Osram Sylvania Inc.

Gte Laboratories Incorporated

Osram Opto Semiconductors Gmbh

Valenite, Inc.

Gte Products Corporation

George C Wei

Arlene Hecker

John Walsh

Walter Peter Lapatovich

Madis Raukas

William H Rhodes

Yi Zheng

David Alan Goodman

Edmund M Dunn

Harry S Mackel

Stefan Lange

Dieter Lang

Stefan Juengst

Jerry Martin Kramer

Helmar Adler

Richard C Marlor

Roland Huettinger

Nathan M Zink

Shinhoo Kang

Christopher A Tarry

George A Fryburg

Frank Jermann

Tim Fiedler

Krister Bergenek

John H Selverian

Peter Niedermeier

Adam Scotch

Kailash C Mishra

Joanne M Browne

Paul H Ingalls

Steven Mackel

Rodrique G Thibodeau

Kang, Shinhoo

Karl Krister Bergenek

Adam M Scotch

John Selverian

A radiation-emitting component comprising a ceramic material, comprising a garnet having the composition represented by the formula A3-xB5O12:Dx and a barium-containing oxide. In the garnet A3-xB5O12:Dx, A is selected from lutetium, yttrium, gadolinium, terbium, scandium, another rare earth metal or mixtures thereof. B is selected from aluminum, scandium, gallium, indium, boron or mixtures thereof. D is at least one dopant selected from chromium, manganese and rare earth metals, particularly cerium, praseodymium or gadolinium. The dopant is present with x is 0&#x2264;x&#x2264;2.

Garnet material, method for its manufacturing and radiation-emitting component comprising the garnet material

A material, comprising a garnet having the composition represented by the formula ABO:Dand a barium-containing oxide. In the garnet ABO:D, A is selected from lutetium, yttrium, gadolinium, terbium, scandium, another rare earth metal or mixtures thereof. B is selected from aluminum, scandium, gallium, indium, boron or mixtures thereof. D is at least one dopant selected from chromium, manganese and rare earth metals, particularly cerium, praseodymium or gadolinium. The dopant is present with x is 0&#x2266;x&#x2266;2.

There is herein described an LED light source comprising an LED and a ceramic wavelength converter positioned to receive at least a portion of the light emitted by said LED, said ceramic wavelength converter converting at least a portion of the light emitted by said LED into light of a different wavelength, said ceramic wavelength converter comprising a chlorosilicate phosphor and having a density at least about 90% of theoretical density. The chlorosilicate phosphor is preferably a green-emitting CaMg(SiO)Cl:Euphosphor.

Ceramic wavelength converter and LED light source containing same

An opaque zone in the polycrystalline (PCA) discharge vessel of a high intensity discharge lamp may be made by creating residual pores in predetermined regions of the final-sintered discharge vessel. The control over the placement of the opaque zone is achieved by forming a carbonaceous residue in a specific region of the discharge vessel prior to final sintering. During sintering, the carbonaceous material causes residual porosity in the sintered PCA. The higher emissivity of the opaque PCA provides localized cooling in order to provide more control over the condensate behavior in the discharge vessel.

Ceramic discharge vessel having an opaque zone and method of making same

Polycrystalline alumina (PCA) that has been doped with magnesium oxide is converted to sapphire by additionally doping the PCA with boron oxide and sintering to induce abnormal grain growth. The boron oxide may be added to an already formed green PCA ceramic shape by applying an aqueous boric acid solution to the green ceramic and heating the green ceramic in air to convert the boric acid to boron oxide.

Method of converting PCA to sapphire and converted article

An more efficient or higher luminance LED assembly may be formed from a high power LED chip having a first surface, and a second surface, the first surface being mounted to a substrate; the second surface being in intimate thermal contact with a light transmissive heat sink having a thermal conductivity greater than 30 watts per meter-Kelvin. The LED chip is otherwise in electrical contact with at least a first electrical connection and a second electrical connection for powering the LED chip. Providing light transmissive heat sink can double the heat conduction from the LED dies thereby increasing life, or efficiency or luminance or a balance of the three.

LED with light transmissive heat sink

The present invention is a ceramic discharge vessel for use in high-intensity-discharge (HID) lamps. The discharge vessel has a ceramic body and at least one seal region comprised of an aluminum oxynitride material. The seal region further has a surface layer for contacting a frit material wherein the surface layer is less reactive than the aluminum oxynitride material with respect to the molten frit during sealing. Preferably, the surface layer has a lower nitrogen content than the aluminum oxynitride material. The less reactive surface acts to minimize the formation of bubbles in the sealing frit during the sealing operation.

Method of treating a ceramic discharge vessel

There is described a brazing alloy having a first component comprising a source of molybdenum and a source of aluminum and a second component comprising boron, wherein a weight ratio of said second component to said first component is not greater than 1:20. The addition of boron results a substantially lower melting point than alloys employing molybdenum and aluminum alone. It is suitable for use in discharge vessels having a hollow bodies selected from the group of monocrystalline alumina, polycrystalline alumina and aluminum nitride; metallic electrode holders fitted into ends of the hollow body; and sealed thereto by a braze.

Brazing alloy and ceramic discharge lamp employing same

A discharge lamp having a visual-change timer is described. The visual-change timer is comprised of a ceramic material that provides an indication of the cumulative operating time of the lamp. The visual-change timer is expected be a help to consumers in avoiding unnecessary, premature, and costly lamp replacement and a help to lamp manufacturers in verifying the validity of warranty claims for replacement lamps.

Discharge lamp having a visual-change timer

The present invention uses a post-sinter-HIP anneal to increase the total transmittance of ceramic discharge vessels comprised of a submicron-grained alumina doped with MgO. After the anneal, the submicron-grained alumina discharge vessels have high values of both total and in-line transmittance, and are thus suitable for use in focused-beam, short-arc lamps. In particular, the total transmittance of the discharge vessel is increased to greater than 92% in the wavelength range from about 400 nm to about 700 nm.

High total transmittance alumina discharge vessels having submicron grain size

The present method uses a methane-containing nitrogen gas sintering atmosphere to sinter aluminum nitride (AlN) to a high transmittance. The methane gas replaces the solid carbon charge material used in prior art sintering methods as the source of gaseous carbon. The amount of carbon in the methane-containing nitrogen gas is easily controlled by varying the partial pressure of methane in the nitrogen gas. In addition, the methane flow is stopped prior to the end of the sintering cycle to prevent darkening of the sintered part.

Method of sintering AIN under a methane-containing nitrogen atmosphere

There is described a sealing composition for sealing aluminum nitride and aluminum oxynitride ceramics comprising: a mixture of SiO, at least one other metal oxide, and a silicon additive comprising at least one of silicon metal or a silicide. The silicon additive acts to suppress the formation of nitrogen bubbles during the sealing of articles comprised of aluminum nitride or aluminum oxynitride ceramics, e.g., as in the case of a ceramic discharge vessel for a high intensity discharge lamp.

Sealing composition for sealing aluminum nitride and aluminum oxynitride ceramics

Aluminum nitride arc discharge vessels having a high total transmittance may be made by annealing the as-sintered AlN vessel in a nitrogen atmosphere, preferably at a temperature of at least about 1850&#xb0; C. and for a time of at least about 50 hours. The annealing increases the total transmittance of the vessel to greater than 92% in the wavelength region from about 400 nm to about 700 nm. The annealed AlN discharge vessels are useful for lamp applications, such as metal halide lamps, and offer an improved durability and life over polycrystalline alumina (PCA).

Aluminum nitride arc discharge vessel having high total transmittance and method of making same

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Weston, MA, United States of America

George C Wei