Abstract: An Ultra High Luminance (UHL) high intensity discharge (HID) lamp is described. The lamp envelope is made of single crystal alumina (SCA) material. The fill consists mainly of mercury at densities in the range of 0.3 to 0.7 mg/mm3. The lamp is designed for applications in the projection field where small light modulation imaging devices are used. The lamp design includes a variety of burner (lamp vessel ) geometries and sealing arrangements. This lamp technology represents a major departure from the Ultra High Pressure (UHP) fused silica envelope, mercury filled, HID lamps that are currently used and overcomes the adverse effect of convection. The preferred, and described, alternative burner (vessel ) geometries are envelopes with non-uniform wall thickness, which are thicker at the tops and thinner at the bottoms; a bulbous shape which is more curved at the top than at the bottom; and placing the arc off the center axis, so that the arc is closer to the bottom than it is to the top.

Abstract: A high intensity discharge lamp, especially for optical projection systems, in one embodiment uses an anode electrode, a cathode electrode and a cylindrical envelope of single crystal (SC) sapphire. The fill may contain hydrogen, chlorine, sodium, scandium, sulfur and selenium and is under pressure exceeding 20 atmospheres. The lamp produces a continuous non-flash arc and generates a correlated color temperature between 6500 and 7000 degrees Kelvin and an efficacy exceeding 60 lumens/watt.

Abstract: A color separation optical plate is described which is superimposed onto a transmissive LCD panel. The color separation plate separates incident white light into its red/green/blue (RGB) components and guides each component through the appropriate sub-pixel (dot) of the LCD panel. The color separation plate utilizes a microprism array of direct vision microprisms each having a combination of refractive and gradient index optics to concentrate the light onto the appropriate dot and to separate the colors. This combination has the theoretical capability of increasing color LCD panel transmissivity by as much as a factor of six.

Abstract: A projection system, such as a slide film or motion picture projection system, includes a light source, a reflector, a film gate or aperture, and a screen. The reflector is formed from a deep-dish ellipse reflector by cutting the ellipse into at least three reflector sectors and then outwardly radially deforming the outer edges, the deformation occurring within a certain critical range. The deformed outer edges are then clamped by circular clamping means.