Abstract: One or more disc-shaped angular shear plates each include a region thereon having a thickness that varies with a nonlinear function. For the case of two such shear plates, they are positioned in a facing relationship and rotated relative to each other. Light passing through the variable thickness regions in the angular plates is refracted. By properly timing the relative rotation of the plates and by the use of an appropriate polynomial function for the thickness of the shear plate, light passing therethrough can be focused at variable positions.

Abstract: An optical system for use in projection based displays includes a plurality of solid state light sources associated with a plurality of total internal reflection based compound hyperbolic emitters, a graduated dichroic filter based device for homogenizing light output from the plurality of solid state light sources, a ferro-electric liquid crystal on silicon device for illumination with light output from the array of solid state light sources, and a polarization diffuser for homogenization of light at the ferro-electric liquid crystal on silicon device, wherein the polarization diffuser is positioned at a point in space, in the optical system, where the size of a beam of light transmitted from the graduated dichroic filter based device is substantially at a maximum.

Abstract: A light reflector apparatus using an illumination optical fiber to produce a uniform illumination pattern is disclosed. By controlling the propagation of light in the core and cladding regions of an optical fiber, uniform light emission along the length of the fiber can be achieved. Using the illumination fiber as a light source in an open cusp reflector assembly provides for uniform dispersion of the emitted light over the exit faces of the reflector.

Abstract: A color-separation prism assembly comprises first, second and third prisms. The first and second prisms have entrance surfaces, exit surfaces, and partially-reflecting surfaces, wherein the entrance surface of the second prism is separated by an air gap from the partially-reflecting surface of the first prism. The third prism has an entrance surface and an exit surface, wherein the entrance surface of the third prism is adjacent to the partially-reflecting surface of the second prism. The first prism has a cut-out serving as a flare-stop stop, and providing relief so as to allow the entrance surface of the third prism to slide across a plane disposed over the cut-out into a volume defined by the cut-out. The plane is formed as an extension of the partially-reflecting surface of the first prism. An optical axis passes through the first, second and third prisms. The optical axis passes at normal angles through the entrance surface of the first prism, and the exit surfaces of the first, second and third prisms.

Abstract: A focusing assembly includes features that allow numerical aperture to be reduced and optimized by reducing aberrations and ghost reflections and easily controlling stop size, thereby increasing depth-of-focus. The assembly includes a single, bi-aspheric focusing lens that optimizes image quality at a specific off-axis field point. Passage of excessively divergent radiation is prevented by a baffle having a sharp, flared edge that minimizes reflection. A second aperture or baffle can be included to restrict high-divergence radiation emerging from the bi-aspheric focusing lens. All interior surfaces of the focusing assembly are preferably blackened, once again to minimize internal reflections.

Abstract: Laser diode bars with a plurality of light emitting facets have the light from those facets coupled into corresponding fibers of a fiber optic bundle via a microlens having a superconic cross section. An improvement in energy coupling of the typically less than 85 percent to up to 95 percent is achieved.

Abstract: A lens element (40) is formed from a monolithic unit (46) having two sections (46A and 46B) aligned on an optical axis. A selected one of the sections has an axial gradient refractive index, and the other has a homogeneous refractive index. A first surface 42 is generated one section and a second surface is generated on the other. The axial gradient index material may be selected such that third order spherical aberration of the element is zero. The axial gradient index material may be selected such that similarly constructed elements having shape factors between about 0 and 2.0 also have zero third order spherical aberration. Another element (20) may be formed entirely from an axially graded refractive index material. The refractive index preferably varies as a non-linear function of at least distance along the optical axis. The refractive index function and index change may be selected such that a selected third order aberration is zero or some constant value over a wide range of shape factor.