| 摘要 |
PROBLEM TO BE SOLVED: To secure a tilt of a lens barrel or posture accuracy of a deviation in an extending state in collapsible lens barrels, and keep optical performance high.SOLUTION: A lens barrel has: a stationary barrel 1; a cam ring 2 that is supported rotatably with respect to the stationary barrel, and includes a cam section 21 provided with a first cam area and a second cam area; a straight advance barrel 3 that advances and retreats in an optical axis direction with respect to the stationary barrel by a rotation of the cam ring in the second cam area; a straight advance guide section 11 that is installed on the stationary barrel, and guides an advance/retreat in an optical axis direction of the straight advance barrel; a cam follower section 31 that is installed on the straight advance barrel, and engages with the cam section; a straight advance key section that is installed on the straight advance barrel, and engages with the straight advance guide; and urging means 25 for generating an urging force locking the stationary barrel and the straight advance barrel in the first cam area, and for not locking the stationary barrel and the straight advance barrel in the second cam area. |
