. The focus-side straight guide groove is provided over the movement range of the fifth lens holding frame 45 in the optical axis OA direction.

  The focus tube 14 is provided with a focus cam groove (not shown) along the direction intersecting the optical axis OA direction corresponding to the focus-side straight guide groove of the first fixed tube 11. The focus cam groove is provided corresponding to the movement range of the fifth lens holding frame 45 in the optical axis OA direction. The focus cam groove of the focus cylinder 14 is formed so that the position in the optical axis OA direction is displaced in a predetermined relationship in the circumferential direction.

  A fifth holding frame cam pin 25 is provided on the outer peripheral surface of the fifth lens holding frame 45 so as to protrude in a direction intersecting the optical axis OA direction. The fifth holding frame cam pin 25 is slidably fitted into the focus cam groove of the focus cylinder 14 through the focus side straight guide groove of the first fixed cylinder 11. As a result, the fifth lens holding frame 45 is driven to move in the direction of the optical axis OA along the focus-side straight guide groove by the rotation of the focus cylinder 14.

  As described above, the focus operation ring 15 is provided on the outer peripheral side near the center of the lens barrel 10 so as to be rotatable in the circumferential direction with respect to the first fixed cylinder 11. The focus operation ring 15 is engaged with the focus cylinder 14 at an engaging portion (not shown), and can be rotated integrally with the focus cylinder 14. The focus operation ring 15 performs the focus operation by moving the fifth lens holding frame 45 along the optical axis OA direction.

  On the front side of the small-diameter portion 112 of the first fixed cylinder 11, a zoom-side straight guide groove (not shown) is provided along the optical axis OA direction. The zoom-side rectilinear guide groove is provided over a range of movement in the optical axis OA direction of the first lens holding frame 41 and an interference preventing member 17 described later.

  Further, the cam cylinder 13 is provided with a zoom cam groove and an interference prevention cam groove (not shown) along the direction intersecting the optical axis OA direction corresponding to the zoom-side straight guide groove of the first fixed cylinder 11. . The zoom cam groove and the interference prevention cam groove are provided corresponding to the movement range of the first lens holding frame 41 and the interference prevention member 17 in the optical axis OA direction. The zoom cam groove and the interference prevention cam groove of the cam cylinder 13 are formed such that the positions in the optical axis OA direction are displaced in a predetermined relationship in the circumferential direction.

  In the present embodiment, the zoom cam groove and the interference prevention cam groove of the cam cylinder 13 are formed to be inclined with respect to the optical axis OA in a state where they are separated from each other by a predetermined distance in the direction of the optical axis OA.

  The distance between the first lens holding frame 41 and the interference prevention member 17 is appropriately set according to the pitch between the zoom cam groove and the interference prevention cam groove (the length between the groove and the groove separated in the optical axis OA direction). By varying the pitch between the zoom cam groove and the interference prevention cam groove in the optical axis OA direction, the distance between the first lens holding frame 41 and the interference prevention member 17 can be varied.

  A first cam pin 26 is provided on the outer peripheral surface of the first lens holding frame 41 so as to protrude in a direction intersecting with the optical axis OA direction. The first cam pin 26 penetrates through the zoom cam groove of the cam cylinder 13 and is slidably fitted in the zoom side straight guide groove of the first fixed cylinder 11. Thus, the first lens holding frame 41 is driven to move in the direction of the optical axis OA along the zoom-side straight guide groove by the rotation of the cam cylinder 13.

  The interference preventing member 17 is disposed between the first lens holding frame 41 and the second lens holding frame 42 in the optical axis OA direction. The interference preventing member 17 is formed in a short cylinder shape having a predetermined length in the optical axis OA direction. The size of the outer diameter of the interference preventing member 17 is substantially the same as the inner diameter of the cam cylinder 13.

