Inductive Or Capactive Excitation Patents (Class 372/82)
  • Patent number: 4618961
    Abstract: The present invention is a configuration of electrodes in a transversely excited gas laser which includes an elongated cylindrical chamber with a laser gas confined therein, a pair of reflectors which reflect light energy from a discharge of the laser gas within the chamber so that the light energy travels longitudinally the length thereof, an rf generator which applies a voltage of alternating polarity between the electrodes at a frequency ranging from 10 Mhz to about 3 GHz to establish the laser gas discharge, a coupling circuit which matches the steady state reactive impedance of the chamber to the impedance of the rf generator and couples the rf generator to the electrodes. The configuration of the electrodes, each of which is formed from an electrically conductive material and is in the shape of a continuous helix, includes a first electrode and a second electrode each of which is disposed opposite to the other on the outer surface of the chamber in a first plane.
    Type: Grant
    Filed: December 16, 1982
    Date of Patent: October 21, 1986
    Inventor: Leroy V. Sutter, Jr.
  • Patent number: 4606030
    Abstract: Transitions from the 2p.sup.4 (.sup.1 S.sub.0)3s .sup.2 S.sub.1/2 state of atomic fluorine to all allowed lower states produces laser emission at six new wavelengths: 680.7 .ANG., 682.6 .ANG., 3592.7 .ANG., 3574.1 .ANG., 6089.2 .ANG., and 6046.8 .ANG.. Coherent radiation at these new wavelengths can be generated in an atomic fluorine laser operated as an amplifier or as an oscillator.
    Type: Grant
    Filed: July 6, 1984
    Date of Patent: August 12, 1986
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Joseph Berkowitz, Branko M. Ruscic, John P. Greene
  • Patent number: 4597086
    Abstract: A coaxial type laser oscillator to carry out excitation of laser medium gas by voiceless discharge with high performance.The laser oscillator is constructed in such a manner that at least a pair of ring-shaped electrodes are disposed on and around the outer peripheral surface of the discharge tube, and alternating current voltage is applied across the electrodes so as to enable the voiceless discharge to be generated in the discharge tube and to output laser beam outside the oscillator.
    Type: Grant
    Filed: July 16, 1984
    Date of Patent: June 24, 1986
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Yoshihide Kimbara
  • Patent number: 4596018
    Abstract: A circular bore transversely excited gas discharge laser is disclosed which may be constructed and operated with no physical contact between the active discharge and the metal excitation electrode structure. The discharge is excited by RF in the frequency range 10 MHz to 1 GHz applied to a transverse metal electrode structure designed to maintain a relatively uniform electric field in the discharge bore. The disclosed laser may be configured as a waveguide laser or a large bore laser operating in a non waveguide mode.A means for inductively coupling RF energy from a suitable RF energy source to the electrode structure and a means for attaching mirrors to the discharge tube using no organic sealing material is disclosed. Without physical contact between the active discharge and the metal excitation electrode structure or organic sealants, long lifetime, superior laser performance, and capability for liquid cooling of the discharge tube is achieved.
    Type: Grant
    Filed: October 7, 1983
    Date of Patent: June 17, 1986
    Assignee: Minnesota Laser Corp.
    Inventors: Carl L. Gruber, Gerald R. Willenbring
  • Patent number: 4593397
    Abstract: A laser device with a discharge tube forming a closed envelope with cylindrical end portions connected by an elongated constricted center portion and having external electrodes at the end portions, fed from a source of short pulses with a width measured in nanoseconds, capacity coupled to the discharge plasma. The discharge plasma may include metal vapor, a metal halide, including mercury halide, and internal electrodes may be included in the closed envelope but coupled to the external electrodes by capacity coupling so as to avoid any connections from electrodes passing through the glass or fused silica envelope.
    Type: Grant
    Filed: March 15, 1979
    Date of Patent: June 3, 1986
    Assignee: GTE Laboratories Incorporated
    Inventors: Joseph M. Proud, Donald H. Baird, Jerry M. Kramer, Joseph E. Lester
  • Patent number: 4577323
    Abstract: An improved RF-waveguide laser has a waveguide with an asymmetric cross section that provides improved suppression of high order modes and increased efficiency.
