Electrode Composition Patents (Class 313/633)
  • Patent number: 6844678
    Abstract: A short arc discharge lamp in which the wear on the cathode tip area is suppressed, in which moreover in the arc discharge only little polarization occurs and flickering in the arc discharge occurs only rarely, and thus, a reduction of illuminance or flickering on the light irradiation surface of a device or the like in which the short arc discharge lamp has been installed is prevented. Furthermore, a short arc discharge lamp is devised in which the radiance is hardly impaired and stable light emission is enabled, even when it is operated over a long time. To obtain these advantages, a short arc discharge lamp which has an essentially spherical arc tube in which there are a cathode and an anode opposite one another, is provided with a cathode in which the cathode tip area has a crystal structure formed of several crystals which, as compared to the crystal size in the back end area of the cathode, are coarsened, and in which the emissive material contained in the cathode tip area is less than or equal to 0.
    Type: Grant
    Filed: September 26, 2001
    Date of Patent: January 18, 2005
    Assignee: Ushiodenki Kabushiki Kaisha
    Inventors: Tuneo Okanuma, Keisuke Okubo
  • Patent number: 6815892
    Abstract: In a discharge lamp which has a silica glass discharge vessel with an arc tube portion and hermetically sealed portions in which in the hermetically sealed portions of this discharge vessel metal foils are installed and hermetically sealed areas are formed, in accordance with the invention has a high endurance of the sealing action in the hermetically sealed areas and thus a long service life is obtained by a coating layer being formed on at least one side of the respective metal foil. The coating layer is formed from at least one metal oxide which is selected from titanium oxide, lanthanum oxide, tantalum oxide, zirconium dioxide which can contain yttrium oxide, and from hafnium dioxide which can contain yttrium oxide. Furthermore, the metal oxide which forms the coating layer is advantageously crystalline, and moreover, can be formed over a base layer which is made of aluminum oxide or yttrium oxide.
    Type: Grant
    Filed: September 10, 2002
    Date of Patent: November 9, 2004
    Assignee: Ushiodenki Kabushiki Kaisha
    Inventors: Yukihiro Morimoto, Katsumi Sugaya
  • Publication number: 20040217705
    Abstract: There is provided an improved high-pressure discharge lamp which includes an arc tube encapsulating a halogen, and a pair of tungsten electrodes disposed in the arc tube. The oxygen content in the tungsten electrodes is not more than 15 ppm, while the amount of the encapsulated halogen lies in the range of 1×10−7 to 1×10−2 &mgr;mol/mm3.
    Type: Application
    Filed: April 29, 2004
    Publication date: November 4, 2004
    Applicant: Phoenix Electric Co., Ltd.
    Inventor: Hiroshi Takahashi
  • Patent number: 6809478
    Abstract: A metal halide lamp for an automobile headlight is provided, which includes an arc tube in which a pair of tungsten electrodes are provided at both ends and a metal halide as a main component of a luminescent material and xenon gas as a buffer gas are sealed, wherein the tungsten electrodes contain not more than 0.4 wt % of thorium oxide, the metal halide contains scandium iodide, and a pressure of the xenon sealed in the arc tube is at least 0.4 MPa. This makes it possible to provide a long-life metal halide lamp for an automobile headlight that can achieve a further improved lumen maintenance factor and other life characteristics during 2000 hours or more of lighting.
    Type: Grant
    Filed: November 25, 2002
    Date of Patent: October 26, 2004
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masato Yoshida, Hideaki Kiryu
  • Publication number: 20040178732
    Abstract: An assembly for lamp construction, comprising a solid W component (10) and at least one film (9) having two contact faces, comprising a metallic molybdenum base body and a coating, which is applied at least in part to said base body and which comprises ruthenium or rhenium alone or as an alloy in the region of the first contact face, which produces the contact with the W component, whereas the second contact face is not coated and is intended to be in contact with glass.
    Type: Application
    Filed: February 27, 2004
    Publication date: September 16, 2004
    Applicant: PATENT-TREUHAND-GESELLSCHAFT FUR ELEKTRISCHE GLUHLAMPEN mbH
    Inventor: Bodo Mittler
  • Publication number: 20040169476
    Abstract: The invention relates to a mercury short-arched-high pressure discharge lamp (1) which operates with direct-current, comprising a discharge vessel (2) having two necks (4) arranged in a diametrical manner opposite each other, wherein an anode (26) and a cathode (7), made respectively from tungsten, are melted in a gas-tight manner and said vessel is filled with mercury and at least one inert gas. According to the invention, the material of the cathode tip (11) contains, in addition to the tungsten, lanthanum oxide La2O3 and the mercury content of the filling in the discharging vessel volume is at least 1 mg/cm3 and at the most 6 mg/cm3.
