Abstract: Thin freestanding nitride films are used as a growth substrate to enhance the optical, electrical, mechanical and mobility of nitride based devices and to enable the use of thick transparent conductive oxides. Optoelectronic devices such as LEDs, laser diodes, solar cells, biomedical devices, thermoelectrics, and other optoelectronic devices may be fabricated on the freestanding nitride films. The refractive index of the freestanding nitride films can be controlled via alloy composition. Light guiding or light extraction optical elements may be formed based on freestanding nitride films with or without layers. Dual sided processing is enabled by use of these freestanding nitride films. This enables more efficient output for light emitting devices and more efficient energy conversion for solar cells.

Abstract: A light emitting diode includes a first doped semiconductor layer, an active region and a second doped semiconductor layer. The first reflective electrode of the light emitting diode is connected to the edge surfaces of the first doped semiconductor layer. The second reflective electrode includes an optically transparent layer and is connected to the second doped semiconductor layer. The second reflective electrode may include a plurality of electrically conductive contacts extending from a reflective conductive metallic layer through a transparent layer. A method is described for fabricating the light emitting diode.

Abstract: A projection display system has at least one light-recycling illumination system and at least one imaging light modulator. The light-recycling illumination system includes a light source that is enclosed within a light-recycling cavity. The light source is a plurality of light-emitting diode that emits light, and a fraction of that light will exit the light-recycling cavity through an aperture. The light-recycling cavity recycles a portion of the light emitted by the light source back to the light source in order to enhance the luminance of the light exiting the aperture. The fraction of the light that exits the aperture is partially collimated and is directed to the imaging light modulator. The imaging light modulator spatially modulates the partially collimated light to form an image.

Abstract: Optical elements in an optical device simulate the optical perspective of animals, reptiles, fish, insects, birds and other creatures for a human viewer. The optical elements are one or more lenses, filters, diffraction gratings, mirrors, prisms, polarizers or apertures or combinations thereof. The optical device can be a monocle, a monocular, a telescope, binoculars, goggles, a mask, a visor or a helmet. The optical element can be permanently mounted in the optical device. The optical element can be removeably mounted in the optical device. The optical element can be sequentially moved through the optical device.

Abstract: This invention is an illumination system that incorporates a light emitting diode and a partially reflecting optical element. The light emitting diode emits internally generated light having a first angular range and reflects incident light with high reflectivity. The partially reflecting optical element transmits a first portion of the internally generated light with a second angular range, smaller than the first angular range, and reflects a second portion of the internally generated light back to the light emitting diode, where the second portion is reflected by the light emitting diode. The partially reflecting optical element can be a pyramid, an array of pyramids, a first and second orthogonal arrays of prisms or a bandpass filter. Utilizing a partially reflecting optical element and light recycling can increase the effective brightness and the output efficiency of the illumination system.

Abstract: A wavelength conversion chip is formed by depositing a wavelength conversion material layer on a substrate, segmenting the wavelength conversion layer into a plurality of wavelength conversion chips, and then removing the wavelength conversion chips from the substrate. The wavelength conversion of the chips can be increased by thermal annealing or radiation annealing of the wavelength conversion material. Optical coatings or light extraction elements can be fabricated on the wavelength conversion layer.

Abstract: The exposure of selected optical materials to large area electron beam irradiation can raise the refractive index of the optical material to allow the fabrication of waveguides, optical fibers, gradient index lenses, interference filters, antireflection coatings, heat reflective thermal control coatings and other optical elements.

Abstract: The invention provides a process for forming optical components and new optical materials utilizing electron beam irradiation. The process comprises selectively irradiating optical materials to alter their index of refraction gradient three dimensionally. With the inventive process, new optical materials can be created that have enhanced optical properties over the un-irradiated material. The invention also provides a process in which optical components can be fabricated without requiring a planar/multiple layer process, thereby simplifying the fabrication of these optical components. The inventive process uses a controlled electron beam to alter the properties of optical materials. By using the radiation of a controlled electron beam, controlled changes in the index of refraction gradient of optical materials can be obtained. Further, radiation of the electron beam can be used to create new optical materials from materials not previously believed to be suitable for optical applications.

