Patents Examined by Minsun Oh
  • Patent number: 7242706
    Abstract: A method and apparatus for producing molecular oxygen in the excited singlet delta oxygen electronic state for use as an excited species reactant in a chemical laser. Flowtubes defined by permeable membranes are used to mix the gas and liquid phase reactants to generate singlet delta oxygen and also to separate the generated singlet delta oxygen from the liquid phase products and reactants thereby eliminating liquid reactant carryover.
    Type: Grant
    Filed: October 20, 2004
    Date of Patent: July 10, 2007
    Assignee: The Boeing Company
    Inventor: Brady M. Schroeder
  • Patent number: 7242702
    Abstract: Lasing at the edge of the reflection band or at a defect state within the reflection band of a thin one-dimensional feedback structure is used to create a large-area, thin-film laser source with transverse dimensions that can be much greater than the film thickness. Angular confinement of radiation propagating perpendicular to the layers leads to a spreading of the beam inside the medium which is much greater than the diffraction divergence. This enhances the spatial extent of correlation at the output surface of the thin film. When a pump source induces gain at the lasing threshold in a wide region, a spatially coherent monochromatic light beam is emitted perpendicular to the film surface from the entire gain region. Alternate embodiments of the present invention include a passive spatial filter and an active amplifier.
    Type: Grant
    Filed: January 2, 2004
    Date of Patent: July 10, 2007
    Assignee: Chiral Photonics, Inc.
    Inventors: Victor Il'ich Kopp, Zhao-Qing Zhang, Azriel Zelig Genack
  • Patent number: 7239655
    Abstract: A compact high power laser dazzling device includes at least one heat sink, multiple laser resonators and an optical head. Each of the laser resonators extends axially from a first end, fixedly mounted to the heat sink, to a second end emitting an individual laser beam. The optical head is disposed adjacent to the second ends of the laser resonators and includes an optical transmission assembly that directs the individual laser beams of the laser resonators to define a region of overlap at a remote point a predetermined distance from the optical head. A laser beam intensity adjuster assembly may be disposed adjacent the output end of the optical head. The laser beam intensity adjuster assembly includes a front face having multiple apertures. At least one of the apertures has a holographic diffuser element mounted therein and at least one of the apertures has an optically clear window element or no optical elements mounted therein.
    Type: Grant
    Filed: April 6, 2006
    Date of Patent: July 3, 2007
    Inventor: Titus A. Casazza
  • Patent number: 7236504
    Abstract: A method of operating a stretched-pulse Raman fiber laser includes producing laser radiation gain in a laser cavity using predominantly Raman amplification. Such a stretched-pulse Raman fiber laser has a laser cavity that includes a Negative Group Velocity Dispersion Fiber connected in series with a Positive Group Velocity Dispersion Fiber, a polarization controller and an isolator. In some examples, the Negative Group Velocity Dispersion Fiber is a Dispersion Compensating Fiber. In other examples, the Negative Group Velocity Dispersion Fiber is replaced by a Raman Specialty Fiber.
    Type: Grant
    Filed: January 7, 2005
    Date of Patent: June 26, 2007
    Assignee: General Instrument Corporation
    Inventor: Shamino Y. Wang
  • Patent number: 7236505
    Abstract: A Fabry-Perot laser generates a mode-locked channel having the same wavelength as that of light injected into the laser. The laser includes a semiconductor substrate and a lower cladding layer formed on the substrate. An active layer is formed on the lower cladding layer and has a band gap distribution that continuously varies in a longitudinal direction of the substrate. The laser further includes an upper cladding layer formed on the active layer and the lower cladding layer.