    Type: Grant
    Filed: September 6, 1983
    Date of Patent: March 18, 1986
    Assignee: United Technologies Corporation
    Inventors: Leon A. Newman, John T. Kennedy
  • Patent number: 4553242
    Abstract: A gas laser of circular cross section perpendicular to the direction of beam propagation and having an optical resonator is disclosed. The laser has, for continuous or modulated continuous beam operation, a metal tube as inside conductor, which is connected to a high-frequency voltage source. An outside conductor, which is coaxial with the inside conductor consists of a tube of metal of good electrical conductivity. The inside conductor is surrounded, leaving an intervening space, by a jacket tube of dielectric or metallic material. A dielectric cooling liquid of electrical insulating quality and low loss factor for high-frequency fields flows through the space between the inside conductor and the jacket tube.
    Type: Grant
    Filed: April 19, 1984
    Date of Patent: November 12, 1985
    Assignee: W.C. Heraeus GmbH
    Inventors: Hans Opower, Volker Ernst
  • Patent number: 4547883
    Abstract: A laser having its lasing medium located within two or more portions of a single optical cavity. The lasing media within different portions of a single optical cavity are excited in sequence to obtain lasing actin over an extended temporal period.
    Type: Grant
    Filed: September 16, 1983
    Date of Patent: October 15, 1985
    Assignee: Northrop Corporation
    Inventors: David B. Cohn, Hiroshi Komine
  • Patent number: 4539685
    Abstract: A passively Q-switched RF powered laser provides a variable output pulse format by controlling the duration of applied RF power and the time interval between application of power. High repetition rates may be used for scanning and target acquisition in a laser radar system and low repetition rates may be used for ranging.
    Type: Grant
    Filed: September 2, 1982
    Date of Patent: September 3, 1985
    Assignee: United Technologies Corporation
    Inventors: Richard A. Hart, Charles Bartkowski
  • Patent number: 4534035
    Abstract: This invention relates to a method and apparatus by which two series-connected glow discharge devices may be connected to a main power supply without interposing an output switch. The two series-connected glow discharge devices may be used within a single laser or in two different lasers which are pumped simultaneously. Both glow discharges may be initiated by a balanced main power supply, a single ended main power supply or a prepulse power supply in conjunction with a main power supply.
    Type: Grant
    Filed: August 9, 1983
    Date of Patent: August 6, 1985
    Assignee: Northrop Corporation
    Inventor: William H. Long
  • Patent number: 4509176
    Abstract: A longitudinal-discharge-pulse laser has two coaxial sections in the form of glass tubes joined together by a grounded central electrode and terminated by two outer electrodes. Each glass tube carries on its outer surface a multiplicity of metal rings connected in parallel, via a step-up transformer, to the anode of a first thyratron for energization with a steep negative pulse to generate a corona effect for the preionization of a gas mixture in the tubes on command of a pulse-cadence generator. This generator also controls a second thyratron, with a predetermined delay, which applies negative trigger pulses to the two outer electrodes for initiating a pumping discharge of the laser.
    Type: Grant
    Filed: June 15, 1982
    Date of Patent: April 2, 1985
    Assignee: Selenia Industrie Elettroniche Associate S.p.A.
    Inventors: Renato Marchetti, Eugenio Penco
  • Patent number: 4509174
    Abstract: The laser comprises a gas-filled channel (51) extending between a pair of metal plates (2 and 3). The laser is excited by a spark discharge through the gas from one plate to the other. The energy for the spark comes form a pair of built-in capacitors extending between the plates on either side of the channel. The plates constitute the plates of the capacitors, and apart from a plastic retaining wall (37, 39) round each capacitor, the capacitor dielectric is water. The water is advantageously pumped (47) round a cooling circuit (48), and it is not permanently damaged if an accidental discharge takes place through the water. The invention is particularly applicable to nitrogen and to excimer lasers.
    Type: Grant
    Filed: January 12, 1983
    Date of Patent: April 2, 1985
    Assignee: Compagnie Generale d'Electricite
    Inventors: Bernard Lacour, Marc Maillet, Chantal Vannier, Olivier de Witte
  • Patent number: 4493087
    Abstract: A waveguide gas laser of improved stability and efficiency resulting from novel improvements. Such improvements, including longitudinal RF excitation, unique ballasting techniques, a novel drive circuit design that is immediately responsive to defeat unstable hot spot problems, and a controlled power excitation function, result in an RF excited waveguide gas laser that substantially overcomes disadvantages of prior art devices.In one embodiment the invention consists of a longitudinally excited RF waveguide laser in which the spacing geometry of the electrodes is variable independently of the waveguide chamber geometry resulting in increased performance efficiency. In addition, hot spot problems are eliminated or substantially reduced by capacitive ballasting achieved through novel structural configurations including electrodes that are isolated from the waveguide chamber by means of a suitable dielectric spacing medium such as ceramic or aluminum oxide.
