Abstract: An optical light engine (100) includes one or more light-emitting diode (LED) panels (101, 102, 103) that are combined into a common path and directly imaged onto panel device to provide a source of light to a microdisplay panel (109). Preferably, the LED panel (101, 102, 103) is shaped such that the aspect ratio of light propagating the LED panel is substantially equal to the light received at the microdisplay panel (109). An aspect ratio of 4:3 or 16:9 is typically selected in view of the sizes of the LED panels used in the light engine.

Abstract: A device used in laser display systems for despeckling includes a liquid crystal cell disposed in sandwiched relation between an input and a grounded electrode. A glass cover overlies each electrode. In a first embodiment, the cell may include vertically or randomly oriented liquid crystal molecules and the liquid crystal cell is larger than a laser beam in size for random phase modulation or retardation. Light loss due to diffraction and scattering are substantially eliminated in the absence of pixel structures. In another embodiment, the input electrode is divided into two separate parts. Vertically aligned liquid crystal molecules rotate and follow field fringes created by applying a first voltage to the input electrodes. Additional embodiments include a device that has two wedge-shaped liquid crystal layers, a device that includes plural field-induced gradient index prisms, a device including a tilted mirror, and composite devices.

Abstract: A device used in laser display systems for despeckling includes a liquid crystal cell disposed in sandwiched relation between an input and a grounded electrode. A glass cover overlies each electrode. In a first embodiment, the cell may include vertically or randomly oriented liquid crystal molecules and the liquid crystal cell is larger than a laser beam in size for random phase modulation or retardation. Light loss due to diffraction and scattering are substantially eliminated in the absence of pixel structures. In another embodiment, the input electrode is divided into two separate parts. Vertically aligned liquid crystal molecules rotate and follow field fringes created by applying a first voltage to the input electrodes. Additional embodiments include a device that has two wedge-shaped liquid crystal layers, a device that includes plural field-induced gradient index prisms, a device including a tilted mirror, and composite devices.

Abstract: A solid state directional lighting device includes a semiconductor light source emitting a primary short wavelength light and a light collimation component disposed in light-reflecting relation to the light source to generate a collimated light with beam divergence angle less than forty degrees (40°). A luminescent nanocrystal conversion layer is disposed in the path of the collimated light and includes a luminescent nanocrystal conversion layer including luminescent nanocrystal particles with nano-particles sizes less than fifteen nanometers (15 nm). The luminescent nanocrystal particles absorb at least a portion of the collimated short wavelength light and convert the absorbed light into at least one long wavelength spectral light. A mixture of leakage primary short wavelength light and long wavelength light converted by the luminescent nano-particles produces a directional white light with luminous efficacy of at least one hundred lumens per Watt (100 lm/W).

Abstract: A solid state lighting device includes a first group of semiconductor light emitting devices that produces a yellowish white light, a second group of semiconductor light emitting devices that includes at least one light emitting device that produces a reddish orange light, and a third group of semiconductor light emitting devices that includes at least one wavelength down-converted white light device. A combination of the second and third groups produces a sub-mixture of reddish warm white light. A combination of the first, second and third groups produces a mixture of warm white light with a correlated color temperature between 2700k to 3500K and a color rendering index higher than 85.

Abstract: A semiconductor lighting device includes a semiconductor light emitter packaged on a reflective substrate to emit a first light and a remote wavelength conversion layer on a back-transferred light path to convert the back-transferred first light into a forward second light. A filter is disposed on a light emitting forward path with a space to the semiconductor light emitter to reflect back at least a portion of the first light. A diffusive member may be positioned outside of the filter to diffuse the forward passing light before it exits from the semiconductor lighting device. As a second aspect of this invention, a solid state lighting device includes a short wavelength semiconductor emitter; a long wavelength semiconductor emitter with wavelength in reddish orange range; a filter on a light emitting forward path to reflect back a portion of short wavelength first light; and a wavelength conversion component on a back-transferred light path.

