JP2010008920A - Lens position adjustment structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens position adjustment structure able to easily and highly precisely adjust the decentration of a lens without a large jig. <P>SOLUTION: The lens position adjustment structure includes: a lens hold frame holding the lens; an outer frame having an optically axial position regulating face, which positions the lens hold frame in the direction of the optical axis and supports the lens hold frame so as to be movable within a plane intersecting the optical axis at right angles; an elastic hold member, which is engaged with the outer frame, elastically presses the lens hold frame so as to be close to the optically axial position regulating face, thereby holding the lens hold frame in a fixed position relative to the outer frame; and two oblong holes formed in the lens hold frame, which are located within the same plane intersecting the optical axis at right angles and disposed such that the lengthwise directions of these oblong holes are substantially intersecting at right angles within the same plane intersecting the optical axis at right angles. A position adjusting means inserted in the two oblong holes applies moving force perpendicular to the lengthwise directions of each oblong hole, and thereby the position of the lens hold frame held by the elastic hold member is adjusted within the plane intersecting the optical axis at right angles. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a structure for adjusting an optical axis position of a lens.

In the process of assembling the lens barrel, it is generally performed to adjust the eccentricity of the optical axis by moving a specific lens among a plurality of lenses constituting the photographing optical system within a plane orthogonal to the optical axis. (For example, Patent Document 1 and Patent Document 2).
JP 2002-333564 A Japanese Patent Application Laid-Open No. 2007-289853

  Adjustment of the eccentricity of the lens at the time of conventional assembly was performed by setting it on an adjustment jig. However, since the jig was large and heavy, there was a problem that workability was poor and the lens was burdened. It was. In addition, due to the structure of the jig, the adjustment work was conventionally performed with the lens optical axis facing the vertical direction. However, in the actual use state of the lens barrel, it is within a certain range based on the horizontal direction. In many cases, the optical axis is oriented, and it has been desired to be able to adjust the eccentricity in a form close to the actual usage.

  The present invention has been made in view of the above problems, and provides a lens position adjustment structure that can easily and accurately adjust the eccentricity of a lens without using a large jig. Objective.

  The lens position adjusting structure of the present invention includes a lens holding frame that holds a lens; an optical axis direction position regulating surface that determines a position in the optical axis direction of the lens holding frame, and the lens holding frame is within a plane orthogonal to the optical axis. An outer frame that is movably supported; an elastic holding member that is engaged with the outer frame and elastically presses the lens holding frame in the approaching direction to the optical axis position restricting surface to hold the lens holding frame at a fixed position with respect to the outer frame; and A position that is formed in the lens holding frame and is located in the same plane orthogonal to the optical axis and has two elongated holes whose longitudinal directions are substantially orthogonal to each other in the plane orthogonal to the optical axis; A moving force in a direction orthogonal to the longitudinal direction of each elongated hole is given by the adjusting means, and the position of the lens holding frame held by the elastic holding member is adjusted in the plane orthogonal to the optical axis.

  The elastic holding member is preferably made of a bayonet ring. Specifically, the lens holding frame has a cylindrical portion that holds the outer peripheral portion of the lens, and an annular flange that protrudes from the cylindrical portion in the outer diameter direction, and the outer frame is the lens holding frame. An annular flange portion surrounding the annular flange portion. The bayonet ring is located opposite to the annular flange portion of the outer frame, and contacts the annular flange portion of the lens holding frame so as to be elastically deformable in the optical axis direction, and the outer side from the opposite side of the annular portion. It is set as the shape which has the nail | claw part engaged with the cyclic | annular flange part of a frame.

  The position adjusting means includes a slot fitting portion that fits into the slot with a diameter corresponding to the width of each slot formed in the lens holding frame, and a rotation center shaft that is eccentric with respect to the center of the slot fitting portion. It is preferable to comprise by the eccentric shaft member which has a part. In this case, on the annular flange portion of the outer frame, two shaft holes for supporting the rotation center shaft portion of the eccentric shaft member are formed, and the lens holding frame further protrudes in the outer diameter direction from the annular flange portion, It is preferable to provide two radial protrusions positioned opposite to the two axial holes, and form a long hole through each of the two radial protrusions in the optical axis direction.

  More specifically, the two radially projecting portions of the lens holding frame can be moved in the projecting radial direction from the annular collar, and the movement is restricted in the direction orthogonal to the projecting radial direction and supported by the outer frame. 1 radial protrusion, and a second radial protrusion supported so as to be movable in both a radial direction protruding from the annular flange and a direction orthogonal to the protruding radial direction, A long hole formed in the second radial protrusion by forming a long hole formed in the radial protrusion with the longitudinal direction oriented in a direction perpendicular to the protruding radial direction of the first radial protrusion. The lens holding frame can be adjusted in position in the plane orthogonal to the optical axis described above by forming the lens in the longitudinal direction parallel to the protruding radial direction of the second radial protruding portion.

  Two elongated holes in the lens holding frame are provided at substantially the same radial position as the annular portion of the bayonet ring, and an opening that exposes the two elongated holes is formed in the bayonet ring, thereby achieving radial compactness. be able to.

