Patents Examined by Marcia A. Golub
  • Patent number: 7924898
    Abstract: One facet and the other facet of a nitride based semiconductor laser device are respectively composed of a cleavage plane of (0001) and a cleavage plane of (000 1). Thus, the one facet and the other facet are respectively a Ga polar plane and an N polar plane. A portion of the one facet and a portion of the other facet, which are positioned in an optical waveguide, constitute a pair of cavity facets. A first protective film including oxygen as a constituent element is formed on the one facet. A second protective film including nitrogen as a constituent element is formed on the other facet.
    Type: Grant
    Filed: September 24, 2008
    Date of Patent: April 12, 2011
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Shingo Kameyama, Yasuhiko Nomura, Ryoji Hiroyama, Masayuki Hata
  • Patent number: 7920609
    Abstract: In an exposure device comprising a laser controller that is configured as a circuit board capable of independently being changed, and that controls the emission of laser light from a laser emitter emitting laser light on receipt of an instruction for control given from a main controller responsible for overall control of the operation of the exposure device, error control information that is obtained in advance with regard to the circuit board and controls variations of a controlling factor due to a circuit error of the circuit board is stored into a memory provided to the laser controller prior to the provision of the circuit board to the exposure device. On receipt of an instruction for control given from the main controller to cause the emission of laser light in a predetermined amount of light, the laser controller determines a condition of emission of laser light based on the error control information stored in the memory to cause the laser emitter to emit laser light under the condition of emission.
    Type: Grant
    Filed: April 18, 2008
    Date of Patent: April 5, 2011
    Assignee: Dainippon Screen Mfg. Co., Ltd.
    Inventors: Toshimitsu Hamagishi, Mamoru Fujimoto
  • Patent number: 7907647
    Abstract: The present invention relates to an optical element for converting light of prescribed wavelength emitted from a light source into light of wavelength different from the prescribed wavelength for outputting. A first crystal part (20) and a second crystal part (21) having respective surfaces opposed to each other whose coefficients of linear expansion are different by 5 ppm or more are optically polished so that the surfaces opposed to each other include crystallographic axes. An acrylic adhesive whose glass transition point is 75° C. or lower is applied to the adhesive surface of the first crystal part (20) or the second crystal part (21) to stick the first crystal part (20) and the second crystal part (21) to each other. The adhesive is irradiated with light to cure the adhesive and form an adhesive layer (22) having a refractive index of 1.52 or lower. Then, the first crystal part and the second crystal part stuck to each other are cut into a desired size to form the optical element.
    Type: Grant
    Filed: June 18, 2003
    Date of Patent: March 15, 2011
    Assignee: Sony Corporation
    Inventors: Koichiro Kezuka, Hiroto Sasaki
  • Patent number: 7889774
    Abstract: The present invention relates to organic lasers. More specifically, the present invention is directed to an organic laser that provides a self-stimulated source of coherent radiation originating from organic microcavity polaritons. The organic polariton laser of the present invention comprises a substrate, a resonant microcavity comprising an organic polariton emission layer; and an optical pump. In preferred embodiments the optical pump is a microcavity OLED allowing for the fabrication of a self-contained or integrated device.
    Type: Grant
    Filed: June 25, 2004
    Date of Patent: February 15, 2011
    Assignee: The Trustees of Princeton University
    Inventors: Stephen R. Forrest, Russell Holmes
  • Patent number: 7881355
    Abstract: Laser modules using two-dimensional laser diode arrays are combined to provide an intense laser beam. The laser diodes in a two-dimensional array are formed into rows and columns, and an optical assembly images light generated by laser diodes in a column into an optical fiber. The laser light outputs of the laser modules are combined by a spectral combiner into an optical fiber to form an intense laser beam.
    Type: Grant
    Filed: December 15, 2005
    Date of Patent: February 1, 2011
    Assignee: Mind Melters, Inc.
    Inventor: Donald L. Sipes, Jr.
