IMAGING OPTICAL SYSTEM, OPTICAL SYSTEM, OPTICAL DEVICE, IMAGING UNIT, IMAGE READER, AND PROJECTION TYPE IMAGE DISPLAY DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a compact imaging optical system having high optical performance wherein a catoptric unit and a dioptric unit are appropriately positioned and arranged. SOLUTION: The imaging optical system is provided with the dioptric unit L having positive optical power as a whole and the catoptric unit l including at least three or more reflecting surfaces with curvature in this order from a magnifying side. The system is provided with a pupil arranged on the magnifying side further from the reflecting surface on the furthest magnifying side in the catoptric unit. Further, 0.2T2 are satisfied. In the expression, fL and fR denote the focal distance of the dioptric unit and the focal distance of the catoptric unit, T1 denotes the smallest distance between reflection surfaces, and T2 denotes a distance from a pupil position to the farthest refractive surface. COPYRIGHT: (C)2005,JPO&NCIPI