Patents Examined by Minsun Oh
  • Patent number: 7366211
    Abstract: A laser device which may be used as an oscillator or amplifier comprising a chamber having a volume formed therein and a gain medium within the volume. The gain medium comprises a solid-state element containing active laser ion within the volume. A cooling fluid flows about the solid-state element and a semiconductor laser diode provides optical pump radiation into the volume of the laser chamber such that laser emission from the device passes through the gain medium and the fluid. The laser device provides the advantages of a solid-state gain medium laser (e.g., diode-pumping, high power density, etc), but enables operation at higher average power and beam quality than would be achievable from a pure solid-state medium.
    Type: Grant
    Filed: September 5, 2006
    Date of Patent: April 29, 2008
    Assignee: General Atomics
    Inventors: Michael D. Perry, Paul S. Banks, Jason Zweiback, Robert W. Schleicher
  • Patent number: 7362789
    Abstract: A solid-state laser crystal constituting a laser-diode-excited solid-state laser apparatus or an optical fiber constituting a fiber laser apparatus or fiber laser amplifier is doped with one of Ho3+, Sm3+, Eu3+, Dy3+, Er3+, and Tb3+ so that a laser beam is emitted from the solid-state laser crystal or the optical fiber, or incident light of the fiber laser amplifier is amplified, by one of the transitions from 5S2 to 5I7, from 5S2 to 5I8, from 4G5/2 to 6H5/2, from 4G5/2 to 6H7/2, from 4F3/2 to 6H11/2, from 5D0 to 7F2, from 4F9/2 to 6H13/2, from 4F9/2 to 6H11/2, from 4S3/2 to 4I15/2, from 2H9/2 to 4I13/2, and from 5D4 to 7F5. The above solid-state laser crystal or optical fiber is excited with a GaN-based compound laser diode.
    Type: Grant
    Filed: September 30, 2004
    Date of Patent: April 22, 2008
    Assignee: FUJIFILM Corporation
    Inventors: Hisashi Ohtsuka, Yoji Okazaki, Takayuki Katoh
  • Patent number: 7362784
    Abstract: An object of the present invention is obtaining a semiconductor film with uniform characteristics by improving irradiation variations of the semiconductor film. The irradiation variations are generated due to scanning while irradiating with a linear laser beam of the pulse emission. At a laser crystallization step of irradiating a semiconductor film with a laser light, a continuous light emission excimer laser emission device is used as a laser light source. For example, in a method of fabricating an active matrix type liquid crystal display device, a continuous light emission excimer laser beam is irradiated to a semiconductor film, which is processed to be a linear shape, while scanning in a vertical direction to the linear direction. Therefore, more uniform crystallization can be performed because irradiation marks can be avoided by a conventional pulse laser.
    Type: Grant
    Filed: August 15, 2006
    Date of Patent: April 22, 2008
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Shunpei Yamazaki, Koichiro Tanaka
  • Patent number: 7362788
    Abstract: The present invention provides a semiconductor laser including a lower clad layer, an active layer including at least one quantum well layer, and an upper clad layer formed in this order above a semiconductor substrate, and having a window region including a portion in which the quantum well layer in the active layer and layers adjacent to the active layer are intermixed in the vicinity of a light emitting end face perpendicular to the surface of the semiconductor substrate, in which the lower clad layer has a refractive index higher than that of the upper clad layer, and the light intensity distribution in the window region spreads more widely in the direction perpendicular to the surface of the semiconductor substrate than the light intensity distribution in the gain region, and also provides a method for fabricating such a semiconductor laser.
    Type: Grant
    Filed: September 23, 2004
    Date of Patent: April 22, 2008
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Masanori Watanabe, Mitsuhiro Matsumoto, Tadashi Takeoka, Fumie Kunimasa
  • Patent number: 7362782
    Abstract: An optical semiconductor device includes a wavelength-tunable semiconductor laser chip, a mount carrier, a first temperature sensor and a wire. The wavelength-tunable semiconductor laser chip has a first optical waveguide and a second optical waveguide. The second optical waveguide has a heater on a surface thereof and is optically coupled to the first optical waveguide. The mount carrier is for mounting the wavelength-tunable semiconductor laser chip, and has a first area arranged at a surface of the mount carrier of the first optical waveguide side when the wavelength-tunable semiconductor laser chip is mounted. The first temperature sensor is mounted on the first area. The wire couples between the heater and a second area arranged at a surface of the mount carrier of the second optical waveguide side when the wavelength-tunable semiconductor laser chip is mounted.
