Abstract: A one-dimensional array of light emitting diodes (LEDs) is configured to place the LEDs in close proximity to each other, e.g., 150 ?m or less and to place at least one side of the LEDs in close proximity to the edge of the substrate, e.g., 150 ?m or less. With the LEDs close to the edge of the substrate, multiple one-dimensional arrays may be joined together, side by side, to form a two-dimensional array with the LEDs from adjacent one-dimensional arrays positioned close together. By minimizing the gaps between the LEDs on the same one-dimensional arrays and adjacent one-dimensional arrays, the luminance of the device is improved making the device suitable for high radiance applications. Moreover, using a number of one-dimensional arrays to form a larger two-dimensional array increases yield relative to conventional monolithic two-dimensional arrays.

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: For mixing different light colors from different LEDs or energized phosphors, an elongated mixing tunnel is used having a reflective inner surface. LEDs of different colors are optically coupled along the length of the mixing tunnel and at a first end of the tunnel. Light coupled along the length of the tunnel is reflected by an angled dichroic mirror that selectively reflects the incoming color light towards a single output port of the mixing tunnel. The dichroic mirror passes all other colors of light being transmitted towards the output port of the tunnel. Two, three, or more colors of LEDs can be used. Efficient and compact ways to energize phosphors are also described. Other optical techniques are also described.

Abstract: High power white light LEDs are distributed within a thin reflective cavity. The cavity depth may be less than 3 cm and, in one embodiment, is about 1 cm. A light output surface of the cavity is a flat reflector with many small openings. A small plastic lens is positioned over each opening for causing the light emitted from each opening to form a cone of light between approximately 50-75 degrees. Alternatively, each hole may be shaped to be a truncated cone to control the dispersion. The light emitted by the LEDs is mixed in the cavity by reflecting off all six reflective walls of the cavity. The light will ultimately escape through the many holes, forming a relatively uniform pattern of light on a surface to be illuminated by the luminaire.

Abstract: Low profile, side-emitting LEDs are described. The LEDs are used in very thin backlights for backlighting an LCD. In one embodiment, the backlight comprises a solid transparent waveguide with at least one opening in the waveguide containing an LED proximate to one edge. To smooth out a clover-shaped or batwing brightness profile inherently generated by a rectangular side-emitting LED within a smooth-sided rectangular opening in the waveguide, depending on the orientation of the LED, the sidewalls of the opening are made to have varying angles along the length of each sidewall to vary the refraction angle of light along the sidewall. Additionally, if a plurality of LEDs are used in the backlight, the orientations of the openings alternate to create a more uniform brightness profile in the waveguide.

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: Low profile, side-emitting LEDs are described that generate white light, where all light is 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 emits blue light and is a flip chip with the n and p electrodes on the same side of the LED. Separately from the LED, a transparent wafer has deposited on it a red and green phosphor layer. The phosphor color temperature emission is tested, and the color temperatures vs. positions along the wafer are mapped. A reflector is formed over the transparent wafer. The transparent wafer is singulated, and the phosphor/window dice are matched with the blue LEDs to achieve a target white light color temperature. The phosphor/window is then affixed to the LED.

Abstract: Very thin flash modules for cameras are described that do not appear as a point source of light to the illuminated subject. Therefore, the flash is less objectionable to the subject. In one embodiment, the light emitting surface area is about 5 mm×10 mm. Low profile, side-emitting LEDs optically coupled to solid light guides enable the flash module to be thinner than 2 mm. The flash module may also be continuously energized for video recording. The module is particularly useful for cell phone cameras and other thin cameras.

Abstract: A solid state illumination device includes a semiconductor light emitter mounted on a base and surrounded by sidewalls, e.g., in a circular, elliptical, triangular, rectangular or other appropriate arrangement, to define a chamber. A top element, which may be reflective, may be coupled to the sidewalls to further define the chamber. The light produced by the semiconductor light emitter is emitted through the sidewalls of the chamber. The sidewalls and/or top element may include wavelength converting material, for example, as a plurality of dots on the surfaces. An adjustable wavelength converting element may be used within the chamber, with the adjustable wavelength converting element being configured to adjust the surface area that is exposed to the light emitted by the semiconductor light emitter in the chamber to alter an optical property of the chamber.

Abstract: High power white light LEDs are distributed within a thin reflective cavity. The cavity depth may be less than 3 cm and, in one embodiment, is about 1 cm. A light output surface of the cavity is a flat reflector with many small openings. A small plastic lens is positioned over each opening for causing the light emitted from each opening to form a cone of light between approximately 50-75 degrees. Alternatively, each hole may be shaped to be a truncated cone to control the dispersion. The light emitted by the LEDs is mixed in the cavity by reflecting off all six reflective walls of the cavity. The light will ultimately escape through the many holes, forming a relatively uniform pattern of light on a surface to be illuminated by the luminaire.

