JP2010169938A - Lens-barrel and optical equipment - Google Patents

Abstract

An optical axis adjustment operation can be facilitated without increasing the number of parts.
A holding frame (122b) for holding an optical system (121b), an elastic body (208) provided outside the holding frame (122b), and a holding frame (122b) facing the elastic body (208). The holding frame (122b) includes a first inclined surface (190a) that is pressed by the pressing member (190) and extends in a direction intersecting the optical axis L. .
[Selection] Figure 1

Description

  The present invention relates to a lens barrel and an optical apparatus.

  Conventionally, there has been an optical element holding structure for adjusting the parallel eccentricity of a first group barrel held integrally with an eccentric ring by pushing and pulling three push screws arranged at equal intervals in the circumferential direction of the lens holding portion. It is known (see the following publication).

JP 2006-91153 A

  However, in the above optical element holding structure, in order to adjust the optical axis, the three push screws must be loosened or tightened, and the adjustment work is complicated. If the lens is cracked and tightened, the lens may be tilted or detached due to vibration or impact.

  The present invention has been made in view of such circumstances, and a problem thereof is to provide a lens barrel capable of facilitating optical axis adjustment work.

  In order to solve the above-mentioned problems, a first aspect of the present invention includes a holding frame that holds an optical system, an elastic body that is provided outside the holding frame, and a pressing member that presses the holding frame toward the elastic body. The holding frame includes a first inclined surface that is pressed by the pressing member and extends in a direction intersecting the optical axis.

  According to a second aspect of the present invention, in the lens barrel according to the first aspect, the holding frame is pressed in a direction different from the pressing direction of the pressing member, and the holding frame is fixed between the pressing member and the lens barrel. The holding frame pressed by the fixing member is a second inclined surface extending in a direction intersecting the optical axis.

  According to a third aspect of the present invention, in the lens barrel according to the second aspect, the first inclined surface and the second inclined surface have the same direction intersecting the optical axis.

  According to a fourth aspect of the present invention, in the lens barrel according to any one of the first to third aspects, the lens barrel is provided opposite to the outer periphery of the holding frame, and the holding frame is fixed in a direction along the optical axis. A cylindrical member having a body portion on the inner periphery, and the first inclined surface of the holding frame is formed so that a direction opposite to the body portion intersects the optical axis. It is characterized by.

  According to a fifth aspect of the present invention, in the lens barrel according to any one of the first to fourth aspects, the pressing member can be moved forward or backward along a direction orthogonal to the optical axis of the optical system. The position of the holding frame is adjusted by the forward or backward movement of the pressing member.

  A sixth aspect of the present invention is an optical apparatus including the lens barrel according to any one of the first to fifth aspects.

  According to the present invention, the optical axis adjustment work can be facilitated.

FIG. 1 is a longitudinal sectional view of a lens barrel according to an embodiment of the present invention. FIG. 2 is a view of the connecting member 126 as seen from the camera body side.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a longitudinal sectional view of a lens barrel 100 according to an embodiment of the present invention, and FIG. 2 is a view of a connecting member 126 viewed from the camera body side. In FIG. 2, the cam pin 128 is not shown.

  The lens barrel 100 includes a first lens group 114, a second lens group 124, a third lens group 134, and a fourth lens group 144. The first lens group 114, the second lens group 124, the third lens group 134, and the fourth lens group 144 include lenses 111a to 111d, lenses 121a to 121b, lenses 131a to 131b, and lenses 141a to 141b, respectively. The lenses 111a to 111d, the lenses 121a to 121b, the lenses 131a to 131b, and the lenses 141a to 141b are held by holding frames 112, 122, 132, and 142, respectively. The holding frame 122 includes a holding frame 122 a that holds the lens 121 a and a holding frame 122 b that holds the lens 121 b, and both the frames 122 a and 122 b are connected via a connecting member 126. The holding frames 122a and 122b and the connecting member 126 are formed in a cylindrical shape. The outer peripheral surfaces of the holding frames 122 a and 122 b are opposed to the inner peripheral surface of the connecting member 126.

  The holding frame 122b is held in the direction of the optical axis L by the holding member 210.

  The lens barrel 100 includes a fixed barrel 140 fixed to an optical device such as a camera body, and a cam barrel 150 accommodated in the fixed barrel 140. The fixed cylinder 140 and the cam cylinder 150 are both cylindrical bodies having the optical axis L as the central axis. The cam cylinder 150 is rotatably fitted to the inner peripheral surface of the fixed cylinder 140. In the cam barrel 150, the first lens group 114, the second lens group 124, the third lens group 134, the fourth lens group 144, and the holding frames 112, 122, 132, 142 are accommodated.