A second cam pin 27 is provided on the outer peripheral surface of the interference preventing member 17 so as to protrude in a direction intersecting the optical axis OA direction. The second cam pin 27 passes through the interference prevention cam groove of the cam cylinder 13 and is slidably fitted in the zoom side linear guide groove of the first fixed cylinder 11.
The interference preventing member 17 follows the movement of the first lens holding frame 41 in the optical axis OA direction by the rotation of the cam cylinder 13 and is moved in the optical axis OA direction along the zoom-side straight guide groove. ing.

  As described above, the zoom operation ring 16 is provided on the outer peripheral side near the center of the lens barrel 10 so as to be rotatable in the circumferential direction with respect to the second fixed cylinder 12. The zoom operation ring 16 engages with the cam cylinder 13 at an engaging portion (not shown), and can rotate integrally with the cam cylinder 13. The zoom operation ring 16 performs a zoom operation by moving the first lens holding frame 41 in the direction of the optical axis OA.

  The configuration in which the interference preventing member 17 is moved in the direction of the optical axis OA following the first lens holding frame 41 is performed by the drive mechanism 30. The drive mechanism 30 includes a zoom-side straight guide groove of the first fixed cylinder 11, a zoom cam groove and an interference prevention cam groove of the cam cylinder 13, a first cam pin 26, a second cam pin 27, and a zoom operation ring 16. Has been.

  As described above, the first lens holding frame 41 and the interference prevention member 17 are configured to be movable in the direction of the optical axis OA by the drive mechanism 30. The drive mechanism 30 can bring the interference prevention member 17 into contact with the second lens holding frame 42 by moving the first lens holding frame 41 and the interference prevention member 17 along the optical axis OA direction. Yes.

  An elastic member 18 is disposed between the first lens holding frame 41 and the interference prevention member 17. The elastic member 18 is configured by, for example, a coil spring or a wave washer. In addition, as the elastic member 18, about three coil springs may be provided along the circumferential direction, or a coil spring having the same diameter as the inner diameter of the cam cylinder 13 may be used.

  The elastic member 18 is in a state where one end is in contact with the first lens holding frame 41, and the other end is in contact with the interference preventing member 17, and between the first lens holding frame 41 and the interference preventing member 17. Placed in. The elastic member 18 generates an elastic force in a direction in which the first lens holding frame 41 and the interference preventing member 17 are separated from each other.

  Here, the elastic force generated by the elastic member 18 is caused by the distance between the first lens holding frame 41 and the interference preventing member 17. Therefore, the elastic force generated by the elastic member 18 can be made different for each position in the optical axis OA direction by adjusting the pitch between the zoom cam groove and the interference prevention cam groove at the position in the optical axis OA direction.

  The elastic member 18 removes the play between the zoom cam groove and the first cam pin 26 and the play between the interference prevention cam groove and the second cam pin 27, and the first lens holding frame 41 and the interference prevention member in the optical axis OA direction. As a result, the backlash of the first lens holding frame 41 can be reduced. Therefore, the positioning accuracy of the first lens holding frame 41 in the optical axis OA direction can be improved.

  Further, since the elastic member 18 is disposed between the interference preventing member 17 and the third lens holding frame 43, when the interference preventing member 17 collides with the second lens holding frame 42, the elastic member 18 absorbs the impact. It also has a function as a damper.

  The drive mechanism 30 integrally moves the first lens holding frame 41, the interference prevention member 17, and the elastic member 18 in the direction of the optical axis OA in a state in which the backlash of the first lens holding frame 41 is prevented by the elastic member 18. .

  By the drive mechanism 30, the first lens holding frame 41, the interference preventing member 17, and the elastic member 18 are integrally moved in the direction of the optical axis OA. The interference preventing member 17 may come into contact with the second lens holding frame 42. Here, the distance in the optical axis OA direction at the center of the optical axis OA from the surface of the first lens L1 to the surface of the second lens L2 is a distance at which the surface of the first lens L1 and the surface of the second lens L2 do not contact each other. It has become a relationship. Specifically, the surface of the first lens L1 and the surface of the second lens L2 are configured not to contact each other even when the elastic member 18 is shortest. The shortest time of the elastic member 18 is when the first lens holding frame 41 is closest to the second lens holding frame 42.