  In the present invention, the mode of positioning the lens holding frame with respect to the optical axis direction position restricting surface of the outer frame is arbitrary. For example, a lens other than the lens held by the lens holding frame is positioned in the optical axis direction position of the outer frame. By contacting the other lens and the lens held by the lens holding frame with each other at the lens contact surface orthogonal to the optical axis, the lens whose eccentricity is adjusted can be made with high accuracy. Can be supported.

  According to the present invention described above, the lens holding frame is moved in the plane orthogonal to the optical axis by operating the two long holes on the lens holding frame while the lens holding frame is held by the elastic holding member. Does not require a jig. In addition, the holding force of the elastic holding member enables the lens holding frame position adjustment work in a mode in accordance with the actual use state in which the optical axis of the lens is oriented horizontally or close to it. Therefore, the eccentricity adjustment of the lens can be performed easily and with high accuracy.

  A schematic structure of a zoom lens barrel 70 having a lens position adjusting structure according to the present invention will be described with reference to FIGS. The imaging optical system of the zoom lens barrel 70 includes, in order from the object (subject) side, a first lens group LG1, a second lens group LG2, a shutter blade S that also serves as an aperture, a third lens group LG3, a low-pass filter 25, and an imaging element. In the following description, the optical axis direction means a direction parallel to the optical axis O of the photographing optical system.

  The low-pass filter 25 and the image sensor 71 are unitized and fixed to the image sensor holder 23, and the image sensor holder 23 is fixed to the rear portion of the housing 22. A zoom motor 150 and an AF motor 160 are supported outside the housing 22.

  The third group lens frame 51 that holds the third lens group LG3 is supported so as to be movable in the optical axis direction with respect to the housing 22, and is driven by the AF motor 160.

  A cam ring 11 is supported inside the housing 22. The cam ring 11 is rotated by the driving force of the zoom motor 150 and moves in the optical axis direction while rotating from the lens barrel storage state (FIG. 3) to the photographing state (FIG. 4). In the zoom range (between the wide end in the upper half of FIG. 4 and the tele end in the lower half of FIG. 4), it is rotated at a fixed position in the optical axis direction.

  The first feed cylinder 13 and the straight guide ring 10 are supported with the cam ring 11 in between. The first feeding cylinder 13 and the rectilinear guide ring 10 are each guided in a straight line with respect to the housing 22 in the optical axis direction, and can be relatively rotated with respect to the cam ring 11 and move together in the optical axis direction. Are combined.

  The rectilinear guide ring 10 guides the second group lens moving frame 8 so that it can move relative to the optical axis. Inside the second group lens moving frame 8, a second group lens holding frame 2 that holds the second lens group LG2 and a shutter block 100 that holds the shutter blades S are supported. Further, the first feeding cylinder 13 guided linearly in the optical axis direction with respect to the housing 22 further guides the second feeding cylinder 12 so as to be relatively movable in the optical axis direction. A first lens group LG <b> 1 is supported inside the second feeding cylinder 12 via a first group lens holding frame 1.

  The second feeding cylinder 12 has a first group cam follower CF1 protruding in the inner diameter direction, and the first group cam follower CF1 is slidably fitted in a first group control cam groove CG1 formed on the outer peripheral surface of the cam ring 11. is doing. Since the second feeding cylinder 12 is guided linearly in the direction of the optical axis via the first feeding cylinder 13, when the cam ring 11 rotates, the second feeding cylinder 12, i.e., the first feeding cylinder 12, according to the shape of the first group control cam groove CG1. The lens group LG1 moves along a predetermined locus in the optical axis direction.

  The second group cam follower CF2 provided on the outer peripheral surface of the second group lens moving frame 8 is engaged with the second group control cam groove CG2 formed on the inner peripheral surface of the cam ring 11. Since the second group lens moving frame 8 is linearly guided in the optical axis direction via the straight guide ring 10, when the cam ring 11 rotates, the second group lens moving frame 8, i.e., the first group moving cam frame CG2, is rotated. The two lens group LG2 moves along a predetermined locus in the optical axis direction.

  A group biasing spring 27 made of a compression spring is inserted between the second group lens moving frame 8 and the second feeding cylinder 12, and the second group lens moving frame 8 and the second feeding cylinder 12 are separated from each other. Is being energized.

  The zoom lens barrel 70 having the above structure operates as follows. In the lens barrel storage state shown in FIGS. 1 and 3, the length of the optical system in the optical axis direction compared to the imaging state shown in FIGS. 2 and 4 (imaging of the image sensor 71 from the object side surface of the first lens group LG1). The distance to the surface is short. When a transition signal to the photographing state in this lens barrel storage state (for example, a main switch provided in a camera on which the zoom lens barrel 70 is mounted) is input, the zoom motor 150 is driven in the lens barrel feeding direction. The cam ring 11 is fed forward in the optical axis direction while rotating. The rectilinear guide ring 10 and the first feed cylinder 13 move forward together with the cam ring 11. When the cam ring 11 rotates, on the inner side, the second group lens moving frame 8 guided linearly through the straight guide ring 10 is predetermined in the optical axis direction due to the relationship between the second group cam follower CF2 and the second group control cam groove CG2. It is moved by the trajectory. Further, when the cam ring 11 rotates, the second feeding cylinder 12 guided linearly through the first feeding cylinder 13 on the outside of the cam ring 11 is related to the first group cam follower CF1 and the first group control cam groove CG1. Is moved along a predetermined locus in the optical axis direction.

