Patents Examined by Xuan Thi Vo
  • Patent number: 4907853
    Abstract: An optical connector is disclosed which comprises a polarization-maintaining optical fiber inserted into an oval hole in a ferrule and fixed in the hole by an adhesive. The major axis of the oval hole coincides with the direction in which stress is applied to the polarization-maintaining optical fiber and the minor axis of the hole is approximately equal to the diameter of the polarization-maintaining optical fiber.
    Type: Grant
    Filed: November 5, 1987
    Date of Patent: March 13, 1990
    Assignee: NEC Corporation
    Inventor: Toshio Hiratsuka
  • Patent number: 4894838
    Abstract: A high pressure self-sustained gas laser operating at a high specific energy loading and long pulselength. The laser comprises an endless duct for circulating a laser generating gaseous medium and two discharge electrodes for exciting the molecules of the gaseous medium. Behind the discharge cathode electrode is an electron-beam transmitter for transmitting a beam of preionizing electrons into the gaseous medium to preionize the region near the cathode discharge electrode. The region unpreionized by the electron beam is ionized by drifting electrons from the cathode region and avalanche ionization. The applied discharge voltage never exceeds the glow voltage allowing low discharge flush factors under repetitive operation with flowing laser gas.
    Type: Grant
    Filed: October 19, 1988
    Date of Patent: January 16, 1990
    Inventors: Robert Kraft, Victor H. Hasson
  • Patent number: 4891820
    Abstract: A fast axial flow laser includes a vessel which houses heat exchangers and a pump which imparts the pumping action throughout the laser. Only one housing is necessary and this housing can also be used as an optical bench for the resonator. In one embodiment a positive displacement rotary pump is utilized and a retoreflector included to mount three fold mirrors. In the folded configuration the retroreflector provides angular stability in any two orthogonal planes parallel to the laser beam.
    Type: Grant
    Filed: July 6, 1987
    Date of Patent: January 2, 1990
    Assignee: Rofin-Sinar, Inc.
    Inventors: Joseph F. Rando, Dale E. Koop
  • Patent number: 4890289
    Abstract: A moving solid state laser gain structure is optically pumped by optical pumping radiation derived from a remote bank of diodes, preferably laser diodes. The pumping radiation is guided and concentrated from the bank to the laser gain structure over a bundle of fiber optic waveguides. In some embodiments, the laser gain structure is a slab of Nd:Glass or Nd:YAG. In some embodiments, the lasant beam is internally reflected within the slab over a zig-zag path. In one embodiment, the lasant slab is a rotating and translating disk with the pumping radiation being applied collinearly of the beam of lasant radiation. In another embodiment, the lasant slab is made up of a bundle of fiber optic waveguides.
    Type: Grant
    Filed: December 4, 1987
    Date of Patent: December 26, 1989
    Assignee: Board of Trustees of Leland Stanford, Jr. University
    Inventors: Santanu Basu, Robert L. Byer
  • Patent number: 4881238
    Abstract: In a well-known semiconductor laser, a multiple quantum well type active layer consisting of barrier layers and active layers or well layers, each of which has a thickness less than the de Broglie wavelength of electrons, is doped with an impurity, and the impurity density is made higher in the barrier layer than in the well layer. Further, in a case where the multiple quantum well active layer is held between p-type and n-type cladding layers, the well layer is undoped, the part of the barrier layer lying in contact with the well layer is undoped, and the other part of the barrier layer close to the p-type cladding layer is put into the n-conductivity type while that of the barrier layer close to the n-type cladding layer is put into the p-conductivity type.