    Type: Grant
    Filed: May 27, 1982
    Date of Patent: January 8, 1985
    Assignee: Walwel, Inc.
    Inventors: Katherine D. Laakman, Peter Laakmann
  • Patent number: 4464760
    Abstract: The present invention is an improved laser bore and electrode structure including an elongated chamber for use in combination with a gas laser within which a laser gas is disposed. The laser also includes first and second reflectors which reflect light energy from the laser gas discharge within the elongated chamber so that the light energy travels longitudinally the length of the elongated chamber and first and second electrodes which transversely excite the laser gas. Each of the electrodes is formed from an electrically conductive material and they are disposed opposing each other. An energy generator applies a voltage of alternating polarity between the first and second electrodes at a frequency ranging from 10 Mhz to about 3 GHz to establish a laser gas discharge in the laser gas.
    Type: Grant
    Filed: July 30, 1982
    Date of Patent: August 7, 1984
    Inventor: Leroy V. Sutter, Jr.
  • Patent number: 4455658
    Abstract: The present invention is an improved coupling circuit for use in combination wth a gas laser including a laser bore and electrode structure which includes an elongated chamber of cross-sectional dimensions suitable for confining a laser gas discharge with the elongated chamber being formed from a dielectric material and an opposing pair of parallel electrode plates, which are formed from an electrically conductive material, for transversely exciting a laser gas. An rf generator applies a voltage of alternating polarity between the pair of parallel electrode plates at a frequency ranging from 10 MHz to about 3 GHz to establish a laser gas discharge in the laser gas. A pair of optical reflectors for reflecting and guiding light energy from the laser gas discharge so that the light energy is optically independent of the internal walls of the elongated chamber as the light energy travels longitudinally the length thereof.
    Type: Grant
    Filed: April 20, 1982
    Date of Patent: June 19, 1984
    Inventor: Leroy V. Sutter, Jr.
  • Patent number: 4443877
    Abstract: An RF excited gas laser having an optical cavity that is also a resonant cavity in the RF region is improved by the spacing of discrete inductors at fixed points along the cavity so that the problem present in the prior art of nonuniform excitation of the discharge along the cavity is eliminated and the discharge is essentially uniform throughout the cavity volume.
    Type: Grant
    Filed: February 1, 1982
    Date of Patent: April 17, 1984
    Assignee: United Technologies Corporation
    Inventors: Peter P. Chenausky, Leon A. Newman
  • Patent number: 4429398
    Abstract: An RF-discharge waveguide laser incorporates two or more waveguides sharing a common set of discharge electrodes. The device may be used to provide two lasers operating on the same or different frequencies, or a single laser with two waveguides contributing to the power output.
    Type: Grant
    Filed: February 12, 1982
    Date of Patent: January 31, 1984
    Assignee: United Technologies Corporation
    Inventors: Peter P. Chenausky, Robert J. Mongeon, Erroll H. Drinkwater, Lanny M. Laughman
  • Patent number: 4423510
    Abstract: A multilayer high temperature, low inductance capacitor consisting of alternate layers of metal and dielectric insulator materials which are inert with respect to metal halide environments is directly affixed to a planar electrode of a high temperature metal halide laser system to improve laser performance.
    Type: Grant
    Filed: November 18, 1981
    Date of Patent: December 27, 1983
    Assignee: Westinghouse Electric Corp.
    Inventors: John L. Pack, Roy K. Williams, Chi-Sheng Liu
  • Patent number: 4388720
    Abstract: The present invention comprises an apparatus which provides a combination of excitation pulses or a signle shaped excitation pulse to a plasma-recombination laser which both creates the plasma and controls the electron-ion collisional recombination rate therein. The application of the single shaped excitation pulse or combination of excitation pulses keeps the electron temperature of the plasma at a temperature unfavorable to recombination until the electron density has fallen into the optimum range for laser action. The termination of the excitation pulse or pulses results in immediate laser action having power at least several orders of magnitude over that achieved in the prior art.
