| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a light-amount controlling device that drives a shutter blade and a light-amount adjusting member by a single drive source and can reduce oscillation of a drive unit occurring when the shutter blade stops at a location without a stopper.SOLUTION: A light-amount controlling device comprises: a drive unit; a base plate that has an aperture part formed; a shutter blade that is movable between a close state closing the aperture part and an open state opening the aperture part; a light-amount adjusting blade that is movable between an advancing state advancing to the aperture part and a retreating state retreating from the aperture part; a transmission mechanism that can transmit driving force of the drive unit to the shutter blade and the light-amount adjusting blade; detection means that can detect counter-electromotive force of the drive unit; and control means that can control a drive of the drive unit. In first and third drive areas of the transmission mechanism, the shutter blade is configured to implement an open/close operation, and in a second drive area of the transmission mechanism, the light-amount adjusting blade is configured to implement an advancement/retreat operation. The control means is configured to control the drive of the drive unit on the basis of an output of the detection means when the shutter blade moves from the close state to the open state.</p> |
