| 摘要 |
PROBLEM TO BE SOLVED: To correct the quantity of movement of a lens up to a focusing position while moving a movable lens and puts the lens in focus without movement between front focus and rear focus. SOLUTION: An image pickup part 91 is made to pick up an image of a subject between 1st time and 2nd time during the movement of the movable lens 53 at an equal speed, and then a defocusing quantity D and a new lens driving quantity PX for eliminating the defocusing are found from PX=Ki .D. Here, a smaller coefficient between coefficients K1 and K2 corresponding to the extension positions of the movable lens at the 1st time and 2nd time is used. Further, the quantity of movement of the lens in the time needed to calculate the new lens driving quantity PX is subtracted from the above new lens driving quantity to obtain a new lens driving quantity PZ. |