    Type: Grant
    Filed: April 6, 1981
    Date of Patent: June 14, 1983
    Assignee: Bell Telephone Laboratories, Incorporated
    Inventors: William T. Silfvast, Leo H. Szeto, Obert R. Wood, II
  • Patent number: 4381564
    Abstract: A waveguide laser having a gain medium excited by a capacitively coupled self-sustained discharge is disclosed. The gain medium is disposed within a dielectric waveguide having a capillary bore centrally located therein. A gain medium such as a rare gas halide mixture is excited by a capacitively coupled discharge between a power electrode circumferentially and axially enveloping a central portion of the waveguide and ground electrodes disposed proximate the ends of the waveguide between the mirrors defining the optical cavity of the laser. A preferred embodiment of the laser further includes means for circulating the gain medium through the waveguide. The present invention is adapted for providing pulses of radiation having a wavelength in the ultraviolet and visible spectrum and pulse widths typically less than 30 nanoseconds with peak powers in excess of one kilowatt.
    Type: Grant
    Filed: July 23, 1981
    Date of Patent: April 26, 1983
    Assignee: United Technologies Corporation
    Inventor: Leon A. Newman
  • Patent number: 4375690
    Abstract: A silent discharge gas laser apparatus has three or more electrodes arranged in axial symmetry with the laser radiation axis and supplied with voltage from a multi-phase high frequency power source to establish a continuous discharge and a higher discharge density at reduced frequencies, particularly in the central region of the discharge zone.
    Type: Grant
    Filed: November 13, 1980
    Date of Patent: March 1, 1983
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Norikazu Tabata, Shigenori Yagi, Takanori Ueno, Shuji Ogawa
  • Patent number: 4363126
    Abstract: An RF-excited gas laser is improved by the addition of an inductor in parallel with a discharge resistance Rg and capacitance C.sub.wg to form a tuned circuit having a resonance frequency such that the real part of the complex impedance of the discharge chamber is matched to the output impedance of a driving oscillator and by the use of an input circuit that compensates for the imaginary part of the discharge chamber impedance.
    Type: Grant
    Filed: December 10, 1980
    Date of Patent: December 7, 1982
    Assignee: United Technologies Corporation
    Inventors: Peter P. Chenausky, Erroll H. Drinkwater, Lanny M. Laughman
  • Patent number: 4359777
    Abstract: A high efficiency gas laser which utilizes transverse electrical excitation f a laser gas medium confined in a circular cylindrical volume. Limitation of the excitation energy to only the optical mode volume of the laser eliminates the inefficiency associated with conventional TEA laser technology in which a much larger gas volume is excited for a given optical mode volume. The present invention is comprised of a new design making possible the higher efficiencies through use of dielectric coupling between concave electrodes.
    Type: Grant
    Filed: January 22, 1981
    Date of Patent: November 16, 1982
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Clifton S. Fox, Jay A. Fox, Dallas N. Barr
  • Patent number: 4352188
    Abstract: A discharge-excited waveguide gas laser is disclosed utilizing a transverse rf excitation voltage at a frequency of at least about 30 MHz applied between elongated electrodes on opposite sides of the laser discharge chamber. A plurality of shunt inductances are coupled between the electrodes externally of the chamber at periodically spaced locations along the length of the chamber. These inductances provide a negative admittance which compensates for the variation in the phase angle of the transmission line reflection coefficient along the length of the laser discharge chamber. The variation in the magnitude of the standing wave voltage produced in the chamber by the excitation voltage is reduced accordingly, thereby improving the uniformity of the laser-exciting discharge.
    Type: Grant
    Filed: July 3, 1980
    Date of Patent: September 28, 1982
    Assignee: Hughes Aircraft Company
    Inventor: Glen A. Griffith
  • Patent number: 4328464
    Abstract: A high power metallic halide laser capable of providing 300 watts of output power. More specifically, a laser amplification system is disclosed whereby a metallic halide vapor such as copper chloride (Cu.sub.3 Cl.sub.3) is caused to flow through a laser amplifier (10) and a heat exchanger means (24) in a closed loop system whereby the flow rate is altered to control the temperature rise across the length of the laser amplifier. In the copper chloride laser described in an exemplary embodiment, the copper atoms within the laser amplifier should not exceed a temperature of 3000.degree. K. so that the number of copper atoms in the metastable state will not be high enough to prevent amplification in the amplifier. In addition, a molecular dissociation apparatus (20) is provided at the input to the laser amplifier for dissociating the copper chloride into copper atoms and ions and chlorine atoms and ions.
    Type: Grant
    Filed: February 7, 1980
    Date of Patent: May 4, 1982
    Inventors: Robert A. Administrator of the National Aeronautics and Space Administration, with respect to an invention of Frosch, Thomas J. Pivirotto