| 摘要 |
PURPOSE:To move a focusing lens correctly to the in-focus position by rotating a rotating member by a certain quantity for a minute deviation extent of the image-forming position. CONSTITUTION:A deviation extent DELTAL of an object image from a predeterminate image-forming surface is detected by a focus detecting means, and the rotation of a rotating member 19 driven by a driving means which outputs a driving force corresponding to the signal for transmission of this deviation extent DELTAL is transmitted to a focusing lens F. In this case, the driving force is transmitted by a cam means 19a which has such lead that DELTAtheta=C.DELTAL (C is a constant ) is true between a minute rotation quantity DELTAtheta of the rotating member 19 and the minute deviation extent DELTAL of the image-forming position. |