    Type: Grant
    Filed: March 29, 2007
    Date of Patent: April 22, 2008
    Assignee: Eudyna Devices Inc.
    Inventors: Tsutomu Ishikawa, Takuya Fujii
  • Patent number: 7359414
    Abstract: A semiconductor laser light emitting circuit includes a semiconductor laser diode emitting a laser light by modulating a current supplied thereto, a light intensity detection circuit that detects the laser light and generates a voltage, and a voltage-current conversion circuit converting a voltage into a current supplied to the laser diode. A S/H capacitance is provided to store electric charge and output a voltage to the voltage/current conversion circuit. A first operational amplifier is provided to output a first current charging the S/H capacitance. A rapidly charging circuit is provided to charge the S/H capacitance with a second current. The rapidly charging circuit terminates charging when the voltage is equal to or more than a second reference voltage.
    Type: Grant
    Filed: October 25, 2004
    Date of Patent: April 15, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Junichi Ikeda, Hiroaki Kyougoku
  • Patent number: 7359413
    Abstract: A diode-pumped solid state laser, e.g., in a side-pumped or end-pumped configuration, including a lasing medium (30, 40, 62) comprising at least one surface (41) through which the laser is pumped, and at least one diamond plate (32, 42, 64) in thermal contact with the at least one surface (41). In an embodiment a plurality of segments of said lasing medium (62) are disposed in proximity to each other, and said at least one diamond plate (64) is disposed between two adjacent segments, and in thermal contact with said elements.
    Type: Grant
    Filed: April 1, 2003
    Date of Patent: April 15, 2008
    Assignee: Soreq Nuclear Research Center
    Inventors: Yitshak Tzuk, Alon Tal, Yaakov Glick, Yuval Isbi
  • Patent number: 7359423
    Abstract: A semiconductor laser includes an active layer on an n-type InP substrate. A diffraction grating and a p-type InP cladding layer are above the active layer. The diffraction grating has at least one phase shift portion. Facets of the distributed feedback laser each have thereon an antireflective film having a reflectance of 3% or less. The diffraction grating does not extend into end regions of the distributed feedback laser, each end region extending 1 ?m-20 ?m from a respective one of the facets toward an opposite end in a waveguide direction.
    Type: Grant
    Filed: January 25, 2005
    Date of Patent: April 15, 2008
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Yuichiro Okunuki
  • Patent number: 7358156
    Abstract: A method of manufacturing a compound semiconductor device comprises forming a scribed groove extending from an edge of a major surface of a laminated body to an internal region on the first major surface. The laminated body has the first major surface and a second major surface and is formed by crystal growth of a compound semiconductor multilayer film on a substrate. The scribed groove is shallow at the edge and deep in the internal region. The method may further comprise separating the laminated body into first and second portions separated by a separation plane including the scribed groove by applying load to the second major surface of the laminated body.
    Type: Grant
    Filed: March 16, 2006
    Date of Patent: April 15, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akira Tanaka, Masaaki Onomura, Seiji Iida, Takayuki Matsuyama
  • Patent number: 7358590
    Abstract: A semiconductor device includes a memory with a simple structure, an inexpensive semiconductor device, a manufacturing method and a driving method thereof. One feature is that, in a memory which has a layer including an organic compound as a dielectric, by applying a voltage to a pair of electrodes, the state change caused by the precipitous change in volume (such as bubble generation) is generated between the pair of electrodes. Short-circuiting between a pair of electrodes is promoted by acting force based on this state change. Concretely, a bubble generating area is provided in the memory element to generate a bubble between the first conductive layer and the second conductive layer.
