ILLUMINATING OPTICAL SYSTEM AND LIQUID CRYSTAL PROJECTOR DEVICE USING THE OPTICAL SYSTEM

摘要

PROBLEM TO BE SOLVED: To efficiently obtain a uniform illumination effect in an illuminating optical system and a liquid crystal projector device using the optical system by improving picture quality so as not to generate a shadow of a joined ridgeline of a cross dichroic prism by two lens arrays constituted of arranging column-like convex lens arrays of which pitches are mutually shifted and properly arranging a polarization transforming optical system. SOLUTION: The vertical angle ridgeline 71 of four prisms forming a cross dichroic prism 70 is arranged so as to intersect with an optical axis at right angles, the polarization transforming optical system 3 is arranged so that a plane including the ridgeline 71 and the optical axis is rectangular to the extending direction of stripes of aλ/2 phase film 32 and the lens string shifting direction of plural column-like convex lens arrays constituting 1st and 2nd lens arrays 21, 22 is rectangular to the plane.