    Type: Application
    Filed: December 11, 2003
    Publication date: September 2, 2004
    Inventors: Dietmar Ehrlichmann, Lars Menzel
  • Patent number: 6784618
    Abstract: The invention concerns faceplate, more particularly for plasma display, comprising a substrate on which is provided at least one electrode, made of conductive material consisting of a metal alloy based on aluminium and/or zinc having a melting point higher than 700° C.; the electrode is designed to be coated with a dielectric layer. Thus, the harmful effects derived from reactions of the electrode materials with those of the dielectric layer are limited, in particular when said layer is being cured.
    Type: Grant
    Filed: September 22, 2000
    Date of Patent: August 31, 2004
    Assignee: Syngenta Participations AG
    Inventors: Agide Moi, Luc Berthier, Jean-Pierre Creusot
  • Patent number: 6774565
    Abstract: The invention relates to a tungsten electrode which causes minimal cracking when sealed in a quartz glass envelope. The invention includes forming a substantially uniform oxide coating on a selected portion of the shank of a tungsten electrode followed by reducing the oxide coating to substantially elemental tungsten, wherein the electrode exhibits superior properties when sealed in a lamp having a quartz glass envelope. The invention also includes the electrode made by the process.
    Type: Grant
    Filed: June 25, 2003
    Date of Patent: August 10, 2004
    Assignee: Welch Allyn, Inc.
    Inventor: Dean A. Bell
  • Patent number: 6749776
    Abstract: A method of making an electron emissive material using combinatorial chemistry techniques is provided. The method includes providing a plurality of pixels of the electron emissive material, each pixel having at least one different characteristic from any other one of the plurality of pixels, and measuring at least one property of each pixel. The measurement may include a measurement of the electron emissive material work function using a Kelvin probe or other work function measurement systems.
    Type: Grant
    Filed: December 4, 2000
    Date of Patent: June 15, 2004
    Assignee: General Electric Company
    Inventors: Sung Su Han, Sylvain Simon Coulombe
  • Patent number: 6744204
    Abstract: A gas discharge lamp with at least one capacitive coupling structure (2, 3) is described, which lamp has the particular characteristic that the coupling structure (2, 3) comprises a ceramic material which comprises pure BaTiO3. In particular an additional doping of at least part of the BaTiO3 with barium leads to a material whose Curie temperature and saturation polarization are substantially higher and whose coercitive field strength is substantially smaller, so that a gas discharge lamp with a coupling structure manufactured from this material can be operated at substantially higher temperatures and at a lower operating voltage. Various dopings of the BaTiO3 with titanium, manganese, and lead are furthermore described.
    Type: Grant
    Filed: May 7, 2002
    Date of Patent: June 1, 2004
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Wilhelm Albert Groen, Petra Huppertz, Knuth Albertsen, Bernd Rausenberger
  • Publication number: 20040070344
    Abstract: A cold cathode lamp according to the present invention provide with: electrodes fixed on respective ends of a glass tube; filling a rare gas or a rare gas and mercury vapor in the glass tube; and at least surfaces of the electrodes are composed the nitride, said nitride is composed at least one of titanium (Ti), zirconium (Zr), hafnium (Hf), niobium (Nb) and tantalum (Ta).
    Type: Application
    Filed: July 31, 2003
    Publication date: April 15, 2004
    Applicant: NEC CORPORATION
    Inventors: Seiichiro Fujioka, Yasuki Kawashima
  • Patent number: 6686694
    Abstract: The present invention relates to a method for marking quartz glass lamps having at least one fusible metal foil 10, 12, which is surrounded by quartz glass, for supplying electric voltage to luminous means 15 arranged in the interior chamber of a lamp vessel, in which method the fusible metal foil 10, 12 is marked through the quartz glass by means of a laser. The invention also relates to a quartz glass lamp having at least one fusible metal foil 10, 12 which is surrounded by quartz glass, for supplying electric voltage to luminous means 15 arranged in the interior chamber of a lamp vessel, in which lamp the fusible metal foil 10, 12 forms a marking area 16, the marking of the marking area 16 taking place through the quartz glass by means of a laser.
    Type: Grant
    Filed: May 1, 2001
    Date of Patent: February 3, 2004
    Assignee: Patent Treuhand-Gesellschaft fuer e{overscore (l)}ektrische Gluehlampen mbH
    Inventors: Johann Rechermann, Xaver Brems, Georg Rosenbauer
  • Patent number: 6680574
    Abstract: A gas discharge lamp comprising an electrode including a carrier of an electrode metal, selected from the group formed by tungsten and tungsten-containing alloys, and a first coating of a first electron-emitting material, which material comprises an alkaline earth metal oxide, selected from the group formed by calcium oxide, strontium oxide and barium oxide, and a rare earth metal oxide, selected from the group formed by scandium oxide, yttrium oxide and europium oxide, in a quantity a that ranges from 0.1 to 10 wt. % by weight, is characterized by a longer service life, a higher resistance to poisoning and a robust manner of coping with a rapid succession of switching operations, as well as a short ignition stage.