  In the present embodiment, the first lens L1 is arranged to face the second lens L2. The surface of the first lens L1 that faces the second lens L2 is formed to protrude toward the second lens L2. Further, the surface of the second lens L2 facing the first lens L1 is formed so as to protrude toward the first lens L1. That is, the mutually opposing surfaces of the first lens L1 and the second lens L2 protrude in the direction in which they approach each other. Even in such a case, when the first lens holding frame 41 is closest to the second lens holding frame 42, the distance relationship between the surface of the first lens L1 and the surface of the second lens L2 does not come into contact. It has become.

The lens barrel 10 configured as described above operates as follows.
When the focus operation ring 15 is rotated in the circumferential direction with respect to the first fixed cylinder 11, the focus cylinder 14 rotates integrally with the focus operation ring 15 and rotates in the circumferential direction with respect to the first fixed cylinder 11. As a result, the fifth holding frame cam pin 25 provided on the fifth lens holding frame 45 moves along the focus-side rectilinear guide groove of the first fixed tube 11 and the focus cam groove of the focus tube 14, and the first fixed tube. 11 moves along a focus-side straight guide groove provided in 11. As a result, the fifth lens holding frame 45 (the fifth lens L5) moves along the direction of the optical axis OA.

  Further, in the wide-angle state of the lens barrel 10 shown in FIG. 1, the zoom operation ring 16 is moved with respect to the first fixed barrel 11 so that the first lens holding frame 41 is moved to the back side along the optical axis OA direction. Rotate in one direction of the circumferential direction. Accordingly, the cam cylinder 13 rotates in the circumferential direction integrally with the zoom operation ring 16 and rotates with respect to the first fixed cylinder 11.

  When the cam cylinder 13 rotates in the circumferential direction with respect to the first fixed cylinder 11, the first cam pin 26 protruding from the outer peripheral surface of the first lens holding frame 41 and the first protruding from the outer peripheral surface of the interference preventing member 17 are provided. The two cam pins 27 move along the zoom cam groove and the interference prevention cam groove provided in the cam cylinder 13, and move along the zoom-side straight guide groove provided in the first fixed cylinder 11.

  As a result, the first lens holding frame 41 (first lens L1) moves to the back side along the direction of the optical axis OA as the focus operation ring 15 rotates in the circumferential direction. Then, the lens barrel 10 is in the telephoto state. Further, when the zoom operation ring 16 is rotated in the reverse direction from the telephoto state, the first lens holding frame 41 (the first lens L1) is rotated by rotating the cam cylinder 13 integrally with the zoom operation ring 16 in the circumferential direction. Then, it moves to the front side along the direction of the optical axis OA and enters the wide angle state shown in FIG.

In the present embodiment, the interference preventing member 17 that moves following the movement of the first lens holding frame 41 is disposed between the first lens holding frame 41 and the second lens holding frame 42. Further, the elastic member 18 is disposed between the first lens holding frame 41 and the interference preventing member 17.
The interference preventing member 17 and the elastic member 18 prevent the first lens holding frame 41 from rattling. Therefore, the first lens holding frame 41 moves in the direction of the optical axis OA in a state where rattling is prevented. Therefore, the interference preventing member 17 and the elastic member 18 can improve the positioning accuracy of the first lens L1 in the optical axis OA direction.

In the present embodiment, the interference preventing member 17 is configured to be able to contact the second lens holding frame 42 when moved in the direction of the optical axis OA by the drive mechanism 30.
In the wide-angle state of the lens barrel 10 shown in FIG. 1, an impact may be applied to the lens barrel 10 from the outside. Depending on the magnitude and direction of impact applied to the lens barrel 10, the first lens holding frame 41 may move to the back side in the direction of the optical axis OA along the zoom-side straight guide groove.

When the first lens holding frame 41 moves in the optical axis OA direction, the interference preventing member 17 follows and moves in the optical axis OA direction. That is, the first lens holding frame 41, the interference preventing member 17, and the elastic member 18 are integrally moved in the direction of the optical axis OA.
Here, the interference preventing member 17 is configured to be able to contact the second lens holding frame 42. For this reason, the interference preventing member 17 is placed on the second lens holding frame 42 depending on the distance relationship between the first lens holding frame 41 and the second lens holding frame 42, the relationship of the movement amount due to the impact of the first lens holding frame 41, and the like. There may be contact.

