Patent ID: 7934878

Claim:
A diaphragm driving device for a camera comprising a camera body and an interchangeable lens which is detachably attached to said camera body, wherein said interchangeable lens comprises a diaphragm mechanism having an in-lens spring device for performing a stop-down operation, said in-lens-spring device having a spring constant, wherein said camera body comprises: a diaphragm drive mechanism having a diaphragm drive motor and an in-body spring device, both of which are for making said diaphragm mechanism of said interchangeable lens perform said stop-down operation; and a controller for controlling a driving current which is supplied to said diaphragm drive motor in accordance with said spring constant of said in-lens spring device, wherein said interchangeable lens comprises a memory in which data on said spring constant of said in-lens spring device is stored, and wherein said controller reads said data on said spring constant of said in-lens spring device from said memory to control said driving current.