    Type: Grant
    Filed: November 22, 2000
    Date of Patent: January 20, 2004
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Georg Gaertner, Wim Van Den Hoek
  • Publication number: 20040007979
    Abstract: A high-pressure discharge lamp comprises a lamp tube made of quartz glass and having a central portion formed in a spherical shape, and a pair of opposing tungsten electrodes inserted into the lamp tube. At least one of the tungsten electrodes is made of a tungsten material which contains more than 10 ppm of one of Co and Ni, or 10 ppm of Co and Ni in total, or a tungsten material which contains 20 ppm or more of at least two of Fe, Co and Ni in total, or a tungsten material which contains 20 ppm or more of Fe. Fe, Co and Ni belong to iron-group metals. The inter-electrode distance, i.e., distance between the leading ends of both tungsten electrodes is set to approximately 1-2 mm or less.
    Type: Application
    Filed: June 10, 2003
    Publication date: January 15, 2004
    Inventors: Yasushi Aoki, Masahiro Katoh
  • Patent number: 6674240
    Abstract: A gas discharge lamp, in particular a low-pressure gas discharge lamp, comprising an electrode including a carrier of an electrode metal and a first electrode coating of an electron-emitting material, which material comprises a metal powder preparation of a powder of a reducing metal selected from the group formed by aluminum, silicon, titanium, zirconium, hafnium, tantalum, molybdenum, tungsten and the alloys thereof, which metal powder preparation is provided with a powder coating containing a noble metal selected from the group formed by rhenium, cobalt, nickel, ruthenium, palladium, rhodium, iridium and platinum, and the alloys thereof, and said material comprising at least one alkaline earth metal oxide selected from the group formed by calcium oxide, strontium oxide and barium oxide, is characterized by a uniform emission current and a long service life.
    Type: Grant
    Filed: November 20, 2000
    Date of Patent: January 6, 2004
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Georg Gärtner, Wilem Jacobus Van Den Hoek
  • Patent number: 6657389
    Abstract: A glow discharge lamp has a discharge vessel, a pair of electrodes mounted in the discharge vessel, ionizable filling which is principally made of rare gas and filled in the discharge vessel, and emissive material containing zinc alloy and provided on at least one of the electrodes.
    Type: Grant
    Filed: May 29, 2002
    Date of Patent: December 2, 2003
    Assignee: Toshiba Lighting & Technology Corporation
    Inventors: Akiko Saitou, Shigeru Osawa, Nobuhiro Tamura, Noriyuki Hayama, Yoshiyuki Matsunaga, Takashi Yorifuji, Mitsuru Shiozaki, Masahiro Izumi
  • Patent number: 6626725
    Abstract: The invention relates to a tungsten electrode which causes minimal cracking when sealed in a quartz glass envelope. The invention includes forming a substantially uniform oxide coating on a selected portion of the shank of a tungsten electrode followed by reducing the oxide coating to substantially elemental tungsten, wherein the electrode exhibits superior properties when sealed in a lamp having a quartz glass envelope. The invention also includes the electrode made by the process.
    Type: Grant
    Filed: May 8, 2000
    Date of Patent: September 30, 2003
    Assignee: Welch Allyn, Inc
    Inventor: Dean A. Bell
  • Publication number: 20030178940
    Abstract: A metal halide lamp for an automobile headlight is provided, which includes an arc tube in which a pair of tungsten electrodes are provided at both ends and a metal halide as a main component of a luminescent material and xenon gas as a buffer gas are sealed, wherein the tungsten electrodes contain not more than 0.4 wt % of thorium oxide, the metal halide contains scandium iodide, and a pressure of the xenon sealed in the arc tube is at least 0.4 MPa. This makes it possible to provide a long-life metal halide lamp for an automobile headlight that can achieve a further improved lumen maintenance factor and other life characteristics during 2000 hours or more of lighting.
    Type: Application
    Filed: November 25, 2002
    Publication date: September 25, 2003
    Inventors: Masato Yoshida, Hideaki Kiryu
  • Patent number: 6624577
    Abstract: A tungsten-rhenium filament for an operation temperature between 2900 and 3200° K is disclosed. The filament comprises an aluminum-potassium-silicon (AKS) additive. The filament has a grain microstructure comprising substantially exclusively elongated interlocking grains with a Grain Aspect Ratio (GAR) not less than 12. The rhenium content of the filament is between 0.2-0.4% by weight. A method for manufacturing a rhenium-tungsten filament is also disclosed. The method comprises the following steps. An AKS doped tungsten-rhenium alloy powder is prepared with a rhenium content of 0.2-0.4% by weight. The alloy powder is pressed and presintered, and thereafter sintered with direct current. A rhenium-tungsten filament is formed, which has a metastable crystal structure. The filament is annealed below the recrystallisation temperature, and recrystallised above the crystallization temperature. There is also provided a halogen incandescent lamp with a glass envelope enclosing a tungsten-rhenium filament.
