Projection-type display apparatus having polarized beam splitters and an illuminating device

摘要

A color separating/ light guiding optics comprises two independent dichroic mirrors (6, 8), reflection mirrors (7G, 10, 10', 7R) and correcting lenses (9, 9'). A horizontal plane region (31) occupied by these optical components is entirely involved in a horizontal plane region (32) occupied by a light modulating/ color compositing/ image projecting optics. A red beam (r) is guided along a detoured optical path extending across a dead space below a projection lens (16). Although the optical path length of the red beam (r) becomes longer than those of the blue beam (b) and the green beam (g), the detoured optical path provides a sufficient space for installing the correcting lenses (9, 9'). The substantial optical path lengths of three primary color beams can be equalized with each other by the provision of these correcting lenses (9, 9').