Grating Patents (Class 372/102)
  • Patent number: 9209592
    Abstract: Embodiments described herein include a system for producing ultrashort tunable pulses based on ultra broadband OPA or OPG in nonlinear materials. The system parameters such as the nonlinear material, pump wavelengths, quasi-phase matching periods, and temperatures can be selected to utilize the intrinsic dispersion relations for such material to produce bandwidth limited or nearly bandwidth limited pulse compression. Compact high average power sources of short optical pulses tunable in the wavelength range of 1800 to 2100 nm and after frequency doubling in the wavelength range of 900 to 1050 nm can be used as a pump for the ultra broadband OPA or OPG. In certain embodiments, these short pump pulses are obtained from an Er fiber oscillator at about 1550 nm, amplified in Er fiber, Raman-shifted to 1800 to 2100 nm, stretched in a fiber stretcher, and amplified in Tm-doped fiber.
    Type: Grant
    Filed: December 14, 2012
    Date of Patent: December 8, 2015
    Assignee: IMRA AMERICA, INC.
    Inventors: Gennady Imeshev, Martin E. Fermann
  • Patent number: 9172212
    Abstract: A tunable LD with reduced number of the butt joint is disclosed. The tunable LD includes the reflector and a waveguide core. The reflector includes a plurality of segments each having a grating region and a space region adjacent to the grating region. The waveguide core includes a gain region extending in two segments adjacent to each other and a tuning region extending in two segments adjacent to each other and also adjacent to the segment for the gain region.
    Type: Grant
    Filed: May 25, 2011
    Date of Patent: October 27, 2015
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Toshimitsu Kaneko
  • Patent number: 9170410
    Abstract: A laser microscope (10) having a laser light source (22) which generates laser light pulses (23) for the purpose of examining a sample (16). An optical element (25) is arranged in the beam path of the laser light pulses (23). The optical element (25) disperses the wavelength spectrum of the laser light pulses (23). Fractions (46, 48, 60, 62) of the broad-band laser light pulses (32) having different wavelengths travel different path lengths upon passing through a compensation device (30), such that the different fractions (46, 48, 60, 62) arrive at the sample (16) at the same time.
    Type: Grant
    Filed: August 26, 2011
    Date of Patent: October 27, 2015
    Assignee: Leica Microsystems CMS GmbH
    Inventor: Frank Schreiber
  • Patent number: 9160455
    Abstract: An external cavity laser array system may be used in a WDM optical system, such as a WDM-PON, for transmitting optical signals at multiple channel wavelengths. The system generally includes a plurality of laser emitters (e.g., gain chips) optically coupled to and separated from respective exit reflectors (e.g., tunable narrow-band reflectors), thereby forming an array of external cavity lasers with extended lasing cavities. The exit reflectors may be distributed Bragg reflectors (DBRs) located in the waveguides in an arrayed waveguide grating (AWG). The laser emitters emit a range of wavelengths including multiple channel wavelengths and the DBRs reflect a subset of channel wavelengths including at least a channel wavelength associated with the laser emitter such that lasing occurs at the subset of channel wavelengths. The AWG then filters the emitted laser light at the associated channel wavelengths.
    Type: Grant
    Filed: August 27, 2012
    Date of Patent: October 13, 2015
    Assignee: Applied Optoelectronics, Inc.
    Inventor: Wen-Yen Hwang
  • Patent number: 9134538
    Abstract: Coherent beam combining of laser gain elements achieves high output power in a diffraction limited beam. An active beam combining system coherently combines optical beams emitted by semiconductor laser gain elements in an external resonant cavity configuration. A beam combiner in the resonant cavity combines the outputs of the laser gain elements into a single coherent output beam whose power is monitored by a photodetector. A processor uses the photodetector's output to adjust the phases of the respective optical beams emitted by the laser gain elements so as to increase or maximize the coherent output beam's power. The processor may vary the optical beams' phases according to a stochastic parallel gradient descent (SPGD) algorithm for active phase control. Experimental results show a beam combining efficiency of 81% with an upper limit of 90% or higher and without the scaling limits imposed on passive-phasing systems.