    Type: Grant
    Filed: March 5, 2004
    Date of Patent: June 26, 2007
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Shi-Yun Cho
  • Patent number: 7233611
    Abstract: A conventional method for a solid-state laser device that obtains a laser beam output of a high quality at a high output using a laser diode as a pumping light source has a problem that the costs are increased and the fabrication becomes complicated due to an increasing number of components, such as a diffusing reflection mirror, a condenser lens, and a holding mechanism and a cooling mechanism thereof. Coating with a antireflection coating to reduce a transmission loss of laser diode light, and coating with a high reflection coating to reflect the laser diode light are provided alternately on the outer surface of a cooling tube. Also, an irradiation direction of the laser diode is not directed to the center of the laser rod, but is given with a certain angle to be positively tilted. This configuration makes it possible to eliminate the above problem.
    Type: Grant
    Filed: November 19, 2003
    Date of Patent: June 19, 2007
    Assignee: Laserfront Technologies, Inc.
    Inventors: Katsuji Mukaihara, Masaki Tsunekane
  • Patent number: 7233606
    Abstract: A pulsed fiber laser and associated electronics contained in a miniature package is disclosed. The Pulsed Fiber Laser Source (PFLS) can be a single-stage high gain master oscillator power amplifier (MOPA) type fiber laser source. The PFLS can include a distributed feedback (DFB) laser, a narrowband optical filter, a broad area high-power pump diode, and Erbium/Ytterbium (Er/Yb) double cladding doped fiber. Input electrical pulses drive the DFB laser diode to emit optical pulses that are then amplified by the optical amplifier. Active and passive cooling elements may be incorporated for continuous operation without rest time. Passive cooling for intermittent pulsed applications allows the laser source to be miniaturized by eliminating active cooling elements and associated power supplies and controllers. Low duty cycle relaxes drive requirements and further reduces the size.
    Type: Grant
    Filed: June 14, 2004
    Date of Patent: June 19, 2007
    Assignee: Cubic Corporation
    Inventors: Deepak Varshneya, John Roes, Tony Maryfield, Mike Roes, Lew Goldberg, Jean Marc Delavoux, Gabor Kulcsar
  • Patent number: 7233608
    Abstract: A frequency-stabilized laser source that is adapted for use as a frequency standard. The frequency of the laser source is locked and the laser beam delivered by the laser source on a transition of an absorber chemical element. The technique combines both operation with saturated absorption and synchronous detection, based on modulating said transition being saturated by the beam passing through the absorber chemical element. This produces a single frequency laser beam whose output frequency is stationary. The frequency is not continuously modulated and is more precise than that which would be obtained operating with single-pass absorption only. The laser source is thus adapted for making a frequency standard.
    Type: Grant
    Filed: June 18, 2002
    Date of Patent: June 19, 2007
    Assignee: Universite des Sciences et Technologies de Lille
    Inventors: Jaouad Zemmouri, Igor Razdobreev, Jean Ringot
  • Patent number: 7230966
    Abstract: An injection locking type or MOPA type of laser device capable of always providing stable output energy and wavelength is provided. For this purpose, the laser device includes an oscillator for exciting laser gas by oscillator discharge and oscillating seed laser light with band-narrowed wavelength, an amplifier for amplifying the seed laser light by amplification discharge to emit amplified laser light, a delay circuit for setting at least one of a delay time from light emission of the seed laser light to light emission of the amplified laser light, and a delay time from start of the oscillator discharge to start of the aforementioned amplification discharge, and a delay time compensation circuit for performing compensation of the delay circuit so that the delay time becomes an optimal delay time.
    Type: Grant
    Filed: August 29, 2005
    Date of Patent: June 12, 2007
    Assignee: Komatsu, Ltd.
    Inventors: Kiyoharu Nakao, Yoshifumi Ueno
  • Patent number: 7230965
    Abstract: Electrodes for a fluorine gas discharge laser are disclosed which may comprise a crown straddling the centerline axis between the pair of side walls and the pair of end walls, comprising a first material, forming at least a portion of the discharge region of the electrode; the crown in traverse cross section having the shape of the upper half of a canted ellipse rotated in the preionizer direction, such that a tangent to the short centerline axis of the ellipse forms an angle with the horizontal. Another embodiment may comprise an anode blade having a top portion and a first and second sidewall portion each intersecting the top portion; the anode blade being formed with the shape in cross section of the top portion being curvilinear and intersecting the generally straight potions of each of first and second sidewall portions along a radius of curvature and with the top portion beveled away from an asymmetric discharge side of the anode.
