Copying apparatus having a high-speed copying optical system

摘要

A copying apparatus having an optical system comprising a fixed original carriage, a rotatable mirror for scanning the original carriage and an image forming optical system for imaging a light flux from the rotatable mirror on a photosensitive medium, said image forming optical system being provided with a swing and tilting lens system having a swing and tilting function and a light path length correcting lens system including at least two movable lens groups movable along the direction of the optic axis and having the function of correcting the length of the light path while maintaining a predetermined image forming magnification, said swing and tilting lens system and said movable lens groups being moved in synchronism with said rotatable mirror to thereby form the image of the original on the photosensitive medium without swing and tilting.