Patent ID: 9557522
Date: 2017-01-31
CPC Classifications: G02B

Claim:
1. A lens barrel configured to expand and contract between a collapsed state in which an optical path is shortest and a photographing state in which the optical path is longer than in the collapsed state, comprising: a first barrel configured to rotate around an optical axis by an actuator; and a second barrel configured to support the first barrel to slide freely around the optical axis and to move in an optical axis direction, wherein one of the first barrel and the second barrel is provided with a cam follower, and a cam groove with which the cam follower is configured to engage to slide freely is formed in the other, wherein, in an event the first barrel rotates around the optical axis, the cam follower is configured to slide in the cam groove and to allow the first barrel to move in the optical axis direction in relation to the second barrel, wherein the cam groove includes a first sliding portion and a second sliding portion which are both inclined in relation to the optical axis, and an inclination angle of the first sliding portion in relation to the optical axis is smaller than an inclination angle of the second sliding portion in relation to the optical axis, wherein, in an event of transitioning from the collapsed state to the photographing state, the cam follower is configured to slide on the first sliding portion and the first barrel is configured to extend in relation to the second barrel, wherein, in an event of transitioning from the photographing state to the collapsed state, the cam follower is configured to slide on the second sliding portion and the first barrel is configured to be incorporated in the second barrel, wherein a photographing state forming portion configured to be extended in a direction orthogonal to the optical axis and with which the cam follower is configured to be engaged in the photographing state, is formed in the cam groove, wherein an intersection with the first sliding portion is formed in a middle portion of the photographing state forming portion, and wherein an intersection with the second sliding portion is formed on an end portion of the photographing state forming portion.