    Type: Grant
    Filed: February 6, 2013
    Date of Patent: September 15, 2015
    Assignee: Massachusetts Institute of Technology
    Inventors: Steven J. Augst, Juan Camilo Montoya, Tso Yee Fan, Antonio Sanchez-Rubio
  • Patent number: 9076461
    Abstract: An optical information recording/reproducing apparatus for recording an interference pattern between signal light and reference light information-multiplexed as a hologram in an optical information recording medium and for reproducing information recorded in the optical information recording medium on the basis of the recorded hologram with use of the reference light. The apparatus includes a light source for emitting light and a coherency controller for controlling a coherency of the light source. The apparatus controls the coherency controller in such a manner as to switch between a coherency required in a recording mode and a coherency required in a reproducing mode.
    Type: Grant
    Filed: April 3, 2014
    Date of Patent: July 7, 2015
    Assignee: Hitachi-LG Data Storage, Inc.
    Inventors: Toshiki Ishii, Koichiro Nishimura, Naohito Ikeda, Kazuyoshi Yamazaki
  • Patent number: 9048614
    Abstract: Dry oxygen, dry air, or other gases such as ozone are hermetically sealed within the package of the external cavity laser or ASE swept source to avoid packaging-induced failure or PLF. PIF due to hydrocarbon breakdown at optical interfaces with high power densities is believed to occur at the SLED and/or SOA facets as well as the tunable Fabry-Perot reflector/filter elements and/or output fiber. Because the laser is an external cavity tunable laser and the configuration of the ASE swept sources, the power output can be low while the internal power at surfaces can be high leading to PIF at output powers much lower than the 50 mW.
    Type: Grant
    Filed: January 8, 2014
    Date of Patent: June 2, 2015
    Assignee: Axsun Technologies, Inc.
    Inventors: Peter S. Whitney, Dale C. Flanders
  • Patent number: 9042422
    Abstract: Disclosed is an ASE-free continuously tunable external resonator laser in which reduction in tuning range and decrease in output are suppressed. The external resonator laser comprises: a fixed support body which has a half mirror that partially reflects incident light and partially transmits incident light fixed therein; and a rotatory support body which is rotatably supported by the fixed support body by way of a shaft, and which has a laser chip that emits light, a collimator lens that collimates light emitted from the laser chip, and a diffraction grating that diffracts light emitted from the laser chip, fixed therein.
    Type: Grant
    Filed: December 30, 2010
    Date of Patent: May 26, 2015
    Assignee: NATIONAL UNIVERSITY CORPORATION CHIBA UNIVERSITY
    Inventors: Kiyohumi Muro, Tomohisa Endo, Yasutaka Shimada, Daisuke Fukuoka
  • Patent number: 9042423
    Abstract: Improved brightness and feedback multi-emitter laser diode modules and methods are provided. A plurality of laser diode emitters emit broad-area light beams in a beam direction. In cross-section, each beam is broad in its slow axis and narrow in its fast axis. Groups of downstream optical components collimate, shape, stack and direct the beams along a light path towards a beam spot (which may be fiber-coupled). After collimating, stacking and directing, the beams are Fourier transformed in the fast-axis through a lens feature having a fast-axis focal length less than about 3 millimeters. In some embodiments, the fast-axis focal length is between about 0.1 and 2.0 millimeters. Astigmatism may be introduced between the fast axis and the slow axis in the beams upstream of the lens feature and in accordance with the fast axis focal length of the lens feature. The emitters may receive feedback including wavelength locking feedback.
    Type: Grant
    Filed: June 27, 2013
    Date of Patent: May 26, 2015
    Assignee: JDS Uniphase Corporation
    Inventor: Martin H. Muendel
  • Patent number: 9042414
    Abstract: A tunable laser source that includes multiple gain elements and uses a spatial light modulator in an external cavity to produce spectrally tunable output is claimed. Several designs of the external cavity are described, targeting different performance characteristics and different manufacturing costs for the device. Compared to existing devices, the tunable laser source produces high output power, wide tuning range, fast tuning rate, and high spectral resolution.
    Type: Grant
    Filed: June 7, 2011
    Date of Patent: May 26, 2015
    Assignee: Spectral Sciences, Inc.
