Illumination optical system and image display apparatus including the same

摘要

An illumination optical system including a diffraction device and an image display apparatus including the illumination optical system are provided. The illumination optical system includes a light source emitting light; and a light separation/integration device including a diffraction device on at least one incident side, the diffraction device diffracting the light to decrease an incident angle to a predetermined range. The image display apparatus includes the illumination optical system; an image optical system, which modulates light incident from the illumination optical system to form an image; and a projection optical system, which projects light reflected from the image optical system onto a screen.