Abstract: One or more embodiments of the present invention provide apparatuses, methods and systems to form a thin LED backlight unit for a large-screen flat-panel display. The backlight unit is able to achieve improved color mixing within a shorter mixing distance than the conventional art, while maintaining desired brightness uniformity, thereby allowing for a shorter bezel of a display device. One or more embodiments of the present invention include one or more light guides, which, by operating together, provide thin backlight units. High system efficiency is provided by introducing a recycling enhancement component, and uniform color distribution is achieved by incorporating color shift compensation. Multiple light guides are arranged adjacent to one another can offer a progressive scan illumination feature.

Abstract: A projector has a transmissive spatial light modulator backlit by a collimated illuminator that includes a light source that outputs red, green, blue (RGB) light, and a combiner disposed in light-receiving relation to the light source for mixing or combining the RGB light. The combiner has cavity features associated therewith for outputting collimated light, where such light preferably has a divergent cone angle less than plus or minus fifteen degrees (+/?15°).

Abstract: A backlighting apparatus for a flat panel LCD display includes an elongate light guide having a front wall through which travels polarized light in a direction toward the LCD display. An RGB LED set is positioned adjacent a first end wall of the light guide so that light enters the light guide from the first end wall. A retardation and reflection film covers respective external surfaces of the bottom wall and a second end wall. Microlenses are formed in the front wall along its extent and each microlens is filled with a birefringent material. Light emitted by the LED set travels through a collimated light coupling module and exits the light guide through the birefringent microlenses in polarized form toward the LCD display. The viewing angles and angular light distributions of the LCD display in vertical and horizontal directions are optimized for enhancing the brightness without involving DBEF and BEF.

Abstract: The present invention discloses a side illumination LED lighting device which includes at least one semiconductor light emitter mounted on a thermally conductive substrate and positioned within a reflective cavity such that the forward light path of the LED is directed towards a reflective member. The reflective member is effective in re-directing the light from the semiconductor light emitter such that the light is extracted from the side of the lighting device through a substantially transparent output window, thereby provide a side illumination solid-state semiconductor lighting device. The lighting device may further include a wavelength conversion element to facilitate the production of a white light that can be extracted from the side of the lighting device.

Abstract: A semiconductor lighting device includes at least one semiconductor light emitter and at least one wavelength converting element, physically separated from the light emitter. At least one wavelength converting element has a reflective member underneath it, so that both primary light and converted light from the wavelength converting layer become a forward transferred light preventing from backscattering loss into the light emitter. The reflective member may be a thermal conductive element to effectively remove the heat from the wavelength converting element. Accordingly, the remote wavelength conversion on a reflective surface improves the thermal stability of the wavelength conversion material and prevents backscattering loss to produce a higher radiance result from the device.

Abstract: A solid state lighting device includes a light mixing cavity enclosed by a diffusive output window, heat sink walls, and a light-redirection member. A plurality of circumferentially spaced apart light emitters is secured to an interior surface of the heat sink walls. The diffusive output window and light-redirection member are therefore disposed at opposite ends of the light mixing cavity. A semiconductor lighting device driver is disposed external to the light mixing cavity in electrical communication with the light emitters. Light emitted by the plurality of light emitters is reflected from the light-redirection member and from the heat sink walls prior to exiting the light mixing cavity through the diffusive output window.

Abstract: A high luminous flux warm white solid state lighting device with a high color rendering is disclosed. The device comprising two groups of semiconductor light emitting components to emit and excite four narrow-band spectrums of lights at high luminous efficacy, wherein the semiconductor light emitting components are directly mounted on a thermal effective dissipation member; a mixing cavity for blending the multi-spectrum of lights; a back-transferred light recycling member deposited on top of an LED driver and around the semiconductor light emitters; and a diffusive member to diffuse the mixture of output light from the solid state lighting device. The solid state lighting device produces a warm white light with luminous efficacy at least 80 lumens per watt and a color rendering index at least 85 for any lighting application.

Abstract: A semiconductor lighting device includes a semiconductor light emitter packaged on a reflective substrate to emit a first light and a remote wavelength conversion layer on a back-transferred light path to convert the back-transferred first light into a forward second light. A filter is disposed on a light emitting forward path with a space to the semiconductor light emitter to reflect back at least a portion of the first light. A diffusive member may be positioned outside of the filter to diffuse the forward passing light before it exits from the semiconductor lighting device. As a second aspect of this invention, a solid state lighting device includes a short wavelength semiconductor emitter; a long wavelength semiconductor emitter with wavelength in reddish orange range; a filter on a light emitting forward path to reflect back a portion of short wavelength first light; and a wavelength conversion component on a back-transferred light path.

