Patent ID: 7616381

Claim:
An optical system, adapted for providing an image beam, comprising: a light source, adapted for providing an illumination beam including a first illumination beam with a first polarization, and a second illumination beam with a second polarization; a beam splitting/combining device, comprising: a first PBS, reflecting the first illumination beam from the light source, and the second illumination beam from the light source passes through the first PBS; a second PBS, reflecting the second illumination beam from the first PBS; a QWP, wherein of the first illumination beam reflected by the first PBS passes through the QWP; a first reflector, reflecting the first illumination beam from the QWP, wherein the first illumination beam from the first reflector passes through the QWP, and then passes through the first PBS; a second reflector, reflecting the first illumination beam passing through first PBS, wherein the first illumination beam reflected by the second reflector is reflected by the second reflector; and a light valve, adapted for converting the first illumination beam from the second PBS into a first image beam passing through the second PBS, and converting the second illumination beam from the second PBS into a second image beam passing through the second PBS, wherein the first image beam combines with the second image beam to form the image beam.