Patents Examined by Rodney B. Bovernick
  • Patent number: 5835515
    Abstract: A two dimensional semiconductor laser array comprises a heat conducting base plate. A plurality of laser bars, having laser diodes stacked adjacent each other, are disposed in between a plurality of heat spreader plates and over the heat conducting base plate. Two spaced apart sidewalls are disposed on the heat conducting base plate, such that the heat spreader plate is thermally connected to said two sidewalls. The laser bars and the heat spreader plates are stacked upon each other, such that each heat spreader plate is disposed in between two of the laser bars.
    Type: Grant
    Filed: October 25, 1996
    Date of Patent: November 10, 1998
    Assignee: Lucent Technologies Inc.
    Inventor: Sun-Yuan Huang
  • Patent number: 5835655
    Abstract: A single mode optical waveguide fiber having a segmented core designed to provide a large effective area for light transmission. The large effective area reduces waveguide fiber non-linearities. The inventive waveguide is thus suited for transmission of high power signals over long distances. Embodiments of the inventive single mode waveguide including five core segments are given. The large effective area is achieved with essentially no degradation in optical or mechanical performance of the waveguide.
    Type: Grant
    Filed: January 26, 1995
    Date of Patent: November 10, 1998
    Assignee: Corning Incorporated
    Inventors: Yanming Liu, Mark A. Newhouse
  • Patent number: 5835517
    Abstract: A compact WDM optical device can demultiplex an optical laser signal containing several different wavelengths corresponding to particular channels, and, in reverse operation operate as a multiplexer to interleave several different wavelengths into a multiplexed multi-channel optical laser signal with improved insertion loss characteristics. The optical device includes a linear array of passive resonant optical cavities, in the form of Fabry-Perot filters, extending in a lateral direction and an integral array of associated microlenses extending in the lateral direction. Each microlens has a center which is offset from the central longitudinal axis of an associated Fabry-Perot filter to reflect laser radiation through the device. Each optical cavity is tuned by adjusting the longitudinal dimension thereof to a particular wavelength contained in the multi-channel optical signal. A stepped-wavelength steered laser radiation source for the optical device uses a VCSEL array with offset microlenses.
    Type: Grant
    Filed: October 4, 1996
    Date of Patent: November 10, 1998
    Assignee: W. L. Gore & Associates, Inc.
    Inventors: Vijaysekhar Jayaraman, Frank H. Peters
  • Patent number: 5832011
    Abstract: A laser having two feedback elements at least one which is wavelength selective, is provided with a demountable optical connector located between the gain medium of the laser and the wavelength selective feedback element. An optical waveguide is utilized to direct optical radiation between the demountable optical connector and the wavelength selective feedback element. The demountable optical connector, for example, a mechanical fibre connector allows the wavelength selective feedback element, for example, a fibre grating, to be exchanged cheaply, simply and quickly, and thus allows the wavelength of operation of the laser to be altered.
    Type: Grant
    Filed: October 10, 1995
    Date of Patent: November 3, 1998
    Assignee: British Telecommunications public limited company
    Inventor: Raman Kashyap
  • Patent number: 5832008
    Abstract: An eyesafe laser system includes a Q-switch crystal formed of a semiconductor host material having noncentrosymmetric tetrahedral substitutional sites doped with transition metal ions in concentrations from about 0.001 to about 0.10 atomic percent, which functions as to be a saturable absorber of light at eyesafe wavelengths with a relatively long relaxation lifetime. Co.sup.2+ :ZnSe has been demonstrated to have advantageously high absorption cross section and advantageously high relaxation lifetime at both 1.54 .mu.m (Er:glass laser) and 1.6 .mu.m (Er:YAG laser). Other candidate host materials include other zinc chalcogenides, cadmium chalcogenides and zinc oxide.
    Type: Grant
    Filed: January 24, 1997
    Date of Patent: November 3, 1998
    Assignee: Hughes Electronics
    Inventors: Milton Birnbaum, Robert D. Stultz, Marly B. Camargo
  • Patent number: 5832166
    Abstract: A terminating element (1) for a central element (9) of an optical cable (13) comprises a sleeve (3) closed at one end for receiving the end of the central element (9) or core of the optical cable (13). An open end of the sleeve (3) is provided with a pair of flexible vanes (2) or legs having seating regions (5,6) which can be clamped onto the exterior of the cable (13) and each of the legs has free ends to help center the end of the cable and the terminating element (1) into a cable introduction (15), whose junction can be sealed by a section of a shrink hose (16) or sleeve (3).
    Type: Grant
    Filed: August 28, 1997
    Date of Patent: November 3, 1998
    Assignee: RXS Kabelg arnituren GmbH
    Inventors: Rainer Zimmer, Thorsten Mueller
  • Patent number: 5832018
    Abstract: A semiconductor laser device has a GaAs substrate (11), a single- or multiple-quantum well (QW) structure including at least one InGaAs strained QW active layer (16), a pair of GaAsP or In.sub.z Ga.sub.1-z AsP barrier layers (15,17) (z.ltoreq.0.3) interposing therebetween the QW structure, and a pair of AlGaAs cladding layers (13, 19) sandwiching the pair of barrier layers (15,17) and the QW structure as a whole. The semiconductor laser prevents a catastrophic optical damage (COD) caused by recombination current due to the presence of aluminum and exhibits a high optical output power.