    Type: Grant
    Filed: July 22, 1986
    Date of Patent: November 14, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Naoki Chinone, Kazuhisa Uomi, Tadashi Fukuzawa, Hideaki Matsueda, Takashi Kajimura
  • Patent number: 4881237
    Abstract: Two-dimensional surface-emitting diode laser arrays are described that take advantage of both the advanced state of development of linear laser arrays with conventional cleaved end faces and the rapid development of Si heat sink technology. A hybrid array consists of linear arrays of edge-emitting lasers that are mounted in grooves with flat bottoms and 45.degree. sidewalls etched in the top of a Si substrate containing microchannels for fluid flow on the backside. The 45.degree. sidewalls of the top Si grooves are coated with a highly reflecting metallic layer. These 45.degree. mirrors deflect the laser emission from the cleaved end faces of the linear laser arrays by 90.degree. so the emission is normal to the array surface. Use of the integral microchannel heat sink in the bottom of the Si substrate provides excellent heat removal capabilities for high power density operation.
    Type: Grant
    Filed: August 26, 1988
    Date of Patent: November 14, 1989
    Assignee: Massachusetts Institute of Technology
    Inventor: Joseph P. Donnelly
  • Patent number: 4878731
    Abstract: In accordance with the present invention, a wavelength selective passive filter is sealed onto the end of a ferrule to form a connector which may be used to increase the wavelength sensitivity of fiber optic components. In particular, such connectors may be used to increase the wavelength isolation of WDM devices.
    Type: Grant
    Filed: February 19, 1988
    Date of Patent: November 7, 1989
    Assignee: AMP Incorporated
    Inventors: Bernard G. Caron, Pamela R. Gutterman, Dale D. Murray
  • Patent number: 4876688
    Abstract: A systematic approach to the production of frequency conversion crystals is described in which a chiral molecule has attached to it a "harmonic generating unit" which contributes to the noncentrosymmetry of the molecule. Certain preferred embodiments of such harmonic generating units include carboxylate, guanadyly and imidazolyl units. Certain preferred crystals include L-arginine fluoride, deuterated L-arginine fluoride, L-arginine chloride monohydrate, L-arginine acetate, dithallium tartrate, ammonium N-acetyl valine, N-acetyl tyrosine and N-acetyl hydroxyproline. Chemical modifications of the chiral molecule, such as deuteration, halogenation and controlled counterion substitution are available to adapt the dispersive properties of a crystal in a particular wavelength region.
    Type: Grant
    Filed: August 15, 1988
    Date of Patent: October 24, 1989
    Assignee: The United States of America as represented by the Secetary of the Department of Energy
    Inventors: Francis Wang, Stephan P. Velsko
  • Patent number: 4875756
    Abstract: Disclosed is fresnel lens apparatus for optically coupling a plurality of data channels between stationary and rotating systems. Each data channel of the apparatus includes an optical data transmitter, an optical data receiver and a fresnel lens optical element. The plurality of fresnel lens optical elements are preferably annular and arranged concentrically in a plane. Each fresnel lens optical element focuses the optical data from a transmitter to a respective receiver which is positioned off axis with respect to the central axis of the concentric optical elements.
    Type: Grant
    Filed: September 27, 1988
    Date of Patent: October 24, 1989
    Assignee: Eastman Kodak Co.
    Inventors: Marvin F. Estes, Arnold W. Lungershausen
  • Patent number: 4872175
    Abstract: In a semiconductor laser device having an active layer and clad layers, lens-like portions which magnify radiation are formed in the active layer and/or a clad layer where the radiation leaks, thereby making it possible to enlarge a stripe width and to produce a fundamental mode oscillation of high output. Futher, a lens-like portion which condenses the radiation is formed at an end face of an emission port for a laser beam, thereby making it possible to narrow a radiant angle of the laser beam.
    Type: Grant
    Filed: March 28, 1988
    Date of Patent: October 3, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Shinichi Nakatsuka, Takashi Kajimura
  • Patent number: 4870648
    Abstract: An x-ray beamsplitter which splits an x-ray beam into two coherent parts by reflecting and transmitting some fraction of an incident beam has applications for x-ray interferometry, x-ray holography, x-ray beam manipulation, and x-ray laser cavity output couplers. The beamsplitter is formed of a wavelength selective multilayer thin film supported by a very thin x-ray transparent membrane. The beamsplitter resonantly transmits and reflects x-rays through thin film interference effects. A thin film is formed of 5-50 pairs of alternate Mo/Si layers with a period of 20-250 A. The support membrane is 10-200 nm of silicon nitride or boron nitride. The multilayer/support membrane structure is formed across a window in a substrate by first forming the structure on a solid substrate and then forming a window in the substrate to leave a free-standing structure over the window.