    Type: Grant
    Filed: March 19, 2001
    Date of Patent: September 23, 2003
    Assignee: General Electric Company
    Inventors: István Mészáros, Tamás Gál, György Nagy, Béla Szeles
  • Patent number: 6614188
    Abstract: A high-pressure discharge lamp employs an outer bulb that is provided with a lamp cap and surrounds a discharge vessel having a ceramic wall with a clearance. In the clear space, a conductor extends over a length L between the lamp cap and an electrode of the discharge vessel, which conductor is at least formed of a heat-resistant metal. A section Ld of the length L of the conductor is provided with an Ni coating.
    Type: Grant
    Filed: November 20, 2000
    Date of Patent: September 2, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Willem Johannes Lindhout, Mark Josephus Lucien Maria Van Dommelen, Guido Julianus Josephus Lenaerts
  • Patent number: 6603248
    Abstract: A discharge lamp (20), such as a neon lamp, comprising a laminated envelope having a gas-discharge channel and at least one external electrode (44) in communication with the gas-discharge channel (20), the laminated envelope having a front surface (32) and a back surface (28) integrated together to form a unitary envelope body essentially free of any sealing materials. The external electrode (44) comprises an electrode surface integral with the laminated envelope and a conductive medium disposed on the electrode surface. The conductive medium may be conductive tape, conductive ink, conductive coatings, frit with conductive filler or conductive epoxies. The discharge lamp may comprise a laminated envelope including a plurality of separate gas-discharge channels and external electrodes in communication with the gas-discharge channels, whereby the discharge is driven in parallel.
    Type: Grant
    Filed: September 22, 2000
    Date of Patent: August 5, 2003
    Assignee: Corning Incorporated
    Inventor: Jackson P. Trentelman
  • Patent number: 6600268
    Abstract: A short arc mercury lamp includes a luminous bulb enclosing at least mercury as a luminous material and a pair of electrodes opposed to each other; and a pair of sealing portions for sealing a pair of metal foils electrically connected to the pair of electrodes, respectively. The electrode central axis of one of the pair of electrodes is dislocated from the electrode central axis of the other electrode. The shortest distance d (cm) between the head of one of the electrodes and the head of the other electrode is larger than the value of (6M/13.6&pgr;)1/3 when the total mass of the enclosed mercury is M (g).
    Type: Grant
    Filed: May 25, 2001
    Date of Patent: July 29, 2003
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Makoto Horiuchi, Makoto Kai, Tsuyoshi Ichibakase, Tomoyuki Seki, Mamoru Takeda, Shinichi Yamamoto, Kenichi Sasaki
  • Patent number: 6597107
    Abstract: A tungsten-rhenium filament is disclosed. The filament has a re-crystallization temperature above 2000° C., and it comprises an aluminum-potassium-silicon (AKS) additive. The potassium content of the filament is between 80-110 ppm, and the rhenium content is between 0.05-0.19% by weight. A method for manufacturing a rhenium-tungsten filament is also disclosed. The method comprises the following steps. An AKS doped tungsten-rhenium alloy powder is prepared with a rhenium content of 0.05-0.19% by weight, and a potassium content between 80-110 ppm. The alloy powder is pressed and presintered, and thereafter sintered with direct current. A rhenium-tungsten filament is formed which has a metastable crystal structure. The filament is wound on a mandrel, and it is annealed on the mandrel below the re-crystallization temperature. The filament is finally re-crystallized above the re-crystallization temperature. A halogen incandescent lamp with an envelope enclosing a tungsten-rhenium filament is also provided.
    Type: Grant
    Filed: January 11, 2002
    Date of Patent: July 22, 2003
    Assignee: General Electric Company
    Inventors: István Mészáros, Tamás Gál, György Nagy, Zita Fábián
  • Patent number: 6590340
    Abstract: The high-pressure discharge lamp comprises a sealed lamp vessel (1) having a quartz glass wall (2) enclosing a discharge space (3). Metal foils (4) are embedded in the wall, connected to electrode rods (6a) projecting from the wall into the discharge space. The electrode rods (6a) have a first part (7a) and a second part (7b). The second part is made of tungsten with a diameter of 120 to 180 &mgr;m or molybdenum with a diameter of 120 to 350 &mgr;m, or tungsten-molybdenum mixtures with a diameter of 120 to 350 &mgr;m. The second part, which is positioned within the wall (2), prevents premature failure of the lamp caused by leakage.
    Type: Grant
    Filed: June 22, 1999
    Date of Patent: July 8, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Joseph F. R. Eijsermans, Dorothea Seebode, Angela Jörres
  • Patent number: 6590342
    Abstract: The electric lamp has a ceramic lamp vessel (1) having a filling of rare gas and metal halide. Current conductors (2, 3) which support electrodes (4, 5) inside the discharge vessel (1) enter the discharge vessel (1) in a gastight manner through a ceramic sealing compound (6). At least one of the current conductors (2, 3) has inside the lamp vessel (1) a first, halogen-resistant part (21, 31) which is selected from tungsten silicide, molybdenum aluminide, molybdenum boride, pentamolybdenum trisilicide and combinations of at least two of these intermetallic compounds. These compounds have a coefficient of thermal expansion which corresponds to that of the discharge vessel (1). It is thereby prevented that the discharge vessel starts leaking if the ceramic sealing compound (6) extends beyond the first part (21, 31).
