Abstract: A light fixture for high temperature lights with a fluid cooling system operably secured thereto designed to provide optimal cooling using minimal resources and materials. The fluid may be air, water, coolant or the like. An improved heat sink positioned between the cooling fluid and the light provides optimal fluid flow geometries and creates at least one of three possible optimized cooling conditions: First, by forcing fluid to rush through one or more restricting apertures its velocity may be increased by the localized pressure drop. Second, by positioning the heat sink heat exchange structure immediately downstream of the restricting apertures and forcing the fluid flow to change direction while within the confines of the heat exchange structure. Third, the fluid flow may be bifurcated to flow bilaterally through both ends of the heat sink at once in parallel.

Abstract: A smoke detector of an obscuration type has an effective light propagation path of substantially greater length than the light propagation paths of conventional obscuration-type smoke detectors to provide increased smoke detection sensitivity without increased background noise or numbers of false alarm incidents. The smoke detector has a light source that emits a light beam that propagates into a detection chamber composed of first and second optical components having respective first and second opposed light reflecting surfaces. The light reflecting surfaces reflect the light beam across the detection chamber multiple times before the reflected light beam is incident on a light detector. The multiple reflections of the light beam increase its effective path length of propagation within the detection chamber to provide the increased smoke detection sensitivity.

Abstract: A smoke detector of an obscuration type has an effective light propagation path of substantially greater length than the light propagation paths of conventional obscuration-type smoke detectors to provide increased smoke detection sensitivity without increased background noise or numbers of false alarm incidents. The smoke detector has a light source that emits a light beam that propagates into a detection chamber composed of first and second optical components having respective first and second opposed light reflecting surfaces. The light reflecting surfaces reflect the light beam across the detection chamber multiple times before the reflected light beam is incident on a light detector. The multiple reflections of the light beam increase its effective path length of propagation within the detection chamber to provide the increased smoke detection sensitivity.

Abstract: A multi-path reflective color liquid crystal display projection system utilizes one color separating dichroic mirror in combination with polarizing beam splitters and reflective liquid crystal displays to provide a high resolution, high brightness display. The dichroic mirror separates two color components (e.g., green and one of the red and blue components) and from the other (e.g., the other of the red and blue components). A color light separating polarizing beam splitter the receives the two selected color components of light and separates them from each other.

Abstract: A color liquid crystal display projector has a light source with a radiating element (e.g., arc or incandescent) and a liquid crystal display (LCD). The LCD includes an array of multiple picture elements or pixels that each have separate color component sub-pixels (e.g., red, green and blue). Multiple differently inclined dichroic mirrors angularly separate the light into light beams of different color components. An integrating lens array relay system has a pair of planar lens arrays that form multiple spatially separated images of the angularly-color separated light components. An array of microlenses is positioned adjacent to the LCD. Each microlens is in one-to-one alignment with LCD pixels along at least one dimension and images the spatially separated images upon multiple pixels in at least the one dimension.

Abstract: A color liquid crystal display projector having a light source with a radiating element and a liquid crystal display (LCD). The LCD includes an array of multiple picture elements or pixels that each has separate color component elements. A microlens array is positioned adjacent to the liquid crystal display to direct light from the light source into the picture elements. Illumination imaging components cooperate with the microlens array to image the radiating element toward the separate color component elements of the liquid crystal display. Multiple differently inclined dichroic mirrors split the light into light beams of different color components that are imaged onto the appropriate color component elements of the liquid crystal display.

Abstract: A high efficiency polarizing converter receives generally collimated light of arbitrary polarization and converts it to light of a selected polarization with minimal loss or absorption of light. In one embodiment, the polarizing converter has a generally planar configuration that is suitable for flat panel displays, LCD projectors, and other display applications.

Abstract: An image display system such as an LCD projection display includes an illumination homogenizer and a centrifugal relay lens system. The illumination homogenizer, such as a reflective tunnel homogenizer or integrator, efficiently provides uniform distribution of light over a region matched to the configuration of an LCD, or other type of image source. The centrifugal relay lens system includes, for example, an S-curve aspheric lens surface that functions to increase the illumination distribution toward the edges and corners of the image source relative to the center. The projection system provides illumination with improved uniformity and efficiency while also providing a shortened optical pathway.

Abstract: The present invention includes an invertible and orthoscopic LCD projector having a LCD panel for providing display information that is projected toward a display screen to form a display image. In a preferred embodiment, a converging Fresnel lens is positioned to receive the display information from the LCD panel and form a display object corresponding to the display image. The converging Fresnel lens has an optical center offset from the optical center of the LCD panel in an elevation direction and defines a projection optical axis that extends toward the display screen along an elevation angle in the elevation direction. The Fresnel lens is tilted automatically about a tilt axis transverse to the projection optical axis and the elevation direction by an amount proportional to the elevation angle to cooperate with the offset of the Fresnel lens optical center to form an orthoscopic display image.

Abstract: A projection system includes a collection lens that minimizes apparent magnification of the light source, so that the resulting system more nearly conforms to a point source idealization. Attendant benefits include improved collimation, a smaller projection lens, and a greater depth of focus. The collection lens is desirably of a "wrap around" configuration to maximize light collection while contributing to reduced source magnification. The opposite side of the collection lens can be provided with a convex lens of Fresnel form. Use of the Fresnel optic moves the principal plane of the collection lens closer to the light source, further minimizing the source's apparent magnification. The projection system additionally includes condensing optics formed with a deliberate asymmetry so as to provide more uniform illumination of a rectangular image plane. The Fresnel surface of the collection lens can be designed to provide this asymmetry.

Abstract: The present invention includes a projector illumination system having a light source positioned between a condenser lens and a light-collecting reflector. The light source includes a bulb that is urged under compression against a surface of the condenser lens. The condenser lens receives a flow of cooling air over a surface opposite that against which the light source is in contact to minimize deformation of the condenser lens caused by heat emanating from the light source.

Abstract: The present invention includes a LCD projector having a light source for directing light through a LCD and a projection lens assembly toward a display screen to form a display image. The light source and the LCD being encased within a main projector housing. The projection lens assembly being supported and carried by a retractable carrier between operating and stowage positions. In a preferred embodiment, the retractable carrier positions the projection lens assembly in its operating position outside the main body housing.

Abstract: The present invention includes a projector illumination system having a light source positioned between a condenser lens and a light-collecting reflector. The light source includes a bulb that is urged under compression against a surface of the condenser lens. The condenser lens receives a flow of cooling air over a surface opposite that against which the light source is in contact to minimize deformation of the condenser lens caused by heat emanating from the light source.

Abstract: The present invention includes an invertible and orthoscopic LCD projector having a LCD panel for providing display information that is projected toward a display screen to form a display image. In a preferred embodiment, a converging Fresnel lens is positioned to receive the display information from the LCD panel and form a display object corresponding to the display image. The converging Fresnel lens has an optical center offset from the optical center of the LCD panel in an elevation direction and defines a projection optical axis that extends toward the display screen along an elevation angle in the elevation direction. The Fresnel lens is tilted automatically about a tilt axis transverse to the projection optical axis and the elevation direction by an amount proportional to the elevation angle to cooperate with the offset of the Fresnel lens optical center to form an orthoscopic display image.