Patent ID: 6491450
Filing Date: 2002-12-10
Classification: G03B

Abstract:
A shutter for a camera comprising: sectors for opening and closing a shutter opening by reciprocal pivotal movement; a motor for reciprocally and pivotally moving the sectors by forwardly and reversely rotating a rotor of the motor by applying current to a coil of the motor in forward and reverse directions; a memory circuit for storing electricity conduction data used for applying current to the coil corresponding to operational characteristics of the motor and the sectors; and a control circuit for controlling the application of electricity to the coil in accordance with a brightness of an object to be photographed and executing exposure control in accordance with the brightness of the object; wherein the electricity conduction data is set to comprise data for driving the sectors in a given direction and brake pulse data for exerting a force to the sectors in a direction opposite the given direction to prevent a rebounding motion of the sectors, and the control circuit applies forward and reverse driving pulses to the motor to effect opening and closing of the sectors to perform an exposure by applying the forward driving pulse to open the shutter sectors and thereafter applying a reverse braking pulse followed by alternately applying forward and reverse pulses to prevent rebounding of the shutter sectors after completion of a shutter opening operation, and by applying the reverse driving pulse to close the shutter sectors and thereafter applying a forward braking pulse followed by alternately applying reverse and forward pulses to prevent rebounding of the shutter sectors after completion of a shutter closing operation.