Patents Examined by James Menefee
  • Patent number: 7126977
    Abstract: The invention provides surface emitting semiconductor laser where a transverse mode is controllable stably, a method of manufacturing it and a light module and a light transmission device including the surface emitting semiconductor laser are provided. A surface-emitting laser of the present invention can include a resonator formed on a substrate and can emit a laser from a emitting surface installed on the upper surface of a resonator toward the direction vertical to the substrate. This surface emitting semiconductor laser further includes first and second electrodes for injecting an electric current into the resonator. At least a part of the first electrode is formed on the upper surface of the resonator and includes an aperture in the resonator. The emitting surface is installed within the aperture. The reflectivity adjustment layer is formed on the emitting surface.
    Type: Grant
    Filed: September 22, 2003
    Date of Patent: October 24, 2006
    Assignee: Seiko Epson Corporation
    Inventor: Tsuyoshi Kaneko
  • Patent number: 7126971
    Abstract: An open-path optical communication system has either optical or laser sources and communicates between the source and a detector. In a first embodiment, the laser source includes a gas cell in the laser cavity to regulate laser wavelengths based on the minimum absorption between spectral lines of the gas in the cell. The laser is tuned close to a minimum absorption wavelength and the minimum absorption line locks the laser wavelength to the minimum position. In a second embodiment, the strong absorption lines of a gas in a gas cell positioned at a receiver site are used to provide channel isolation of the receiver. In a third embodiment, an atmospheric gas provides the channel isolation. In the fourth embodiment, individual wavelength channels are positioned between the absorption lines of atmospheric or non-atmospheric gases to prevent cross-talk between adjacent channels.
    Type: Grant
    Filed: June 30, 2003
    Date of Patent: October 24, 2006
    Assignee: University of South Florida
    Inventor: Dennis K. Killinger
  • Patent number: 7126975
    Abstract: An electron-beam excitation laser has a laser structure with a light emitter and reflectors on one hand and an electron source on the other hand, wherein at least part of the light emitter or reflectors has a multidimensional photonic crystal structure. An electron-beam excitation laser includes an electron source emitting electrons and a laser structure consisting of a light emitter and reflectors, accelerates electrons from the electron source, and irradiates the electrons to the laser structure to emit a laser beam from the laser structure, wherein the reflectors and/or the light emitter in the laser structure are formed with multidimensional photonic crystals in which dielectrics with different dielectric constants are arrayed in a plurality of directions at periodic intervals, and one of the dielectrics with different dielectric constants may be formed with a light-emitting material.
    Type: Grant
    Filed: June 3, 2004
    Date of Patent: October 24, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tatsuya Iwasaki, Tohru Den
  • Patent number: 7123635
    Abstract: The present invention offers a laser oscillator device having sufficient cooling ability to maintain a lasing medium which generates high-density thermal energy at a temperature appropriate for use, while being capable of being made compact. The laser oscillator device comprises an excitation beam source for generating an excitation beam, a laser medium for receiving the excitation beam and performing optical amplification, a laser oscillator device for causing resonance of light emitted by the laser medium for laser oscillation, and a cooling system for cooling said laser medium, wherein the cooling system uses a gas as the heat-carrying medium.
    Type: Grant
    Filed: July 14, 2003
    Date of Patent: October 17, 2006
    Assignee: Cyber Laser Inc.
    Inventors: Yusuke Tamaki, Kazuya Takasago, Taisuke Miura, Hitoshi Sekita
  • Patent number: 7123641
    Abstract: In a semiconductor laser device having an oscillation wavelength of larger than 760 nm and smaller than 800 nm, on an n-type GaAs substrate (101), there are stacked in sequence an n-type first and second lower cladding layers (103, 104), a lower guide layer (106), a strained InGaAsP multiquantum well active layer (107), an upper guide layer (109), and a p-type upper cladding layer (110). Since the lower guide layer (106) is formed of InGaP, leakage of carriers from an active region is reduced. Also, since the upper guide layer (109) is formed of AlGaAs, an overflow of carriers (electrons in particular) is suppressed.
