Illumination optical system and projector comprising the same

摘要

Brightness of optical equipment can be adjusted as required. An illuminating optical system is comprised a light source, a lens array (320) including a plurality of lenses for splitting light emitted from the light source into a plurality of partial beams and a polarization conversion element array (360) for aligning the polarization directions. The illuminating optical system is further comprised a light shielding member (350) between the lens array (320) and polarization conversion element array (360) to adjust the quantity of incident light on polarization splitter films provided in the polarization conversion element array (360).