| 摘要 |
PURPOSE:To make a camera compact by, when photographing with the focal distance of an optical system in the combination of the main lens and sublenses, focusing in such a manner that the movement is inhibited in the direction of an optical axis but only the main lens and a shutter are moved. CONSTITUTION:A shutter unit is fixed to a male helicoid 1 by the use of a shutter base plate 7. A rear-lens holder 6 is provided with a set of rear lenses 39 consisting of plural lenses, and can be inserted in and retracted from a photographic optical axis. In a condition where the holder is retracted, the photographic optical system having a short focal distance is composed of only the front lens 38; in the condition where the holder is inserted, the photographic optical system having a long focal distance is composed of the front lens 38 and the rear lenses 39. During focusing for tele-photographing, only the front lens 38 and the shutter base plate 7 are integrally moved forward, and the rear lens holder 6 is held in the fixed position in relation to the camera main body 13. Therefore, when photographing with the focal distance of either wide or tele is carried out, focusing can be effected by controlling the forward movement of the main lens (front lens) 38 only. |
