| 摘要 |
<p>PROBLEM TO BE SOLVED: To make a variable power operation in a photographing region silent.SOLUTION: A collapsible lens device storing a photographing optical system forming the optical image of an object and having a variable power function includes a DC motor 100, a driven cam ring 600 rotationally driven by the DC motor, to achieve the displacement between a collapsed state and an extended state and achieve the variable power function, and a gear train transmitting the driving force of the DC motor to the driven cam ring. The gear ratio of the final stage of the gear train in the photographing region from the wide-angle end to the telephoto end of the photographing optical system is smaller than the gear ratio of the gear train in the collapsed state.</p> |
