Patents Assigned to Matsushita Research and Development Laboratories Inc
  • Patent number: 6528945
    Abstract: A high pressure discharge lamp formed of a polycrystalline alumina ceramic arc tube which includes a discharge zone and end tubes on each side to seal the tube, the discharge zone containing light emitting metal halides and mercury and a starting gas of argon or xenon. The end tubes have longitudinally extending openings therein. The end tubes have proximal ends adjacent the arc tube and distal ends furthermost removed from the arc tube. An electrical feed through is disposed in each of the end tubes which includes a thin metal foil section disposed between two electrically conductive lead in wire wires. One of the lead in wire wires has an electrode disposed thereon. A sealing compound seals the electrical feed through to the alumina of the end tubes at the outer ends thereof.
    Type: Grant
    Filed: February 2, 2001
    Date of Patent: March 4, 2003
    Assignee: Matsushita Research and Development Laboratories Inc
    Inventors: Timothy Lee Kelly, Jagannathan Ravi
  • Patent number: 6522085
    Abstract: An electrodeless fluorescent lamp comprises a closed-loop (“tokamak”) envelope, two ferrite cores, and an induction coil that is disposed on the envelope walls inside the closed-loop formed by the envelope. The envelope comprises two straight tubes of the same diameter. All coils' turns have essential the same length and are parallel to each other and to the closed-loop axis. Each ferrite core encircles a segment of each the coil's turn and one connecting tube. The lamp can be operated at driving frequencies of 100-600 kHz and lamp powers of 50-250 W. The ferrite core power losses were 6-8 W when the lamp was operated at a frequency of 200-300 kHz and lamp power of 140-150 W. The lamp light output was 12,500 lumen and luminous efficacy was 87 LPW.
    Type: Grant
    Filed: July 16, 2001
    Date of Patent: February 18, 2003
    Assignee: Matsushita Research and Development Laboratories Inc
    Inventors: Oleg A. Popov, Jagannathan Ravi, Robert Chandler, Edward Shapiro
  • Patent number: 5708324
    Abstract: A flat compact fluorescent lamp is disclosed. The lamp contains a fill of mercury and inert gas. The lamp includes a glass front panel (1) having an inner surface and a glass bottom panel (2) also having an inner surface. A convoluted glass partition (3) having an eccentric spiral shape and smooth bends is disposed between the inner surfaces of the front and bottom panels and with the bottom panel (2) defines a channel (4) in the lamp. The channel (4) has a fairly uniform width. A phosphor coating (6) of a predetermined density between about 3 and 5 mg./cm.sup.2 is disposed on the inner surface of the channel (4) and a phosphor coating (8) of a predetermined density of between about 0.5 and 1.5 mg./cm.sup.2 is disposed on the inner surface of the front panel (1). Two electrodes (14a & 14b) are disposed at opposite ends of the spiral in the lamp to form an arc which emits UV light to excite the phosphor (6 & 8) to emit light.
    Type: Grant
    Filed: March 18, 1996
    Date of Patent: January 13, 1998
    Assignee: Matsushita Research and Development Laboratory Inc.
    Inventors: Munisamy Anandan, Jakob Maya