| 摘要 |
PROBLEM TO BE SOLVED: To highly accurately correct the deviation of an image-forming position caused by an environmental change by driving and controlling a movable lens group by a lens driving means when an automatic focusing function is stopped. SOLUTION: A controlling means 7 obtains the driving amount of a fourth lens group(RR) 104 which is the movable lens group based on a focusing signal from an automatic focusing means 16 and outputs a driving control signal to a driver 11. Then, the driver 11 drives the lens driving means 9 based on the driving control signal from the controlling means 7 and moves the RR 104 in the direction of an optical axis, so that the automatic focusing of the lens group RR 104 is performed. When the operation (function) of the automatic focusing means 16 is stopped (OFF) by an automatic focusing controlling means 17, the environmental temperature of an optical system 1 is detected by a detecting means 12 and is stored, and in the case that the environmental temperature is changed thereafter, the fluctuation of the image-forming plane position of the optical system 1 caused by the change of the environmental temperature is corrected by moving the RR 104 to a focusing position by using the function of the automatic focusing means 16. |
