Lens system with variable objective for cameras - consists of groups of divergent and convergent lenses, varying of objective focal length is achieved by varying distances between groups

摘要

The system consists of groups of lenses arranged in the following way. Beginning at the object end of the system, the system consists of a first convergent lens group and a second divergent lens group. The focal length of the variable objective is varied by varying the distance between the first and second groups. The first lens group, beginning at the object end, consists of a divergent sub-group and a convergent sub-group. The divergent sub-group, beginning at the object end, consists of a first divergent lens element which, has a smaller radius of curvature on the side which faces towards the object and to the second convergent lens element, than that on the convex surface which faces towards the image plane. USE/ADVANTAGE - For a compact camera. The distance between the end lens and the image plane is reduced.