    Type: Grant
    Filed: December 2, 1999
    Date of Patent: July 8, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Elisabeth Onnekes-Van Der Voort, Hendrik Dreuning, Franciscus H. Van Lierop, Peter A. Seinen, Martin F. C. Willemsen, Mark Bolech
  • Patent number: 6580218
    Abstract: A discharge tube in which a cathode with a cathode tip portion being fixed to a lead rod and an anode opposed to the cathode tip portion are encapsulated in a discharge gas atmosphere to effect arc discharge, wherein the cathode tip portion comprises: a metal substrate of an impregnated type in which a porous, refractory metal is impregnated with an electron-emissive material or a sintered type in which a refractory metal containing an electron-emissive material is sintered; and a coating of a refractory metal covering a predetermined portion in a surface of the metal substrate and having a thickness of not less than 0.02 &mgr;m nor more than 5 &mgr;m, wherein the metal substrate has a cusp pointed toward the anode, and wherein a tip portion of the cusp of the metal substrate is exposed without being covered by the coating.
    Type: Grant
    Filed: November 8, 2001
    Date of Patent: June 17, 2003
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Nobuharu Harada, Syoji Ishihara
  • Patent number: 6563256
    Abstract: Low work function materials are disclosed together with methods for their manufacture and integration with electrodes used in thermionic conversion applications (specifically microminiature thermionic conversion applications). The materials include a mixed oxide system and metal in a compositionally modulated structure comprised of localized discontinuous structures of material that are deposited using techniques suited to IC manufacture, such as rf sputtering or CVD. The structures, which can include layers are then heated to coalescence yielding a thin film that is both durable and capable of electron emission under thermionic conversion conditions used for microminiature thermionic converters. Using the principles of the invention, thin film electrodes (emitters and collectors) required for microconverter technology are manufactured using a single process deposition so as to allow for full fabrication integration consistent with batch processing, and tailoring of emission/collection properties.
    Type: Grant
    Filed: February 25, 1999
    Date of Patent: May 13, 2003
    Assignee: Sandia Corporation
    Inventors: Kevin R. Zavadil, Judith A. Ruffner, Donald B. King
  • Patent number: 6541899
    Abstract: In a lighting arrangement comprising a low-pressure discharge lamp and a high-frequency ballast for cold-igniting and operating the low-pressure discharge lamp, said low-pressure discharge lamp is equipped with electrodes which each comprise two or more double-spiral tungsten electrode bodies covered with an emitter. The switching performance of the low-pressure discharge lamp is very high.
    Type: Grant
    Filed: October 30, 2000
    Date of Patent: April 1, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Marco Haverlag, Jean Johan Heuvelmans, John Fitzgerald, Andreas Sebastianus Gertrudis Geven
  • Publication number: 20030052608
    Abstract: In a discharge lamp which has a silica glass discharge vessel with an arc tube portion and hermetically sealed portions in which in the hermetically sealed portions of this discharge vessel metal foils are installed and hermetically sealed areas are formed, in accordance with the invention has a high endurance of the sealing action in the hermetically sealed areas and thus a long service life is obtained by a coating layer being formed on at least one side of the respective metal foil. The coating layer is formed from at least one metal oxide which is selected from titanium oxide, lanthanum oxide, tantalum oxide, zirconium dioxide which can contain yttrium oxide, and from hafnium dioxide which can contain yttrium oxide. Furthermore, the metal oxide which forms the coating layer is advantageously crystalline, and moreover, can be formed over a base layer which is made of aluminum oxide or yttrium oxide.
    Type: Application
    Filed: September 10, 2002
    Publication date: March 20, 2003
    Applicant: Ushiodenki Kabushiki Kaisha
    Inventors: Yukihiro Morimoto, Katsumi Sugaya
  • Patent number: 6534919
    Abstract: In a capacitively coupled discharge lamp the electrode comprises a dielectric material that during operation is in contact with the discharge. The impedance of the dielectric material is small and its electron affinity is negative. In this way it is realized that the discharge lamp can be operated efficiently at low frequencies (less than 500 KHz).
    Type: Grant
    Filed: November 30, 1999
    Date of Patent: March 18, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Peter K. Bachmann, Bernd Rausenberger, Howard Wilson, Albrecht Kraus, Norbert Braun
  • Patent number: 6534918
    Abstract: The high-pressure discharge lamp comprises a sealed lamp vessel (1) having a quartz glass wall (2) enclosing a discharge space (3). Metal foils (4) are embedded in the wall, connected to electrode rods (6) projecting from the wall into the discharge space. The electrode rods (6) have a first part (7a) and a second part (7b) with a diameter of between 250 and 350 &mgr;m and at least an envelope (7c) made of rhenium. The second part, which is positioned within the wall (2), prevents premature failure of the lamp caused by leakage.