  That is, the first lens group LG1 and the second lens group LG2 are fed out from the lens barrel retracted state by the former moving amount of the cam ring 11 with respect to the housing 22 and the second feeding cylinder 12 with respect to the cam ring 11, respectively. The latter is determined as the sum of the amount of forward movement of the cam ring 11 relative to the housing 22 and the amount of cam extension of the second group lens moving frame 8 relative to the cam ring 11. Zooming is performed by moving the first lens group LG1 and the second lens group LG2 along the photographing optical axis O while changing the air interval between them. When the lens barrel is extended from the housed state, first, the wide end extended state shown in the upper half section of FIG. 4 is obtained. When the zoom motor 150 is further driven in the lens barrel extending direction, the telephoto section shown in the lower half section of FIG. The end is extended. In the zoom region between the tele end and the wide end, the cam ring 11 rotates at the above-mentioned fixed position and does not advance or retreat in the optical axis direction. When a storage state transition signal (for example, turning off the main switch of the camera) is input, the zoom motor 150 is driven in the lens barrel storage direction, and the zoom lens barrel 70 is retracted in the opposite manner to the above-described extension operation. I do.

  Further, a barrier blade 104 capable of opening and closing the front of the first lens group LG1 is provided at the front end portion of the second feeding cylinder 12, and the barrier blade 104 is closed when the lens barrel is housed, so that the shooting state is restored. The barrier blade 104 is opened according to the feeding operation.

  The third lens group frame 51 that supports the third lens group LG3 is moved back and forth in the optical axis direction by the AF motor 160 independently of the driving of the first lens group LG1 and the second lens group LG2 by the zoom motor 150 described above. Can be made. When the optical system is in the zoom range from the wide end to the tele end, the third lens group LG3 is moved in the optical axis direction by driving the AF motor 160 according to the subject distance information obtained by the distance measuring means. Move to perform focusing.

  The details of the holding structure for the first lens group LG1 will be described with reference to FIG. As shown in FIG. 5, the first lens group LG1 includes a front lens LG1-1 and a rear lens LG1-2, a first group lens holding frame 1 (lens holding frame), and a second feeding cylinder 12. Is held between the first lens group outer frame portion 12a (outer frame) formed in the vicinity of the front end portion.

  As shown in FIGS. 9 and 10, the first group lens outer frame portion 12a of the second feeding cylinder 12 has a plurality of flange-shaped portions with different positions in the optical axis direction, and has the largest front flange. The step 12b is located at the forefront in the optical axis direction, the intermediate flange step 12c having an intermediate diameter is located behind the front flange step 12b, and is located at the deepest position behind the optical axis. A small-diameter rear flange step 12d is provided. Each of the flange step portions 12b, 12c, and 12d has an optical axis orthogonal plane M1, M2, M3 that is substantially orthogonal to the photographing optical axis O facing forward. In FIG. 9, hatching is added to make it easy to identify the optical axis orthogonal planes M1, M2, and M3. The intermediate flange portion 12c and the rear flange step portion 12d are connected by an intermediate cylindrical portion 12e having a cylindrical shape centered on the photographing optical axis O, and the intermediate cylindrical portion 12e and the rear flange step portion 12d. Between them, a cylindrical inner surface 12f having a diameter smaller than the inner diameter of the intermediate cylindrical portion 12e is formed, and a part of the cylindrical inner surface 12f is cut away to form a bonding recess 12g. Although one adhesive recess 12g is visible in FIG. 9, a plurality of adhesive recesses 12g are provided at different circumferential positions. Further, an optical path opening 12h penetrating in the optical axis direction is formed in the inner edge portion of the rear flange step portion 12d.

  The first group lens holding frame 1 is made of synthetic resin, and as shown in FIGS. 6 and 7, the lens holding cylinder part 1a centering on the photographing optical axis O and the lens holding cylinder part 1a project in the outer diameter direction. An annular flange 1b, and a front retaining portion 1c that is located at the front end of the lens holding cylinder 1a and protrudes in the inner diameter direction. The inner peripheral surface of the lens holding cylinder 1a is a cylindrical inner surface 1d with the photographing optical axis O as the center, and a plurality of press-fitting convex portions 1e are formed on the cylindrical inner surface 1d at different circumferential positions. ing. Each press-fitting convex portion 1e has a gently convex arcuate surface shape, and the rear end portion in the optical axis direction becomes a gentle slope 1f that gradually approaches the cylindrical inner surface 1d as it advances rearward. ing.

