Patents Examined by B. R. R. Holloway
  • Patent number: 4962505
    Abstract: In a solid-state laser device having a laser medium, a reflector member has first and second curved portions surrounding first and second reflector axes, respectively, and an extension portion extended from the first and the second curved portions towards a principal surface of the laser medium for defining an internal space together with the curved portions. Within the internal space, first and second lamps are disposed farther from the principal surface than the first and the second reflector axes, respectively, with first and second lamp axes of the first and the second lamps juxtaposed to the reflector axes and an optical axis of the laser medium. Each curved portion has an arcuate internal surface which forms a partially circular cylinder having a center axis as the reflector axis. Alternatively, the arcuate internal surface of each curved portion forms a partially elliptic cylinder having a symmetry axis as the reflector axis and an outside focal line with which the lamp axis substantially coincides.
    Type: Grant
    Filed: January 30, 1989
    Date of Patent: October 9, 1990
    Assignees: Hoya Corporation, Research Development Corporation
    Inventors: Takayasu Mochizuki, Josef R. Unternahrer, Mitsuhisa Moriyama
  • Patent number: 4942442
    Abstract: Radiation-induced effects discovered in layered structures of conductor and semiconductor materials are utilized in radiation-sensitive devices such as, e.g., highly linear as well as highly nonlinear position sensors. Such devices includes a structure of alternating layers of conductor and semiconductor materials, and electrical contacts are provided between which a radiation-induced voltage appears. Among suitable layer materials are silicon and titanium, and resulting devices are sensitive to electromagnetic as well as to particle radiation.
    Type: Grant
    Filed: April 27, 1989
    Date of Patent: July 17, 1990
    Assignee: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Clyde G. Bethea, Daniel Brasen, Barry F. Levine, Ronald H. Willens
  • Patent number: 4930136
    Abstract: A plurality of thin wall ceramic-metal segments are brazed together to form a gas laser tube assembly. Within each segment there is mounted a refractory metal ferrule with a central hole. The series of holes formed in the ferrules define the discharge bore. A plurality of ferrules are mounted in each segment and each ferrule is separately mounted within a heat dissipating fin structure.
    Type: Grant
    Filed: March 7, 1989
    Date of Patent: May 29, 1990
    Assignee: American Laser Corporation
    Inventor: Edwin G. Chaffee
  • Patent number: 4922501
    Abstract: There is disclosed an apparatus for translating the focal points of curved mirrors in a dye laser along a straight line comprising an experimentally selected pivot point for each mirror and a means for causing each mirror to pivot about its pivot point. Rotation of the mirror about the pivot point causes the incoming beam to strike the mirror in a different place on the curved surface such that the angle of reflection changes in such a manner as to compensate for the arcuate movement of the mirror around the pivot point. Also disclosed are hinge designs to allow a mirror to pivot about an apparent pivot point which is much farther away from the mirror than the hinge. Also disclosed are a method for attaching the mirror supports to the laser frame in dye laser construction and a method for tuning the dye laser so constructed for optimum lasing efficiency.
    Type: Grant
    Filed: September 30, 1987
    Date of Patent: May 1, 1990
    Assignee: Spectra Physics, Inc.
    Inventor: Stephen Wolgast
  • Patent number: 4922496
    Abstract: Apparatus for providing self-organized, phase-matched harmonic generated radiation which includes a single-mode fiber doped with ytterbium or ytterbium-aluminum which is placed in a laser cavity having a mode-locking and a Q-switching apparatus.
    Type: Grant
    Filed: December 17, 1987
    Date of Patent: May 1, 1990
    Assignee: Polaroid Corporation
    Inventor: Hong Po
  • Patent number: 4922497
    Abstract: An optical logic circuit which is high in operation speed, low in power dissipation, and capable of operating at room temperature, possesses a semiconductor laser biased at a constant current higher than a threshold current. A light input is injected into the laser, the light input differing in the polarization direction of its oscillation mode. The output light of the semiconductor laser has a bistability characteristic with respect to the light input.
    Type: Grant
    Filed: February 7, 1989
    Date of Patent: May 1, 1990
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yoshihiro Mori, Jun Shibata
  • Patent number: 4922502
    Abstract: In a solid-state laser device comprising a slab-shaped laser medium, first through n-th excitation units are arranged on the slab-shaped laser medium to define first through n-th partial zones and to generate first through n-th laser beams from the first through n-th partial zones along optical axes, respectively. In order to selectively energize the first through n-th excitation units, a reference light beam is previously generated by a beam generator to be delivered through a fixed mirror and a beam distributor to a selected one of the first through n-th partial zones. Thereafter, the reference light beam travels through the slected partial zone to be received by a photosensor. The photosensor detects the selected partial zone to energize a selected one of the first through n-th excitation units that is made to correspond to the selected partial zone.
