摘要 |
A light recovery apparatus for a projection display comprises a reflector (702) having a first (704) and a second (706) focal points; a source (708) of electro-magnetic radiation disposed proximate to said (704) focal point of said reflector (702) to emit rays of radiation that reflect from said reflector (702) and converge substantially at said second (706) focal point; a retro-reflector (712) disposed opposite said reflector (702) to reflect at least a portion of the electromagnetic radiation that does not impinge directly on said reflector (702) toward said reflector (702) through the (704) focal point of said reflector (702) to increase the flux intensity of the converging rays; a light pipe (416) having an input surface and an output surface, said input surface of said light pipe (416) disposed proximate to said second (706) focal point to collect and transmit substantially all of said radiation; and polarization beam splitters (766) disposed proximate said output surface, said polarization beam splitters (766) collecting and polarizing substantially all of said radiation into a first polarization (768) and a second polarization (770). Radiation of said first polarization (768) is transmitted and radiation of said second polarization (770) is reflected toward said output surface. A wave plate (772) is disposed in a path of said radiation of said second polarization (770). |