  The annular flange 1b is provided with a first projecting piece (first radial projecting part) 1g and a second projecting piece (second radial projecting part) 1h at symmetrical positions across the photographing optical axis O. Protrusively in the radial direction. A first elongated hole 1i is formed in the first protruding piece 1g, and a second elongated hole 1j is formed in the second protruding piece 1h. As shown in FIGS. 12 and 14, the second elongated hole 1j has a longitudinal direction substantially equal to the protruding radial direction of the second protruding piece 1h from the annular flange 1b (radiating direction centered on the photographing optical axis O). Match) and parallel. On the other hand, as shown in FIGS. 12 and 13, the first elongated hole 1i is in the protruding radial direction of the first protruding piece 1g from the annular flange 1b (substantially coincides with the radial direction centered on the photographing optical axis O). The longitudinal direction is oriented in a direction substantially perpendicular to the direction. That is, the first long hole 1 i and the second long hole 1 j are arranged in a relationship in which the longitudinal directions thereof are orthogonal to each other in a plane orthogonal to the photographing optical axis O. Further, both the first long hole 1i and the second long hole 1j penetrate the projecting pieces 1g and 1h in the optical axis direction.

  The front flange step portion 12b is cut out in the first group lens outer frame portion 12a of the second feeding cylinder 12, and the two cutout portions 12i into which the two projecting pieces 1g and 1h of the first group lens holding frame 1 can enter. -N, 12i-W are formed. The two notches 12i-N and 12i-W have different widths in the circumferential direction. As shown in FIG. 13, the first notches 12i-N are narrower than the notches 12i-N narrow in the circumferential direction. The projecting piece 1g is movable in the projecting radial direction (radiating direction centering on the photographing optical axis O) and is engaged with its movement restricted in a direction orthogonal to the projecting radial direction. Further, as shown in FIG. 14, with respect to the notch 12i-W that is wide in the circumferential direction, the second projecting piece 1h has a projecting radial direction (radiating direction centered on the photographing optical axis O), and the A predetermined amount of movement is allowed and engaged in any direction perpendicular to the protruding radial direction. A pair of eccentric pin support holes 12j are formed on the optical axis orthogonal plane M2 of the intermediate flange stepped portion 12c facing the notches 12i-N and 12i-W. The pair of pin support holes 12j are provided at substantially symmetrical radial positions across the photographing optical axis O.

  The front lens LG1-1 has a convex surface on the object side and a concave surface on the image surface side, and an annular rear contact surface (optical axis direction position restricting surface) K1 centering on the photographing optical axis O is formed near the outer edge of the concave surface. Is formed. The rear lens LG1-2 has a convex surface on the object side and a concave surface on the image surface side, and an annular front contact surface K2 centering on the photographing optical axis O is formed in the vicinity of the outer edge portion of the convex surface, and in the vicinity of the outer edge portion of the concave surface Similarly, an annular rear contact surface K3 is formed. The rear abutment surface K1, the front abutment surface K2, and the rear abutment surface K3 are all planes that are substantially orthogonal to the photographing optical axis O.

  The outer diameter of the front lens LG1-1 is substantially the same as the inner diameter of the cylindrical inner surface 1d of the first group lens holding frame 1, and the outer diameter of the rear lens LG1-2 is the outer diameter of the cylindrical inner surface 12f of the first group lens outer frame portion 12a. It is approximately the same diameter as the inner diameter. Further, the outer diameter of the lens holding cylinder portion 1a of the first group lens holding frame 1 is smaller than the inner diameter of the intermediate cylindrical portion 12e of the first group lens outer frame portion 12a. On the other hand, the annular flange 1b of the first group lens holding frame 1 has a larger diameter than the intermediate cylindrical portion 12e.

  The first lens group LG1 is assembled as follows. First, the front lens LG1-1 is held by the first group lens holding frame 1. The front lens LG1-1 is inserted into the lens holding cylinder portion 1a from the rear end side opposite to the front retaining portion 1c with respect to the first group lens holding frame 1. As described above, the cylindrical inner surface 1d of the lens holding cylinder portion 1a is substantially the same as the outer diameter of the front lens LG1-1, and the press-fitting convex portion 1e is formed on the cylindrical inner surface 1d. As a result, the outer peripheral surface of the front lens LG1-1 presses the press-fitting convex portion 1e and pushes the lens holding tube portion 1a in the diameter-enlarging direction, so that the front side of the first group lens holding frame 1 made of synthetic resin The lens LG1-1 is press-fitted. When the front lens LG1-1 is press-fitted, the gentle slope 1f is first brought into contact with the press-fitting convex portion 1e, so that the front lens LG1-1 can be smoothly inserted without being caught with the press-fitting convex portion 1e. Since the front lens LG1-1, which is a glass lens, has a higher hardness than the first-group lens holding frame 1 made of synthetic resin, the front lens LG1-1 is not deformed by this press-fitting operation. The insertion of the front lens LG1-1 into the first group lens holding frame 1 is completed when it comes into contact with the front retaining portion 1c. The front lens LG1-1 is held with a holding force by press fitting, and is not bonded and fixed to the first group lens holding frame 1.