Abstract: One or more embodiments of the present invention provide apparatuses and systems to form edge-illuminated LED backlight units for flat-panel LCD displays. The backlight unit is able to achieve uniform color and brightness distribution with very small dimensions of depth and bezels. One or more embodiments of the present invention include a light guide coupled to a light guide plate, which, by operating together, provide simple, efficient, few LEDs and low cost backlight units. Effective coupling structures provide high system efficiency.

Abstract: One or more embodiments of the present invention provide apparatuses, methods and systems to form a thin LED backlight unit for a large-screen flat-panel display. The backlight unit is able to achieve improved color mixing within a shorter mixing distance than the conventional art, while maintaining desired brightness uniformity, thereby allowing for a shorter bezel of a display device. One or more embodiments of the present invention include one or more light guides, which, by operating together, provide thin backlight units. High system efficiency is provided by introducing a recycling enhancement component, and uniform color distribution is achieved by incorporating color shift compensation. Multiple light guides are arranged adjacent to one another can offer a progressive scan illumination feature.

Abstract: The invention discloses a high efficiency incandescent and Compact Fluorescent (CFL) bulb replacement LED lamp having a good color reproduction. The LED light bulb includes two groups of semiconductor light emitters and a luminescent material to emit four different spectrums of light. The two groups of semiconductor light emitters are enclosed around an interior wall of the light bulb housing, which has a plurality of fins at an exterior surface for effective heat dissipation. A high reflective member having a dome shape in the center is disposed under the two groups of semiconductor light emitters to redirect the emission and excitation lights from the two groups of semiconductor light emitters and recycle the backscattered light for multi-spectrum light mixing. The LED-light bulb further includes a single power line connecting to the two groups of semiconductor light emitters and a high efficiency electrical AC/DC conversion and control device.

Abstract: An image presentation device (100) incorporates an optical combiner (130) that utilizes a multi-state optical switch (131, 137) for use with a plurality of colored light sources (122, 124,126). The switch (131,137) includes an electronically switchable holographic optical element HOE (131) having a first and a second mode of operation. Light from first and second light sources (124, 126) passes through HOE (131) in a diffracted manner in at least one of the first and second modes of operation. Light from a third light source (122) is reflected by a reflector (137) in a third mode of operation. The combiner (130) operates to combine light from the various light sources (122, 124, 126) into a common light path.

Abstract: A compact micro-display engine having improved efficiency for, e.g., projection displays or personal displays. It includes an emissive micro-display without the need for external illumination, a collimation optic plate on top of micro-display and a low F/# projection optics after the collimation optic plate. The collimation optical plate may be a micro-structure lenses array or a collimation prism film, and is used to collimate wide divergent light from the emissive micro-display device into a small cone angle light which will be efficiently collected by the projection optics. A reflective mirror is deposited on the top of substrate and underneath the light emitting layer for recycling the reflected back light from the collimation optic plate. The compact micro-display projection engine controls the divergence angle of the emitted light, and provides the controlled light to the objective plane of a projection optics subsystem.

Abstract: A device (300) includes a driver circuit (200) having a field effect transistor (FET) (30), acting as a current sink, a current sense network (10), an operational amplifier (opamp) (20), and a light emitting diode (LED) (40). Current sense network (10) is connected to the source electrode (32) of FET (30), as well as to the inverting input terminal (22) of opamp (20). The non-inverting input terminal (24) of opamp (20) is coupled to a variable voltage control signal source (VDAC) (110). The output terminal (26) of opamp (20) is coupled to the gate electrode (36) of FET (30). LED (40) is connected to the drain electrode (34) of FET (30). The brightness of LED (40) is controlled by varying the amplitude of the VDAC control signal, and on/off status is controlled by a switch S1 disposed between the output terminal (26) of opamp (20) and the FET (30).