JP5182643B2 - Lens barrel - Google Patents

Description

  The present invention relates to a lens barrel.

2. Description of the Related Art Conventionally, there is known an optical adjustment structure that performs parallel eccentric adjustment of a first group lens barrel that is integrally held with an eccentric ring by a balance of push and pull of push screws provided at three locations (see the following publication).
JP 2006-91153 A

  However, in the above adjustment, it is necessary to loosen or tighten a plurality of push screws, which is not easy to work with. There is a problem of end. Although the above problem can be solved by disposing a plurality of elastic portions respectively at positions facing the plurality of push screws, the number of parts increases and the assemblability deteriorates.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a lens barrel capable of facilitating alignment workability without increasing the number of parts.

  In order to solve the above-mentioned problems, the invention according to claim 1 is an optical system holding unit that holds an optical system, an abutting portion that comes into contact with a cylindrical member provided on an outer periphery of the optical system holding unit, and the optical system holding unit. A holding frame having an elastic portion provided between a portion and the abutting portion; and the deformation of the elastic portion causes the abutting portion to abut against the cylindrical member, so that the optical system of the holding frame And pressing means for pressing the holding portion in a direction intersecting the optical axis of the optical system.

  According to a second aspect of the present invention, in the lens barrel according to the first aspect, the pressing means is a screw that is screwed into the cylindrical member and presses the optical system holding portion of the holding frame. To do.

  According to a third aspect of the present invention, in the lens barrel according to the first or second aspect, the elastic portion has a groove.

  According to a fourth aspect of the present invention, in the lens barrel according to any one of the first to third aspects, the optical system holding portion is pressed in a direction different from a pressing direction of the optical system holding portion by the pressing means. And a first fixing means for fixing the optical system holding part between the pressing means and the pressing means.

  According to a fifth aspect of the present invention, in the lens barrel according to any one of the first to fourth aspects, the cylindrical member has a body portion that fixes the holding frame in a direction along the optical axis on the inner periphery. And a second fixing means for fixing the optical system holding portion of the holding frame to the body-attached portion.

  According to a sixth aspect of the present invention, in the lens barrel according to any one of the first to fifth aspects, when the optical system holding portion moves by the pressing means, the optical system holding portion moves in a direction other than the pressing direction. It has the movement prevention means to prevent, It is characterized by the above-mentioned.

  According to the present invention, alignment workability can be facilitated without increasing the number of parts.

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

  FIG. 1 is a conceptual diagram showing a cross section of a lens barrel according to an embodiment of the present invention, and FIG. 2 is a conceptual diagram showing a cross section taken along line II-II in FIG.

The lens barrel 100 includes a lens chamber (optical system holding portion) 14 that holds the adjustment lens group (optical system) 4 and an annular member (elastic portion) 20 that is integrally formed on the outer peripheral portion of the lens chamber 14. A lens holding member (holding frame) 10 and an adjustment screw (pressing means) 11 that is disposed in the fixed cylinder 1 at an interval of 90 ° and adjusts the position of the optical axis L of the adjustment lens group 4. Yes.
At one end of the fixed cylinder 1, a fixed lens group 2 arranged to face the adjustment lens group 4 is held. A mount 5 having a bayonet portion for fixing to an optical device such as a camera body is fixed to the other end of the fixed cylinder 1 by a screw 6.

  The plurality of adjustment screws 11 can be advanced or retracted in a direction perpendicular to the optical axis L, and the tips of the adjustment screws 11 abut on the adjustment screw receiving surface 12 on the outer peripheral surface of the annular member 20. A radial receiving portion (contact portion) 27 of the annular member 20 contacts the inner peripheral surface of the fixed cylinder 1.

  When the adjusting screw 11 is screwed, a groove 21 is formed in the annular member 20 along a peripheral edge of the annular member 20 over a predetermined length so that a part of the annular member 20 can be easily deformed. Is formed. The outer part of the part provided with the groove 21 of the annular member 20 is deformable, and the other part is formed so as not to be deformed.

  When the adjustment lens group 4 is large and heavy, a part of the annular member 20 is deformed by vibration or impact, and the contact position between the tip of the adjustment screw 11 and the adjustment screw receiving surface 12 is changed. There is a risk of moving with respect to 1. In order to prevent this, a fixing screw (first fixing means) 16 is arranged in the fixed cylinder 1. The fixing screw 16 can be moved forward or backward in a direction orthogonal to the optical axis L. By screwing the fixing screw 16 from a direction different from that of the adjusting screw 11 and pressing the inner side from the groove 21 of the annular member 20, the annular member 20 is sandwiched and fixed by the fixing screw 16 and the adjusting screw 11. The position where the fixing screw 16 is screwed is, for example, the position indicated by the one-dot chain line in FIG.

  Further, a thrust stop screw (second fixing means) 25 that is screwed into an annular adjustment group base (body portion) 7 fixed in the fixed cylinder 1 with a screw 3 and can be advanced or retracted in the direction of the optical axis L. Thus, the annular member 20 is fixed to one end surface of the adjustment group base 7. The thrust stop screw 25 is screwed into the screw hole 17 of the adjustment group base portion 7 through four thrust stop screw holes 22 formed in the annular member 20. The four thrust stop screw holes 22 are arranged around the optical axis L at predetermined intervals.

