| 摘要 |
PURPOSE:To exhibit the performance of an automatic focusing device sufficiently even in strobe photography, by shifting plural stop positions of a photographic lens to a short-distance side during flash photography. CONSTITUTION:The positioning lever 5 of a lens barrel 1 has three step parts 5a, 5b, and 5c and faces a lever 12 which is so provided that it is attracted by an electromagnet 11 on a base plate 6. A lever 8 is moved to right as shown in a figure during flash photography. When the photodetection level of an automatic control circuit is low, the electromagnet 11 is powered on to attract the lever 12 and the step part 5b is locked to stop the lens barrel 1 at a 3m long- distance point. When the photodetection level is high, the electromagnet 11 is powered off and the step part 5c is locked to stop the lens barrel 1 at a 1.5m short-distance point. Then, a 5m and a 2m stop position for natural light are shifted to 3m and 1.5m during flash photography to exhibit the performance of automatic focusing sufficiently. |
