Philips Electronics North America Corporation

U.S. Philips Corporation

Vivek Mehrotra

Susan McGee

Thomas F McGee

Babar Ali Khan

Hemant S Betrabet

Edward Young

Jeroen Langevoort

Shri Sridhar

Gert W Bruning

Jerry Martin Kramer

Ronald D Pinker

Nicolaas Bernardus Roozen

David A Cammack

Jose Azevedo

David R Woodward

Thomas O Leyh

Juan A Sabate

A lamp electronic ballast with a piezoelectric cooling fan. Use of ballast-driven lamps is limited in some lighting applications by thermal considerations. For example, the problem of heat removal from compact fluorescent lamps with integrated ballasts has limited their use. Similarly, the use of ballast-driven fluorescent lighting in high hat and other closed luminaire applications has been limited by thermal considerations. Thermal management of ballasts for such thermally sensitive applications is provided by a piezoelectric fan integrated with the ballast. The power to drive the fan may be obtained from the same AC line input that supplies the ballast, or from an AC ripple voltage present at the output of a rectifier in the ballast, or from the output of the ballast to the lamp, or from any suitable circuit location in the ballast. The fan maybe a membrane-type spot-cooler comprising a thin membrane carried by a frame mounted adjacent a hot spot. The membrane has one or more holes in it and is vibrated about a central plane by suitably spaced piezoelectric elements attached to the membrane.

Lamp electronic ballast with a piezoelectric cooling fan

Anodized aluminum anode and cathode foils are interleaved in a stack separated by spacers saturated with electrolyte in an enclosure. The anode foils and cathode foils have tabs which protrude from the housing and are cold welded to leads outside the housing, where they are not exposed to electrolyte. This permits using copper leads, which can be soldered to traces on a printed circuit board. A flat capacitor can be fixed underneath a PCB or even used as the substrate for a circuit, resulting in high volume efficiencies and the possibility of using it as a heat sink for other components.

Flat electrolytic capacitor

Novel emitter materials, electrode assemblies amd lamps comprising the same are provided in which, in accordance with the invention, novel electrodes are provided having a lamp electrode structure, preferably including a hollow ferrule for sealing in a lamp to permit evacuation; an emitter material of the invention on at least one surface thereof, preferably on a protrusion attached to the hollow ferrule; a thermal isolator, preferably in the form of a low thermal conductivity wire or an incised or cut-out portion of the hollow ferrule body, for thermally isolating the protrusion from the ferrule to maintain a sufficiently high temperature for thermionic emission, and further comprising an emitter material requiring no in-lamp processing. The emitter materials are a mixed oxide of Ba, Sr and mixtures thereof with one or more of the metals from the series comprising Ta, Ti, Zr, Sc, Y, and La, are preferably selected from the group consisting of Ba.sub.4 Ta.sub.2 O.sub.9, Ba.sub.5 Ta.sub.4 O.sub.15, BaY.sub.2 O.sub.4, BaCeO.sub.3, Ba.sub.x Sr.sub.1-x Y.sub.2 O.sub.4, Ba.sub.2 TiO.sub.4, BaZrO.sub.3, Ba.sub.x Sr.sub.1-x TiO.sub.3, and Ba.sub.x Sr.sub.1-x ZrO.sub.3, wherein x ranges from a value of 0 to 1, and are most preferably one or more mixed oxides selected from the group consisting of Ba.sub.4 Ta.sub.2 O.sub.9, BaY.sub.2 O.sub.4, BaCeO.sub.3, Ba.sub.0.5 Sr.sub.0.5 Y.sub.2 O.sub.4, Ba.sub.0.75 Sr.sub.0.25 Y.sub.2 O.sub.4, Ba.sub.2 TiO.sub.4, BaZrO.sub.3, Ba.sub.0.5 Sr.sub.0.5 TiO.sub.3, and Ba.sub.0.5 Sr.sub.0.5 ZrO.sub.3.

Hollow electrodes for low pressure discharge lamps, particularly narrow

To improve performance, reliability and lifetime of a plasma-containing electro-optic display device, at least the cathode electrodes have hollows or wells within which plasma discharge occurs. This reduces the tendency of the electrode material to be sputter deposited on the walls of the device. In addition, cathode emission is improved by incorporating emitter materials into the electrodes, either by alloying or by surface coatings.