    Type: Grant
    Filed: June 22, 1999
    Date of Patent: March 18, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Manfred Peterek, Joseph F. R. Eijsermans, Dorothea Seebode, Marcus Kubon, Angela Jörres
  • Patent number: 6531832
    Abstract: In a discharge lamp, at least one of two main electrodes disposed at both ends of the discharge lamp includes one main electrode that comprises a sintered metal member having a slope with respect to another main electrode. A tip of the slope is positioned within a space covered by a trigger electrode coated on an outer surface of the discharge lamp in a limited area with respect to the entire circumference of a bulb of the lamp. This structure allows the discharge lamp to emit light at a stable level constantly. An electronic flash device using this discharge lamp can emit the light precisely.
    Type: Grant
    Filed: December 14, 2001
    Date of Patent: March 11, 2003
    Assignee: West Electric Co., Ltd.
    Inventors: Shinji Hirata, Haruhiko Yuhara
  • Publication number: 20020185977
    Abstract: A glow discharge lamp has a discharge vessel, a pair of electrodes mounted in the discharge vessel, ionizable filling which is principally made of rare gas and filled in the discharge vessel, and emissive material containing zinc alloy and provided on at least one of the electrodes.
    Type: Application
    Filed: May 29, 2002
    Publication date: December 12, 2002
    Inventors: Akiko Saitou, Shigeru Osawa, Nobuhiro Tamura, Noriyuki Hayama, Yoshiyuki Matsunaga, Takashi Yorifuji, Mitsuru Shiozaki, Masahiro Izumi
  • Patent number: 6492772
    Abstract: A high pressure discharge lamp has a pair of electrodes in a discharge tube. Each electrode includes a coil and an electrode rod with a tip, the coil being set around the electrode rod near the tip. The tip of the electrode rod and an adjacent portion of the coil are fused together during the initial discharge. To be more specific, the coil covers the electrode rod near the tip, with the tip of the electrode rod being left uncovered and a length of the tip being &Dgr;L that satisfies an inequality 1/50*R3≦&Dgr;L≦1/5*R3 where R3 is an outer diameter of the coil adjacent to the tip. Alternatively, the electrode can be first formed before being set in the discharge tube, by integrally melting the tip of the electrode rod and the adjacent portion of the coil using, for example, a plasma or laser.
    Type: Grant
    Filed: February 1, 2000
    Date of Patent: December 10, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Nobuyoshi Takeuchi
  • Patent number: 6489723
    Abstract: A direct-current-lighting, ultra-high-pressure mercury lamp that is resistant to loss of transparency even after being lit for a long period, and has little wastage of electrodes and particularly the cathode tip, and also exhibits a long service life. The direct-current ultra-high-pressure mercury lamp includes a cathode and anode of tungsten facing each other within a quartz glass tube, and a cathode coil which is wrapped around the cathode. The cathode is composed of tungsten doped with potassium, and the anode is composed of tungsten having a purity of at least 99.99%. The cathode coil can also be advantageously formed of tungsten having a purity of at least 99.99%.
    Type: Grant
    Filed: April 23, 2001
    Date of Patent: December 3, 2002
    Assignee: Ushiodenki Kabushiki Kaisha
    Inventor: Shoji Miyanaga
  • Patent number: 6486602
    Abstract: In the case of an electrode (5) for a high-pressure discharge lamp, at least a part of the surface of the electrode is covered with a dendritic layer (13) made from high-melting-point metal. A substantially longer service life is achieved thereby.
    Type: Grant
    Filed: March 8, 2000
    Date of Patent: November 26, 2002
    Assignee: Patent-Treuhand-Gesellschaft fuer elektrische Gluehlampen mbH
    Inventor: Carsten Setzer
  • Patent number: 6483240
    Abstract: A high pressure mercury lamp comprises a quartz envelope that contains an atmosphere and a pair of arc-discharge electrodes. These are coil-wound tungsten that has been doped to grain-stabilize the tungsten crystalline structure, e.g., with potassium or potassium and alumina. Preferred potassium doping levels of the tungsten material are in the range of 35-75 ppm. A suitable commercial product of alumina and potassium doped tungsten material is Type BSD-Sylvania. The atmosphere generally comprises a rare gas like xenon, to which is added no more than 0.2 mg/mm3 of mercury so as to keep operating pressure under 200 bar (197 atm). But the electrical power applied is sufficient to maintain arc power loadings of at least 150 watts/mm. The resultant wall loading is more than 0.8 watts/mm2, and lamp operating-power levels can be greater than 150 watts.
    Type: Grant
    Filed: March 6, 2001
    Date of Patent: November 19, 2002
    Assignee: PerkinElmer Optoelectronics, N.C., Inc
    Inventors: Daniel Joseph O'Hare, Richard O. Shaffner, Richard P. Gilliard
  • Publication number: 20020140352
    Abstract: A cold cathode discharge device with high efficiency of light emission and long life is prepared by a cold cathode having both high secondary electron emission and anti-spattering property.
