Patents Examined by B. R. R. Holloway
  • 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: 4894852
    Abstract: A method of producing X-rays employs a first monocrystal having parallel lattice planes and an optically flat planar face extending at the Bragg angle .theta..sub.B or less than .theta..sub.B relative to said planes, and includes:(a) exciting the monocrystal at its face, and along a line thereon, and(b) impinging Kossel photons on that line at the slant cut crystal face, at an impingement angle of 2.theta..sub.B relative to that line,(c) whereby an intense Bragg reflected narrow width X-ray emission line occurs in a direction which is an extension of the line.
    Type: Grant
    Filed: April 30, 1987
    Date of Patent: January 16, 1990
    Inventor: Kamalaksha Das Gupta
  • Patent number: 4893313
    Abstract: In a semiconductor laser device, for emitting a laser beam having a wavelength .lambda., an n-type In.sub.0.5 (Ga.sub.1-x Al.sub.x)P first cladding layer is formed on an n-type GaAs substrate. An undoped InGaP active layer is formed on the first cladding layer and a p-type In.sub.0.5 (Ga.sub.1-x Al.sub.x).sub.0.5 P cladding layer is formed on the active layer. A p-type InGaP cap layer is formed on the second cladding layer and an n-type GaAs current restricting layer is formed on the second cladding layer. The aluminum composition ratio x of the cladding layer is 0.7. The active layer has a thickness of 0.06 .mu.m and the cladding layers have the same thickness H of 0.85 .mu.m. The active layer and the cladding layers have refractive indices n.sub.a and n.sub.c which satisfies the following inequalities:0.015.DELTA..sup.1/2 <d/.lambda.<0.028.DELTA..sup.-1/2and.DELTA.=(n.sub.a.sup.2 -n.sub.c.sup.2)/2n.sub.a.sup.
    Type: Grant
    Filed: March 14, 1989
    Date of Patent: January 9, 1990
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Genichi Hatakoshi, Kazuhiko Itaya, Shigeya Naritsuka, Masayuki Ishikawa, Hajime Okuda, Hideo Shiozawa, Yukio Watanabe, Yasuo Ohba, Yoshihiro Kokubun, Yutaka Uematsu
  • Patent number: 4890288
    Abstract: A light quantity control device suitable for use in a laser beam printer. A controller varies the quantity of light emitted by a semiconductor laser so as to maintain a constant light quantity, regulating the rate of variation of the light quantity according to the output of a monitor for detecting the quantity of light emitted from the semiconductor laser.
    Type: Grant
    Filed: August 21, 1987
    Date of Patent: December 26, 1989
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshihiko Inuyama, Junichi Kimizuka, Akihisa Kusano, Kaoru Sato, Takashi Soya
  • Patent number: 4890291
    Abstract: A laser oscillator control circuit controls a command voltage to control the output power of a laser. The laser oscillator control circuit has pulse generating means (8) that employs a timer for generating a pulse train in response to a signal from time setting means (5, 6) which sets an on-time and an off-time. The laser oscillator cotnrol circuit also has bias command voltage setting means (9) for setting data defining a bias command voltage at which an electric discharge can be started, and output voltage setting means (10) for setting data defining an output power voltage which is the sum of the output power and the bias command voltage. A selector (11) selects and outputs the output power voltage when the pulse train is on and selects and outputs the bias command voltage when the pulse train is off. The output from the selector is converted by a D/A converter (12) into an analog voltage to control a high-frequency power supply (21).
    Type: Grant
    Filed: November 3, 1988
    Date of Patent: December 26, 1989
    Assignee: Fanuc Ltd.
    Inventor: Etsuo Yamazaki
  • Patent number: 4890290
    Abstract: A laser light source with reduced sensitivity to optical feedback effects comprises an emitter device for emitting laser light. A body of electro-optic material is optically coupled to the emitter device for receiving and propagating light emitted by the emitter device. A time-varying electric field is established in the body of electro-optic material. Consequently, the frequency of the light emitted by the laser diode is shifted when it propagates through the body of electro-optic material.
    Type: Grant
    Filed: January 9, 1989
    Date of Patent: December 26, 1989
    Inventor: Ralph T. Hawkins, II
  • Patent number: 4887276
    Abstract: An improved shared aperture sampler for high power laser beams includes a buried mirror positioned behind a dichroic reflective surface that reflects the high power beam and permits the sample beam to pass through and to be focused or deflected by the buried mirror.
    Type: Grant
    Filed: April 16, 1987
    Date of Patent: December 12, 1989
    Assignee: United Technologies
    Inventor: John H. Bluege
  • Patent number: 4887274
    Abstract: A Semiconductor laser device comprising a quantum well region with a superlattice structure that functions as an active region, wherein the superlattice quantum well region is composed of alternate layers consisting of a plurality of first Al.sub.x Ga.sub.1-x As thin films and a plurality of second Al.sub.y Ga.sub.1-y As thin films (0<x<y.ltoreq.1).
