Xicato, Inc.

Philips Lumileds Lighting Company LLC

Koninklijke Philips Corporation N.V.

Mark A Pugh

Gerard Harbers

Peter K Tseng

Menne T De Roos

John S Yriberri

Serge J Bierhuizen

Michael Ragan Krames

John Edward Epler

Oleg Borisovich Shchekin

Gerd O Mueller

Regina B Mueller-Mach

Robert Scott West

Menne T Deroos

Serge Joël Bierhuizen

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.

Solid state illumination device

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.

Illumination device with light emitting diodes

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.

Illumination device with light emitting diodes and movable light adjustment member

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.

Modular solid state lighting device

Illumination device with light emitting diodes and moveable light adjustment member

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.

Color tunable light source

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.

Low profile side emitting LED with window layer and phosphor layer

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.

Backlight using LED parallel to light guide surface

The invention provides an illumination system and a method for illumination. The illumination system includes one or more light sources that produce a primary light, a light-mixing zone that homogenizes the primary light, a wavelength-converting layer that converts the primary light to a secondary light, and a light-transmitting zone that receives the secondary light and transmits the secondary light to, for example, a Liquid Crystal Display (LCD).

Illumination system using phosphor remote from light source

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.

White LED for backlight with phosphor plates

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.

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Los Gatos, CA, United States of America

Mark A Pugh