    Type: Grant
    Filed: August 7, 1987
    Date of Patent: September 26, 1989
    Assignee: The United States Department of Energy
    Inventors: Natale M. Ceglio, Daniel S. Stearns, Andrew M. Hawryluk, Troy W. Barbee, Jr.
  • Patent number: 4870651
    Abstract: A semiconductor light-emitting apparatus comprising a semiconductor laser array device with a plurality of lasing filaments and a mode-mixing device with a striped optical waveguide that attains an optical phase-coupling with the semiconductor laser array device, whereby beams from the semiconductor laser array device are emitted from the light-emitting facet of the semiconductor light-emitting apparatus via the mode-mixing device, thereby attaining a near-field pattern with a minimized ripple rate on the optical intensity.
    Type: Grant
    Filed: December 2, 1987
    Date of Patent: September 26, 1989
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Mototaka Taneya, Mitsuhiro Matsumoto, Sadayoshi Matsui
  • Patent number: 4868833
    Abstract: A lasing medium (3) and a Raman medium (20) share a common optical cavity. The lasing medium (3) projects laser light into the Raman medium (20) and, when a threshold intensity within the Raman medium is reached, the Raman medium absorbs the laser light and re-radiates coherent light at a shifted frequency. Optical elements within the system provide an optical cavity for the lasing medium and a second cavity for the Raman medium.
    Type: Grant
    Filed: August 10, 1987
    Date of Patent: September 19, 1989
    Assignee: Hughes Aircraft Company
    Inventors: Robert D. Stultz, Donald E. Narhi
  • Patent number: 4866722
    Abstract: A metal vapor laser device which can generate laser oscillations stably even if the atmospheric temperature of a metal vapor laser tube thereof varies suddenly. The metal vapor laser device comprises a metal vapor laser tube having a metal tank in which a working metal is contained, a heater for heating the metal in the metal tank, a power source circuit for the heater, a voltage detector for detecting an inter-electrode voltage of the laser tube, and a temperature detector for detecting an atmospheric temperature of the laser tube. The power source circuit includes a controlling circuit for controlling a power supply to the heater in response to detection signals from the voltage detector and the temperature detector to maintain the pressure of the metal vapor within the laser tube constant. When the atmospheric temperature of the laser tube varies suddenly, the operation of the heater is thus feed-forward controlled in response to the detection signal from the temperature detector.
    Type: Grant
    Filed: September 29, 1988
    Date of Patent: September 12, 1989
    Assignee: Ushio Denki Kabushiki Kaisha
    Inventors: Kyoichi Deki, Shinji Sugioka, Masaki Yoshioka, Hiroshige Hata
  • Patent number: 4864586
    Abstract: The present invention provides a ring laser gyro which utilizes a gas impervious block containing at least three tunnels which meet to form a closed-loop, gas containing, cavity, and allow passage of laser beams therethrough. A pair of electrodes are positioned in alignment with one of the tunnels, and positioned relative to each other to support a current through the gas and establish a glow discharge region within a portion of one of the tunnels to induce a pair of counter-propogating laser beams to propogate through the established glow discharge region in a direction transverse to the direction of the discharge current.
    Type: Grant
    Filed: December 14, 1987
    Date of Patent: September 5, 1989
    Assignee: Honeywell Inc.
