Abstract: A light source configured to emit first light is combined with a wavelength-converting layer. The wavelength-converting layer is disposed in a path of first light, is spaced apart from the light source, and includes at least one wavelength-converting material such as a phosphor configured to absorb first light and emit second light. The wavelength-converting layer is disposed between a reflective layer and the light source. In some embodiments, the wavelength-converting layer is a thick layer.

Abstract: Amber light LEDs have a higher luminance than red light LEDs. A vast majority of images displayed on television consists of colors that can be created using amber, green and blue components, with only a small percentage of red. In one embodiment of the present invention, the typically red primary light source in a projection display system is augmented with an amber light source. Green and blue primary light sources are also provided. All the light sources are high power LEDs. The particular mixture of the red and amber light is accomplished by varying the duty cycles of the red LEDs and the amber LEDs. If the RGB image to be displayed can be created using a higher percentage of amber light and a lower percentage of red light, the duty cycle of the amber LEDs is increased while the duty cycle of the red LEDs is decreased. Light/pixel modulators for creating the full color image from the three primary light sources are controlled to compensate for the variable amber/red mixture.

Abstract: A light emitting diode module is produced using at least one light emitting diode (LED) and at least two selectable components that form or are part of a light mixing chamber that surrounds the LEDs and includes an output port. A first selectable component has a first type of wavelength converting material with a first wavelength converting characteristic and a second selectable component has a second type of wavelength converting material with a different wavelength converting characteristic. The first and second wavelength converting characteristics alter the spectral power distribution of the light produced by the LED to produce light through the output port that has a color point that is a predetermined tolerance from a predetermined color point. Moreover, a set of LED modules may be produced such that each LED module has the same color point within a predetermined tolerance.

Abstract: A white light LED for use in backlighting or otherwise illuminating an LCD is described where the white light LED comprises a blue LED over which is affixed a preformed red phosphor platelet and a preformed green phosphor platelet. In one embodiment, to form a platelet, a controlled amount of phosphor powder is placed in a mold and heated under pressure to sinter the grains together. The platelet can be made very smooth on all surfaces. A UV LED may also be used in conjunction with red, green, and blue phosphor plates. The LED dies vary in color and brightness and are binned in accordance with their light output characteristics. Phosphor plates with different characteristics are matched to the binned LEDs to create white light LEDs with a consistent white point for use in backlights for liquid crystal displays.

Abstract: An illumination device includes a light source, such as one or more light emitting diodes in an array, that produces light having a first wavelength range. A separated wavelength converting element is mounted to receive the light emitted by the light source. The wavelength converting element is physically separated from the light source along the beam path. The wavelength converting element converts the light having a first wavelength range into light having a second wavelength range. In one embodiment, a color separation element is directly coupled to the wavelength converting element. The color separation element is also physically separated from the light source. In another embodiment, the wavelength converting element is held by a heat sink by the sides.

Abstract: A lighting module includes a light output window, at least one side wall that defines a cavity and a mounting plate, and at least one light source, and at least one reflector that is within the cavity. The light output window may be one of the side walls in a side-emitting configuration. The spectral distribution of the light coming out of the light output window may be changed by manipulating the relative position of the side wall to the at least one reflector that is within the cavity.

Abstract: An illuminating member (4) that, independent of any image content, comprises a central region (5) and an enclosing region (6), wherein said enclosing region (6) is adapted to emit light of lower quality than the light emitted by the central region (5). The illuminating member is adapted to illuminate a display panel (2) of a display device. By having the enclosing region emit light of lower brightness (dimming) a significant power reduction can be achieved for a wide range of typical images while largely maintaining the perceived image quality. Further, by using light emitting elements of lower quality for the enclosing region, manufacturing costs may be reduced while largely maintaining the perceived image quality.

Abstract: Low profile, side-emitting LEDs are described, where all light is efficiently emitted within a relatively narrow angle generally parallel to the surface of the light-generating active layer. The LEDs enable the creation of very thin backlights for backlighting an LCD. In one embodiment, the LED is a flip chip with the n and p electrodes on the same side of the LED, and the LED is mounted electrode-side down on a submount. A reflector is provided on the top surface of the LED so that light impinging on the reflector is reflected back toward the active layer and eventually exits through a side surface of the LED. A waveguide layer and/or one or more phosphors layers are deposed between the semiconductor layers and the reflector for increasing the side emission area for increased efficiency. Side-emitting LEDs with a thickness of between 0.2-0.4 mm can be created.

Abstract: In an LCD, a backlight having red, green, and blue LEDs is controlled to generate monochromatic light (e,g., blue) during a portion of a cycle, such as an image frame cycle. During another portion of the cycle, all the LEDs are illuminated to create white light. The color filter in the LCD panel contains, for each white pixel, a first color (e.g., red) subpixel filter, a second color (e.g., green) subpixel filter, and a clear subpixel area for passing white light and the monochromatic. The liquid crystal layer shutters are controlled to pass from 0-100% of the light for their associated subpixels to create a color image. With proper control of the shutters, any desired color of each white pixel can be achieved during the cycle. By converting one color filter to a clear area, the transmission efficiency of the display is greatly increased.

Abstract: A compact backlight system has a light-emitting panel (1) with a front wall (2), a rear wall (3) situated opposite thereto, a first edge surface (4) and, opposite thereto, a second edge surface (5) . A first light source (6) is associated with the first edge surface (4) which is light-transmitting. The light-emitting panel (1) widens over a widening section (100) from the first edge surface (4) in a direction towards the second edge surface (5), and the rear wall (3) is provided over the widening section (100) with a multiplicity of steps (13, 13?, . . . ) each having a surface (17) facing the front wall (2) which is substantially parallel to the front wall (2).