    Type: Grant
    Filed: December 14, 1987
    Date of Patent: December 12, 1989
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Toshiro Hayakawa, Takahiro Suyama, Kosei Takahashi, Masafumi Kondo
  • Patent number: 4884277
    Abstract: An intracavity frequency-modified laser of improved amplitude stability is obtained through the use of a plurality of nonlinear optical crystals within the laser cavity. Extremely low noise operation of such a multiple crystal laser is achieved by measuring the noise in its output radiation as a function of the temperature of its optical cavity and maintaining the cavity temperature at a value that results in low noise production during subsequent operation.
    Type: Grant
    Filed: June 16, 1988
    Date of Patent: November 28, 1989
    Assignee: Amoco Corporation
    Inventors: Douglas A. Anthon, Donald L. Sipes, Jr.
  • Patent number: 4880996
    Abstract: An optical parametric amplifier system is used to illuminate an object of interest with a signal beam, and parametrically mix the signal beam from the object with a pump beam to produce a down converted idler beam which maintains an image of the object of interest but which has a frequency which equals the difference between the frequencies of the pump beam and the signal beam. A signal laser is used to illuminate the object of interest, while a pump laser produces the pump beam. A beam combiner mirror produces a combined output by receiving and combining the pump beam and the signal beam. Finally, a nonlinear crystal receives and down converts the combined output of the beam combiner mirror to produce the idler beam by parametrically mixing the signal beam with the pump beam. When a KDP nonlinear crystal is used, the crystal optic axis may be rotated with respect to the direction of propagation of the idler beam to spectally score and amplify the image of the object of interest.
    Type: Grant
    Filed: August 19, 1988
    Date of Patent: November 14, 1989
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Phillip R. Peterson, Athanasios Gavrielides, David A. Cardimona
  • Patent number: 4879722
    Abstract: An efficient, compact source of coherent radiation in the infrared, visible and ultraviolet portion of the spectrum which is capable of modulation rates over the range from O Hz to in excess of 1 GHz. The radiation is produced by optical mixing within an external optical cavity wherein at least one of the interacting beams of light is provided by a solid state device selected from the group consisting of laser diodes, laser diode arrays and diode-pumped solid state lasers.
    Type: Grant
    Filed: November 25, 1987
    Date of Patent: November 7, 1989
    Assignee: Amoco Corporation
    Inventors: George J. Dixon, Douglas W. Anthon, John H. Clark
  • Patent number: 4879723
    Abstract: An efficient, compact source of coherent radiation in the infrared, visible and ultraviolet portion of the spectrum which is capable of modulation rates over the range from 0 Hz to in excess of 1 GHz. The radiation is produced by optical mixing within the optical cavity of a laser by introducing input radiation into the optical cavity where: (a) the cavity is that of a diode-pumped solid state laser, and/or (b) input radiation is provided by a solid state device selected from the group consisting of laser diodes, laser diode arrays and diode-pumped solid state lasers.
    Type: Grant
    Filed: July 27, 1987
    Date of Patent: November 7, 1989
    Assignee: Amoco Corporation
    Inventors: George J. Dixon, Douglas W. Anthon, John H. Clark
  • Patent number: 4878225
    Abstract: A controlling apparatus for a laser diode which is used in a laser printer or the like to transmit laser beam light rays. According to the output characteristics of the laser diode, a bias is applied in the current region (from 0 to Ixm) of approximately 0 in radiation output. The control object period (from Ix to Ixm) is divided into many stages to perform the radiation output control so as to effect the high-precision output control without the provision of a more complicated circuit. The central processing unit outputs the control signal into the duty controlling means, so that the output of the laser diode may be automatically held constant in accordance with the predetermined process or the operation arranged in advance.
    Type: Grant
    Filed: March 20, 1989
    Date of Patent: October 31, 1989
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Masahiko Aiba, Yukio Mizuno
  • Patent number: 4876687
    Abstract: A free-electron laser has a wiggler for a linear electron beam comprising two sets of magnetic polepieces 26, 28 periodically spaced along opposite sides of the beam. The polepieces of one set 28 are displaced along the beam from the other set 26 by one-half period. A uniform longitudinal magnetomotive force generates fields between polepieces having transverse components 22 alternating between the sets 26, 28, providing a very short periodicity and hence, high frequency wave radiation.
    Type: Grant
    Filed: February 13, 1989
    Date of Patent: October 24, 1989
    Assignee: Varian Associates, Inc.