    Inventor: Bruce J. Lind
  • Patent number: 4860294
    Abstract: An integrated optical arrangement for bidirectional optical message and signal transmission characterized by a common substrate having integrated thereon, a semiconductor laser, an optical detector and a direction selective coupling arrangement which coupling arrangement has a first port coupled to the laser, a second port coupled to the detector and a third port arranged for coupling light in and out of the arrangement with a first wavelength from the laser passing from the first port to the third port and the third port passing a second wavelength to the second port for detection. The arrangement further includes a wavelength selective filter being disposed in a waveguide extending to the second port for blocking light of the first wavelength but being transmissive to light of the second wavelength. The coupling arrangement can either be an optical directional coupler or a y-shaped waveguide fork.
    Type: Grant
    Filed: March 25, 1988
    Date of Patent: August 22, 1989
    Assignee: Siemens Aktiengesellschaft
    Inventors: Gerhard Winzer, Reinhard Maerz, Lothar Stoll
  • Patent number: 4858237
    Abstract: A laser arrangement includes electron beam apparatus comprising a plurality of electrodes, each of which having an aperture therethrough. The apertures are aligned along the longitudinal axis of an envelope which surrounds them and contains gas. The electrodes are electrically connected such that, of an adjacent pair, one is at a lower potential than the other. An electron beam is produced between the first electrode and an adjacent electrode, and is accelerated along the axis through the apertures, the electron current increasing in magnitude. The electron beam produced is used to provide pumping powder to the gas contained within the envelope such that it acts as a laser amplifying medium.
    Type: Grant
    Filed: May 20, 1987
    Date of Patent: August 15, 1989
    Assignee: English Electric Valve Company Limited
    Inventors: Arthur Maitland, Clifford R. Weatherup
  • Patent number: 4858238
    Abstract: Normal stimulated Raman scattering (SRS) is done in a gas cell with pump and Stokes seed input beams. The pump photons excite gas molecules in the gas cell from their ground state and the Stokes seed photons stimulate the de-excitation of the molecules back to a lower state (emitting more Stokes photons in the process). The SRS enhancer entails inputting another beam at a frequency, different from the pump and seed, tuned between a third molecular state and the Raman virtual state created by the pump/seed off-resonant two-photon transition. The third laser enhances the Raman virtual state, thereby also enhancing the two-photon transition rate. Since the two-photon transition is the SRS process, the Stokes amplification is enhanced.
    Type: Grant
    Filed: January 14, 1988
    Date of Patent: August 15, 1989
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventor: David A. Cardimona
  • Patent number: 4858243
    Abstract: A glass ceramic reflector having a uniform material composition which has an almost 100% reflectivity that is diffusive in the reflectance range of the entire solar spectrum from 450 to 900 nm wavelength. Furthermore, the ceramic material has a high absorption of ultraviolet wave lengths and low reflectivity in the infrared region to minimize thermal loading of the laser rod of high gain laser material. In one preferred embodiment, the glass ceramic reflector is mica based and has a composition of approximately 55% crystal and 45% residual glass, thereby defining a microstructure that enables the ceramic material to be machined to form an interior surface configuration that is easily closely coupled to flashlamp and laser rod components of the laser device.
    Type: Grant
    Filed: June 12, 1987
    Date of Patent: August 15, 1989
    Assignee: Raycon Corporation
    Inventor: Dan Bar-Joseph
  • Patent number: 4856020
    Abstract: A laser has a central axis, an outer envelope, a cathode end cap attached to the cathode end of the envelope, a cathode post attached at an inner end to the cathode end cap and extending axially therefrom generally coaxially along the central axis, and a laser mirror mounted to an outer end of the cathode post. An alignment mechanism is provided at the cathode end of the laser for aligning the mirror in a desired predetermined relation to the central axis. The alignment mechanism includes a cylindrical collar mounted to the cathode end cap in surrounding and outward radially spaced relation to the mirror-supporting cathode post, and a plurality of adjustment screws mounted to the collar at circumferentially spaced locations about the cathode post.
    Type: Grant
    Filed: June 15, 1988
    Date of Patent: August 8, 1989
    Assignee: Spectra-Physics, Inc.
    Inventor: Mark V. Ortiz