General Electric Company

Charles D Greskovich

Svante Prochazka

Dominic A Cusano

Curtis E Scott

Frank A DiBianca

Chester R O'Clair

James Anthony Brewer

Venkat Subramaniam Venkataramani

Steven Jude Duclos

Robert J Riedner

Alok Mani Srivastava

Robert Joseph Lyons

Richard J Charles

Robert Arthur Giddings

Michael F Gigliotti, Jr

William Paul Minnear

Veneta G Tsoukala

Holly Ann Comanzo

Frederic Joseph Klug

James Scott Vartuli

Wayne D Pasco

Joseph H Rosolowski

Erdogan O Gurmen

Michael John Lynch

George Eric Coxon

John A Palm

David Michael Hoffman

William Winder Beers

Dale M Brown

Marcus P Borom

Milivoj Konstantin Brun

Donald Thomas McGrath

James Walter LeBlanc

Michael Kent Cueman

Lewis Jones Thomas, Iii

Clifford Bueno

Mark E Duffy

Martin Kin-Fei Lee

Jack M Strok

Stephen Francis Bancheri

Robert C DeVries

Mary Sue Kaliszewski

Stephen L Dole

Casmir R Trzaskos

Douglas G Seredich

Joseph P Chernoch

Harry M Laska

Todd R Springer

Jean-Pierre J Georges

Steven Jude Ductos

Changlong Ning

Frank A DeBianca

An arc tube for a ceramic metal halide lamp includes a hollow first body member () that is tapered along a majority of its length to aid in removing the molded component from a pin during assembly. An open end () of the first body member has a constant diameter () allowing it to be joined to a constant diameter portion () of the second body member or end cap (). The mating constant diameter portions ensure that the hollow first body member can be monolithically joined with the end cap with a reduced level of seal voids.

Injection molded ceramic metal halide arc tube having non-tapered end and method of forming same

A ceramic discharge chamber for a lamp, according to an exemplary embodiment of the invention, comprises a first member which includes a leg portion and a transition portion, wherein the leg portion and the transition portion are integrally formed as one piece from a ceramic material, and a second member which includes a body portion, wherein the body portion is bonded to the transition portion of the first member. The ceramic discharge chamber can be formed by injection molding a ceramic material to form the first member, the first member forming a first portion of the ceramic discharge chamber; and bonding the first member to a second member which forms a second portion of the ceramic discharge chamber.

Ceramic discharge chamber for a discharge lamp

A conversion device for use in an imaging system is provided. The conversion device includes a first perforated plate portion forming a plurality of collimator channels separated by a plurality of thin collimator walls. A second perforated plate portion forming a plurality of scintillator channels separated by a plurality of thin scintillator walls is attached to the first perforated plate portion. A reflective coating is applied to the inside scintillator surface of the plurality of thin scintillator walls. A scintillator material is filled into the plurality of scintillator channels.

Monolithic structure for x-ray CT collimator

A system for use in oil drilling applications includes a scintillator material having a cubic garnet host and praseodymium distributed within the host. The scintillator material emits ultraviolet radiation in response to stimulating gamma ray radiation. A radiation detector optically coupled to the scintillator detects the emitted ultraviolet radiation. In a method for detecting oil, a radiation detector is optically coupled to a scintillator material having a cubic garnet host and praseodymium distributed within the host, wherein the praseodymium acts as an activator, and wherein the scintillator material emits ultraviolet radiation in response to stimulating gamma ray radiation. The detector and the scintillator material are lowered below the surface of the earth, and ultraviolet radiation emitted by the scintillator material in response to stimulating gamma ray radiation reflected by hydrogen bearing compounds indicating the presence of oil is detected by the detector.

Ultraviolet emitting scintillators for oil detection

A process for making an arc tube comprises the steps of sintering an arc tube composition to form the arc tube; annealing the arc tube in a vacuum; and sealing the arc tube with at least one electrode. Preferably, the arc tube annealed according to the present process is a ceramic arc tube. The annealing of the arc tubes in a vacuum preferably occurs at a temperature of between about 1000&deg; C. and 1500&deg; C.

Ceramic arc tube by annealing

The present invention provides terbium or lutetium garnet x ray scintillators activated with a rare earth metal ion, such as cerium, and treated by annealing in a controlled atmosphere comprising a predetermined amount of oxygen for a predetermined time and temperature to reduce radiation damage that would otherwise occur when the scintillator material is exposed to high energy radiation, such as the type of radiation required to use the scintillator for medical radiographic imaging and the like. In an embodiment, a single crystal or a polycrystalline scintillator comprising the general formula (Tb Lu Ce ) Al O (where 0<&times;&lE;0.5, and y is in the range from about 0.0005 to about 0.2, and annealed at 1400&deg; C. to 1500&deg; C. in a controlled atmosphere comprising 1&times;10 to 0.22 atm oxygen shows an increased resistance to radiation damage.