Hollow cathodes for plasma-containing display devices and method of

Novel emitter materials, electrode assemblies amd lamps comprisinfg the same are provided in which, in accordance with the invention, novel electrodes are provided having a lamp electrode structure, preferably including a hollow ferrule for sealing in a lamp to permit evacuation; an emitter material of the invention on at least one surface thereof, preferably on a protrusion attached to the hollow ferrule; a thermal isolator, preferably in the form of a low thermal conductivity wire or an incised or cut-out portion of the hollow ferrule body, for thermally isolating the protrusion from the ferrule to maintain a sufficiently high temperature for thermionic emission, and further comprising an emitter material requiring no in-lamp processing. The emitter materials are a mixed oxide of Ba, Sr and mixtures thereof with one or more of the metals from the series comprising Ta, Ti, Zr, Sc, Y, and La, are preferably selected from the group consisting of Ba.sub.4 Ta.sub.2 O.sub.9, Ba.sub.5 Ta.sub.4 O.sub.15, BaY.sub.2 O.sub.4, BaCeO.sub.3, Ba.sub.x Sr.sub.1-x Y.sub.2 O.sub.4, Ba.sub.2 TiO.sub.4, BaZrO.sub.3, Ba.sub.x Sr.sub.1-x TiO.sub.3, and Ba.sub.x Sr.sub.1-x ZrO.sub.3, wherein x ranges from a value of 0 to 1, and are most preferably one or more mixed oxides selected from the group consisting of Ba.sub.4 Ta.sub.2 O.sub.9, BaY.sub.2 O.sub.4, BaCeO.sub.3, Ba.sub.0.5 Sr.sub.0.5 Y.sub.2 O.sub.4, Ba.sub.0.75 Sr.sub.0.25 Y.sub.2 O.sub.4, Ba.sub.2 TiO.sub.4, BaZrO.sub.3, Ba.sub.0.5 Sr.sub.0.5 TiO.sub.3, and Ba.sub.0.5 Sr.sub.0.5 ZrO.sub.3.

A high pressure gas discharge lamp and the method of making same utilizing integrated circuit fabrication techniques. The lamp is manufactured from heat and pressure resistant planar substrates in which cavities are etched, by integrated circuit manufacturing techniques, so as to provide a cavity forming the gas discharge tube. Electrodes are deposited in the cavity. The cavity is filled with gas discharge materials such as mercury vapor, sodium vapor or metal halide. The substrates are bonded together and channels may be etched in the substrate so as to provide a means for connection to the electrodes. Lamps having ignition enhancing and hot restrike features, as well as single-sided electrodes, are disclosed.

Gas discharge lamps fabricated by micromachined transparent substrates

Hollow cathodes with an I-beam or C-beam cross section for a plasma

Composite sintered electrodes with improved properties that make them suitable for use in a variety of lamp types, are provided which comprise a refractory metal and a substantial amount of a refractory emitter oxide, either single layer or multiple layer, the composites having been subjected to sintering at an elevated temperature effective to form a composite electrode having a density of at least 85%, preferably in the presence of a sintering activator, such as for example, Ni, or mixture thereof with a sintering aid such as, for example, Li.sub.2 O.

Multiple layer composite electrodes for discharge lamps

Lamps that include composite sintered electrodes with improved properties that make them suitable for use in a variety of lamp types, are provided by a method for producing electrodes which comprise a refractory metal and a refractory emitter oxide, either single layer or multiple layer, the composites having been subjected to sintering at an elevated temperature effective to form a composite electrode having a density of at least 85%, preferably in the presence of a sintering activator, such as for example, Ni, or mixture thereof with a sintering aid such as, for example Li.sub.2 O.

Multiple layer composite electrodes for discharge lamps and low

The present invention is directed to new electrode structures for use in fluorescent lamps in which a tungsten base structure is provided with electron emissive materials including one or more of barium titanate, barium zirconate, barium strontium zirconate, barium cerium oxide, barium tantalate, and barium strontium yittrium oxide. Amounts of MgO may be added to improve or change emitter properties. A composite electrode structure can be formed by way of coating a tungsten coil with a slurry of this material, or providing powdered mixtures of both the electron emissive material and tungsten material and sintering this powdered material into a high density composite electrode structure.

Growing community of inventors

Rye Brook, NY, United States of America

Vivek Mehrotra