  Further, the rear lens LG1-2 is assembled to the first group lens outer frame portion 12a of the second feeding cylinder 12. As shown in FIG. 10, the rear lens LG1-2 is inserted into the first group lens outer frame portion 12a with the rear abutting surface K3 facing rearward in the optical axis direction, and the rear abutting surface K3 is an optical axis orthogonal plane. (Optical axis direction position regulating surface) The insertion is regulated by applying to M3, and the optical axis direction position with respect to the first group lens outer frame portion 12a is determined. As described above, in the state where the outer diameter size of the rear lens LG1-2 is substantially equal to the inner diameter of the cylindrical inner surface 12f and the rear contact surface K3 is applied to the optical axis orthogonal plane M3, the rear lens is placed on the cylindrical inner surface 12f. The outer peripheral surface of LG1-2 abuts, and the radial position of the rear lens LG1-2 is also fixed. Then, as shown in FIG. 10, by injecting the adhesive B1 between the bonding concave portion 12g and the outer peripheral surface of the rear lens LG1-2, the rear lens LG1-2 becomes the first group lens outer frame portion 12a. Fixed to.

  Subsequently, the combined body of the first group lens holding frame 1 and the front lens LG1-1 is assembled to the first group lens outer frame portion 12a to which the rear lens LG1-2 is already attached. At the time of this assembly, the first projecting piece 1g and the second projecting piece 1h of the first group lens holding frame 1 and the two notches 12i-N and 12i-W of the first group lens outer frame part 12a have the same rotational direction phase. The protrusions 1g and 1h are caused to enter the corresponding notches 12i-N and 12i-W. As a result, the first long hole 1i and the second long hole 1j are respectively positioned in front of the pin support hole 12j (see FIGS. 11 to 14).

  The first group lens holding frame 1 has an outer diameter size that allows the lens holding cylinder portion 1a excluding the annular flange 1b to be inserted into the intermediate cylindrical portion 12e of the first group lens outer frame portion 12a, as shown in FIG. The lens holding cylinder portion 1a is inserted into the intermediate cylindrical portion 12e with the rear abutting surface K1 of the front lens LG1-1 facing rearward. This insertion is restricted by the rear abutting surface K1 of the front lens LG1-1 abutting against the front abutting surface K2 of the rear lens LG1-2. In this insertion restricted state, as shown in FIG. 10, there is an optical axis direction gap P1 between the annular flange 1b of the first group lens holding frame 1 and the optical axis orthogonal plane M2 of the intermediate flange step 12c. That is, the first group lens holding frame 1 is not directly involved in the positioning of the front lens LG1-1 in the optical axis direction, and the position of the front lens LG1-1 in the optical axis direction is determined via the rear lens LG1-2. It is determined by the optical axis orthogonal plane M3 of the feeding cylinder 12. In other words, not the first group lens holding frame 1 that is deformed by press-fitting but the second feeding cylinder 12 that is a separate member from the first group lens holding frame 1 is the position restriction surface of the front lens LG1-1 in the optical axis direction. The optical axis orthogonal plane M3 is provided.

  Further, as shown in FIG. 10, the lens holding of the first group lens holding frame 1 in a state where the rear abutting surface K1 of the front lens LG1-1 is in contact with the front abutting surface K2 of the rear lens LG1-2. There is a radial clearance P2 between the cylindrical portion 1a and the intermediate cylindrical portion 12e of the first group lens outer frame portion 12a, and the eccentric adjustment of the front lens LG1-1 is performed within the range of the radial clearance P2. Can do.

  During the alignment operation of the front lens LG1-1, it is temporarily held by the bayonet ring (elastic holding member) 3 with respect to the first group lens outer frame portion 12a. As shown in FIG. 8, the bayonet ring 3 includes an annular outer diameter side bridging portion 3a extending in the circumferential direction, four retaining claws 3b formed in the middle of the outer diameter side bridging portion 3a, and an outer diameter. Four elastic arm portions 3c formed away from the side bridge portion 3a toward the inner diameter side, two inner diameter side recesses 3d formed at substantially symmetrical radial positions across the photographing optical axis O, and each elastic arm It has four adhesive injection holes 3e formed in the vicinity of the base end of the portion 3c. The pair of inner diameter side recesses 3d are located on the circumferential extension of the outer diameter side bridging portion 3a and the elastic arm portion 3c. The retaining claws 3b are offset rearward in the optical axis direction with respect to the optical axis orthogonal plane where the outer diameter side bridging portion 3a is located. The elastic arm portion 3c is a cantilever extending portion having one end connected to the outer diameter side bridging portion 3a and the other end being a free end, and is elastically deformed in the optical axis direction. In a free state, it is curved backward in the optical axis direction with respect to the optical axis orthogonal plane where the outer diameter side bridging portion 3a is located.

