Optical axis correcting system

摘要

An optical axis correcting system includes a first afocal optical system, an optical deflector which corrects the deviation of an optical axis of light incident upon the first optical system, a second afocal optical system, and a light convergent optical system. The optical axis correcting system satisfies (1) 3.60<|fp(I)/fN(I)|<5.30, (2) 1.00<|fp(II)/fN(II)|<2.41, and (3) 0.12 <r1 (II)/f<0.23, wherein fp(I) represents the focal length of a positive lens group of the first optical system, fN(I) represents the focal length of a single negative lens element of the first optical system, fp(II) represents the focal length of a positive lens group of the second optical system, fN(II) represents the focal length of a negative lens group of the second optical system, r1(II) represents the radius of curvature of the surface oif a positive lens element of the second afocal optical system closest to the optical deflector, and f represents the focal length of the whole optical system.