    Inventors: Pajo Vukovic-Cvijin, Neil Goldstein
  • Patent number: 9036668
    Abstract: A method for quasi-synchronous tuning of wavelength or frequency of grating external-cavity semiconductor laser and a corresponding semiconductor laser are provided. A grating or mirror is rotated around a quasi-synchronous tuning point (Pq) as rotation center, so as to achieve the frequency selections by grating and resonance cavity in quasi-synchronous tuning, wherein the angle of the line between the quasi-synchronous tuning point (Pq) and a conventional synchronous tuning point (P0) with respect to the direction of light incident on the grating is determined according to the angle difference between the incidence angle and diffraction angle of light on the grating. According to present invention, approximately synchronous tuning of laser is achieved with a simple and flexible design.
    Type: Grant
    Filed: June 10, 2009
    Date of Patent: May 19, 2015
    Assignee: NATIONAL INSTITUTE OF METROLOGY P.R. CHINA
    Inventors: Erjun Zang, Jianping Cao, Ye Li, Zhanjun Fang
  • Patent number: 9031112
    Abstract: A manufacturing method for an excimer laser that includes a reflective Echelle diffraction grating includes obtaining information of a wavelength of a light source, a blazed order, a repetitive pitch of the grating, a material of the grating, and a predefined orientation ratio B/A that is a ratio between that a diffraction efficiency A of the blazed order and a diffraction efficiency Bb of an order lower by one order than the blazed order, and determining an initial value of a blaze angle based upon these pieces of information.
    Type: Grant
    Filed: October 2, 2012
    Date of Patent: May 12, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tsuyoshi Kitamura, Takashi Sukegawa
  • Patent number: 9031113
    Abstract: The invention relates to an optical resonator, laser apparatus and a method of generating a laser beam inside an optical resonator. The optical resonator (100) includes an optical cavity (102) and an optical element (104.1, 104.2) at either end thereof, operable to sustain a light beam (108) therein, characterized in that each optical element (104.1, 104.2) is a phase-only optical element operable to alter a mode of the beam (108) as it propagates along the length of the optical resonator (100), such that in use the beam (108) at one end of the optical resonator (100) has a Gaussian profile while the beam (108) at the other end of the optical resonator (100) has a non-Gaussian profile.
    Type: Grant
    Filed: April 29, 2010
    Date of Patent: May 12, 2015
    Assignee: CSIR
    Inventors: Ihar Anatolievich Litvin, Andrew Forbes
  • Patent number: 9014223
    Abstract: Systems and methods of optical parametric chirped pulse amplification for laser pulses are provided. Techniques and components include replacing pulse stretcher and/or pulse compressors with chirped volume Bragg gratings (CVBGs) to reduce size, weight, cost, and environmental sensitivity of the laser system.
    Type: Grant
    Filed: December 28, 2011
    Date of Patent: April 21, 2015
    Assignee: Lockheed Martin Corporation
    Inventor: Edward J. Miesak
  • Patent number: 8995477
    Abstract: An ultrashort pulse laser processing apparatus for processing a processing target includes: a laser head which includes a seed laser source emitting an ultrashort pulse seed laser, and emits a laser pulse; an optical fiber which guides the laser pulse emitted from the laser head; and an emission end unit which includes a compressor that compresses the laser pulse emitted from the optical fiber to a laser pulse of a predetermined high peak power and emits the laser pulse compressed by the compressor to the target.
    Type: Grant
    Filed: March 2, 2012
    Date of Patent: March 31, 2015
    Assignee: Nidek Co., Ltd.
    Inventor: Masanori Amano
  • Patent number: 8995482
    Abstract: A high energy semiconductor laser capable of high optical efficiency includes a master oscillator coupled to a plurality of slave oscillators, each producing a laser beam that is substantially at the same wavelength as the output beam from the master oscillator. The outputs of the slave oscillators are then coherently combined to a single monochromatic beam having an optical power which is substantially greater than that of beam output from the master oscillator. The slave oscillators can be configured as ring resonators. A suitable ring oscillator can be built by arranging one or more semiconductor diode laser gain media, two or more reflecting mirrors, and at least one semireflective mirror in a ring configuration. A suitable ring oscillator can also be built by machining a solid block to include one or more semiconductor diode laser high gain regions.