  As shown in FIGS. 9 and 12, the first lens group outer frame portion 12a has a claw introduction hole 12k that passes through the front flange step portion 12b, and communicates with the claw introduction hole 12k, and behind the front flange step portion 12b. Four nail storage holes 12m are formed at different positions in the circumferential direction. The four claw introducing holes 12k are formed at circumferential intervals corresponding to the four retaining claws 3b of the bayonet ring 3, and all the retaining claws 3b are placed in the claw introducing holes 12k in a specific rotational phase. Can enter. When the bayonet ring 3 is rotated after the retaining claws 3b have entered, as shown in FIGS. 10 and 11, the respective retaining claws 3b move into the claw receiving holes 12m, and are moved to the front flange step portion 12b. On the other hand, the bayonet ring 3 is prevented from coming forward. In this retaining state, the outer diameter side bridging portion 3a of the bayonet ring 3 is positioned to face the optical axis orthogonal plane M1 of the front flange step portion 12b. Further, the elastic arm portion 3c is brought into contact with the annular flange 1b of the first group lens holding frame 1 and elastically deformed forward in the optical axis direction, and with respect to the first group lens holding frame 1 by a force to restore from the elastic deformation. Applying an urging force to the rear in the optical axis direction. By this urging force, the rear abutting surface K1 of the front lens LG1-1 is pressed against the front abutting surface K2 of the rear lens LG1-2, and the combined body of the first group lens holding frame 1 and the front lens LG1-1 is obtained. Temporarily held with respect to the first group lens outer frame portion 12a. The front lens LG1-1 in the temporary holding state is moved in the radial direction along the rear abutting surface K1 and the front abutting surface K2, which are planes orthogonal to the photographing optical axis O, by applying a predetermined force. Can do. As can be seen from FIG. 11, in the state in which the bayonet ring 3 is attached, two parts of the bayonet ring 3 including the outer diameter side bridging portion 3a and the elastic arm portion 3c and the first group lens holding frame 1 are provided. The long holes 1i and 1j are located at substantially the same radial position about the photographing optical axis O. The bayonet ring 3 is formed with an inner diameter side recess 3d as an opening that exposes the long holes 1i, 1j at the same radial position, so that the long holes 1i, 1j are attached with the bayonet ring 3 attached. It is possible to access.

  For the alignment operation of the front lens LG1-1, an eccentric pin (position adjusting means, eccentric shaft member) 14 shown in FIGS. 5 and 12 is used. The eccentric pin 14 is eccentric with respect to the small-diameter shaft portion (rotation center shaft portion) 14a having a diameter corresponding to the eccentric pin support hole (shaft hole) 12j formed in the second feeding cylinder 12 and the center with respect to the small-diameter shaft portion 14a. And the diameter of the large diameter shaft portion 14b is the width of the first long hole 1i and the second long hole 1j formed in the first group lens holding frame 1. Is almost equal. As shown in FIG. 11, with the bayonet ring 3 attached, the first long hole 1 i and the second long hole 1 j are exposed forward through a pair of inner diameter side recesses 3 d of the bayonet ring 3. Then, as shown in FIG. 12, the eccentric pin 14 is inserted into each of the elongated holes 1i, 1j and the eccentric pin support hole 12j communicating with the elongated holes 1i, 1j. The inserted eccentric pin 14 has a small-diameter shaft portion 14a pivotally supported by the eccentric pin support hole 12j, and a large-diameter shaft portion 14b abutting against the side surfaces of the long holes 1i and 1j. Here, when the eccentric pin 14 inserted into the first long hole 1i is rotated, the side surface of the first long hole 1i is pushed by the large-diameter shaft portion 14b, and the upper and lower sides of FIG. A moving force acts in the direction, that is, the protruding radial direction of each protruding piece 1g, 1h (the direction orthogonal to the longitudinal direction of the first elongated hole 1i). The first projecting piece 1g in which the first elongated hole 1i is formed can move in the projecting radial direction with respect to the notch 12i-N, and move (rotate) in a direction perpendicular to the projecting radial direction. Therefore, when a moving force is applied from the eccentric pin 14 to the first elongated hole 1i, both side surfaces of the first projecting piece 1g receive guidance from the inner surface of the notch 12i-N, The first group lens holding frame 1 is moved in the projecting radius direction of each projecting piece 1g, 1h (vertical direction in FIG. 12). On the other hand, when the eccentric pin 14 inserted into the second long hole 1j is rotated, the side surface of the second long hole 1j is pushed by the large-diameter shaft portion 14b, and the horizontal direction of FIG. A moving force in the direction (a direction perpendicular to the longitudinal direction of the second elongated hole 1j) acts. The second projecting piece 1h in which the second elongated hole 1j is formed is in any of the projecting radial direction of each projecting piece 1g, 1h and the direction orthogonal to the projecting radial direction with respect to the notch 12i-W. Since a predetermined amount of movement is allowed, when the moving force is applied from the eccentric pin 14 to the second elongated hole 1j on the second projecting piece 1h side, the first group lens holding frame 1 has a protrusion radius. Oscillating motion is performed with the other first projecting piece 1g restricted in the orthogonal direction as a fulcrum. Therefore, by rotating the two eccentric pins 14 in combination, the position of the front lens LG1-1 held by the first group lens holding frame 1 can be arbitrarily adjusted within a plane orthogonal to the photographing optical axis O.

