Micro display devices such as LCOS and DLP(TM) have capitalized on advancement of microelectronics fabrication technologies. Device miniaturization has created a need for high brightness light sources having low numerical apertures. Light sources based on the traditional non-imaging principles such as an ellipsoidal reflector require lamps emitting nearly a point-like source, which prompted reduction of arc sizes and increase in fill pressure in arc lamps. These requirements shorten the life and increase the cost of the lamp. In this paper, we present a novel illumination system that is based on a one-to-one imaging principle. The approach incorporates a so-called Dual Paraboloid Reflector (DPR) system in which two halves of paraboloid reflectors and a hemispherical retro-reflector are used to collect almost all the light emitted from an arc lamp. When combined with a tapered light pipe (TLP), a DPR based illumination system produces a light output having a required area, shape, numerical aperture, and a high and uniform flux density. Contrary to methods based on non-imaging principles DPR illuminators do not require those short lived short arc lamps to satisfy the needs of the projection industry. ASAP simulations of the system and experimental results are presented. The advantages of this system when applied to polarization recovery, polarization recycling, and color recycling will be discussed.
