Polarization converting device, illumination optical system and projector

Abstract

Provided are a polarization converting device capable of downsizing parts and improving light-use efficiency, and an illumination optical system capable of obtaining illuminating light with high efficiency and superior illumination characteristics by using the polarization converting device, and a projector. A polarization splitting film is inclined at approximately 45° upward and downward with respect to an optical axis, thereby the polarization splitting film is formed in the shape of the letter V of which the apex is pointed to a direction where incident light enters. A reflective surface has such a shape that the polarization splitting film is horizontally flipped, thereby it is formed in the shape of the letter V of which the apex is pointed to a direction where a polarized component is emitted. A plurality of pairs of the polarization splitting film with the shape of the letter V and the reflective surface with the shape of the letter V in which their apexes are pointed to different directions are disposed in parallel. In this case, the polarization splitting film and the reflective surface are disposed so as not to overlay each other in a thickness direction (an optical axis direction).