Abstract: A structure for providing a collimated light beam includes a light source configured to emit light having a first peak wavelength combined with a group of structures configured to direct at least a portion of light exiting the light source in a direction substantially perpendicular to a top surface of the light source and reflect another portion. In some embodiments, a wavelength converting element is positioned in a path of light emitted from the light source, the wavelength converting element configured to absorb at least a portion of the light having a first peak wavelength and emit light having a second peak wavelength. The group of structures may be formed over the wavelength converting element, such that the wavelength converting element is disposed between the group of structures and the light source.

Abstract: A light emitting device includes a light emitting element, an optical concentrator, such as a compound parabolic concentrator, a dichroic filter between the light emitting element and the optical concentrator and a wavelength converting material, such as a phosphor. The optical concentrator receives light from the light emitting element, via the dichroic filter, and emits the light from an exit surface, which is smaller than the entrance surface. The optical concentrator may be manufactured from a material with a high refractive index, such as sapphire. The wavelength converting material is, e.g., disposed over the exit surface. The radiance of the wavelength converting material is increased by pumping the wavelength converting material through a high index of refraction material and outputting the converted light into a low refractive index medium, such as air.

Abstract: A backlight for a display includes a plurality of illumination modules, each illumination module including a light source and a reflective member. A portion of the reflective member is disposed over the light source. A liquid crystal display panel is disposed over the plurality of illumination modules. The reflective member is configured such that a majority of light from the light source is directed parallel to the liquid crystal display panel, to provide uniform illumination of the liquid crystal display panel. In some embodiments, the light source is at least one semiconductor light emitting diode.

Abstract: Individual side-emitting LEDs are separately positioned in a waveguide, or mounted together on a flexible mount then positioned together in a waveguide. As a result, the gap between each LED and the waveguide can be small, which may improve coupling of light from the LED into the waveguide. Since the LEDs are separately connected to the waveguide, or mounted on a flexible mount, stress to individual LEDs resulting from changes in the shape of the waveguide is reduced.

Abstract: One or more LEDs are mounted within an LCD without the use of any printed circuit board (PCB), thus reducing the thickness of the LCD by about the thickness of the conventional PCB. In one embodiment, the LED and submount are mounted so that the submount is opposing the liquid crystal layer side of the LCD, so that the liquid crystal layers provide the mechanical support for the submount and LED die. The LED die (mounted on the submount) may be inserted into a cavity formed in the “top” surface of the light guide, and the top surface of the light guide is abutted against the liquid crystal layers. In such a configuration, the LED light source, including all supporting components, adds no thickness to the LCD. In another embodiment, on the “bottom” surface of the LCD opposing the LED die is an electrically switchable mirror that is either reflective or transparent. In its transparent state, the LED in the LCD may be used as a flash in a cell phone camera, while the LCD may be viewed to take the picture.

Abstract: An LED module includes an upper housing with in internal cavity and a lower housing. At least one light emitting diode is held in the LED module and emits light into the internal cavity, which is emitted through an output port in the upper housing. An optical structure, which may be disk or cylinder shaped may be mounted over the output port and light is emitted through the top surface and/or edge surface of the optical structure. The lower housing has a cylindrical external surface, which may be part of a fastener, such as screw threads, so that the LED module can be coupled to a heat sink, bracket or frame. The light emitting diode is thermally coupled to the lower housing, which may serve as a heat spreader. Additionally, a flange may be disposed between the upper housing and lower housing.

Abstract: A light emitting device is produced using one or more light emitting diodes within a light mixing cavity formed by surrounding sidewalls. The light emitting device includes a light adjustment member that is movable to alter the shape or color of the light produced by the light emitting device. For example, the light adjustment member may alter the exposure of the wavelength converting area to the light emitted that is emitted by the light emitting diode in the light mixing cavity. Alternatively, the height of a lens may be adjusted to change the width of the beam produced. Alternatively, a movable substrate with areas of different wavelength converting materials may adjustably cover the output port of the light mixing cavity to alter the color point of the light produced.

Abstract: A light emitting device is produced using a plurality of light emitting diodes within a light mixing cavity formed by surrounding sidewalls. The sidewalls may be integrally formed as part of a surrounding heat sink or alternatively may be an insert into a cavity within a heat sink. The reflective sidewalls may be coated with a diffusing material and/or covered with one or more phosphors. Multiple phosphors are located at different locations of the cavity, e.g., on the sidewalls, a window covering the output port, or on a reflector attached to the bottom of the cavity. The light emitting diodes may be positioned rotationally symmetrically around the optical axis on a board.

Abstract: A system for purifying a fluid uses ultra violet (UV) light to inactivate micro-organisms present in the fluid. The system has an arrangement of UV light emitters on perforated plates. The fluid, while passing through perforations in the perforated plates, is exposed to the UV light emitted by the UV light emitters. Micro-organisms present in the fluid pass very close to the UV light emitters. The UV light absorbed by the micro-organisms causes genetic damage and inactivation. The system has feedback units providing feedback about the physical properties of the fluid to a power unit supplying power to the UV light emitters. The power unit varies the amount of power supplied to the UV light emitters, based on the feedback.

Abstract: A projector includes a plurality of illumination modules. Each illumination module includes a light source, such as a semiconductor light emitting diode, and an optical element configured to receive light from the light source and collimate the light into a beam. Light from the illumination modules is provided to a liquid crystal display panel, then a projection lens. In some embodiments, secondary optics, such as an array of Fresnel lenses or a reflective polarizer, are disposed between the illumination modules and the liquid crystal display panel. In some embodiments, the liquid crystal display panel is a low temperature polysilicon liquid crystal display.