Abstract: A lighting device has a light source, a reflector dish with a central opening facing the light source, and a lens between the light source and the reflector dish. The lens is so arranged that light emitted from the source towards the central opening of the reflector dish is diffracted away from the central opening. The reflector dish is arranged to reflect light received from the source through the lens back past the lens and source.

Abstract: In one method of and apparatus for varying the luminosity of illumination, each of a plurality of light sources has an on state in which it emits light and an off state in which it does not emit light. Each of the plurality of light sources is switched cyclically between the on state and the off state in a sequence over a cycle period. The switching sequence is selected such that the number of said light sources that are on is uniform over the cycle. The luminosity of the illumination is varied by varying the proportion of each cycle for which each light source is switched on.

Abstract: Some embodiments provide a luminance-enhanced light source. These embodiments include a thin-film LED mounted on a substrate and with a defined upper surface approximately hemispherically emitting light, with the upper surface being diffusely transmissive, a lower first layer of identically defined linear prismatic film separated from the upper surface by a non-evanescent air gap so as to cover the upper surface, a upper second layer of linear prismatic film, identical to but oriented orthogonally to the first layer, and a circumferential vertical reflective wall bordering on both of the first and second layers and extending in height from the substrate to the top of the second layer.

Abstract: The present embodiments provide methods and systems for use in providing enhanced illumination. Some embodiments include at least two light sources and one or more smoothly rotating wheels, where the one or more wheels comprises at least one mirror sector, the circumferential portion of the mirror sector is the inverse of the number of said sources, a first source of the sources is so disposed that the mirror sector reflects light from the first source into a common output path, where the first source pulsing such that a duty cycle of the first source corresponds to a time the mirror sector reflects light from the first source into the common output path.

Abstract: An embodiment of a method of designing a grooved reflector comprises selecting two given wavefronts; and designing two surfaces meeting at an edge to form a groove such that the rays of each of the given wavefront become rays of a respective one of the given wavefronts after a reflection at each of the surfaces. Multiple grooves may be combined to form a mirror covering a desired area. A mirror may be manufactured according to the design.

Abstract: An embodiment of a collimating downlight has front-mounted blue LED chips facing upwards, having a heat sink on the back of the LED chips exposed in ambient air. The LED chips are mounted in a collimator that sends their blue light to a remote phosphor situated near the top of the downlight can. Surrounding the remote phosphor is a downward-facing reflector that forms a beam from its stimulated emission and reflected blue light. The phosphor thickness and composition can be adjusted to give a desired color temperature.

Abstract: Light sources comprise an emitter of photostimulative light, such as one or more blue LEDs, a reflector, which may be a diverging cone, disposed to reflect light from the LEDs towards an exit aperture, a tailored aspheric lens that further collimates the light from the reflector, a short-pass filter receiving and transmitting the collimated light, a dielectric concentrator receiving the light transmitted by the filter from the LEDs and concentrating it upon the exit aperture, a dielectric emission optic on the outside of the exit aperture to receive the concentrated light, and a layer of photosensitive phosphor deposited on the outside of the emission optic, the phosphor responsive to the LED light to emit light of a longer wavelength.

Abstract: The present embodiments provide systems, backlights, films, apparatuses and methods of generating back lighting. Some embodiments provide backlights that include a cavity with at least one interior light source and diffusely reflecting wall of high reflectivity, a top surface with multiple intermittently spaced holes allowing exit of light generated by the light sources, and external collimators extending from each of the holes such that the external collimators spatially expand and angularly narrow the light exiting the holes.

Abstract: Some embodiments provide luminance-preserving non-imaging backlights that comprise a luminous source emitting light, an input port that receives the light, an injector and a beam-expanding ejector. The injector includes the input port and a larger output port with a profile that expands away from the input port acting via total internal reflection to keep x-y angular width of the source image inversely proportional to its luminance. The injector is defined by a surface of revolution with an axis on the source and a swept profile that is a first portion of an upper half of a CPC tilted by its acceptance angle. The beam-expanding ejector comprising a planar waveguide optically coupled to the output port of the injector. The ejector includes a smooth upper surface, and a reflective lower surface comprising microstructured facets that refract upwardly reflected light into a collimated direction common to the facets.

Abstract: A condenser for directing light from a UHP arc lamp or other generally cylindrical source onto a target such as a microdisplay in line with a front end of the lamp comprises a primary mirror to direct light from the source towards the back end of the condenser, and a secondary mirror at the back end of the condenser to direct the light from the primary mirror onto the target.

Abstract: A general method is disclosed of designing two-component dichroic short-pass filters operable for incidence angle distributions over the 0-30° range, and specific preferred embodiments are listed. The method is based on computer optimization algorithms for an N-layer design, specifically the N-dimensional conjugate-gradient minimization of a merit function based on difference from a target transmission spectrum, as well as subsequent cycles of needle synthesis for increasing N. A key feature of the method is the initial filter design, upon which the algorithm proceeds to iterate successive design candidates with smaller merit functions. This initial design, with high-index material H and low-index L, is (0.75 H, 0.5 L, 0.75 H)?m, denoting m (20-30) repetitions of a three-layer motif, giving rise to a filter with N=2m+1.