    Type: Grant
    Filed: November 3, 2010
    Date of Patent: March 31, 2015
    Inventors: Peter Moshchansky-Livingston, Richard A. Hutchin
  • Patent number: 8995495
    Abstract: A tunable DBR laser including: an amplifier section, a part-reflecting optical output, a connection section connected to the amplifier section, and at least two wavelength-selective reflectors optically coupled to the amplifier section via the connection section. The connection section includes at least one MMI coupler and several waveguides, so that different optical paths lead from the amplifier section to the wavelength-selective reflectors and each of the different optical paths leads through the at least one MMI coupler and through one of the waveguides. The wavelength-selective reflectors differ from one another by having different reflection spectra and each of the wavelength-selective reflectors is connected to one of several outputs of the at least one MMI coupler. By activating a phase shifter, arranged in a course of at least one of the waveguides, the DBR laser can be switched between different resonators.
    Type: Grant
    Filed: December 10, 2012
    Date of Patent: March 31, 2015
    Assignee: Fraunhofer-Gesellschaft zur Foerderung der Angewandten Forschung e.V.
    Inventors: Martin Schell, Patrick Runge
  • Patent number: 8976820
    Abstract: To provide a passive Q-switch-type solid laser apparatus for outputting a high peak-power pulse laser whose pulse energy is large and pulse-time width is small. A passive Q-switch-type solid laser apparatus has: two reflection elements for forming an oscillator; a solid gain medium being disposed between the two reflection elements; a saturable absorber being disposed between the two reflection elements; an excitation device for exciting the solid gain medium; and a cross section control device for making at least one of a stimulated emission cross section of the solid gain medium and an absorption cross section of the saturable absorber closer to another one of them; and the cross section control device is equipped with at least one or both of a temperature control device for retaining the solid gain medium at a predetermined temperature and an oscillatory-wavelength control device for fixating an oscillatory wavelength at a predetermined wavelength.
    Type: Grant
    Filed: May 21, 2012
    Date of Patent: March 10, 2015
    Assignee: Inter-University Research Institute Corporation National Institutes of Natural Sciences
    Inventors: Takunori Taira, Simon Joly, Rakesh Bhandari
  • Patent number: 8971360
    Abstract: An optical module includes a light source. The light source can be a swept wavelength light source, and optical module includes a wavemeter. The wavemeter includes a wavemeter tap capable of directing a wavemeter portion of light produced by the light source away from a main beam, a wavelength selective filter arranged to receive the wavemeter portion, a first wavemeter detector arranged to measure a transmitted radiation intensity of radiation transmitted through the filter, and a second wavemeter detector arranged to measure a non-transmitted radiation intensity of radiation not transmitted through but reflected by the filter. In addition, an optical coherence tomography apparatus includes the optical module.
    Type: Grant
    Filed: December 6, 2013
    Date of Patent: March 3, 2015
    Assignee: Exalos AG
    Inventors: Jan Lewandowski, Marcus Duelk, Christian Velez
  • Patent number: 8964798
    Abstract: A laser system for semiconductor inspection includes a fiber-based fundamental light source for generating fundamental light that is then converted/mixed by a frequency conversion module to generate UV-DUV laser light. The fundamental light source includes a nonlinear chirp element (e.g., a Bragg grating or an electro-optic modulator) that adds a nonlinear chirp to the seed light laser system prior to amplification by the fiber amplifier(s) (e.g., doped fiber or Raman amplifiers). The nonlinear chirp includes an x2 or higher nonlinearity and is configured to compensate for the Self Phase Modulation (SPM) characteristics of the fiber-based amplifiers such that fundamental light is generated that has a spectral E95 bandwidth within five times that of the seed light. When multiple series-connected amplifiers are used, either a single nonlinear chirp element is provided before the amplifier string, or chirp elements are included before each amplifier.
    Type: Grant
    Filed: July 10, 2013
    Date of Patent: February 24, 2015
    Assignee: KLA-Tencor Corporation
    Inventor: J. Joseph Armstrong
  • Patent number: 8953649
    Abstract: A method for quasi-synchronous tuning of wavelength or frequency of grating external-cavity semiconductor laser and a corresponding semiconductor laser are provided. A grating or mirror is rotated around a quasi-synchronous tuning point (Pq) as rotation center, so as to achieve the frequency selections by grating and resonance cavity in quasi-synchronous tuning, wherein the angle of the line between the quasi-synchronous tuning point (Pq) and a conventional synchronous tuning point (P0) with respect to the direction of light incident on the grating is determined according to the angle difference between the incidence angle and diffraction angle of light on the grating. According to present invention, approximately synchronous tuning of laser is achieved with a simple and flexible design.
