JP2005266472A5

JP2005266472A5 -

Info

Publication number: JP2005266472A5
Application number: JP2004080460A
Authority: JP
Filing date: 2004-03-19
Publication date: 2010-03-25
Anticipated expiration: 2024-03-19

Claims

A fixed cylinder;
A photographic optical system comprising a plurality of lens groups;
A zoom operation member that changes the relative positional relationship of the variable power lens group in the imaging optical system by a rotation operation, and changes the imaging magnification of the imaging optical system;
A cam ring that has a positioning cam groove portion that performs positioning at the time of zooming operation of the zooming focusing lens unit that also serves as a focusing operation among the zooming lens unit; ,
A guide groove for positioning in the optical axis direction while rotating the zooming focusing lens group around the optical axis together with the positioning cam groove during the zooming operation, and around the cam ring and the optical axis during the zooming operation; A relatively rotating guide ring;
A guide member having a cam pin portion that engages with the positioning cam groove portion and the guide groove and positions the zoom lens unit;
It has a focusing cam groove for engaging with the cam pin and changing the position of the variable magnification focusing lens group in the optical axis direction to perform a focusing operation, and moves integrally with the variable magnification focusing lens group A focus group moving frame to be
A focus operation member that regulates rotation around the optical axis of the focus group moving frame during the zooming operation, and performs focusing by rotating the focus group moving frame around the optical axis during the focusing operation;
A lens barrel.

A fixed cylinder;
A zoom operation member that is rotated during zoom operation;
A first cam ring provided on the inner peripheral side of the fixed cylinder;
A first sliding frame provided to be fitted to the inner peripheral side of the first cam ring and having a movement amount in the direction along the optical axis equal to that of the first cam ring;
A cam pin portion provided so as to move integrally with the first sliding frame;
A second sliding frame provided on the inner peripheral side of the first cam ring;
A third sliding frame provided on the outer peripheral side of the fixed cylinder;
A first cam groove portion provided on the third sliding frame and fitted with the cam pin portion;
A second cam ring provided on the outer peripheral side of the third sliding frame and provided so that the amount of rotation is equal to that of the first cam ring during zoom operation;
A second cam groove portion provided in the second cam ring and into which the cam pin portion is fitted;
A focus group moving frame provided on the inner peripheral side of the third sliding frame;
A third cam groove portion provided in the focus group moving frame and fitted with the cam pin portion;
With
When the zoom operation is performed, the first cam groove and the second cam ring are different from each other so that the rotation amount of the first cam ring and the second cam ring is different from the rotation amount of the first sliding frame and the cam pin portion. A cam shape of the cam groove portion and the third cam groove portion is formed,
A lens barrel characterized by

The lens barrel according to claim 2,
The amount of rotation of the first sliding frame and the cam pin portion is:
Less than the amount of rotation of the first cam ring and the second cam ring;
A lens barrel characterized by

In the lens barrel according to claim 2 or 3,
A spring member that applies a relative spring biasing force to the first sliding frame and the first cam ring;
A lens barrel characterized by

In the lens barrel according to any one of claims 2 to 4,
The first sliding frame and the second sliding frame are provided to be fitted to the inner peripheral surface of the same inner diameter of the first cam ring;
A lens barrel characterized by