  When the eccentric adjustment of the front lens LG1-1 is completed, the first group lens holding frame 1 is fixed to the first group lens outer frame portion 12a of the second feeding cylinder 12 with an adhesive B2, as shown in FIG. . As shown in FIGS. 9 and 12, a part of the inner diameter side of the front flange step portion 12b is formed on the first group lens outer frame portion 12a at a position adjacent to the claw introduction hole 12k in the front flange step portion 12b. Notched, four adhesive recesses 12n facing the outer periphery of the annular flange 1b of the first group lens holding frame 1 are formed. The four adhesive injection holes 3e of the bayonet ring 3 are formed at positions corresponding to the four adhesive recesses 12n, and the adhesive B2 is injected into the adhesive recess 12n through the adhesive injection holes 3e. Is done. The eccentric pin 14 is removed after the first group lens holding frame 1 is bonded and fixed.

  As described above, in the lens position adjustment structure of the present embodiment, the first group lens holding frame 1 is elastically held by the bayonet ring 3 with respect to the second feeding cylinder 12 and formed on the first group lens holding frame 1. Since the first group lens holding frame 1 is moved in the plane orthogonal to the optical axis by the rotation of the eccentric pin 14 inserted into the two long holes 1i, 1j, the deflection of the front lens LG1-1 can be easily performed without using a large jig. The lead can be adjusted, and the workability is excellent. Since the holding force by the bayonet ring 3 acts on the first group lens holding frame 1 and the force is not large, the front lens LG1-1 in the temporary holding state is not overloaded. Further, the front lens LG1-1 can be held with the photographing optical axis O oriented in the horizontal direction by the holding force of the bayonet ring 3, and the access and rotation operation of the eccentric pin 14 with respect to the two long holes 1i, 1j are also in a horizontal state. Therefore, the eccentricity adjustment can be performed under conditions close to the usage state of the zoom lens barrel 70, and the adjustment accuracy can be improved.

  The bayonet ring 3 is formed with two inner diameter side recesses 3d positioned on the circumferential extension of the outer diameter side bridging portion 3a and the elastic arm portion 3c. Since the access to the holes 1i and 1j is performed through the two inner diameter side recesses 3d, the structure has an excellent space efficiency in the radial direction.

  As mentioned above, although this invention was demonstrated based on illustration embodiment, this invention is not limited to this embodiment. For example, in the embodiment, the rear lens LG1-2 is sandwiched between the front lens LG1-1 and the optical axis orthogonal plane M3 of the second feeding cylinder 12, but the eccentricity is performed without sandwiching other lenses. A structure in which the lens to be adjusted is brought into direct contact with the outer frame (second feeding cylinder 12) may be employed.

  In the embodiment, the operations related to the eccentricity adjustment of the first lens group LG1, such as the attachment of the bayonet ring 3 and the insertion of the eccentric pin 14 into the long holes 1i, 1j, are performed by access from the front in the optical axis direction. For the foremost first lens group LG1, it is preferable to adjust the eccentricity by the work from the front in this way, but in the present invention, the direction of the bayonet ring attachment and the operation to the elongated hole is limited. For example, when the decentering adjustment is performed on the rear lens group in the photographing optical system, the adjustment operation may be performed from the rear in the optical axis direction.

It is an external appearance perspective view of the storage state of the zoom lens barrel to which the present invention is applied. It is an external appearance perspective view of the photographing state of the zoom lens barrel. It is sectional drawing of the accommodation state of the zoom lens barrel. It is sectional drawing of the imaging state of the zoom lens barrel. It is a disassembled perspective view of the holding part of a 1st lens group. It is a front perspective view of a 1st group lens holding frame. It is a back perspective view of the 1st group lens holding frame. It is a front perspective view of the bayonet ring for 1st group lens holding | maintenance. It is a front perspective view of the 1st group lens outer frame part of the 2nd feeding cylinder. It is sectional drawing which shows the holding structure of a 1st lens group. It is a front view of the 2nd delivery cylinder in the state where a bayonet ring was attached. It is a front view of the 2nd delivery cylinder in the state where a bayonet ring was removed. FIG. 13 is an enlarged view of the vicinity of a first protrusion of the first group lens holding frame in FIG. 12. FIG. 13 is an enlarged view of the vicinity of a second protrusion side of the first group lens holding frame in FIG. 12.

