| 摘要 |
PURPOSE:To reduce the space, and to simplify the structure by providing a means for driving a focus adjusting device in accordance with a movement of a driving part, fixing it at a focused position, and also, maintaining its fixed state irrespective of a movement of an aperture blade, and a means for releasing the fixed state. CONSTITUTION:A fixed diaphragm cam 6 and a freely rotatable diaphragm rotor 7 are placed in the rear running along an optical axis of a focusing lens 1, a tooth form 7a is formed in the periphery of the diaphragm rotor 7, and a driving force is transferred through a gear 8. The diaphragm can 6 and the diaphragm rotor 7 have light passing hole parts 6a, 6b in the respective center parts, and between the diaphragm 6 and the diaphragm rotor 7, plural pieces of aperture blades 9 are interposed, a dowel 9a which has been projected forward from each aperture blade 9 is fitted into a cam groove 6b of the diaphragm cam 6, and a dowel 9b which is projected backward is fitted into a hole part 7c of the rotor 7. As for the diaphragm rotor 7, a lever 10 being parallel to the optical axis direction is fixed, and the lever 10 transfers a driving force to a focusing cam 3 through a pin 3c only in the prescribed rotating direction centering around the optical axis, and also, releases a detained state of a detaining claw 4. In such a way, the device goes to small in size, and also, the space can be reduced, and the structure is simplified. |
