Patent ID: 8964306
Filing Date: 2015-02-24
Classification: G02B

Abstract:
1. A lens barrel comprising: an outer barrel which is supported to be movable linearly in an optical axis direction of an imaging optical system, said outer barrel including a first cam follower; an internal movable member which is supported to be movable linearly in said optical axis direction in said outer barrel, said internal movable member including a second cam follower; a biaser which biases said internal movable member forward in said optical axis direction; a limit portion which determines a limit of forward movement of said internal movable member in said outer barrel; a rotational cam ring; a first cam groove which is formed on a peripheral surface of said cam ring and engaged with said first cam follower to control movement of said outer barrel in said optical axis direction in accordance with a rotation of said cam ring; and a second cam groove which is formed on said peripheral surface of said cam ring, on which said first cam groove is formed, so as to be open at a front end of said cam ring, wherein, when said outer barrel is positioned in front of a predetermined position in said optical axis direction, said second cam follower is disengaged forwardly from said second cam groove so that said internal movable member is positioned at a forward-movement limit in said outer barrel that is determined by said limit portion, and wherein, when said outer barrel moves rearward beyond said predetermined position in said optical axis direction in accordance with rotation of said cam ring, said second cam groove is engaged with said second cam follower and moves said internal movable member rearward in said optical axis direction in said outer barrel against a biasing force of said biaser.