Terbium or lutetium containing garnet scintillators having increased resistance to radiation damage

A ceramic discharge chamber for a lamp, according to an exemplary embodiment of the invention, comprises a first member which includes a leg portion and a transition portion, wherein the leg portion and the transition portion are integrally formed as one piece from a ceramic material, and a second member which includes a body portion, wherein the body portion is bonded to the transition portion of the first member. The ceramic discharge chamber can be formed by injection molding a ceramic material to form the first member, the first member forming a first portion of the ceramic discharge chamber; and bonding the first member to a second member which forms a second portion of the ceramic discharge chamber. The members which form the ceramic discharge chamber can greatly facilitate assembly of the discharge chamber, because the discharge chamber can be constructed with only one or two bonds between the members. The reduction in the number of bonds has the advantages of expediting assembly of the discharge chamber, reducing the number of potential bond defects during manufacturing, and reducing the possibility of breakage of the discharge chamber at a bond region during handling. One or more of the members may also include a radially directed flange which allows the members to be precisely aligned during assembly to improve the quality of the lamp.

A radiation detector includes: a scintillator which produces UV photons in response to receiving radiation from a radiation producing source; and, a wide bandgap semiconductor device sensitive to the UV photons produced by the scintillator. The semiconductor device produces an electric signal as a function of the amount of UV photons incident thereon. Preferably, the electric signal is then measure, recorded and/or otherwise analyzed.

SiC photodiode detectors for radiation detection applications

A high transmittance polycrystalline alumina arc tube for a metal halide discharge lamp is formed by treating an alumina arc tube material having a few percent of closed porosity in a two step process, which provides a high-transmittance arc tube. An initially porous arc tube is formed by extruding or die pressing individual components of the tube from a mixture which includes powdered alumina, assembling the components into an arc tube body, and then partially sintering the components to seal them together. The two step process includes hot isostatic pressing of the partially sintered arc tube and then chemically polishing the surface of the tube. The first, pressing step involves heating the alumina arc tube in an inert atmosphere, such as argon, at a temperature of 1600 to 1900&deg; C. and a pressure of about 700 to 2100 kg/sq.cm. for from about one to three hours. This reduces porosity in the crystalline structure. In the second step, the surface of the tube is immersed in a flux comprising a molten alkali metal borate at moderately elevated temperatures, or coated with a flux material which is heated to form the flux, to remove surface imperfections. The finished arc tube has transmittance values which approach those of single crystal sapphire arc tubes.

High transmittance alumina for ceramic metal halide lamps

An arc discharge vessel having electrodes disposed therein, a fill within the discharge vessel wherein the arc discharge vessel is comprised of alumina including the following dopants in parts per million: 50&lE;MgO&lE;1500; 100&lE;HFO &lE;1500; 0&lE;ZrO &lE;700; 0&lE;Y O &lE;300; 0&lE;Sc O &lE;1000; 0&lE;Dy O &lE;1000; 0&lE;Tb O &lE;1000; with the proviso that at least 5 ppm Y O , Sc O , Dy O , Tb O , or mixtures thereof is included.

High pressure discharge lamp

A method of preparing and testing an array of ceramics for optical properties, comprising: providing a host material that is capable of being made optically transparent or translucent upon sintering; forming the host material into an array of pixels attached to a base plate; doping the host material; reacting the host material and the dopant, to form an array of products; and testing the products for optical properties.

Combinatorial method foe development of optical ceramics

A process for converting a polycrystalline ceramic material to a single crystal material includes the steps of doping at least a first portion of the polycrystalline ceramic material with a conversion-enhancing dopant having a &plus;6 valence state in the unfired ceramic material and heating the polycrystalline ceramic material to convert at least a second portion of the polycrystalline ceramic material to a single crystal ceramic material. Preferably, the ceramic material is alumina and the conversion-enhancing dopant is molybdenum or tungsten.

Conversion of polycrystalline alumina to single crystal sapphire using molybdenum doping

A Y(P,V)O :Eu red emitting phosphor is doped with at least one of a trivalent rare earth ion excluding Eu and a divalent metal ion to improve the lumen maintenance of the phosphor. The preferred material is the Y(P,V)O :Eu phosphor doped with trivalent Tb ions and divalent Mg ions.

YMO4:Eu,L phoshpor with improved lumen maintenance

The invention relates to a method of forming a composite article comprising the steps of forming a plurality of green ceramic elements, wherein the green ceramic elements are arranged side by side, and the green ceramic elements are spaced from each other by gaps; filling the gaps with a second material; and sintering the green ceramic elements with the second material to form the composite article. The second material, after being sintered, acts as a reflector layer to prevent substantially all light in one of the sintered ceramic elements from reaching an adjacent sintered ceramic element. The step of filling the gaps may be carried out by forming a slurry containing the second material in powder form and immersing the green ceramic elements in the slurry. The process of cosintering the green ceramic elements with the reflector composition provides improved dimensional control during sintering and reduces processing costs.

Composite ceramic article and method of making

Growing community of inventors

Schenectady, NY, United States of America

Charles D Greskovich