    Type: Grant
    Filed: March 1, 2004
    Date of Patent: October 17, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Shuichi Hirukawa, Hidenori Kawanishi, Katsuhiko Kishimoto
  • Patent number: 7123638
    Abstract: A tunnel junction structure comprises an n-type tunnel junction layer of a first semiconductor material, a p-type tunnel junction layer of a second semiconductor material and a tunnel junction between the tunnel junction layers. The first semiconductor material includes gallium (Ga), nitrogen (N), arsenic (As) and is doped with a Group VI dopant. The probability of tunneling is significantly increased, and the voltage drop across the tunnel junction is consequently decreased, by forming the tunnel junction structure of materials having a reduced difference between the valence band energy of the material of the p-type tunnel junction layer and the conduction band energy of the n-type tunnel junction layer. Doping the first semiconductor material n-type with a Group VI dopant maximizes the doping concentration in the first semiconductor material, thus further improving the probability of tunneling.
    Type: Grant
    Filed: October 17, 2003
    Date of Patent: October 17, 2006
    Assignee: Avago Technologies General IP (Singapore) Pte. Ltd.
    Inventors: Michael Howard Leary, Danny E. Mars, Sungwon David Roh, Danielle R. Chamberlin, Ying-Lan Chang
  • Patent number: 7123633
    Abstract: A method for maintaining the mode-locked state of a Fabry-Perot (FP) laser and a WDM light source using the same method for use in WDM optical communication are disclosed. The mode-locked state can be maintained irrespective of temperature change, without use of a temperature controller, by spectrum-slicing the incoherent light generated by a light source element and injecting the spectrum-sliced light to the FP laser, then the FP laser amplifies and outputs only a lasing mode coinciding with the wavelength of the injected light, wherein a lasing-mode interval of the FP laser is set to be less than a 3 dB linewidth of the injected light, so that at least one lasing mode exists inside the 3 dB linewidth of the injected light irrespective of changes in external temperature.
    Type: Grant
    Filed: October 22, 2003
    Date of Patent: October 17, 2006
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Dong-Jae Shin, Dae-Kwang Jung, Jea-Hyuck Lee, Seong-Taek Hwang, Yun-Je Oh
  • Patent number: 7120183
    Abstract: An electra-absorption modulator and electra-absorption modulated laser are described that include a semiconductor layer having an electrically controllable absorption. The material composition of the semiconductor layer is chosen so that the semiconductor layer is substantially transparent to light propagating through the semiconductor layer when a substantially zero or a reverse bias voltage is applied across the semiconductor layer at operating temperatures of the electro-absorption modulator that are substantially greater than 25 degrees Celsius.
    Type: Grant
    Filed: December 4, 2001
    Date of Patent: October 10, 2006
    Assignee: Optium Corporation
    Inventors: Stephen B. Krasulick, Terence D. Grenda, Paul Kit Lai Yu
  • Patent number: 7116696
    Abstract: An improved singlet delta oxygen generator (SOG) and method of its use are disclosed. The improved SOG is compact and scalable, capable of operating in a zero-gravity or low gravity environment, requires no gaseous diluent or buffer gas, and is capable of operating at pressures as high as one atmosphere. The improved SOG also efficiently utilizes the reactants and produces a O2(1?) stream that is largely free of chlorine and water vapor contamination and therefore does not require a BHP regeneration system or a water vapor trap. When used as part of a COIL system, the SOG may be part of a plenum that directly feeds the laser's nozzle. The close proximity of the SOG to the laser cavity allows operation of the SOG at higher pressures without significant depletion of available O2(1?) through collisional deactivation.
    Type: Grant
    Filed: June 3, 2003
    Date of Patent: October 3, 2006
    Assignee: KSY Corporation
    Inventor: George Emanuel
  • Patent number: 7116690
    Abstract: Embodiments of the present invention are directed to staggered arrays of laser diode bars positioned on stepped support structures. Optical waveguides may direct the outputs of the individual diode bars to a desired location, for example, a common output plane. The optical waveguides may be glass plates in certain embodiments. Waste heat generated by the diode bars may be removed from the support structures at certain locations and as a result, the diode bars may be closely positioned with respect to each other. By closely positioning the laser diode bars and directing the diode bar outputs to a desired orientation, the effective brightness and fluence may be increased for a given output area and operational power compared to the prior art. Associated methods of manufacturing staggered array couplers and producing high-power pump energy are also described.