    Type: Grant
    Filed: March 9, 2006
    Date of Patent: April 15, 2008
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Mikio Yukawa, Yoshinobu Asami, Ryoji Nomura
  • Patent number: 7359417
    Abstract: The invention has such a double hetero structure (11) that an active layer (3) is sandwiched by an n-type clad layer (2) and a p-type clad layer (4) on a semiconductor substrate (1) made of GaAs. In the p-type clad layer (4), for example, an n-type current constriction layer (6) consisting of at least two layers is provided in such a configuration that a first layer (6a) thereof closer to the active layer is made of a material having almost the same refractive index as the p-type clad layer and a second layer (6b) thereof farther from the active layer is made of a material having a smaller refractive index than the first layer (6a). By this configuration, a self-excitement type and high-power semiconductor laser can be obtained which operates in a stable manner up to a high power without generating a kink while being self-excited at a low power.
    Type: Grant
    Filed: July 12, 2004
    Date of Patent: April 15, 2008
    Assignee: Rohm Co., Ltd.
    Inventor: Takashi Kimura
  • Patent number: 7359421
    Abstract: A semiconductor material vertical cavity surface emitting laser for emitting narrow linewidth light comprising a compound semiconductor material substrate and pairs of semiconductor material layers in a first mirror structure on the substrate of a first conductivity type each differing from that other in at least one constituent concentration and each first mirror pair separated from that one remaining by a first mirror spacer layer with a graded constituent concentration. An active region on the first mirror structure has plural quantum well structures separated by at least one active region spacer layer and there is a second mirror structure on the active region similar to the first but of a second conductivity type. A pair of electrical interconnections is separated by said substrate, said first mirror structure, said active region and said second mirror structure.
    Type: Grant
    Filed: March 7, 2007
    Date of Patent: April 15, 2008
    Assignee: Mytek, LLC
    Inventors: Mary K. Brenner, Klein L. Johnson
  • Patent number: 7359422
    Abstract: A semiconductor laser device is provided, which comprises a semiconductor laser element having a light emission surface, a reflective member having a reflective surface, and a light diffusing member provided between the light emission surface and the reflective surface. The light emission surface and the reflective surface face each other so that an external resonance cavity is provided therebetween. Scattered light is emitted from the light diffusing member.
    Type: Grant
    Filed: November 17, 2004
    Date of Patent: April 15, 2008
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Tetsuya Fujitani
  • Patent number: 7356066
    Abstract: A solid body laser has a crystal disk forming its laser active medium. A flat side of the crystal disk is totally reflecting. A resonator mirror configuration includes a partially transparent end mirror and one or more folding mirrors, which are disposed with spatial separation from the crystal disk, and the optical axes of the mirrors extend in an inclined manner on the central axis of the crystal disk in such manner that the laser beam which is diffused inside the resonator mirror configuration impinges upon the folding mirror at an oblique angle.
    Type: Grant
    Filed: April 3, 2006
    Date of Patent: April 8, 2008
    Assignee: Rofin Sinar Laser GmbH
    Inventors: Klaus Ludewigt, Frank-Peter Grundmann
  • Patent number: 7356061
    Abstract: Provided is a multi-beam semiconductor laser designed to change a pitch between laser beams while eliminating the risks of crosstalk and power-down. Reflective mirrors are disposed at either end surface of the laser oscillating region in the active layer formed along the striped current path, a reflective mirror located at a front surface has a reflectance sufficiently high to prevent emission of a laser beam from the front surface, and a wavelength demultiplexer is disposed at a location in each of the plurality of laser oscillating regions so as to change the direction of propagation of only laser oscillating wavelength beams for emission from the laser oscillating regions. The above construction allows adjustment of a pitch between laser beams.
    Type: Grant
    Filed: December 23, 2004
    Date of Patent: April 8, 2008
    Assignee: Samsung Electronics Co., Ltd
    Inventor: Takashi Kondo
  • Patent number: 7356064
    Abstract: A fast current-controlled polarization switching VCSEL with two independent intra-cavity p-contact electrodes and two independent intra-cavity n-contact electrodes positioned along the four sides of the symmetric aperture such that there are two independent p- and n-contact pairs placed on opposite sides of the aperture in a non-overlapping configuration. The anisotropy resulting from the unidirectional current flow causes the light output to be polarized perpendicular to the direction of current flow. A VCSEL driver circuit switches the polarization state of the output light by using the two orthogonal pairs of non-overlapping intra-cavity contacted electrodes to change the direction of current flow into the VCSEL aperture by 90 degrees.
