| 摘要 |
<P>PROBLEM TO BE SOLVED: To achieve cam driving without looseness by allowing a lateral surface of a cam follower to constantly contact a lateral surface of a cam groove, and to achieve not only simplification of a configuration but also reduction in the number of manufacturing steps by eliminating the need of biasing means or the like. <P>SOLUTION: A lens barrel comprises a first frame body 10 and a second frame body 20 which can move relatively to the first frame body. The lens barrel also includes a cam groove 12 formed on the inner surface of the first frame body and a cam follower 22 formed on the outer surface of the second frame body and movably engaged with the cam groove. The cam groove comprises a plurality of areas whose lateral surfaces have different inclined angles, and has a first area with which the cam follower is engaged in a zoom operation changing the optical magnification of a subject image. The first area is composed of a first partial area substantially parallel to the circumferential direction of the first frame body and a second partial area having a prescribed inclined angle to the circumferential direction of the first frame body. The cam follower has a plurality of lateral surfaces which differ in the inclined angles. <P>COPYRIGHT: (C)2012,JPO&INPIT |
