| 摘要 |
PROBLEM TO BE SOLVED: To reduce the divergence of focus all over the area from a wide angle end to a telephoto end by calculating the correction amount of a lens group for the adjusting moving loci at each magnification, and then focusing. SOLUTION: Based on each data calculated from the designed value of an ideal lens system for a lens shape or the like, a first lens group 3 and a second lens group 4 are respectively moved or fixed, so that an adjustment reference position is decided. The moving loci of the lens groups 3 and 4 are fitted to the adjustment reference position so as to decide the adjusting moving loci of the lens groups 3 and 4. A reference amount for correction at a nearly intermediate magnification between the wide angle end and a specified moving end magnification is detected. The correction amount of the lens group 3 for each magnification from the wide angle end to the telephoto end is calculated taking the reference amount of the correction as a reference, so that focusing is performed. |