    Type: Application
    Filed: March 18, 2002
    Publication date: October 3, 2002
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tadashi Sakai, Tomio Ono, Naoshi Sakuma, Zhang Li
  • Patent number: 6448712
    Abstract: A high-pressure discharge lamp which includes a light-transmitting air-tight discharge container, an electrode formed of tungsten as a main component and fixedly sealed in the discharge container, and a discharge medium containing a halide of a light emitting metal and sealed in the discharge container. The surface of the electrode is defined as follows. That is, the average value of center line average roughness Ra of the surface, is set to 0.3 &mgr;m or less, or the average value of the center line average roughness Rz of the surface of the electrode, is set to 1.0 &mgr;m or less, or the average value of the surface area increasing rate of the surface of the electrode is set to 1.0% or less.
    Type: Grant
    Filed: January 11, 2001
    Date of Patent: September 10, 2002
    Assignee: Toshiba Lighting and Technology Corporation
    Inventors: Hisashi Honda, Seiji Ashida, Kiyoshi Saita, Ariyoshi Ishizaki, Akira Itoh, Shigehisa Kawatsuru, Tatsuo Otabe
  • Patent number: 6437509
    Abstract: The invention relates to an electrode for discharge lamps, comprising a pin which is at least partially surrounded by a solid body. Said solid body consists of a material with a high melting point. The cooling body is therefore easy to mount on the pin and can be solidly connected to the same so that they form a robust unit.
    Type: Grant
    Filed: June 19, 2000
    Date of Patent: August 20, 2002
    Inventor: Thomas Eggers
  • Patent number: 6417621
    Abstract: A gas discharge lamp has electrodes of Ba(Ti1−xZrx)O3 with donor/acceptor dopants. Specific donor/acceptor combinations, an optimized content of zirconium and an optimized atomic ratio between the cations leads to ferroelectric ceramic exhibiting high values of the remnant polarization Pr and the dielectric constant &ggr;r, as well as rectangular hysteresis loop and low coercive field strengths Ec. When an alternating voltage is applied to the ferroelectric electrodes, the non-linear properties of the electrodes bring about the ignition of the lamp as well as the continuous operation thereof.
    Type: Grant
    Filed: April 7, 2000
    Date of Patent: July 9, 2002
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Detlev Hennings, Oliver Steigelmann
  • Patent number: 6407504
    Abstract: A vessel has a main body and a plugging members made of alumina. First composite electrode has a cylindrical current conductor having substantially same diameter as a diameter of the opening portion at one end of the vessel, and an electrode jointed by welded at a bottom of the current conductor exposed to inside of the vessel. The current conductor of the first composite electrodes has a cylindrical member made of alumina and a metallization layer made of molybdenum and alumina. A ceramic discharge tube is made in that the vessel and a first composite electrode have been subjected to a co-firing into an integrated body, with the first composite electrode inserted into the opening portion at one end of the vessel so that the electrode is exposed to the inner space with one end of the first composite electrode is exposed to outside of the vessel.
    Type: Grant
    Filed: August 26, 1998
    Date of Patent: June 18, 2002
    Assignee: NGK Insulators, Ltd.
    Inventor: Norikazu Niimi
  • Patent number: 6384534
    Abstract: There is provided an emissive mixture for cathodes of fluorescent lamps comprising a ceramic material having a formula (A1-x Cax)6 (Ta1-y Wy)2 O11+y, where A is barium or a combination of barium and strontium, 0≦x<0.5, 0≦y<1, and one of x or y is greater than zero. The ratio of lamp efficacy to number of lamp starts may be improved by optimizing the amount of Ca and W present in the ceramic material.
    Type: Grant
    Filed: December 17, 1999
    Date of Patent: May 7, 2002
    Assignee: General Electric Company
    Inventors: Alok Mani Srivastava, Holly Ann Comanzo, Laurence Bigio, William Winder Beers, Thomas Frederick Soules, Emoke Abasari
  • Patent number: 6376977
    Abstract: There is disclosed a silicon electrode plate including silicon single crystal used as an upper electrode in a plasma etching apparatus wherein concentration of interstitial oxygen contained in the silicon electrode plate is not less than 5×1017 atoms/cm3 and not more than 1.5×1018 atoms/cm3, and the silicon electrode plate wherein nitrogen concentration in the silicon electrode plate is not less than 5×1013 atoms/cm3 and not more than 5×1015 atoms/cm3. There can be provided a silicon electrode plate consisting of silicon single crystal used as an upper electrode in a plasma etching apparatus wherein problems due to adhesion of impurities such as heavy metal or the like can be prevented.
    Type: Grant
    Filed: May 30, 2000
    Date of Patent: April 23, 2002
    Assignee: Shin-Etsu Chemical Co., Ltd.