  The holding frames 112, 122, and 142 are respectively coupled to cylindrical connection members 116, 126, and 146 that are fitted to the inner peripheral surface of the cam cylinder 150 so as to be rotatable around the optical axis L. The holding frame 132 is directly fitted to the inner peripheral surface of the cam cylinder 150 so as to be rotatable around the optical axis L.

  Cam pins 118, 128, 148, and 138 are coupled to the outer peripheral surfaces of the connecting members 116, 126, and 146 and the holding frame 132, respectively. On the other hand, the cam cylinder 150 is formed with a plurality of cam grooves 151 to 154 into which the cam pins 118, 128, 148, and 138 are inserted, and the cam cylinder 118 rotates around the optical axis L, whereby the cam pin 118 is rotated. 128, 148, and 138 are pushed in the optical axis L direction, and the connecting members 116, 126, and 146 and the holding frame 132 move in the optical axis L direction.

  On the inner peripheral surface of the connecting member 126, a body portion 126c that fixes the holding frame 122b in a direction along the optical axis L is provided.

  A focus ring 170 is disposed on the outer peripheral surface side of the second lens group 124. A first outer fixed barrel 200 and a zoom ring 180 are disposed on the outer peripheral surface side of the fourth lens group 144. The focus ring 170 is mounted on the outer peripheral surface of the fixed barrel 140 so as to be rotatable around the optical axis L, and is fitted to the first outer fixed barrel 200 in the optical axis L direction. The zoom ring 180 is fitted in the optical axis L direction with the first outer fixed cylinder 200 and the second outer fixed cylinder 201 so as to be rotatable around the optical axis L.

  Here, in the second lens group 124, the lens 121b held by the holding frame 122b is an alignment lens capable of adjusting the position of the optical axis L. On the outer peripheral surface of the holding frame 122b, a plurality of adjustment screws (pressing members) 190 that can be advanced or retracted in a direction orthogonal to the optical axis L, and a plurality of fixing screws that can be similarly advanced or retracted in the radial direction of the lens 121. (Fixing member) 192 is in contact. The adjustment screw 190 and the fixing screw 192 are almost opposed to each other with the optical axis L interposed therebetween.

  A first inclined surface 190a and a second inclined surface 192a (see FIG. 2) extending in a direction intersecting with the optical axis L are in contact with the adjustment screw 190 and the fixing screw 192 (see FIG. 2) on the outer peripheral surface of the holding frame 122b. 2) are formed. The inclination directions of the first inclined surface 190a and the second inclined surface 192a and the optical axis L intersect on the camera body side of the holding frame 122b.

  In addition, an elastic member (elastic body) 208 such as a coil spring that urges the holding frame 122b in a direction orthogonal to the optical axis L is disposed on the outer peripheral surface of the holding frame 122b.

  Tool access holes 157, 147, and 177 are formed in the cam cylinder 150, the fixed cylinder 140, and the focus ring 170. The tool access holes 157, 147, 177 are positioned on a virtual straight line that is orthogonal to the optical axis L of the lens 121b and passes through the adjustment screw 190 and the fixing screw 192.

  A tool such as a wrench that turns the adjusting screw 190 and the fixing screw 192 is inserted into the tool access holes 157, 147, and 177. A rubber ring 160 that closes the tool access holes 157, 147, and 177 is detachably attached to the focus ring 170.

  The cylindrical connecting member 126 is formed with two screw holes 196 extending in the radial direction of the lens 121b and two screw holes 198 (not shown) extending in the radial direction. An adjustment screw 190 is screwed into the screw hole 196, and a fixing screw 192 is screwed into the screw hole 198. The two screw holes 196 are arranged around the optical axis L with an interval of approximately 90 °. The two screw holes 198 are arranged around the optical axis L with an interval of about 90 °. One of the two screw holes 196 and one of the two screw holes 198 are opposed to each other with the optical axis L in between. The other of the two screw holes 196 and the other of the two screw holes 198 are opposed to each other with the optical axis L interposed therebetween.

  In addition, two concave portions 202 are formed on the outer peripheral surface of the holding frame 122b. The concave portion 202 is positioned near the position where the fixing screw 192 contacts the holding frame 122b.

  Each of the recesses 202 accommodates an elastic member 208. The two elastic members 208 are respectively disposed at positions substantially opposed to the two adjustment screws 190 with the optical axis L in between. The holding frame 122 b is pressed against the tip of the adjustment screw 190 by the urging force of the elastic member 208 in a direction (radial direction) orthogonal to the optical axis L. Therefore, the radial position of the holding frame 122b can be adjusted by the two adjusting screws 190 and the two elastic members 208.

