Abstract: A light collection system includes at least one light source, a light tunnel having reflective walls and a collimating plate at the light output end of the tunnel. The collimating plate includes an optical element array. The element array receives the light emitted from the light source and outputs part of the light at a desired cone angle and reflects the remainder back into the tunnel toward the light source. The light is “recycled” in the tunnel until the light either exits the collection system through the collimating plate or gets absorbed within the collection system.

Abstract: A light extraction plate can be used with a light emitting diode (LED) to efficiently extract and provide control over the spatial distribution of extracted light in terms of intensity and angle. The extraction plate can have millions of optical micro-elements and can be manufactured independently of the LED using conventional integrated circuit (IC) fabrication techniques. The extraction plate is preferably attached or bonded to an LED surface.

Abstract: A compact, light weight, efficient and cost-effective illumination system for optical displays is disclosed. The illumination system is capable of producing a self-luminous light beam of selected cross-section and spatial distribution in terms of intensity and angle. The illumination system can efficiently couple light from light sources having wide variety of sizes and shapes into light valves of various shapes and sizes. The illumination system includes a light recovery system or a polarization conversion system or a suitable combination of the foregoing.

Abstract: An apparatus and method for reducing speckle of a laser beam is disclosed. The apparatus includes a light guide, a highly reflective mirror at the input face of the light guide and a partially reflective mirror at the exit face of the light guide. A coherent laser beam is introduced into the light guide through a clear aperture in the highly reflective mirror. Within the light guide, the laser beam gets separated into plural, successive beamlets having different phase shifts, different polarization states and/or path length differences equal to or greater than the coherence length of the laser beam. The beamlets exit the light guide through the partially reflective mirror to provide output laser light with reduced speckle. The light guide can be either a solid light pipe of transmissive material or a hollow tunnel with reflective interior sidewalls.

Abstract: An optical projection system comprises a light source, a substantially planar optical element array for receiving light emitted from the light source, and a display panel for selectively outputting light from the optical element array. The optical element array includes an optically transmissive substrate material and a plurality of optical micro-elements formed on at least one surface of the substrate material. The display panel has a plurality of pixels for selectively outputting light output from the optical element array. The micro-elements can include micro-lenses, micro-prisms, micro-waveguides, or any suitable combination of the foregoing, configured to alter the characteristics of light emitted from the light source to create a desired illumination source.

Abstract: A compact polarization conversion system (PCS) for use in optical display systems is capable of emitting substantially polarized output light in response to unpolarized input light. The PCS includes a polarizer and one or more substantially planar optical element arrays in optical communication with the polarizer. The polarizer converts the input light having plural polarization states into output light having a substantially single polarization state. Each optical element array comprises a plurality of optical elements formed and positioned in a specific two-dimensional arrangement for altering at least one optical characteristic of the input light to produce desired characteristics in the output light. The optical elements can include any suitable combination of micro-waveguides, micro-tunnels, micro-lenses, micro-prisms.

Abstract: A light recycler for use in color projection display systems. The light recycler redirects light reflected by a color wheel of the projection system to increase the light output of the projection system. The light recycler is capable of setting the desired numerical aperture of the light source beam, as well as providing the desired spatial distribution of light in terms of intensity and angle. This improves the light uniformity and brightness of the image displayed by the projection system, and improves the efficiency of the system. The light recycler includes at least one substantially planar optical element array receiving the non-uniform light from the light source. The optical element array includes an optically transmissive substrate and a plurality of optical micro-elements formed in the substrate. The micro-elements act together to produce an output light beam having a desired cross-sectional area and spatial distribution of light intensity and angle.