    Type: Grant
    Filed: January 15, 2014
    Date of Patent: February 10, 2015
    Assignee: National Institute of Metrology P.R. China
    Inventors: Erjun Zang, Jianping Cao, Ye Li, Zhanjun Fang
  • Patent number: 8948228
    Abstract: In one embodiment, the invention relates to systems, methods and devices for improving the operation of an electromagnetic radiation source or component thereof. In one embodiment, the source is a laser source. A Fourier domain mode locked laser can be used in various embodiments. The sources described herein can be used in an optical coherence tomography (OCT) system such as a frequency domain OCT system. In one embodiment, laser coherence length is increased by compensating for dispersion. A frequency shifter can also be used in one embodiment to compensate for a tunable filter induced Doppler shift.
    Type: Grant
    Filed: October 8, 2013
    Date of Patent: February 3, 2015
    Assignee: LightLab Imaging, Inc.
    Inventor: Desmond Adler
  • Patent number: 8923358
    Abstract: A two-dimensional photonic crystal surface emitting laser light source includes a two-dimensional photonic crystal made of a plate-shaped body material provided with a periodic arrangement of identically-shaped holes and an active layer. The hole is not located on a first half-line extending from the gravity center of the hole, while the hole is located on a second half-line extending in the direction opposite to the first half-line. Injecting electric charges into the active layer generates light, which creates an electric field encircling the gravity center. For a given point on the second half-line where the hole is located, there is no hole at a point that is symmetrical to the aforementioned point with respect to the gravity center, so that the electric field vectors at the two points do not cancel each other and the laser light is stronger than conventional examples.
    Type: Grant
    Filed: March 30, 2007
    Date of Patent: December 30, 2014
    Assignees: Kyoto University, Rohm Co., Ltd.
    Inventors: Susumu Noda, Yoshitaka Kurosaka, Eiji Miyai, Dai Ohnishi, Wataru Kunishi
  • Publication number: 20140362886
    Abstract: An external resonator type light emitting system includes a light source oscillating a semiconductor laser light and a grating device providing an external resonator with the light source. The light source includes an active layer oscillating the semiconductor laser light. The grating device includes an optical waveguide having an incident face to which the semiconductor laser is incident and an emitting face of emitting an emitting light of a desired wavelength, a Bragg grating formed in the optical waveguide, and a propagating portion provided between the incident face and the Bragg grating. Formulas (1) to (4) are satisfied.
    Type: Application
    Filed: April 22, 2014
    Publication date: December 11, 2014
    Applicant: NGK INSULATORS, LTD.
    Inventors: Jungo Kondo, Shoichiro Yamaguchi, Takashi Yoshino, Yukihisa Takeuchi
  • Patent number: 8902937
    Abstract: The present disclosure relates to a compact external cavity tunable laser apparatus. The laser apparatus includes a substrate, an external cavity tunable reflecting unit that reflects laser light entering from the outside on the substrate and selects and varies a wavelength of the reflected laser light, an optical fiber that outputs the laser light on the substrate; and an highly integrated light source that integrates the laser light input from the external cavity tunable reflecting unit using inclined input and output waveguides, a curved waveguide, and a straight waveguide to output the integrated laser light to the optical fiber in order to match an optical axis formed with the external cavity tunable reflecting unit with an optical axis formed with an optical fiber.
    Type: Grant
    Filed: March 21, 2013
    Date of Patent: December 2, 2014
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Ki-Hong Yoon, O-Kyun Kwon, Kisoo Kim, Byungseok Choi, Hyun Soo Kim, Su Hwan Oh
  • Publication number: 20140348200
    Abstract: Volumetric Bragg grating devices that operate in middle-infrared region of the spectrum and methods for producing such devices are described. Such a Volumetric Bragg grating device can be produced by forming a plurality of color centers within an alkali-halide crystal and selectively removing a subset of the plurality of color centers to produce variations in refractive index of the alkali-halide crystal in the middle-infrared spectral region and to thereby produce a volumetric Bragg grating that operates in middle-infrared spectral range.