    Type: Grant
    Filed: February 6, 1997
    Date of Patent: November 3, 1998
    Assignee: The Furukawa Electric Co., Ltd.
    Inventor: Michio Ohkubo
  • Patent number: 5832016
    Abstract: A heat sink for slab lasers has two heat conductive members. Each heat conductive member has a generally planar surface and is configured such that a solid state laser medium is disposable therebetween while contacting the planar surfaces thereof. There is at least one window formed in at least one of the heat conductive members for facilitating pumping of the solid state laser medium. The two heat conductive members cause heat to be removed from the solid state laser medium in a manner which mitigates thermal focusing and depolarization of laser radiation stimulated within the solid state laser medium.
    Type: Grant
    Filed: January 29, 1997
    Date of Patent: November 3, 1998
    Assignee: Northrop Grumman Corporation
    Inventor: Santanu Basu
  • Patent number: 5832013
    Abstract: An intracavity modulated pulsed laser and methods of using the same. In one preferred form, an intracavity modulated pulsed laser comprises an amplification medium, a pulsed pumping source, a beam modulator, and two mirrors, one totally reflective and one partially reflective for generating at least one laser output burst comprising a plurality of sub-pulses having variably controllable peak powers. In another preferred form, a non-linear crystal is utilized to double the frequency of each laser output burst. In still another preferred form, a fluorescence feedback control circuit is utilized to control the beam modulator.
    Type: Grant
    Filed: December 17, 1996
    Date of Patent: November 3, 1998
    Assignee: American Dental Technologies, Inc.
    Inventors: Michael J. Yessik, Richard G. Thompson
  • Patent number: 5832019
    Abstract: An index-guided semiconductor laser diode made by impurity-induced layer disordering (IILD) of GaInP and AlGaInP heterostructures. In some embodiments, prior to the IILD, wing regions flanking an active mesa region are etched down close to the active layer so that the selective IILD involves a shallow diffusion only. High-performance, index-guided (AlGa).sub.0.5 In.sub.0.5 P lasers may be fabricated with this technique, analogous to those made in the AlGaAs material system. Also described are several techniques for reducing parasitic leakage current via the IILD regions, which include methods for providing p-n junctions or high band gap materials to reduce the parasitic leakage. In other embodiments, a planar structure is produced but with an ultra-thin upper cladding layer. Only a shallow IILD step is necessary to penetrate below the active region.
    Type: Grant
    Filed: November 28, 1994
    Date of Patent: November 3, 1998
    Assignee: Xerox Corporation
    Inventors: Thomas L. Paoli, Robert L. Thornton, David P. Bour, David W. Treat
  • Patent number: 5828685
    Abstract: A semiconductor laser device includes an active region, a cladding region, and a carrier blocking layer of the same conductivity type as the cladding region disposed on tho same side of the active region as the cladding region. The carrier, blocking layer has a greater impurity concentration than the cladding region.
    Type: Grant
    Filed: December 26, 1996
    Date of Patent: October 27, 1998
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Geoffrey Duggan
  • Patent number: 5828688
    Abstract: The linewidth of a distributed feedback semiconductor laser or a distributed Bragg reflector laser having one or more second order gratings is reduced by using an external cavity to couple the vertical emission back into the laser. This method and device prevent disturbance of the main laser beam, provide unobstructed access to laser emission for the formation of the external cavity, and do not require a very narrow heat sink. Any distributed Bragg reflector semiconductor laser or distributed feedback semiconductor laser that can produce a vertical emission through the epitaxial material and through a window in the top metallization can be used. The external cavity can be formed with an optical fiber or with a lens and a mirror or grating.
    Type: Grant
    Filed: October 26, 1995
    Date of Patent: October 27, 1998
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Anthony L. Cook, Herbert D. Hendricks
  • Patent number: 5828686
    Abstract: A new cartridge excimer laser system and method for generating an excimer laser beam using the system are provided. The system utilizes a cartridge (10) which contains a halogen-noble gas mixture (19), electrodes (50, 60) having external electrical connections (30, 40), and assembly (20) for transmitting a laser beam output (400), and an external gas port (90). The cartridge (10) fits onto a receptacle (100) located within a receiving compartment (200) of the laser base (300) of the new system. The cartridge (10) is easily replaced by the system operator and is refurbished by the manufacturer when the gas mixture (19) therein is exhausted.
    Type: Grant
    Filed: January 14, 1997
    Date of Patent: October 27, 1998
    Assignee: Autonomous Technologies Inc.