    Type: Grant
    Filed: September 26, 2003
    Date of Patent: June 12, 2007
    Assignee: Cymer, Inc.
    Inventors: Timothy S. Dyer, Richard G. Morton, Walter D. Gillespie, Thomas D. Steiger
  • Patent number: 7230963
    Abstract: A monolithic wavelength stabilized system comprises a laser monolithically formed with a waveguide splitter having at least two branches. Non-identical resonators having different wavelengths are operatively coupled to each branch of the splitter and a photodiode is communicatively coupled to receive the output from each non-identical resonator. A control unit receives the photocurrent outputs from the photodiodes, determines based on the photocurrents whether the wavelength of the laser signal is at a desired value, and transmits a feedback signal to the laser to move the laser output toward the desired wavelength. The laser, splitter, resonators, and photodiodes are monolithically formed in a single chip using asymmetric waveguides.
    Type: Grant
    Filed: April 14, 2005
    Date of Patent: June 12, 2007
    Assignee: The Trustees of Princeton University
    Inventors: Vinod M. Menon, Shubhashish R. Datta, Stephen R. Forrest
  • Patent number: 7227881
    Abstract: A Master Oscillator (MO)—Power Amplifier (PA) configuration (MOPA) can be used advantageously in an excimer laser system for micro-lithography applications, where semiconductor manufacturers demand powers of 40 W or more in order to support the throughput requirements of advanced lithography scanner systems. A MOPA-based laser system can provide both high pulse energies and high spectral purity. A MOPA system can utilize a multi-pass PA, as well as a special beam path capable of reducing the amount of ASE (Amplified Spontaneous Emission) and feedback to the MO. Lithography scanner optics are primarily fused silica, such that the peak pulse power must be kept low to avoid material compaction when a MOPA system is used with lithography applications. This conflict between the demand for high average power and the low peak power requirement of the pulsed excimer laser source can be resolved by using a novel beam path to generate a sufficiently long pulse length.
    Type: Grant
    Filed: March 9, 2006
    Date of Patent: June 5, 2007
    Assignee: Lambda Physik AG
    Inventors: Sergei V. Govorkov, Rainer Paetzel
  • Patent number: 7227879
    Abstract: A nitride semiconductor laser including a laminate that includes an n-side semiconductor layer, an active layer and a p-side semiconductor layer, the n-side semiconductor layer or p-side semiconductor layer including a current blocking layer 30 that is made of InxAlyGa1-x-yN (0?x?0.1, 0.5?y?1, 0.5?x+y?1) and has a stripe-shaped window 32 formed therein to pass current flow.
    Type: Grant
    Filed: June 28, 2004
    Date of Patent: June 5, 2007
    Assignee: Nichia Corporation
    Inventors: Hiroaki Matsumura, Tomoya Yanamono
  • Patent number: 7224707
    Abstract: A novel Q-switch device enables significant quality and value improvement for a Q-switched laser system by achieving a significant reduction of mode-beating noise during the pulsed output. The origin of mode-beating noise in a Q-switched laser is a result of high gain availability and amplification of competing standing-waves in formation, whose optical frequency is a product of natural selection via spatial hole burning in the gain medium. The novel Q-switch device employs an active, electro-optics or acousto-optics, Q-switch in combination with a saturable absorber device, to provide an optimized soft opening of the optical path and a controlled timing of a Q-switched laser. This novel combination offers larger modulation loss than otherwise possible with the active modulator alone, and it allows for higher gain build-up and energy extraction efficiency.