    Type: Application
    Filed: January 14, 2013
    Publication date: November 27, 2014
    Inventors: Anitha Arumugam, Dmitry V. Martyshkin, Vladimir V. Fedorov, David J. Hilton, Sergey B. Mirov
  • Patent number: 8891575
    Abstract: An optical resonator can include an optical feedback structure disposed on a substrate, and a composite including a matrix including a chromophore. The composite disposed on the substrate and in optical communication with the optical feedback structure. The chromophore can be a semiconductor nanocrystal. The resonator can provide laser emission when excited.
    Type: Grant
    Filed: November 29, 2005
    Date of Patent: November 18, 2014
    Assignee: Massachusetts Institute of Technology
    Inventors: Preston T. Snee, Yin Thai Chan, Daniel G. Nocera, Moungi G. Bawendi
  • Publication number: 20140321494
    Abstract: Volumetric Bragg grating devices that operate in middle-infrared region of the spectrum and methods for producing such devices are described. Such a Volumetric Bragg grating device can be produced by forming a plurality of color centers within an alkali-halide or an alkali-earth fluoride crystal and selectively removing a subset of the plurality of color centers to produce variations in refractive index of the alkali-halide or alkali-earth fluoride crystal in the middle-infrared spectral region and to thereby produce a volumetric Bragg grating that operates in middle-infrared spectral range.
    Type: Application
    Filed: July 14, 2014
    Publication date: October 30, 2014
    Inventors: Anitha Arumugam, Dmitry V. Martyshkin, Vladimir V. Fedorov, David J. Hilton, Sergey B. Mirov
  • Publication number: 20140321495
    Abstract: An integrated sub-wavelength grating element includes a transparent layer formed over an optoelectronic substrate layer and a sub-wavelength grating element formed into a grating layer disposed on said transparent layer. The sub-wavelength grating element is formed in alignment with an active region of an optoelectronic component within the optoelectronic substrate layer. The sub-wavelength grating element affects light passing between said grating element and said active region. A method for forming an integrated sub-wavelength grating element is also provided.
    Type: Application
    Filed: January 18, 2012
    Publication date: October 30, 2014
    Applicant: HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P.
    Inventors: David A. Fattal, Raymond G. Beausoleil, Marco Fiorentino, Paul Kessler Rosenberg, Terrel Morris
  • Patent number: 8867577
    Abstract: A laser light source according to the present invention includes a laser element that outputs a fundamental wave; a wavelength conversion element into which the fundamental wave is input and that converts at least a part of the fundamental wave input therein to a converted wave having a wavelength shorter than the wavelength of the fundamental wave; a waveguide that attenuates a component of the fundamental wave included in an output wave from the wavelength conversion element; and a diffraction grating that is formed on the waveguide and feeds back the fundamental wave output from the wavelength conversion element to lock the wavelength or the frequency of the fundamental wave output from the laser element. The diffraction grating is formed at a position determined taking into account an amount by which the fundamental wave is attenuated in the waveguide.
    Type: Grant
    Filed: December 20, 2012
    Date of Patent: October 21, 2014
    Assignee: Citizen Holdings Co., Ltd.
    Inventors: Shinpei Fukaya, Masafumi Ide
  • Patent number: 8867586
    Abstract: A diode laser is provided with wavelength stabilization and vertical collimation of the emitted radiation, which allows a small distance of the volume Bragg grating from the emitting surface, a small vertical diameter of the collimated beam and also compensation for manufacturing tolerances affecting the shape of the grating and the lens. The diode laser comprises an external frequency-selective element for wavelength stabilization of the laser radiation, wherein the external frequency-selective element comprises an entry surface facing the exit facet and an exit surface facing away from the exit facet and is designed as a volume Bragg grating; and wherein the external frequency-selective element is designed in such a manner that the divergence of the radiation emitting from the exit facet is reduced during passage through the external frequency-selective element.
    Type: Grant
    Filed: March 27, 2012
    Date of Patent: October 21, 2014
    Assignee: Forschungsverbund Berlin E.V.
