Patent ID: 8879165
Filing Date: 2014-11-04
Classification: G02B

Abstract:
1. A device for changing operating force of a lens device, comprising: an operating ring rotatably provided around an outer periphery of a lens barrel; a rotating body connected to the operating ring to rotate around a rotary shaft in a predetermined direction together with rotation of the operating ring, the rotating body having a cylindrical peripheral surface centering on the rotary shaft; a non-rotating body whose rotation is restricted, the non-rotating body having a cylindrical peripheral surface being arranged by having a gap at a position facing the peripheral surface of the rotating body in a noncontact manner; viscous fluid having viscosity interposed in the gap, the viscous fluid applying a load caused by viscosity resistance thereof against rotation of the rotating body rotating together with the operating ring to produce operating force required to rotate the operating ring by the load; an operation member for changing operating force to be operated by an operator to change the operating force; and a non-rotating body driving device for changing a value of a load against rotation of the rotating body by moving the non-rotating body in a direction of the rotary shaft corresponding to an operation of the operation member for changing operating force by an operator to change a size of an area of a sliding contact region in which the peripheral surface of the rotating body and the peripheral surface of the non-rotating body face each other.