    Type: Grant
    Filed: June 29, 1988
    Date of Patent: May 1, 1990
    Assignee: Hoya Corporation
    Inventors: Josef F. Unternahrer, Hiroshi Sekiguchi
  • Patent number: 4920387
    Abstract: A light emitting device includes a luminescent layer having at least two layers comprising non-single crystalline silicon containing hydrogen atoms laminated and having a homo-junction, and at least a pair of electrodes connected electrically to the luminescent layer, the non-single crystalline silicon layer having an optical band gap of 2.0 eV or higher and a localized level density at mid-gap of 10.sup.16 cm.sup.-3.eV.sup.-1 or less.
    Type: Grant
    Filed: September 13, 1989
    Date of Patent: April 24, 1990
    Assignee: Canon Kabushiki Kaisha
    Inventors: Katsuji Takasu, Masafumi Sano, Hisanori Tsuda, Yutaka Hirai
  • Patent number: 4916712
    Abstract: There is provided an optically pumped laser having highly reflective coatings on opposite sides such that multiple reflections of radiation between the reflective coatings of the opposed sides produce lasing in a transverse mode. A plurality of diode lasers mounted in a linear array along the opposed sides with reflective coatings provide pumping emission to the laser. An optical alignment means consisting of prisms receive the stimulating emission from individual diode lasers and align individual stimulating emission such that it is colinear with the reflective radiation within the laser cavity.
    Type: Grant
    Filed: July 27, 1989
    Date of Patent: April 10, 1990
    Assignee: McDonnell Douglas Corporation
    Inventor: Gerald M. Bender
  • Patent number: 4910744
    Abstract: A semiconductor laser device comprising a semiconductor substrate, an active layer having a refractive index greater than that of said substrate and having an energy gap smaller than that of said substrate, and a cladding layer having a conductivity type different from that of said substrate, in that order, resulting in a double-heterostructure, wherein two parallel grooves with a given distance therebetween are disposed in the double-heterostructure so as to reach said substrate and a first burying layer having the same conductivity type as said substrate, a second burying layer having a conductivity type different from that of said substrate and a third burying layer having the same conductivity type as said substrate are disposed outside of the two grooves in that order, and moreover a semiconductor layer with the flat surface having a conductivity type different from that of said substrate is disposed over the third burying layer and the area positioned between the two parallel grooves.
    Type: Grant
    Filed: December 8, 1987
    Date of Patent: March 20, 1990
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Toshihiko Yoshida, Haruhisa Takiguchi, Shinji Kaneiwa, Hiroaki Kudo
  • Patent number: 4908833
    Abstract: To overcome the deleterious effects of the nonuniform frequency modulation response in semiconductor lasers due to current injection in direct frequency modulation applications, it has been determined that the linewidth enhancement factor .alpha. be made as large as possible. In one embodiment, distributed feedback lasers well suited for frequency modulation lightwave communication systems are designed to have an integrated feedback element such as a corrugation grating whose effective pitch is selected to cause the Bragg wavelength and, therefore, the laser operating wavelength to be longer than the wavelength at substantially the maximum gain or gain peak in the semiconductor structure without the grating. That is, the wavelength of the grating is effectively detuned toward the longer wavelength and lower energy side of the peak of the gain profile.
    Type: Grant
    Filed: January 27, 1989
    Date of Patent: March 13, 1990
    Assignees: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Andrew R. Chraplyvy, Thomas L. Koch, Robert W. Tkach
  • Patent number: 4907235
    Abstract: Intra-cavity generation of second and higher harmonic frequency laser radiation is improved by inclusion of a lens or multiple-lens arrangement that focuses electromagnetic radiation emitted by the active laser medium on a wavelength conversion means within the cavity or on removal means to remove the second or higher harmonic radiation from the cavity.
    Type: Grant
    Filed: July 7, 1989
    Date of Patent: March 6, 1990
    Assignee: Laserscope
    Inventor: Dirk J. Kuizenga
  • Patent number: 4905253
    Abstract: To overcome the deleterious effects of the nonuniform frequency modulation response in semiconductor lasers due to current injection in direct frequency modulation applications, it has been determined that the linewidth enhancement factor .alpha. be made as large as possible. In one embodiment, distributed Bragg relector lasers well suited for frequency modulation lightwave communication systems are designed to have an integrated feedback element such as a corrugation grating whose effective pitch is selected to cause the Bragg wavelength and, therefore, the laser operating wavelength to be longer than the wavelength at substantially the maximum gain or gain peak in the semiconductor structure. That is, the wavelength of the grating is effectively detuned toward the longer wavelength and lower energy side of the peak of the gain profile.