    Inventor: Bernd Eppich
  • Patent number: 8867578
    Abstract: A cable television transmitter includes a substrate including a silicon material, control electronics disposed in the substrate, and a gain medium coupled to the substrate. The gain medium includes a compound semiconductor material. The cable television transmitter also includes an optical modulator optically coupled to the gain medium and electrically coupled to the control electronics, a waveguide disposed in the substrate and optically coupled to the gain medium, a first wavelength selective element characterized by a first reflectance spectrum and disposed in the substrate, and a second wavelength selective element characterized by a second reflectance spectrum and disposed in the substrate. The cable television transmitter further includes an optical coupler disposed in the substrate and joining the first wavelength selective element, the second wavelength selective element, and the waveguide and an output mirror.
    Type: Grant
    Filed: March 3, 2011
    Date of Patent: October 21, 2014
    Assignee: Skorpios Technologies, Inc.
    Inventors: John Dallesasse, Stephen B. Krasulick, William Kozlovsky
  • Patent number: 8861556
    Abstract: A spatially modulated waveguide Bragg grating mirror is suspended over a substrate by plurality of fingers extending laterally away from the waveguide centerline. The positions of the fingers are coordinated with the positions of crests and valleys of amplitude or phase modulation of the Bragg grating, to avoid disturbing the Bragg grating when it is tuned by heating. When the Bragg grating is heated, the heat flows through the fingers creating a quasi-periodic refractive index variation along the Bragg grating due to quasi-periodic temperature variation created by the heat flow from the grating through the supporting fingers. Due to coordination of the positions of supporting fingers with positions of the crests and valleys of modulation, the optical phase coherence is maintained along the Bragg grating, so that the spectral lineshape or filtering property of the Bragg grating is substantially preserved.
    Type: Grant
    Filed: July 5, 2012
    Date of Patent: October 14, 2014
    Assignee: JDS Uniphase Corporation
    Inventor: Michael C. Larson
  • Patent number: 8842710
    Abstract: There are provided a process for producing a semiconductor device and a semiconductor device which allow conductivity distribution to be formed without making refractive index distributed even in a material system of a semiconductor difficult to be subjected to ion implantation. The process for producing a semiconductor device includes the steps of forming a semiconductor layer containing a dopant; forming a concave and convex structure on the semiconductor layer by partially removing the semiconductor layer; and forming a conductivity distribution reflecting the concave and convex structure in the semiconductor layer by performing heat treatment on the semiconductor layer in which the concave and convex structure has been formed at a temperature at which a material forming the semiconductor layer causes mass transport and filling up a hole of a concave portion of the concave and convex structure with the material forming the semiconductor layer.
    Type: Grant
    Filed: July 27, 2010
    Date of Patent: September 23, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yasuhiro Nagatomo, Takeshi Kawashima, Katsuyuki Hoshino, Shoichi Kawashima
  • Publication number: 20140269808
    Abstract: A laser assembly (10) that generates a beam (12) includes (i) a gain medium (22) that generates the beam (12) when electrical power is directed to the gain medium (22); (ii) a grating (32) positioned in a path of the beam (12); (iii) a grating arm (34) that retains the grating (32); and (iv) a mover assembly (36) that moves the grating arm (34) about a pivot axis (38). The mover assembly (36) includes a coarse mover (344) that makes large scale movements to the grating arm (34), and a fine mover (352) that makes fine movements to the grating arm (34). With this design, the mover assembly (36) can quickly and accurately move the grating (32) over a relatively large range.
    Type: Application
    Filed: March 15, 2013
    Publication date: September 18, 2014
    Inventors: Michael Pushkarsky, Martin Algots, Satino Marrone, John Craig, Alexander Dromaretsky
  • Patent number: 8831051
    Abstract: Techniques, devices and systems for optical communications based on wavelength division multiplexing (WDM) that use tunable multi-wavelength laser transmitter modules.
    Type: Grant
    Filed: May 3, 2013
    Date of Patent: September 9, 2014
    Assignee: Google Inc.
