Patent ID: 8783886

Claim:
An illumination system for use in a projection device, comprising: a first light source for emitting a first light beam; a second light source for emitting a second light beam; an optical device defining a main optical axis and focusing the first light beam and the second light beam on a first focal point and a second focal point respectively, wherein the first focal point and the second focal point are disposed on two opposite sides of the main optical axis respectively; a wavelength transformer disposed at the second focal point and transforming the second light beam into a third light beam; and a first dichroic mirror disposed between the first light source, the second light source and the optical device, wherein the first light beam and the second light beam are allowed to travel through the first dichroic mirror, and the third light beam is reflected by the first dichroic mirror; wherein the third light beam is emitted from the second focal point, sequentially through the optical device, and is then reflected to the optical device by the first dichroic mirror to be focused on the first focal point.