  In particular, in the telephoto state shown in FIG. 2 in which the first lens L1 is brought close to the second lens L2 by zooming from the wide angle state shown in FIG. Since the distance from the lens holding frame 42 is short, the possibility that the interference preventing member 17 collides (contacts) with the second lens holding frame 42 is increased.

Therefore, in the telephoto state of the lens barrel 10 shown in FIG. 2, an impact is applied from the outside, the first lens holding frame 41 moves toward the second lens holding frame 42, and the interference preventing member 17 is moved to the second position. The lens holding frame 42 may collide (contact).
In such a case, the interference preventing member 17 is disposed between the first lens holding frame 41 and the second lens holding frame 42. For this reason, the first lens holding frame 41 does not contact the second lens holding frame 42, and the interference preventing member 17 collides (contacts) with the second lens holding frame 42. Thereby, the impact to the 1st lens L1 hold | maintained at the 1st lens holding frame 41 can be reduced.

  Further, the elastic member 18 is disposed between the first lens holding frame 41 and the interference preventing member 17. Therefore, the impact on the first lens L1 held by the first lens holding frame 41 can be absorbed, and the impact on the first lens L1 can be reduced.

  Here, a large impact is applied to the lens barrel 10 of the present invention, and the first lens holding frame 41 is moved most greatly to the back side in the optical axis OA direction, and the first lens holding frame 41 is moved to the second position. The shortest time of the elastic member 18 closest to the lens holding frame 42 is assumed. In this case, the lens barrel 10 of the present invention has the surface of the first lens L1 and the second lens L2 at the shortest time of the elastic member 18 in a state where the interference preventing member 17 is in contact with the second lens holding frame 42. It has the relationship of the distance which the surface does not contact | abut. As a result, the first lens L1 and the second lens L2 are prevented from contacting each other.

As described above, this embodiment has the following effects.
(1) The lens barrel 10 is moved following the movement of the first lens holding frame 41 and can be brought into contact with the second lens holding frame 42. And an elastic member 18 disposed between the members 17. Thereby, it is possible to reduce the impact on the first lens L1 even when an impact is applied from the outside while reducing the backlash of the first lens holding frame 41.

(2) The second lens holding frame 42 is fixed to the first fixed cylinder 11. Therefore, when an impact is applied from the outside, the impact on the second lens L2 held by the second lens holding frame 42 can be reduced, and the impact on the first lens L1 can be reduced. .

(3) In a state where the interference preventing member 17 is in contact with the second lens holding frame 42, the distance is such that the surface of the first lens L1 and the surface of the second lens L2 do not contact when the elastic member 18 is shortest. . Therefore, it is possible to prevent the first lens L1 and the second lens L2 from coming into contact with each other when the first lens holding frame 41 is the shortest of the elastic member 18 closest to the second lens holding frame 42. Thereby, even when an impact is applied from the outside, the impact on the first lens L1 can be further reduced.

(Deformation)
The present invention is not limited to the above-described embodiment, and various modifications and changes as described below are possible, and these are also within the scope of the present invention.