    Type: Grant
    Filed: May 17, 2004
    Date of Patent: October 3, 2006
    Assignee: Textron Systems Corporation
    Inventor: Daniel E. Klimek
  • Patent number: 7116694
    Abstract: A transmitter array that has at least one pixel element. Each pixel element includes at least a primary semiconductor laser and a secondary semiconductor laser. In this manner, when the primary semiconductor laser is inoperative, the secondary semiconductor laser is utilized for transmission.
    Type: Grant
    Filed: December 11, 2002
    Date of Patent: October 3, 2006
    Assignee: Avago Technologies Fiber IP (Singapore) Pte. Ltd.
    Inventors: Frank H. Peters, Jonathan Simon
  • Patent number: 7116693
    Abstract: A nitride-based semiconductor light-emitting device capable of stabilizing transverse light confinement is obtained. This nitride-based semiconductor light-emitting device comprises an emission layer, a cladding layer, formed on the emission layer, including a first nitride-based semiconductor layer and having a current path portion and a current blocking layer, formed to cover the side surfaces of the current path portion, including a second nitride-based semiconductor layer, while the current blocking layer is formed in the vicinity of the current path portion and a region having no current blocking layer is included in a region not in the vicinity of the current path portion. Thus, the width of the current blocking layer is reduced, whereby strain applied to the current blocking layer is relaxed. Consequently, the thickness of the current blocking layer can be increased, thereby stabilizing transverse light confinement.
    Type: Grant
    Filed: September 23, 2005
    Date of Patent: October 3, 2006
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Masayuki Hata, Yasuhiko Nomura, Daijiro Inoue
  • Patent number: 7116688
    Abstract: A laser system for generating at least one pulse and/or pulse sequence(s) of pulses having at least one specified property, such as pulse energy, duration, peak intensity, pulse form and/or timing includes an amplifying cavity. The amplification process is monitored in the amplifying cavity to obtain data about at least one property of the pulse sequence and/or the single pulse(s). The system also compares the obtained data with reference data and it controls at least one switching means for inputting, outputting and/or retaining the pulse(s) in the amplifying cavity such that at least one property of the pulse sequences and/or the pulses at an output of the laser system has substantially a specified value.
    Type: Grant
    Filed: August 6, 2003
    Date of Patent: October 3, 2006
    Assignee: 20/10 Perfect Vision Optische Geraete GmbH
    Inventors: Thomas Sauter, Leander Zickler
  • Patent number: 7116689
    Abstract: A method of evaluating a laser comprises providing a current into the laser and measuring a voltage output of an electroabsorptive modulator (EAM) coupled to the laser. A device under test includes a laser, and an electroabsorptive modulator (EAM), wherein said EAM monitors an output of said laser.
    Type: Grant
    Filed: August 16, 2002
    Date of Patent: October 3, 2006
    Inventor: Edward A. Pitman
  • Patent number: 7113532
    Abstract: A semiconductor laser device is one of AlGaInAs semiconductor laser devices, and has a multi-layer structure with a n-GaAs substrate on which a n-Al0.3Ga0.7As buffer layer, a n-Al0.47Ga0.53As clad layer, active layer portion, p-Al0.47Ga0.53As clad layer and p-GaAs cap layer are formed. The active layer portion is configured as a multi-layer structure including (Al0.37Ga0.63)0.97In0.03As light guide layer, Al0.1Ga0.9As active layer and (Al0.37Ga0.63)0.97In0.03As light guide layer. By using the AlGaInAs layer to which In is added is used as the light guide layers, the active layer is under compressive strain. Accordingly, the lattice constant of the active layer at the laser emitting edge becomes smaller due to a force from the adjacent light guide layers. The band gap energy of the active layer near the laser emitting edge becomes larger than the inside of laser device, thereby forming the window structure.