Abstract: Various embodiments of corner-coupled backlights are described, where one or more white light LEDs are optically coupled to a truncated corner edge of a solid rectangular light guide backlight. The one or more LEDs are mounted in a small reflective cavity, whose output opening is coupled to the truncated corner of the light guide. The reflective cavity provides a more uniform light distribution at a wide variety of angles to the face of the truncated corner to better distribute light throughout the entire light guide volume. To enable a thinner light guide, the LED die is positioned in the reflective cavity so that the major light emitting surface of the LED is parallel to the top surface of the light guide. The reflective cavity reflects the upward LED light toward the edge of the light guide.

Abstract: One or more LED dice are mounted on a support structure. The support structure may be a submount with the LED dice already electrically connected to leads on the submount. A mold has indentations in it corresponding to the positions of the LED dice on the support structure. The indentations are filled with a liquid optically transparent material, such as silicone, which when cured forms a lens material. The shape of the indentations will be the shape of the lens. The mold and the LED dice/support structure are brought together so that each LED die resides within the liquid silicone in an associated indentation. The mold is then heated to cure (harden) the silicone. The mold and the support structure are then separated, leaving a complete silicone lens over each LED die. This over molding process may be repeated with different molds to create concentric shells of lenses.

Abstract: An illumination source includes at least one light emitting diode, e.g., in array of LEDs that produce short wavelength light. One or more wavelength converting elements, such as phosphor elements, convert at least a portion of the short wavelength light from the LED(s) to longer wavelengths, such as Red and Green. A dichroic element positioned between the LED(s) and the wavelength converting element(s) transmits the light from the LED(s) and reflects the longer wavelengths from the wavelength converting element(s). A color selection panel selects the colors of light to be produced by the illumination device and to be recycled for another opportunity to be converted by the wavelength converting element(s) or to be reflected by the dichroic element. The color selection panel may operate in one or both of the spatial domain and the temporal domain.

Abstract: A multi-primary light emitting diode system includes the use of a polarization based dichroic element to combine light from different color channels. At least one of the color channels includes two light emitting diodes that produce light with a different range of wavelengths. The use of the polarization based dichroic element permits overlapping spectra from different color channels to be combined without loss. Accordingly, the brightness of the system is improved relative to conventional systems in which losses occur when combining overlapping spectra from different channels.

Abstract: A uniform high brightness light source is provided using a plurality of light emitting diode (LED) chips with slightly different pump wavelengths with a wavelength converting element that includes at least two different wavelength converting materials that convert the light to different colors of light. The intensity of the light produced by the LED chips may be varied to provide a tunable CCT white point. The wavelength converting element may be, e.g., a stack or mixture of phosphor or luminescent ceramics. Moreover, the manufacturing process of the light source is simplified because the LED chips are all manufactured using the same technology eliminating the need to manufacture different types of chips.

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: 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: The invention provides a light-emitting device and a method of illumination. The light-emitting device includes one or more semiconductor layers, a reflective bottom surface, and a top surface coupled to semiconductor layer. The semiconductor layers include an active region where a primary light is generated. The relative position of the top surface, the reflective bottom surface and the active region is adjusted to substantially transmit the primary light through the sides of the light-emitting device.

Abstract: Lenses and certain fabrication techniques are described. A wide-emitting lens refracts light emitted by an LED die to cause a peak intensity to occur within 50-80 degrees off the center axis and an intensity along the center axis to be between 5% and 33% of the peak intensity. The lens is particularly useful in a LCD backlighting application. In one embodiment, the lens is affixed to the backplane on which the LED die is mounted and surrounds the LED die. The lens has a hollow portion that forms an air gap between the LED die and the lens, where the light is bent towards the sides both at the air gap interface and the outer lens surface interface. The lens may be a secondary lens surrounding an interior lens molded directly over the LED die.

Abstract: One or more LED dice are mounted on a support structure. The support structure may be a submount with the LED dice already electrically connected to leads on the submount. A mold has indentations in it corresponding to the positions of the LED dice on the support structure. The indentations are filled with a liquid optically transparent material, such as silicone, which when cured forms a lens material. The shape of the indentations will be the shape of the lens. The mold and the LED dice/support structure are brought together so that each LED die resides within the liquid silicone in an associated indentation. The mold is then heated to cure (harden) the silicone. The mold and the support structure are then separated, leaving a complete silicone lens over each LED die. This over molding process may be repeated with different molds to create concentric shells of lenses.