  • Patent number: 7881349
    Abstract: An optically pumped semiconductor-laser (OPS-laser) resonator includes an arrangement for delivering optical pump radiation on an OPS-chip to cause fundamental radiation to circulate in the resonator. The resonator includes second and third-harmonic generating crystals and is arranged deliver third-harmonic radiation. The resonator also includes a stop positioned and configured to stabilize the laser output. The pump radiation arrangement delivers the pump radiation at an angle to the resonator axis and includes wedged GRIN lens arranged such that the pump radiation forms a circular spot on the OPS chip. The third harmonic generating crystal acts as a polarizer for the fundamental radiation and angularly separates fundamental and third harmonic beams.
    Type: Grant
    Filed: January 29, 2008
    Date of Patent: February 1, 2011
    Assignee: Coherent, Inc.
    Inventors: Christopher Ihli, Qi-Ze Shu, Andrea Caprara, Juan L. Chilla
  • Patent number: 7876802
    Abstract: The present invention describes an optically end-pumped laser gain module, comprising a gain medium which is pumped by a light beam that has a larger size on the input face of the medium than on its output face.
    Type: Grant
    Filed: August 10, 2004
    Date of Patent: January 25, 2011
    Assignee: Lumera Laser GmbH
    Inventor: Louis McDonagh
  • Patent number: 7869474
    Abstract: An apparatus comprising a laser source configured to emit a light beam along a first path, an optical beam steering component configured to steer the light beam from the first path to a second path at an angle to the first path, and a diffraction grating configured to reflect back at least a portion of the light beam along the second path, wherein the angle determines an external cavity length. Included is an apparatus comprising a laser source configured to emit a light beam along a first path, a beam steering component configured to redirect the light beam to a second path at an angle to the first path, wherein the optical beam steering component is configured to change the angle at a rate of at least about one Kilohertz, and a diffraction grating configured to reflect back at least a portion of the light beam along the second path.
    Type: Grant
    Filed: January 7, 2009
    Date of Patent: January 11, 2011
    Assignee: William Marsh Rice University
    Inventors: Gerard Wysocki, Frank K. Tittel
  • Patent number: 7843982
    Abstract: A method of avoiding device failure caused by facet heating is described. The method is particularly applicable to a semiconductor laser. In the method, a semiconductor laser facet including GaAsN is hydrogenated such that the bandgap within the facet is greater than the bandgap in the active region of the InGaAsN laser. The increased bandgap reduces absorption of light in the facet and the associated heating that results.
    Type: Grant
    Filed: December 15, 2005
    Date of Patent: November 30, 2010
    Assignee: Palo Alto Research Center Incorporated
    Inventors: Christopher L. Chua, Michael A. Kneissl, Noble M. Johnson, Peter Kiesel
  • Patent number: 7830940
    Abstract: A nitride semiconductor laser element comprises a nitride semiconductor substrate and a nitride semiconductor layer laminated thereon, wherein the nitride semiconductor substrate has a high dislocation density region and a low dislocation density region containing lower dislocation than that of the high dislocation density region, and has at least one recess formed in at least the high dislocation density region, the nitride semiconductor layer has a first nitride semiconductor layer in which the grown film thickness in the lateral direction from the side faces of the recess in the substrate is greater than the grown film thickness in the heightwise direction from a region other than the recess, and a second nitride semiconductor layer that is disposed on the first nitride semiconductor layer and contains indium, and the first nitride semiconductor layer and second nitride semiconductor layer have recess over the recess in the nitride semiconductor substrate.
    Type: Grant
    Filed: September 4, 2007
    Date of Patent: November 9, 2010
    Assignee: Nichia Corporation
    Inventors: Shingo Masui, Tomonori Morizumi
  • Patent number: 7826512
    Abstract: It is an object of the present invention to provide a semiconductor laser device with high-yielding in which a clack generated in an epitaxial growth layer is restrained and to the manufacturing method thereof, the semiconductor laser device includes a GaN substrate 1, an n-type GaN layer 2, an n-type AlGaN cladding layer 3, a n-type GaN guide layer 4, an InGaN multiple quantum well active layer 5, an undoped-GaN guide layer 6, a p-type AlGaN electron overflow suppression layer 7, a p-type GaN guide layer 8, a SiO2 blocking layer 9, an Ni/ITO cladding layer electrode 10 as a transparent electrode, a Ti/Au pad electrode 11, and a Ti/Al/Ni/Au electrode 12. The SiO2 blocking layer 9 is formed above the InGaN multiple quantum well active layer 5 so as to have an opening. The Ni/ITO cladding layer electrode 10 is formed inside the opening, and which is transparent for the light from the InGaN multiple quantum well active layer, and serves as a cladding layer.