    Type: Grant
    Filed: April 25, 2003
    Date of Patent: September 26, 2006
    Assignee: Sony Corporation
    Inventors: Tsuyoshi Nagatake, Shoji Hirata
  • Patent number: 7113527
    Abstract: When CW laser is irradiated on a semiconductor film while being relatively scanned in a fabrication process of a semiconductor device, many crystal grains extending in a scanning direction are formed. The semiconductor film irradiated in this way has characteristics substantially approximate to those of a single crystal in the scanning direction. However, because productivity and uniformity of laser annealing are low, mass-production is difficult. A plurality of laser beams is processed into linear beams and is allowed to possess mutually superposing portions to form a more elongated linear beam and to thus improve productivity. The linear beams the overlapping to one another have a positional relation satisfying a predetermined limitation formula, and uniformity of laser annealing can be remarkably improved.
    Type: Grant
    Filed: December 20, 2002
    Date of Patent: September 26, 2006
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Koichiro Tanaka
  • Patent number: 7113530
    Abstract: In order to obtain a visually high quality image with excellent sharpness using a silver halide photosensitive material, it is necessary to reduce the ratio of EL light in the light output from a GaN based laser diode to 20% or less. For example, when the light intensity measured on a sheet of photosensitive paper is 0.05 mW, the thickness of a waveguide is 3 nm and the width of the waveguide is 3 ?m, this condition is satisfied with a length of a resonator being 1 mm or less. In other words, a waveguide width W1 and a resonator length L are set such that the product of the waveguide width W1 and the resonator length L (W1┬ĚL) becomes 0.003 mm2 or less. This reduces the output ratio of the EL light, and a high quality image with excellent sharpness can be obtained when a silver halide photosensitive material is exposed.
    Type: Grant
    Filed: December 27, 2002
    Date of Patent: September 26, 2006
    Assignees: Nichia Corporation, Fuji Photo Film Co., Ltd.
    Inventors: Kenji Matsumoto, Toshiro Hayakawa
  • Patent number: 7110428
    Abstract: A vertical cavity surface emitting laser, including an active region, an electrical contact for injecting current into the active region in order to generate photons, and an aperture between the active region and the contact for restricting current flow into the active region. The aperture is sufficiently large in at least one transverse dimension for the active region to support multiple transverse modes, and the aperture and contact are configured to produce current crowding in the active region. The direction of photon emission from the laser is determined by the injection current selectively stimulating different transverse modes.
    Type: Grant
    Filed: May 9, 2003
    Date of Patent: September 19, 2006
    Assignee: The Australian National University
    Inventors: Chennupati Jagadish, Michael Israel Cohen
  • Patent number: 7106765
    Abstract: A tuneable laser includes a gain section bounded at one end by a first reflector adapted to produce a comb of reflective peaks and on the other end by a second reflector in the form of a plurality of discrete grating units each capable of reflecting at one of the peaks of the comb, and each grating unit having at least two independently actuable electrodes, which when actuated independently one from the other is capable of reducing the reflectivity of the grating unit and in which at least two of the grating units have different pitches.
    Type: Grant
    Filed: September 12, 2002
    Date of Patent: September 12, 2006
    Assignee: Bookham Technology, plc
    Inventors: Andrew Carter, Douglas Reid
  • Patent number: 7106766
    Abstract: In a conventional optical device which mounts a semiconductor light emitting element, the processing is difficult and a manufacturing process cost is expensive because of the necessity of forming via holes in a substrate. An optical device comprises a laser diode which needs heat radiation, a glass substrate which is integrally molded into a mold glass for arranging the laser diode, a metallic heat sink arranged at an edge of the glass substrate for radiating heat generated from the laser diode, wherein an active layer proximity surface of the laser diode is arranged to oppose the heat sink, both of them are connected with a conductive paste through a lateral groove formed in the glass substrate.
    Type: Grant
    Filed: March 27, 2003
    Date of Patent: September 12, 2006
    Inventors: Kaoru Ishida, Tsuguhiro Korenaga