| 摘要 |
<P>PROBLEM TO BE SOLVED: To allow a cam cylinder to be held with a cover cylinder with few backlashes, to decrease eccentricity, inclination and displacement to the cover cylinder. <P>SOLUTION: When a first cam cylinder 5 rotates, by cam action between first, second, and third cam portions 5a, 5b, and 5c and cam followers 1a, 2a, and 3a, first, second and third lens units 1, 2, and 3 move in a direction of an optical axis C1. The first cam cylinder 5 includes a taper groove portion 5d on an outer peripheral surface thereof, in a peripheral direction. A cam follower 7a is integrally formed on an inner peripheral surface of the cover cylinder 7 arranged on the outer peripheral side of the first cam cylinder 5. The cam follower 7a includes a tapered surface corresponding to a tapered surface of the taper groove portion 5d. The taper groove portion 5d engages with the cam follower 7a so that the cover cylinder 7 holds the first cam cylinder 5 rotatably around the optical axis C1. <P>COPYRIGHT: (C)2013,JPO&INPIT |