    Type: Grant
    Filed: September 5, 2007
    Date of Patent: November 2, 2010
    Assignee: Panasonic Corporation
    Inventors: Tetsuzo Ueda, Masaaki Yuri
  • Patent number: 7826507
    Abstract: A semiconductor light-emitting device includes a light generation unit generating light with an oscillation wavelength ?, a light outgoing facet from which light generated at the light generation unit emerges, a light reflecting facet at which light generated at the light generation unit is reflected, and a high reflection film at the light reflecting facet and made of a dielectric multilayered film of at least three layers. The high reflection film includes a first layer which is in contact with the light reflection facet, is constituted of Al2O3, and has a thickness smaller than ?/4n, wherein n is the refractive index of Al2O3, a second layer which is in contact with the first layer, and a third layer which is in contact with the second layer and has a refractive index different from the refractive index of the second layer.
    Type: Grant
    Filed: January 30, 2008
    Date of Patent: November 2, 2010
    Assignee: Mitsubishi Electric Corporation
    Inventors: Harumi Nishiguchi, Hiromasu Matsuoka, Yasuyuki Nakagawa, Yasuhiro Kunitsugu
  • Patent number: 7817702
    Abstract: Unidirectionality of lasers is enhanced by forming one or more etched gaps (78, 80) in the laser cavity. The gaps may be provided in any segment of a laser, such as any leg of a ring laser, or in one leg (62) of a V-shaped laser (60). A Brewster angle facet at the distal end of a photonic device coupled to the laser reduces back-reflection into the laser cavity. A distributed Bragg reflector is used at the output of a laser to enhance the side-mode suppression ratio of the laser.
    Type: Grant
    Filed: March 18, 2004
    Date of Patent: October 19, 2010
    Assignee: Binoptics Corporation
    Inventors: Alex A. Behfar, Alfred T. Schremer, Jr., Cristian B. Stagarescu
  • Patent number: 7812520
    Abstract: The conventional light-emitting element formed by an electroluminescent material has a problem due to poor color purity of light emission. Accordingly, it is an object of the present invention to provide a high luminance and high efficiency light-emitting device formed by an organic compound material. The invention provides a light-emitting device in which an organic compound layer that emits light having an emission peak with a half-band width of at most 10 nm upon applying current is interposed between a pair of electrodes is provided. The variation of emission peak intensity depending on a current density can be sorted by two linear regions with different gradients. A region of a sharp gradient is at a higher current density side compared to a region of a slow gradient. TFTs are provided to each pixel in order to perform active matrix driving.
    Type: Grant
    Filed: June 16, 2008
    Date of Patent: October 12, 2010
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Ryoji Nomura, Hiroko Abe, Mikio Yukawa, Shunpei Yamazaki
  • Patent number: 7759693
    Abstract: The present invention is directed to photonic devices which emit or absorb light with a wavelength shorter than that GaN photonic devices can emit or absorb. The devices according to the present invention are formed using molybdenum oxide of a high purity as a light emitting region or a light absorbing region. New inexpensive photonic devices which emit light with a wavelength from blue to deep ultraviolet rays are realized. The devices according to the present invention can be formed at a temperature relating low such as 700° C.
    Type: Grant
    Filed: May 19, 2004
    Date of Patent: July 20, 2010
    Inventor: Takashi Katoda
  • Patent number: 7760774
    Abstract: A laser device with frequency conversion, the device comprising a complex optical cavity comprising two cavity parts with two different levels of circulating intracavity power wherein there is placed at least one non-linear crystal (30) is placed within the cavity part of higher circulating power and an active medium (21) in the cavity part of lower circulating power, the power enhancement achieved in two steps and the total enhancement being the product of the enhancement factors in each step, providing additional freedom in design allowing both the condition for high enhancement of the interacting laser power inside the intracavity non-linear crystal and the condition for maximum power output from the laser to be satisfied simultaneously and wherein said complex optical cavity the first cavity part provides the initial step of power enhancement and comprises at least a laser cavity back mirror (20), highly reflective about a laser radiation fundamental frequency ?, and an active (gain) medium.