    Type: Grant
    Filed: January 27, 1989
    Date of Patent: February 27, 1990
    Assignees: American Telephone and Telegraph Company, AT&T Bell Laboratories
    Inventors: Andrew R. Chraplyvy, Thomas L. Koch, Robert W. Tkach
  • Patent number: 4903276
    Abstract: The power supply includes an oscillator (20) which generates a radio-frequency signal amplified by an amplifier (21). The amplified signal is applied to a laser (22) to initiate and maintain a discharge in the laser gaseous active medium. Power control means (24) are provided operable after initiation of the discharge to adjust the power applied to the laser to the value required to operate the laser at maximum efficiency. Automatic gain control means (25) may be provided, responding to the output from a power meter (23).
    Type: Grant
    Filed: April 29, 1988
    Date of Patent: February 20, 1990
    Assignee: Ferranti, plc
    Inventor: Iain E. Ross
  • Patent number: 4901330
    Abstract: An optically pumped laser which includes a laser diode array for generating optically pumped radiation having a uniform intensity distributed over a broad band-width, and a lasant material with an absorption band for receiving radiation within such bandwidth.
    Type: Grant
    Filed: July 20, 1988
    Date of Patent: February 13, 1990
    Assignee: Amoco Corporation
    Inventors: Thomas Wolfram, Bruce A. Vojak, Edward T. Maas, Jr., Robert D. Burnham
  • Patent number: 4901323
    Abstract: The output of an oscillator stage of a laser system is monitored by a photocell which is coupled to a feedback section to control a Pockels Cell and change the light output of the oscillator stage. A synchronizing pulse is generated in timed relation to the initiation of operation of the oscillator stage and is applied to a forward feed section which cooperates with the feedback section to maintain the light output constant for an extended time interval.
    Type: Grant
    Filed: May 1, 1987
    Date of Patent: February 13, 1990
    Assignee: Universities Research Association, Inc.
    Inventors: Jon K. Hawkins, William A. Williams
  • Patent number: 4899347
    Abstract: A laser gain medium has a diamond coating in order to strengthen it and reduce parasitic oscillations. The medium can be a slab with chamfered corners with the coating on the edge faces and the corners, or a rod with the coating going all the way around it to eliminate stress corrosion and provide a compressive stress. The medium can be Nd:YAG and the coating can have a parasitic absorbing dopant. In a laser, the length of the coating preferably is the same as the length of the medium. For the slab, siderails can be used with a length slightly shorter than that of the coating.
    Type: Grant
    Filed: May 11, 1989
    Date of Patent: February 6, 1990
    Assignee: General Electric Company
    Inventors: Norman R. Kuchar, Farzin H. Azad
  • Patent number: 4897562
    Abstract: Output efficiency in optical parametric mixing of at least two source laser beams to produce new frequencies representing the sum or difference of the source beams--where at least one source beam has two or more longitudinal modes--is improved by employing two non-linear mixing media (preferably mixing crystals), recovering the unconverted light of the original frequencies from the first mixing medium, separating it into its spectral components, delaying one of the separated components with respect to the other, and combining the separated components in the second mixing medium for conversion into a further frequency-shifted product beam.
    Type: Grant
    Filed: May 1, 1989
    Date of Patent: January 30, 1990
    Assignee: Allied-Signal Inc.
    Inventors: J. S. Krasinski, Band, Y. B., D. F. Heller
  • Patent number: 4897851
    Abstract: An optimized design for a resonator for a laser housing and assembly is disclosed, comprising a concentrically arranged plasma tube, magnet and resonator tube with the mirrors and associated optics housed at opposing ends of the resonator tube, mounted on rods extending from respective ends of the resonator tube.
    Type: Grant
    Filed: October 28, 1988
    Date of Patent: January 30, 1990
    Assignee: Spectra-Physics
    Inventors: David L. Vecht, Shinan-Chur S. Sheng
  • Patent number: 4897847
    Abstract: There is disclosed an apparatus for translating the focal points of curved mirrors in a dye laser along a straight line comprising an experimentally selected pivot point for each mirror and a means for causing each mirror to pivot about its pivot point. Rotation of the mirror about the pivot point causes the incoming beam to strike the mirror in a different place on the curved surface such that the angle of reflection changes in such a manner as to compensate for the arcuate movement of the mirror around the pivot point. Also disclosed are hinge designs to allow a mirror to pivot about an apparent pivot point which is much farther away from the mirror than the hinge. Also disclosed are methods for attaching the mirror supports to the laser frame in dye laser construction and for tuning the dye laser so constructed for optimum lasing efficiency.
    Type: Grant
    Filed: September 30, 1987
    Date of Patent: January 30, 1990
    Assignee: Spectra Physics, Inc.
    Inventor: Stephen Wolgast