Abstract: A method and apparatus for depositing solder paste on a printed wiring board has a stencil with a pattern of multiple apertures. The pattern aligns with a through-hole in the printed wiring board when the stencil is in physical contact with the printed wiring board. A squeegee arrangement applies solder paste through the multiple apertures in the stencil through the through-hole of the printed wiring board to the upper surface of the printed wiring board for securely mounting electronic components to the upper surface of the printed wiring board, for providing a thermal path for the heat sinks of the electronic components and for providing a low inductance electrical path to ground for the electrical components.

Abstract: An aspheric optical element corrects the non-linearity of the scan line in a ROS. The optical element can be either the wobble correction mirror, the last optical element in the ROS, or the output window, subsequent to the ROS. The optical element deflects the scan beam to cancel the non-linearity of the scan line caused by the residual errors in the ROS lens design. The aspheric optical element can also correct scan line bow.

Abstract: Gallium nitride substrates are formed by etching a gallium nitride layer on a sapphire substrate or by selective area regrowth of a gallium nitride layer first deposited onto a sapphire substrate. The gallium nitride layers are bonded to a support substrate and a laser pulse directed through the transparent sapphire detaches the gallium nitride layers from the sapphire substrate. The gallium nitride layers are then detached from the support substrate forming freestanding gallium nitride substrates.

Abstract: A dual III-V nitride laser structure has a thick current spreading layer on a sapphire substrate and a trench extending into the current spreading layer to reduce thermal cross-talk between the dual lasers.

Abstract: A laser driver uses a switch, a current mirror, a control transistor and two current generators to control the ON and bias currents in a laser diode. In the bias mode the current from one generator is shared by one half of the current mirror and the adjustable control transistor. The other current generator then drives the other half of the mirror circuit and the laser diode in parallel, resulting in the laser diode getting the same amount of current that the control transistor gets. In the ON mode, the switch cuts off the first half of the current mirror, which is mirrored in the other half, so that all of the other generator current is used in the laser diode. The current drivers are adjustable to the ON current and the control transistor current is adjustable to the bias current.

Abstract: A heating element adjusts the curvature of a cylindrical wobble correction mirror to compensate and correct the scan line bow for an optical scanner. A current applied through the heating element along one side of the mirror will cause the mirror to bend vertically for a horizontal beam to adjust the scan line bow for a single beam and approximately equalize the scan line bow for multiple beams.

Abstract: A honeycomb structure is formed integral with a raster output scanning system housing. A constrained layer damper is bonded to the honeycomb structure and the raster output scanning system is mounted on the constrained layer damper. The honeycomb structure and constrained layer damper provide support and reduce vibrations to the raster output scanning system. The cells of the honeycomb structure can be irregular in height, thickness, density or shape to further support and damp vibrations.

Abstract: A fluid-filled heat sink is positioned on the emission surface of a laser diode. The light beam emitted by the laser diode aperture will propagate though the optically transparent fluid to be transmitted through an output window of the heat sink. Heat generated by the laser diode will be transferred by the thermally conductive fluid to the heat sink housing which will radiate the heat or transfer the heat to a secondary heat sink.

Abstract: A method is provided for fabricating a nitride based resonant cavity semiconductor structure with a first distributed Bragg reflector on a sapphire substrate, a second substrate bonded to the first distributed Bragg reflector, the sapphire substrate removed by laser-assisted epitaxial lift-off, and fabricating a second Bragg reflector on the semiconductor structure opposite the first distributed Bragg reflector. The nitride based resonant cavity semiconductor structure can be a VCSEL, LED or photodetector, or a combination of said devices.

Abstract: A beam splitter cube and two roof mirrors are used as a beam spacer to interlace and closely space four parallel laser beams.

Abstract: A six sided refractive / reflective optical element controls the separation between four parallel laser beams. Two beams will be reflected off the optical element and two beams will be refracted within the optical element with each reflection and refraction being off a different side of the optical element to form four closely spaced parallel light beams.