Explanation of symbols

1 Group 1 lens holding frame (lens holding frame)
DESCRIPTION OF SYMBOLS 1a Lens holding | maintenance cylinder part 1b Annular collar 1c Front retaining part 1d Cylindrical inner surface 1e Press-fitting convex part 1f Slow slope 1g 1st protrusion (1st radial protrusion)
1h Second protrusion (second radial protrusion)
1i 1st long hole 1j 2nd long hole 2 2 group lens holding frame 3 bayonet ring (elastic holding member)
3a Outer diameter side bridging part 3b Retaining claw 3c Elastic arm part 3d Inner diameter side concave part (opening part)
3e Adhesive injection hole 8 Second lens group moving frame 10 Straight guide ring 11 Cam ring 12 Second feed cylinder 12a First lens group outer frame (outer frame)
12b Front flange step 12c Intermediate flange step 12d Rear flange step 12e Intermediate cylindrical portion 12f Cylindrical inner surface 12g Adhesive recess 12h Optical path opening 12i-N 12i-W Notch 12j Eccentric pin support hole (shaft hole)
12k Claw introduction hole 12m Claw storage hole 12n Adhesive recess 13 First feeding cylinder 14 Eccentric pin (position adjusting means, eccentric shaft member)
14a Small diameter shaft (rotation center shaft)
14b Large diameter shaft part (long hole fitting part)
22 Housing 23 Image sensor holder 25 Low pass filter 27 Group bias spring 51 Third lens group frame 70 Zoom lens barrel 71 Image sensor 100 Shutter block 104 Barrier blade 150 Zoom motor 160 AF motor B1 B2 Adhesive CF1 Group cam follower CF2 Second group cam follower CG1 First group control cam groove CG2 Second group control cam groove K1 Rear abutment surface K2 of front lens Rear abutment surface K3 of rear lens Rear abutment surface LG1 of rear lens First lens group LG1-1 Front lens LG1-2 Rear lens LG2 Second lens group LG3 Third lens group M1 Optical axis orthogonal plane M2 of the front flange step portion Optical axis orthogonal plane M3 of the intermediate flange step Optical axis orthogonal plane of the rear flange step portion (outside (The optical axis position restriction surface of the frame)
O Optical axis P1 of photographing optical system Optical axis direction gap P2 Radial direction gap S Shutter blade

Claims (6)

A lens holding frame for holding the lens;
An outer frame having an optical axis direction position regulating surface for determining a position in the optical axis direction of the lens holding frame, and movably supporting the lens holding frame in a plane orthogonal to the optical axis;
An elastic holding member that is engaged with the outer frame and elastically presses the lens holding frame in the approaching direction to the position restriction surface in the optical axis direction and holds the lens holding frame at a fixed position with respect to the outer frame; and formed on the lens holding frame, Two elongated holes that are located in the same plane orthogonal to the optical axis and whose longitudinal directions are substantially orthogonal to each other in the plane orthogonal to the optical axis;
With
A moving force in a direction perpendicular to the longitudinal direction of each of the elongated holes is given by the position adjusting means inserted into the two elongated holes, and the lens holding frame held by the elastic holding member is within the optical axis orthogonal plane. A lens position adjustment structure characterized by adjusting the position. The lens position adjustment structure according to claim 1, wherein the lens holding frame includes a cylindrical portion that holds an outer peripheral portion of the lens, and an annular flange that protrudes from the cylindrical portion in the outer diameter direction.
The outer frame has an annular flange portion that forms an annular shape surrounding the annular flange portion of the lens holding frame,
The elastic holding member includes an annular portion facing the annular flange portion of the outer frame and in contact with the annular flange portion of the lens holding frame so as to be elastically deformable in the optical axis direction, and the outer frame from the opposite side of the annular portion. A lens position adjusting structure comprising a bayonet ring having a claw portion engaged with the annular flange portion. 3. The lens position adjusting structure according to claim 2, wherein the position adjusting means has an elongated hole fitting portion that fits into the elongated hole with a diameter corresponding to a width of each elongated hole, and a center of the elongated hole fitting portion. And an eccentric shaft member having an eccentric rotation center shaft portion,
The outer frame has, on the annular flange portion, two shaft holes that support the rotation center shaft portion of the eccentric shaft member,
The lens holding frame has two radial protrusions that protrude in an outer radial direction from the annular flange portion in a symmetric positional relationship with respect to the optical axis of the lens, and that are opposed to the two shaft holes, A lens position adjusting structure in which the elongated hole penetrating in the optical axis direction is formed in each of two radial protrusions. 4. The lens position adjusting structure according to claim 3, wherein the two radial projecting portions of the lens holding frame are movable in a projecting radial direction from the annular flange with respect to the outer frame, A first radial projecting portion that is supported while being restricted in the orthogonal direction, and a first projecting portion that is supported so as to be movable in both the projecting radial direction from the annular flange and the direction orthogonal to the projecting radial direction. 2 radial protrusions,
The oblong hole formed in the first radial protrusion is formed with the longitudinal direction facing the direction perpendicular to the protrusion radial direction of the first radial protrusion, and is formed in the second radial protrusion. The lens position adjusting structure is formed such that the elongated hole is formed with its longitudinal direction parallel to the protruding radial direction of the second radial protruding portion. 5. The lens position adjusting structure according to claim 2, wherein the two elongated holes of the lens holding frame are at substantially the same radial position as the annular portion of the bayonet ring, A lens position adjusting structure having an opening for exposing two elongated holes. 6. The lens position adjusting structure according to claim 1, wherein a lens different from the lens held by the lens holding frame abuts on the optical axis direction position restricting surface of the outer frame. A lens position adjustment structure in which a lens holding frame determines a position in the optical axis direction of the lens holding frame by contacting the lens and the lens held by the lens holding frame with each other at a lens contact surface orthogonal to the optical axis.

Images