| 摘要 |
PURPOSE:To substantially extend the range of automatic adjustment to a focus with a great amount of deformation, by providing a manual adjusting mechanism an automatic focus adjusting mechanism. CONSTITUTION:A driving motor 14f for an automatic focus adjusting mechanism makes focus adjustment to a sliding film surface under a lens, by lifting up and down a projetion lens barrel 12 with rack and pinions 13a, 13b via a worm 13e, worm gear 13d and friction clutch 13c. On the other hand, a manual adjusting knob 16 is provided to a shaft of the pinion 13b. If the amount of deformation of focus of a sliding film to be adjusted is too large and out of the range of automatic focus adjustment, since the lens can be moved up and down independently of the motor 14f under the presence of a clutch 13 by adjusting the knob 16 manually, the position of the lens can be readjusted within the operating range of the automatic adjusting mechanism. |
