Zoom lens system with three or more lens groups and a procedure for its alignment that allows mid-length focal length adjustments to be made precisely as well as short and long focal length adjustments

摘要

Zoom lens system with at least three lens groups with focal length changed by altering the distance between two or more lens groups. Three alignment mechanisms (T1-T3) can be used to move first, second or third lens group during assembly and alignment processes. Independent claims are made for procedures for alignment of a multiple lens group zoom assembly.