  A wave washer 8 is sandwiched between the thrust stop screw 25 and one end surface (surface on the rear side in the optical axis direction) of the annular member 20. The wave washer 8 comes into contact with a wave washer receiving surface 23 formed around the thrust stop screw hole 22.

  Further, a steel ball 9 is sandwiched between the adjustment group base 7 and the other end surface (the front surface in the optical axis direction) of the annular member 20. The steel ball 9 is fitted in a circular recess 24 formed on the other end surface of the annular member 20. Circular recesses 24 are formed on the other end surface of the annular member 20 at three locations around the optical axis L at predetermined intervals. The movement of the lens holding member 10 was smoothed by sandwiching the steel ball 9 between the adjustment group base 7 and the other end surface of the annular member 20.

  Further, the other end surface of the annular member 20 is formed with a rotation boss (movement preventing means) 26 that engages with a recess (not shown) formed in the adjustment group base 7. Depending on the position of the adjusting screw receiving surface 12 and the radial receiving portion 27 of the annular member 20, a force for rotating the annular member 20 is generated when pressed by the adjusting screw 11, but the rotation boss 26 can prevent the rotation. .

  Next, alignment work between the fixed lens group 2 and the adjustment lens group 4 will be described.

  The alignment is performed in the order of, for example, a point light source (not shown), a fixed lens group 2, an adjustment lens group 4 and a measurement unit (not shown) having an image sensor, and the optical axes o. a. Done by placing on top.

  The alignment is performed by deforming a part of the annular member 20 with the adjusting screw 11 and pressing the lens chamber 14 in a direction intersecting the optical axis L to thereby adjust the optical axis o. a. Is performed by moving the optical axis L of the adjustment lens group 4 with reference to.

  For example, the amount of eccentricity (the amount of deviation between the optical axis L of the adjustment lens group 4 and the optical axis oa of the fixed lens group 2) is calculated based on the position of the point image formed on the image sensor, The adjustment screw 11 is screwed on the basis of the measurement result obtained by the measurement unit, and the optical axis L of the adjustment lens group 4 is changed to the optical axis o. a. To match.

  After the alignment, the fixing member 16 is tightened to fix the annular member 20 between the adjustment screw 11 and the fixing screw 16, and the movement of the annular member 20 is prevented.

  According to this embodiment, alignment workability can be facilitated without increasing the number of parts.

  A washer may be used instead of the wave washer 8. Further, when the lens holding member 10 can be moved smoothly, the steel ball 9 may be omitted. Furthermore, the adjustment group base 7 may be formed integrally with the fixed cylinder 1 and the adjustment group base 7 may be omitted.

  Further, the annular member 20 may be formed integrally with the lens chamber 14 and the annular member 20 may be omitted.

  Further, by changing the width between the one end face side and the other end face side of the groove 21 and changing the degree of deformation between the one end face side and the other end face side when pressed by the adjusting screw 11, the inner portion of the groove 21 is always It can also be configured to be pressed against the adjustment group base 7.

FIG. 1 is a conceptual diagram showing a cross section of a lens barrel according to an embodiment of the present invention. FIG. 2 is a conceptual diagram showing a cross section taken along line II-II in FIG.

Explanation of symbols

  1: fixed cylinder (cylinder member), 4: adjustment lens group (optical system), 7: adjustment group base (body part), 10: lens holding member (holding frame), 11: adjustment screw (pressing means), 14 : Lens chamber (optical system holding part), 16: fixing screw (first fixing means), 20: annular member (elastic part), 21: groove, 25: thrust stop screw (second fixing means), 26 : Rotation stop boss (movement preventing means), 27: radial receiving part (contact part), L: optical axis.

Claims (6)

An optical system holding part that holds an optical system, a contact part that comes into contact with a cylindrical member provided on an outer periphery of the optical system holding part, and an elasticity provided between the optical system holding part and the contact part A holding frame having a portion;
Pressing means for pressing the optical system holding portion of the holding frame in a direction intersecting the optical axis of the optical system by bringing the contact portion into contact with the cylindrical member by deformation of the elastic portion; A lens barrel characterized by having   The lens barrel according to claim 1, wherein the pressing means is a screw that is screwed into the cylindrical member and presses the optical system holding portion of the holding frame.   The lens barrel according to claim 1, wherein the elastic portion has a groove.   A first fixing unit configured to press the optical system holding unit in a direction different from a pressing direction of the optical system holding unit by the pressing unit and to fix the optical system holding unit between the pressing unit and the optical system holding unit; The lens barrel according to any one of claims 1 to 3, wherein:   The cylindrical member has a barrel portion for fixing the holding frame in a direction along the optical axis on an inner periphery, and second fixing means for fixing the optical system holding portion of the holding frame to the barrel portion. The lens barrel according to claim 1, wherein the lens barrel is provided.   The lens according to claim 1, further comprising a movement preventing unit that prevents the optical system holding unit from moving in a direction other than the pressing direction when the optical system holding unit is moved by the pressing unit. A lens barrel.

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