    Type: Grant
    Filed: March 21, 2006
    Date of Patent: April 8, 2008
    Assignee: Ziva, Inc.
    Inventors: Anis Husain, Ashok V. Krishnamoorthy
  • Patent number: 7356056
    Abstract: In a display device that displays a video by scanning coherent light across a screen, modulation at high speeds and gradation are necessary for a coherent light source. An oscillation wavelength of a semiconductor laser outputting the fundamental wave is changed at high speeds through the plasma effect induced by applying a pulse current to the coherent light source. A change of the wavelength causes the output of a higher harmonic generated in a light wavelength conversion element to change, and gradation is produced using such a change.
    Type: Grant
    Filed: January 26, 2005
    Date of Patent: April 8, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Toshifumi Yokoyama, Kazuhisa Yamamoto
  • Patent number: 7356057
    Abstract: A vertical cavity surface emitting laser (VCSEL) module that is configured to operate in a wide temperature range without severely minimizing its lifetime or requiring excessive drive current. The VCSEL portion of the VCSEL module is tuned to operate efficiently at a higher than normal temperature. In addition to the VCSEL, the VCSEL module includes a heater and a temperature sensor that are used to maintain a particular minimum temperature that is within the efficient operation range of the VCSEL. By maintaining a temperature that is within the efficient operation range, the VCSEL module reduces the current required to operate the VCSEL and extends the overall lifetime of the VCSEL. The additional components of the VCSEL module do not interfere in any way with the signal quality produced by the VCSEL.
    Type: Grant
    Filed: October 28, 2003
    Date of Patent: April 8, 2008
    Assignee: Finisar Corporation
    Inventors: Qing Deng, Ruldolf J. Hofmeister
  • Patent number: 7356058
    Abstract: An adaptive laser diode driver capable of driving various laser diode types as well different laser diodes from the same type, while ensuring optimal optical performance over the lifetime and temperature change of the diode. The driver adaptively changes the voltage level of input data signals to achieve full current switching as well as short rise time (tr) and fall time (tf) in extreme modulation conditions. This is preformed by constantly monitoring the output signal of a laser diode. Based on the monitored signal a modulation current is adjusted and in response the low level and high level of the input data signals are set. In accordance with one embodiment, the adaptive laser diode driver can be integrated in an optical line terminal (OLT) or an optical network unit (ONU) of a passive optical network (PON).
    Type: Grant
    Filed: December 29, 2005
    Date of Patent: April 8, 2008
    Assignee: Broadlight Ltd.
    Inventors: Asaf Koren, Offer Schwartsglass
  • Patent number: 7356065
    Abstract: A solid-state laser crystal constituting a laser-diode-excited solid-state laser apparatus or an optical fiber constituting a fiber laser apparatus or fiber laser amplifier is doped with one of Ho3+, Sm3+, Eu3+, Dy3+, Er3+, and Tb3+ so that a laser beam is emitted from the solid-state laser crystal or the optical fiber, or incident light of the fiber laser amplifier is amplified, by one of the transitions from 5S2 to 5I7, from 5S2 to 5I8, from 4G5/2 to 6H5/2, from 4G5/2 to 6H7/2, from 4F3/2 to 6H11/2, from 5D0 to 7F2, from 4F9/2 to 6H13/2, from 4F9/2 to 6H11/2, from 4S3/2 to 4I15/2, from 2H9/2 to 4I13/2, and from 5D4 to 7F5. The above solid-state laser crystal or optical fiber is excited with a GaN-based compound laser diode.
    Type: Grant
    Filed: September 30, 2004
    Date of Patent: April 8, 2008
    Assignee: FUJIFILM Corporation
    Inventors: Hisashi Ohtsuka, Yoji Okazaki, Takayuki Katoh