    Inventor: Joseph Feinstein
  • Patent number: 4876694
    Abstract: This invention relates to an external cavity slab laser system for pulsed or continuous wave operation consisting of an optically excited, water cooled single or multiple active mirror slab configurations with the external cavity formed by the active mirror and a passive mirror set parallel to each other and separated from each other by a distance greater than the thickness of the slab. Laser beams of both circular and elliptical cross-section can be amplified by the invention which has application in medical apparatus, industrial workstations and defense systems.
    Type: Grant
    Filed: December 23, 1988
    Date of Patent: October 24, 1989
    Assignee: Advanced Lasers Limited
    Inventor: John L. Hughes
  • Patent number: 4872173
    Abstract: In a method and apparatus for stabilizing the emission spectrum of a semiconductor laser diode, an external optical cavity is coupled to the laser diode to couple light from an active region of the laser diode to the external cavity and from the external cavity to the active region of the laser diode. The phase of light coupled from the external cavity to the active region of the laser diode is dithered about a phase operating point at a dither frequency. A component of the forward voltage across the laser at the dither frequency is sensed and a feedback signal indicative of the amplitude of said component of the forward voltage and the phase of said component of the forward voltage relative to the phase of the dither is generated. The phase operating point is changed in response to the feedback signal to minimize the amplitude of said component of the forward voltage. The method and apparatus are useful for stabilization of laser diodes used in high performance optical communications systems.
    Type: Grant
    Filed: September 2, 1988
    Date of Patent: October 3, 1989
    Assignee: Northern Telecom Limited
    Inventor: Bruce A. Richardson
  • Patent number: 4872180
    Abstract: A novel method for reducing the facet reflectivities of semiconductor light sources and amplifiers concerns the use of a bulk (non-waveguiding) index-matched regrown end cap region at both of the major facet surfaces of the amplifier. The amplifier has a tilted stripe geometry which, in combination with the end cap regions, enable the amplifier to reproducibly achieve facet reflectivities of less than 10.sup.-5 while avoiding a facet coating step. The improved optical amplifier is more amenable to mass production and less sensitive to both wavelength and polarization.
    Type: Grant
    Filed: June 16, 1989
    Date of Patent: October 3, 1989
    Assignee: GTE Laboratories Incorporated
    Inventors: William C. Rideout, Elliot Eichen
  • Patent number: 4868836
    Abstract: A control system particularly for a modulated laser diode such as for use in laser printers, laser communication systems, optical data storage and other uses employs bipolar integrated circuitry on a single chip with very few external components. The circuit is simple and of low cost and dependable construction and compensates for relatively slow changes in the output characteristics of the laser diode as caused by aging, temperature changes or other varying conditions. The drift compensation is accomplished through current differencing and combining a current difference signal with a modulation input signal to drive the laser diode.
    Type: Grant
    Filed: February 27, 1986
    Date of Patent: September 19, 1989
    Assignee: Spectra-Physics, Inc.
    Inventor: P. Guy Howard
  • Patent number: 4867708
    Abstract: An electric jack for receiving a plug to form the electric connection therebetween includes a main body made of electrically insulated resin and a plurality of movable contact strips. The main body has formed therein; a central hole through which the plug is insertable in an axial direction; a plurality of contact strip-clamping recesses extending in a direction perpendicular to the axial direction, the recesses being arranged in parallel with each other in the axial direction; a plurality of contact strip-fitting holes each being communicated with respective recesses; and a window portion through which the recesses are communicated with the central hole. The movable contact strip has a fitting portion to be inserted into the fitting hole of the main body and a contact portion to be clamped into the recess of main body. When the movable contact strip is inserted into the main body, the contact portion of movable contact strip is partially projected into the central hole through the window portion.
    Type: Grant
    Filed: December 22, 1987
    Date of Patent: September 19, 1989
    Assignee: Iizuka Electric Industry Company Limited
    Inventor: Akichika Iizuka
  • Patent number: 4868578
    Abstract: A portable reflector antenna assembly which is readily assemblable and disassemblable for use in the field has a triangular base frame employing three beam members which are joined together at their ends with hinge type knuckles which are slidably positioned on three legs. The legs have integral cup shaped pads near the bottom ends thereof and are driven into the ground until the cups abut against the ground to provide lateral and vertical support in the soil. The frame can be adjusted on the legs for both height and leveling by virtue of the slidable movement of each of the knuckles along the legs, and when in the desired position are clamped to the legs by means of lever-cam actuated draw bolts. The reflector member of the antenna is supported along its rim by means of pivotal supports and clamps, the bottom edge of the antenna being slidably adjustable in azimuth along the curved front beam member of the frame and clamped to the front beam member by means of clamping members.
    Type: Grant
    Filed: July 13, 1987
    Date of Patent: September 19, 1989
    Inventors: Robert F. Bruinsma, Delmer L. Thomas