VARIABLE FOCAL LENS CONTROLLER

摘要

PURPOSE:To simplify a mechanical part for driving a variable power lens group by finding out a correction value of an image forming position deviation at the time of stopping a variable power driving means and driving a variable power driving means. CONSTITUTION:A variable power control part 16 starts a variable power motor MZ in a power up direction on the basis of a variable power direction information from a driving direction deciding part 15 and a starting signal STR and then stops the motor MZ at a prescribed point. A maximum delivering distance computing part 9 calculates a maximum delivering distance Fpx on the basis of the output of a focal distance detector 8. A proportional constant computing part 10 receives an output from a focusing lens group position detector 7 and calculates a proportional constant Cfp. A focusing correction computing part 11 receives the delivering distance Fpx and the constant Cfp and calculates a proposed focusing position Se. A focus control part 12 controls the focus motor MF so as to drive focusing lens groups 2a, 2b. Since the lens 2b is fixed on a variable power transmission cell so as not to be changed by variable power operation in said constitution, the variable power lens driving mechanism can be simplified.