    Type: Grant
    Filed: March 5, 2004
    Date of Patent: May 29, 2007
    Inventor: Denis J. Gendron
  • Patent number: 7224708
    Abstract: Platinum (Pt) thin film heaters are deposited by a focused ion beam for semiconductor manufacturing of thermally tunable distributed feedback lasers. An exemplar 1.3 ?m InGaAsP/InP laser is integrated with a tuning element having a wide wavelength tuning range of 4.9 nm, that is, 857 GHz, with a small heater current of 13.0 mA.
    Type: Grant
    Filed: August 30, 2004
    Date of Patent: May 29, 2007
    Assignee: The Aerospace Corporation
    Inventors: Yongkun Sin, Nathan Presser
  • Patent number: 7221690
    Abstract: This specification relates to a semiconductor laser in which an n-type semiconductor layer (13), an active layer (101), and a p-type semiconductor layer (24) are stacked in this order on a substrate (11), the active layer (101) comprising a well layer composed of InGaN, the semiconductor laser comprising an intermediate layer (21) sandwiched between the active layer (101) and the p-type semiconductor layer (24), and the intermediate layer including no intentionally added impurities and being composed of a gallium nitride-based compound semiconductor. This semiconductor laser has an extended lifetime under high optical output power conditions.
    Type: Grant
    Filed: August 20, 2003
    Date of Patent: May 22, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yoshiaki Hasegawa, Toshiya Yokogawa
  • Patent number: 7221693
    Abstract: Exemplary embodiments of the present invention include surface-emitting type semiconductor lasers including photodetector sections, which have a degree of freedom in designing its structure and are capable of high-speed driving. A surface-emitting type semiconductor laser in accordance with exemplary embodiments the present invention includes a light emitting element section, and a photodetector section that is provided above the light emitting element section and includes an emission surface. The light emitting element section includes a first mirror, an active layer provided above the first mirror, and a second mirror provided above the active layer. The second mirror is formed from a first region and a second region. The second region contacts the photodetector section, and the second region has a resistance greater than a resistance of the first region.
    Type: Grant
    Filed: August 5, 2004
    Date of Patent: May 22, 2007
    Assignee: Seiko Epson Corporation
    Inventor: Tsuyoshi Kaneko
  • Patent number: 7221692
    Abstract: A semiconductor laser device comprises: a cladding layer of a first conductivity type; an active layer provided on the cladding layer; and a cladding layer of a second conductivity type provided on the active layer. At least a part of the cladding layer of the second conductivity type has a ridge stripe. The ridge stripe includes: an upper part having substantially vertical sidewalls; and a lower portion having sidewalls inclined so that the stripe becomes wider toward the active layer.
    Type: Grant
    Filed: May 13, 2004
    Date of Patent: May 22, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akira Tanaka, Yoshiyuki Itoh, Osamu Horiuchi, Akio Makuta, Koichi Gen-Ei, Hideo Shiozawa
  • Patent number: 7218655
    Abstract: A temperature insensitive diode-pumped solid state laser is disclosed in this invention. The components of the laser are optimized with temperature insensitive design, making the laser capable of operating in a wide temperature range without using any cooling/heating system to maintain the temperature of its components.
    Type: Grant
    Filed: October 7, 2005
    Date of Patent: May 15, 2007
    Assignee: B&W Tek Property, Inc.
    Inventors: Sean Xiaolu Wang, Qun Li, Rongsheng Tian
  • Patent number: 7218653
    Abstract: An ultraviolet laser is provided that increases the conversion efficiency of laser beams when harmonics having wavelengths of less than 355 nm are generated by converting laser beams with a wavelength conversion element made of a single crystal of lithium tetraborate. A wavelength conversion element is heated and controlled to a specific temperature (for example, 200° C.) within a temperature range of 200 to 450° C. with a predetermined temperature precision.
    Type: Grant
    Filed: September 9, 2004
    Date of Patent: May 15, 2007
    Assignee: Mitsubishi Materials Corporation
    Inventors: Genta Masada, Hiroyuki Shiraishi, Ichiro Sekine