  Note that only one elastic member 208 may be provided. At that time, since the holding frame 122b does not move independently in the X and Y directions, it is necessary to adjust the position of the holding frame 122b using the two adjusting screws 190.

  Next, a method for adjusting the optical axis of the lens barrel 100 having the above configuration will be described.

  The optical axis adjustment is performed by rotating a wrench inserted in the tool access holes 157, 147, 177. By screwing the adjusting screw 190 with a wrench, the holding frame 122b moves in the direction of the elastic member 208 against the urging force of the elastic member 208. By loosening the adjustment screw 190 with a wrench, the holding frame 122b moves in the direction of the adjustment screw 190 by the urging force of the elastic member 208. At this time, since the holding frame 122b is pressed against the tip of the adjustment screw 190 by the elastic member 208, the amount by which the adjustment screw 190 advances and retreats in the radial direction of the holding frame 122b and the amount by which the holding frame 122b is displaced in the radial direction. Matches. As a result, the optical axis of the lens 121b can be easily aligned with the optical axis L.

  At this time, since the tip of the adjustment screw 190 is in contact with the first inclined surface 190a formed on the holding frame 122, the holding frame 122b is pushed in the optical axis L direction, and the holding frame 122b is prevented from falling.

  After the optical axis adjustment, the wrench inserted into the tool access holes 157, 147, 177 is rotated to screw the fixing screw 192 and press the holding frame 122b in the radial direction. At this time, since the holding frame 122b is sandwiched between the adjustment screw 190 and the fixing screw 192 that are substantially opposed to each other with the optical axis L interposed therebetween, the strength against an impact applied to the lens barrel 100 is increased. As a result, the positional deviation of the adjusted optical axis L is suppressed, and the holding frame 122b can be held at a predetermined position.

  Further, since the tip of the fixing screw 192 abuts on the second inclined surface 192a of the holding frame 122b, and the pressing force can be applied to the holding frame 122b in the direction orthogonal to the optical axis L and in the optical axis L direction. Is firmly held, and it is possible to more reliably prevent the lens from falling due to dropping, vibration, impact, or the like.

  The second inclined surface 192a is not necessarily required and may be omitted. Further, when the adjustment screw 190 and the fixing screw 192 are rotated, the connecting member 126 does not rotate in the circumferential direction.

  According to this embodiment, the holding frame 122b can be urged in the radial direction and the holding frame 122b can be urged in the optical axis L direction, so that the optical axis adjustment can be performed without increasing the number of components. Work can be facilitated. Further, since the holding frame 122b is urged in the direction of the optical axis L by moving the adjusting screw 190 in the radial direction, it is not necessary to add a part for urging the holding frame 122b to the body portion 126c of the connecting portion 126. In both cases, the backlash of the holding frame 122b in the optical axis direction can be suppressed. Further, the holding frame 122b can be firmly held by the fixing screw 192, and the lens collapse due to dropping, vibration, impact, or the like can be more reliably prevented. In addition, a tool such as a wrench that turns the adjusting screw 190 and the fixing screw 192 can be inserted into the tool access holes 157, 147, and 177, and the optical axis L can be adjusted in the final process of lens assembly, thereby reducing the readjustment process. It is.

  100: lens barrel, 121b: lens (optical system), 122b: holding frame, 126: connecting member (cylinder member), 190: adjustment screw (pressing member), 190a: first inclined surface, 192: fixing screw (fixing) Member), 192a: second inclined surface, 208: elastic member (elastic body), L: optical axis.

Claims (6)

A holding frame for holding the optical system;
An elastic body provided outside the holding frame;
A pressing member that presses the holding frame toward the elastic body,
The lens barrel, wherein the holding frame includes a first inclined surface that is pressed by the pressing member and extends in a direction intersecting the optical axis.   A surface of the holding frame that has a fixing member that presses the holding frame in a direction different from the pressing direction of the pressing member, and fixes the holding frame between the pressing member and the pressing member presses the holding frame. The lens barrel according to claim 1, wherein the lens barrel is a second inclined surface extending in a direction intersecting the optical axis.   The lens barrel according to claim 2, wherein the first inclined surface and the second inclined surface have the same direction intersecting the optical axis.   A cylindrical member provided opposite to the outer periphery of the holding frame and having a barrel portion on the inner periphery for fixing the holding frame in a direction along the optical axis, and the first inclined surface of the holding frame is The lens barrel according to any one of claims 1 to 3, wherein the lens barrel is formed such that a direction opposite to the body portion intersects the optical axis.   The press member can be advanced or retracted along a direction orthogonal to the optical axis of the optical system, and the position of the holding frame is adjusted by the advance or retract of the press member. The lens barrel according to any one of 1 to 4.   An optical apparatus including the lens barrel according to any one of claims 1 to 5.

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