Abstract: Optical systems are described that have at least one source of a beam of blue light with divergence under 15°. A phosphor emits yellow light when excited by the blue light. A collimator is disposed with the phosphor and forms a yellow beam with divergence under 15°. A dichroic filter is positioned to transmit the beam of blue light to the phosphor and to reflect the beam of yellow light to an exit aperture. In different embodiments, the beams of blue and yellow light are incident upon said filter with central angles of 15°, 22°, and 45°. The filter may reflect all of one polarization and part of the other polarization, and a polarization rotating retroreflector may then be provided to return the unreflected light to the filter.

Abstract: In some embodiments, an apparatus for use generating illumination is provided that comprises a reflective base, a first light source positioned proximate the reflective base, and a reimaging reflector positioned partially about the first light source, where a percentage of light emitted from the first light source is reflected from the reimaging reflector to the reflective base adjacent the first light source establishing a first real image. The reimaging reflector can further comprise a first sector of a first ellipsoid and a second sector of a second ellipsoid, where the first and second sectors establish the first and a second real image. Further embodiments provide a lens that includes a reimaging reflector that receives light and reflects the light establishing a first real image. The reimaging reflector can further comprise a plurality of sectors that reflect light to establish first and second real images.

Abstract: The present embodiments provide methods and systems to homogenize illumination on a target.

Abstract: An optical device for coupling the luminous output of a light-emitting diode (LED) to a predominantly spherical pattern comprises a transfer section that receives the LED's light within it and an ejector positioned adjacent the transfer section to receive light from the transfer section and spread the light generally spherically. A base of the transfer section is optically aligned and/or coupled to the LED so that the LED's light enters the transfer section. The transfer section can comprises a compound elliptic concentrator operating via total internal reflection. The ejector section can have a variety of shapes, and can have diffusive features on its surface as well, including a phosphor coating. The transfer section can in some implementations be polygonal, V-grooved, faceted and other configurations.

Abstract: Some embodiments provide an illumination optical system. The optical system can include a first surface and a second surface. Each of the first and second surfaces can further comprises a multiplicity of corresponding Cartesian-oval lenticulations such that each lenticulation of the first surface focuses a source upon a corresponding lenticulation of the second surface and each lenticulation of the second surface focuses a target upon a corresponding lenticulation of the first surface.

Abstract: The embodiments provide methods for use in designing and/or manufacturing optical systems. Some embodiments further provide for the optical systems generated utilizing the methods for use in designing and/or manufacturing. In some embodiments, a method simultaneously generates first and second sets of span points defining first and second surfaces, respectively, where sets of span points are interdependent. The method curve fits through the first and second sets of span points defining initial first and second spines, smoothes the curve fittings such that tangent vectors are perpendicular to normal vectors, and defines patches of the first and second surfaces relative to the first and second spines. Some embodiments simultaneously generate the first and second sets of span points by alternatively determining the points of the sets based on propagation of input wavefronts and associated output wavefronts relative to previously determined points.

Abstract: The diffuse reflectivity of an LED source is utilized to recycle some of its emission, thereby enabling a luminaire to escape the étendue limit. Retroreflectors intercept the rays destined for the outer part of the luminaire aperture, which can then be truncated. The resulting smaller aperture has the same beam-width as the full original, albeit with lesser flux due to recycling losses. A reduction to half the original area is possible.

Abstract: In one embodiment of a solar concentrator, a tailored aspheric lens augments the solar-concentrator performance of a concave mirror, widening its acceptance angle for easier solar tracking, making it more cost-competitive for ultra-large arrays. The molded-glass secondary lens also includes a short rod for reducing the peak concentration on a photovoltaic cell that is optically bonded to the end of the rod. The Simultaneous Multiple Surface method produces lens shapes suitable for a variety of medium and high concentrations by mirrored dishes. Besides the rotationally symmetric parabolic mirror itself, other aspheric deviations therefrom are described, including a free-form rectangular mirror that has its focal region at its edge.

Abstract: In some embodiments, an apparatus for use generating illumination is provided that comprises a reflective base, a first light source positioned proximate the reflective base, and a reimaging reflector positioned partially about the first light source, where a percentage of light emitted from the first light source is reflected from the reimaging reflector to the reflective base adjacent the first light source establishing a first real image. The reimaging reflector can further comprise a first sector of a first ellipsoid and a second sector of a second ellipsoid, where the first and second sectors establish the first and a second real image. Further embodiments provide a lens that includes a reimaging reflector that receives light and reflects the light establishing a first real image. The reimaging reflector can further comprise a plurality of sectors that reflect light to establish first and second real images.