| 摘要 |
PURPOSE:To reduce the weight and size of a device and to permit light winding by providing prescribed transparent optical members in such a way that said members can be put into and from the optical axis behind a main photographing lens as desired and adjusting the focus thereby fixing the photographing lens. CONSTITUTION:Plural transparent optical members 3-5 are held in a holder 2 and are kept energized by a spring 6 so as to cross an optical axis L. A detaining mechanism consisting of a stop lever 8 and a magnet 7 is provided. The members 3-5 are constituted of members of glass, etc. having the same refractive index and different thickness. The holder 2 is moved downward by a winding operation and after the holder is detained by a detaining lever 11, the holder 2 is disengaged by the AF signal of a range finder 10 and the magnet is de- energized, then, for example, the member 3 is inserted into the optical axis and the object at the point P2 is formed on the film plane. The focus is thus adjusted without moving the main lens, by which the weight and size of the device are reduced and the light winding is made possible. |
