Patent ID: 8132918

Claim:
An illumination apparatus comprising: a light source device adapted to emit light having an asymmetric intensity distribution; and a polarization conversion element adapted to align polarization states of the light emitted from the light source device, wherein the polarization conversion element includes, a splitting section adapted to split incident light input from the light source device into transmitted light and reflected light having the polarization states different from each other in a direction in which an intensity distribution of the incident light is asymmetric, and a conversion section adapted to convert the polarization state of one of the transmitted light and the reflected light into the polarization state of the other of the transmitted light and the reflected light, a mirror system adapted to emit the other light and the one light, which is converted by the conversion section, from the polarization conversion element in substantially the same direction is configured to include the splitting section, and the mirror system is disposed so that the direction, in which the intensity distribution of the one light emitted from the polarization conversion element is asymmetric, is reversed with respect to a direction, in which the intensity distribution of the other light emitted from the polarization conversion element is asymmetric.