| 摘要 |
<p>PROBLEM TO BE SOLVED: To shorten focusing time and to improve the responsiveness of an electronic shutter by setting a focusing lens in an initial state at a middle point between the longest distance and the shortest distance to a subject and shortening the distance of the lens for extending in the case of detecting that a power source is turned on. SOLUTION: In the case of detecting that the power source is turned on or that a shutter is driven, the focusing lens is set in the initial state at the middle point between the longest distance and the shortest distance to the subject so as to shorten the distance of the lens for extending. Relating the driving device, a focusing ring 13 is meshed with a lens holder 15 and rotatably supported between a shutter base 30 and a motor base 10. When the shutter starts actions or when the power source is turned off in an electronic circuit part and then it is changed to an on-state, the position of the ring 13 is detected, and the ring 13 is adjusted to an initial position when the ring 13 is not positioned at the set initial position.</p> |