    Inventors: Makoto Kawai, Keiichi Goto, Kazuyoshi Tamura, Yoshihiro Kubota, Toshimi Kobayashi
  • Publication number: 20020027419
    Abstract: A discharge tube in which a cathode with a cathode tip portion being fixed to a lead rod and an anode opposed to the cathode tip portion are encapsulated in a discharge gas atmosphere to effect arc discharge, wherein the cathode tip portion comprises: a metal substrate of an impregnated type in which a porous, refractory metal is impregnated with an electron-emissive material or a sintered type in which a refractory metal containing an electron-emissive material is sintered; and a coating of a refractory metal covering a predetermined portion in a surface of the metal substrate and having a thickness of not less than 0.02 &mgr;m nor more than 5 &mgr;m, wherein the metal substrate has a cusp pointed toward the anode, and wherein a tip portion of the cusp of the metal substrate is exposed without being covered by the coating.
    Type: Application
    Filed: November 8, 2001
    Publication date: March 7, 2002
    Applicant: HAMAMATSU PHOTONICS K.K.
    Inventors: Nobuharu Harada, Syoji Ishihara
  • Publication number: 20010048274
    Abstract: The present invention relates to a method for marking quartz glass lamps having at least one fusible metal foil 10, 12, which is surrounded by quartz glass, for supplying electric voltage to luminous means 15 arranged in the interior chamber of a lamp vessel, in which method the fusible metal foil 10, 12 is marked through the quartz glass by means of a laser. The invention also relates to a quartz glass lamp having at least one fusible metal foil 10, 12 which is surrounded by quartz glass, for supplying electric voltage to luminous means 15 arranged in the interior chamber of a lamp vessel, in which lamp the fusible metal foil 10, 12 forms a marking area 16, the marking of the marking area 16 taking place through the quartz glass by means of a laser.
    Type: Application
    Filed: May 1, 2001
    Publication date: December 6, 2001
    Applicant: Patent-Treuhand-Gesellschaft fuer elektrische Gluehlampen mbh
    Inventors: Johann Rechermann, Xaver Brems, Georg Rosenbauer
  • Patent number: 6316875
    Abstract: An arc discharge lamp includes a light transmissive envelope (3), two electrodes (1, 2) disposed at least partially inside the light transmissive envelope, and a plasma forming fill which includes selenium when excited disposed inside the light transmissive envelope (3). The exterior surfaces of the part of the electrodes (1, 2) disposed inside the light transmissive envelope (3) comprise an electrode material selected from the group of molybdenum and molybdenum compounds.
    Type: Grant
    Filed: September 10, 1999
    Date of Patent: November 13, 2001
    Assignee: Fusion Lighting, Inc.
    Inventors: Douglas A. Kirkpatrick, Bruce Shanks, Donald A. MacLennan
  • Publication number: 20010038266
    Abstract: An electric lamp with a simple welding/brazing connection comprises an electric element (2) in a translucent lamp vessel (1) with current supply conductors (4, 5) and a lamp cap (6) connected to the vessel (1) and having a shell portion (7) and a base portion (8) carrying an electric contact (9). The current supply conductor (4, 5) passes through the surface of this contact (9) to the exterior and is welded/brazed to it by means of a solidified connection body (10) of aluminum with a dope of silicon in an amount ranging from 5 to 16 % weight.
    Type: Application
    Filed: March 26, 2001
    Publication date: November 8, 2001
    Inventors: Johannes Andreas Zaat, Jozef Johannes Cornelis Buelens
  • Patent number: 6249086
    Abstract: A high-pressure discharge lamp which includes a light-transmitting air-tight discharge container, an electrode formed of tungsten as a main component and fixedly sealed in the discharge container, and a discharge medium containing a halide of a light emitting metal and sealed in the discharge container. The surface of the electrode is defined as follows. That is, the average value of center line average roughness Ra of the surface, is set to 0.3 &mgr;m or less, or the average value of the center line average roughness Rz of the surface of the electrode, is set to 1.0 &mgr;m or less, or the average value of the surface area increasing rate of the surface of the electrode is set to 1.0% or less.
    Type: Grant
    Filed: December 10, 1999
    Date of Patent: June 19, 2001
    Assignee: Toshiba Lighting & Technology Corporation
    Inventors: Hisashi Honda, Seiji Ashida, Kiyoshi Saita, Ariyoshi Ishizaki, Akira Itoh, Shigehisa Kawatsuru, Tatsuo Otabe
  • Patent number: 6215248
    Abstract: Germanium needles as emitter electrodes for use in low particle generating gas ionizers in general and static eliminators in particular. They oxidize with minimal incorporation of nitrogen, and the negative polarity emitters oxidize at a greater rate than the positive polarity emitters. Negative polarity silicon emitters generate several orders of magnitude greater particle emissions than either positive or negative germanium electrodes. The mean particle size is about 0.015 &mgr;m. No particles were shed from these needles. Lowest particle generation is achieved when germanium electrodes are purged with dry air.
    Type: Grant
    Filed: July 15, 1997
    Date of Patent: April 10, 2001
    Assignee: Illinois Tool Works Inc.
    Inventor: Charles G. Noll