(1) In the present embodiment, the form in which the second lens holding frame 42 is fixed to the first fixed cylinder 11 has been described, but the present invention is not limited to this. The second lens holding frame 42 may be configured to be movable in the optical axis OA direction. In this case, it is preferable that the decentering sensitivity of the first lens L1 is better than the decentering sensitivity of the second lens L2.
Here, the eccentric sensitivity will be described with reference to the drawings. FIG. 3 is an image diagram showing the eccentric sensitivity of the first lens L1 and the second lens L2 in the lens barrel 10. As shown in FIG. FIG. 3 shows the relationship between the amount of lens decentering and MTF (Modulation Transfer Function). MTF is an index for evaluating lens performance, and expresses as a spatial frequency characteristic how accurately the contrast of a subject can be reproduced in order to know the imaging performance of the lens.
“Decent sensitivity is good” means that when the same amount of decentration is applied to the optical system, for example, the MTF value deteriorates frequently. On the other hand, good decentration sensitivity means that when the same amount of decentration is added to the optical system, for example, there is little deterioration in the MTF value or the like.
As shown in FIG. 3, when the first lens L1 has the same amount of decentration as the second lens L2, the MTF value is largely deteriorated. Therefore, in the present embodiment, the decentering sensitivity of the first lens L1 is better than the decentering sensitivity of the second lens L2.
In this case, even when an impact is applied from the outside, even when the second lens holding frame 42 is configured to be movable while reducing the impact on the first lens L1 having high eccentricity sensitivity. Deterioration of the optical characteristics of the second lens L2 can be reduced because the decentration sensitivity held by the second lens holding frame 42 is good.

(2) In the present embodiment, the contact member that is spaced apart from the first lens holding frame 41 in the optical axis OA direction is configured by the second lens holding frame 42, but is not limited thereto. For example, the contact member may be a member constituting a diaphragm mechanism in the lens barrel 10.

(3) In the present embodiment, the present invention is applied to the first lens holding frame 41 that is moved to perform a zoom operation. However, the application site of the present invention is not limited to this, and may be applied to a focus lens holding frame moved to perform a focus operation.

(4) Furthermore, in the present embodiment, the detachable lens barrel has been described, but the present invention is not limited to this, and may be applied to a camera in which the camera body and the lens barrel are integrated.

  In addition, although embodiment and a deformation | transformation form can also be used in combination as appropriate, detailed description is abbreviate | omitted. Further, the present invention is not limited to the embodiment described above.

  1: camera, 2: camera body, 21: imaging element, 10: lens barrel, 11: first fixed barrel, 12: second fixed barrel, 13: cam barrel, 14: focus barrel, 15: focus operation ring, 17: interference prevention member, 18: elastic member, 30: drive mechanism, 41: first lens holding frame, 42: second lens holding frame, L1: first lens, L2: second lens, L3: third lens, L4: fourth lens, L5: fifth lens, OA: optical axis

Claims (7)

A first lens holding member that holds the first lens of the optical system having a plurality of lenses and is movable in the optical axis direction of the first lens;
An abutting member disposed away from the first lens holding member in the optical axis direction;
It is arranged between the first lens holding member and the contact member, and can move in the optical axis direction following the movement of the first lens holding member in the optical axis direction so as to contact the contact member An interference prevention member,
An elastic member disposed between the first lens holding member and the interference preventing member, and generating an elastic force in a direction in which the first lens holding member and the interference preventing member are separated from each other;
A cam cylinder in which a first cam groove provided corresponding to the first lens holding member and a second cam groove provided corresponding to the interference preventing member are provided along a direction intersecting the optical axis. The interference prevention member is brought into contact with the contact member by integrally moving the first lens holding member and the interference prevention member in the optical axis direction by rotation of the cam cylinder. Possible drive mechanism,
A lens barrel comprising: The lens barrel according to claim 1,
The contact member is a second lens holding member that holds a second lens of the optical system having the plurality of lenses;
A lens barrel characterized by The lens barrel according to claim 2,
The decentering sensitivity of the first lens is better than the decentering sensitivity of the second lens;
A lens barrel characterized by The lens barrel according to claim 3,
The second lens holding member is configured to be movable in the optical axis direction;
A lens barrel characterized by The lens barrel according to claim 2 or 3,
The second lens holding member is fixed so as not to move in the optical axis direction;
A lens barrel characterized by The lens barrel according to any one of claims 2 to 5,
The light at the center of the optical axis from the surface of the first lens to the surface of the second lens facing the surface of the first lens in a state where the interference preventing member is in contact with the second lens holding member. The axial distance is a distance at which the surface of the first lens and the surface of the second lens do not contact when the elastic member is shortest,
A lens barrel characterized by   A camera comprising the lens barrel according to claim 1.

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