    Inventors: Rudolph W. Frey, Philip D. Bolen
  • Patent number: 5828680
    Abstract: A hybrid type passively and actively mode-locked laser scheme is disclosed, in which not only the capability of producing ultra-short optical pulses by the conventional passively mode-locked optical fiber laser scheme is utilized, but also the repetition rate variation capability and the optical pulse synchronization capability of the conventional actively mode-locked laser scheme are utilized. Consequently, all the advantages of the two conventional laser schemes are obtained in the present invention. Specifically, two loops are coupled together, and one of the two loops consists of a non-linear amplifying loop of the existing passively mode-locked scheme, while the other loop includes an optical modulator and an optical gain medium for the loop to perform the function of an actively mode-locked scheme. Further the other loop includes a time delay line so as to adjust the laser oscillation repetition rate.
    Type: Grant
    Filed: September 13, 1996
    Date of Patent: October 27, 1998
    Assignee: Electronics and Telecommuications Research Institute
    Inventors: Kyong-Hon Kim, Seo-Yeon Park, Hak-Kyu Lee, Min-Yong Jeon
  • Patent number: 5828684
    Abstract: A semiconductor laser source using a strained active layer of an indium gallium aluminum nitride (In.sub.x Ga.sub.1-x-y Al.sub.y N) quaternary alloy to obtain semiconductor laser sources that emit TE or TM polarized light in the wavelength range of 200 to 600 nm.
    Type: Grant
    Filed: December 29, 1995
    Date of Patent: October 27, 1998
    Assignee: Xerox Corporation
    Inventor: Christian Gilbert Van de Walle
  • Patent number: 5825798
    Abstract: The present invention relates to a laser oscillating apparatus using a semiconductor laser or the like and a method of driving a laser beam source. The present invention relates particularly to a laser oscillating apparatus or the like having a nonlinear optical medium for generating a second harmonic and capable of by-pulse driving a laser beam source with high efficiency. In the laser oscillating apparatus, a optical resonator is composed of at least a laser crystal and an output mirror. The nonlinear optical medium for generating the second harmonic is inserted into the optical resonator. The laser beam source can effect pumping on the optical resonator so that the period T of a drive pulse produced from a pulse driving means satisfies a relation in .tau..sub.FL >T-.tau. with respect to .tau..sub.FL (fluorescence lifetime).
    Type: Grant
    Filed: May 20, 1996
    Date of Patent: October 20, 1998
    Assignee: Kabushiki Kaisha Topcon
    Inventors: Masayuki Momiuchi, Hiroshi Koizumi, Masahiro Ohishi, Yoshiaki Goto, Fumio Ohtomo
  • Patent number: 5825797
    Abstract: A semiconductor laser device includes a semiconductor substrate of a first conductivity type; a lower cladding layer of the first conductivity type, an active layer, and a first upper cladding layer of a second conductivity type successively disposed on the semiconductor substrate; a first insulating film disposed on the first upper cladding layer and having a stripe-shaped opening; a ridge-striped second upper cladding layer of the second conductivity type grown in the stripe-shaped opening of the first insulating film; a second insulating film disposed on side surfaces of the stripe-shaped ridge and on the first insulating film, a region of the active layer opposite the ridge-striped second upper cladding layer serving as a laser resonator having opposed laser resonator facets. The portions of the active layer adjacent the opposed facets include window regions, each window region having a higher band gap energy than the active region generating the laser beam.
    Type: Grant
    Filed: December 20, 1996
    Date of Patent: October 20, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Yutaka Nagai
  • Patent number: 5825799
    Abstract: Laser comprising a first lasing microdisk, microcylinder or microannulus defining a microcavity having a circular cross-sectional periphery and a second waveguiding micromember spaced from the first lasing micromember in a different plane and optically coupled by resonant photon tunneling. The second waveguiding micromember includes a light output coupling for providing light output from the laser without adversely affecting the Q value and low lasing threshold of the microcavity.
    Type: Grant
    Filed: May 25, 1995
    Date of Patent: October 20, 1998
    Assignee: Northwestern University
    Inventors: Seng-Tiong Ho, Daniel Yen Chu, Jian-Ping Zhang, Shengli Wu
  • Patent number: 5825793
    Abstract: A laser having, a resonator structure including a wavelength variable laser crystal containing a fluoride and an optical part for controlling the wavelength of radiation from the laser crystal, a device to excite the laser crystal, a device for detect reflected light from the optical part as a sample beam, and a device to stabilize the output of a laser beam from the resonator structure based on the sample beam.
    Type: Grant
    Filed: May 30, 1996
    Date of Patent: October 20, 1998
    Assignee: Hitachi Metals, Ltd.
    Inventors: Tsuyoshi Miyai, Satoshi Makio, Yasunori Furukawa, Masayoshi Sato
  • Patent number: 5825802
    Abstract: An optical element providing greater conversion efficiency and comprising a pyramid having a square base and four triangular faces of equal size and shape meeting at the apex. The optical element can also comprise an octahedron or double pyramid of similar configuration.
    Type: Grant
    Filed: August 23, 1993
    Date of Patent: October 20, 1998
    Inventors: Robin K. Elkins, Martin Bottomley Grier