    Type: Grant
    Filed: September 20, 2002
    Date of Patent: July 20, 2010
    Assignee: Klastech-Karpushko Laser Technologies GmbH
    Inventor: Fedor V. Karpushko
  • Patent number: 7697580
    Abstract: A power monitoring and correction to a desired power level of a laser or group of lasers utilizes two photodetectors which are employed to accurately determine the amount of output power from the front end or “customer” end of a laser or a plurality of such lasers. During power detection, which may be accomplished intermittently or continuously, the laser is modulated with a tone of low frequency modulation. One photodetector at the rear of the laser is employed to detect the DC value of the frequency tone, i.e., a value or number representative of the AC peak-to-peak swing, amplitude or modulation depth of the tone. Also, the rear photodetector may be employed to determine the optical modulation index (OMI). In either case, these values may be employed in a closed loop feedback system to adjust or otherwise calibrate the value of the low tone frequency relative to the total desired bias current applied to the laser.
    Type: Grant
    Filed: October 8, 2004
    Date of Patent: April 13, 2010
    Assignee: Infinera Corporation
    Inventors: Robert W. Smith, Alan C. Nilsson
  • Patent number: 7693206
    Abstract: This invention relates to semiconductor laser apparatus with a structure for reducing the divergence angle of output light and for narrowing the spectral width. The semiconductor laser apparatus has at least a semiconductor laser array, a collimator lens, a path rotator, and an optical element with a reflecting function. The collimator lens collimates a plurality of laser beams from the semiconductor laser array, in a predetermined direction. The path rotator outputs each beam collimated in the predetermined direction, with a predetermined divergence angle in the predetermined direction in a state in which a transverse section of the beam is rotated by about 90°. The optical element is arranged at a position where at least a part of each beam from the path rotator arrives, and constitutes at least a part of an external resonator. This optical element reflects a part of each beam from the path rotator to return the reflected part of each beam to the active layer in the semiconductor laser array.
    Type: Grant
    Filed: May 7, 2004
    Date of Patent: April 6, 2010
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Yujin Zheng, Hirofumi Kan, Xin Gao
  • Patent number: 7680163
    Abstract: A first mirror (5) that can be located at a reflection position (I) at which an optical path is blocked and a laser beam (a) is reflected, and a second mirror (6) that reflects the laser beam (a) which is reflected by the first mirror (5) are disposed between the condenser lens (2) and the object to be irradiated (4). The first mirror (5) is located at the reflection position (I) so that the laser beam (a) that is transmitted through the condenser lens (2) is sequentially reflected by the first and second mirrors (5 and 6), and an intensity of the laser beam (a) that is again reflected by the first mirror (5) is made to coincide with an intensity of the laser beam (a) that is reflected from the object to be irradiated (4), and the condenser lens (2) is heated in the same manner that the processing laser beam (a) is transmitted through the condenser lens (2) and irradiated on the object to be irradiated (4).
    Type: Grant
    Filed: September 12, 2008
    Date of Patent: March 16, 2010
    Assignee: The Japan Steel Works, Ltd.
    Inventors: Junichi Shida, Suk-hwan Chung, Shuichi Uryu
  • Patent number: 7675951
    Abstract: A semiconductor laser driving apparatus controls a semiconductor laser to output a prescribed intensity of laser light. The semiconductor laser driving apparatus includes at least two semiconductor laser driving circuits each outputting a prescribed amount of current to the semiconductor laser when operated, and a control circuit selectively transmitting a control signal and controlling one or more semiconductor laser driving circuits to operate in accordance with a prescribed intensity of laser light to be irradiated from the semiconductor laser.
    Type: Grant
    Filed: June 16, 2004
    Date of Patent: March 9, 2010
    Assignee: Ricoh Company, Ltd.
    Inventor: Yasukazu Nakatani