    Inventors: Hong Liu, Cedric F. Lam
  • Patent number: 8817832
    Abstract: A multi-wavelength laser array of a plurality of emitters in a diode bar or stack where each beam is deflected by a different angle to be incident upon a uniform volume holographic grating with a portion of the beam being deflected as a feedback portion while a further portion provides a wavelength tuned output unique to each emitter. The arrangement of a uniform volume holographic grating with deflectors such as phaseplates eliminates the need to use expensive wavelength chirped gratings.
    Type: Grant
    Filed: May 7, 2012
    Date of Patent: August 26, 2014
    Assignee: Power Photonic Ltd.
    Inventors: Natalia Trela, Howard John Baker, Roy McBride
  • Patent number: 8804778
    Abstract: An extreme ultraviolet light source apparatus comprises a laser apparatus having a master oscillator outputting one or more longitudinal-mode-laser lights, an amplifier with a molecular gas as an amplifying agency amplifying a longitudinal-mode laser light of which wavelength is included in one of amplifiable lines, and a controller adjusting the master oscillator so that the wavelength of the longitudinal-mode laser light outputted from the master oscillator is included in one of the amplifiable lines, the laser apparatus being used as a driver laser, wherein the laser apparatus irradiates a target material with a laser light for generating plasma, and the extreme ultraviolet light is emitted from the plasma and outputted from the extreme ultraviolet light source apparatus.
    Type: Grant
    Filed: October 16, 2009
    Date of Patent: August 12, 2014
    Assignee: Gigaphoton Inc.
    Inventors: Osamu Wakabayashi, Akira Endo, Krzysztof Nowak, Takashi Suganuma, Masato Moriya
  • Patent number: 8792528
    Abstract: Disclosed are semiconductor microtube lasers including a semiconductor multilayer heterostructure. The multilayer heterostructure includes a substantially cylindrical optically active structure capable of light emission when under the influence of an applied electromagnetic field and a substantially cylindrical distributed feedback grating structure configured to provide optical feedback for a selected wavelength of light from the optically active region and to produce lasing action from the microtube when under the influence of an applied electromagnetic field.
    Type: Grant
    Filed: May 9, 2012
    Date of Patent: July 29, 2014
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Robert H. Blick, Luke J. Mawst
  • Patent number: 8774247
    Abstract: An Echelle diffraction grating has a Littrow configuration. Each grating includes a resin layer made of light curing resin and having a thickness between 2 ?m and 10 ?m, and a reflective coating layer formed on the resin layer, having a thickness between 120 nm and 500 nm, and made of aluminum. An apex angle between a blazed surface and a counter surface is between 85° and 90°. A first blaze angle is an angle that maximizes diffraction efficiency of a set blazed order for incident light of a wavelength of 193.3 nm. A blaze angle has an initial value of a second blaze angle smaller than the first blaze angle. 0.25°?bd?ba?1.2° is satisfied where bd denotes the first blaze angle and ba denotes the second blaze angle.
    Type: Grant
    Filed: October 2, 2012
    Date of Patent: July 8, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takashi Sukegawa, Tsuyoshi Kitamura, Yukinobu Okura
  • Patent number: 8774240
    Abstract: A frequency-drift amplification device for a pulsed laser, including: a stretcher for time-stretching an incident laser pulse; at least one amplifying medium for amplifying the laser pulse; a main compressor for time-compressing the laser pulse to a desired duration for an output pulse of the amplification device; and at least one adjustment compressor between the stretcher and the main compressor, and in which the laser pulse undergoes four diffractions on diffraction gratings to time-compress the stretched laser pulse to a duration that is greater than the desired duration for the output pulse of the amplification device.
    Type: Grant
    Filed: September 30, 2011
    Date of Patent: July 8, 2014
    Assignee: Ecole Polytechnique
    Inventor: Gilles Cheriaux
  • Patent number: 8767789
    Abstract: A method of fabrication of laser gain material and utilization of such media includes the steps of introducing a transitional metal, preferably Cr2+ thin film of controllable thickness on the ZnS crystal facets after crystal growth by means of pulse laser deposition or plasma sputtering, thermal annealing of the crystals for effective thermal diffusion of the dopant into the crystal volume with a temperature and exposition time providing the highest concentration of the dopant in the volume without degrading laser performance due to scattering and concentration quenching, and formation of a microchip laser either by means of direct deposition of mirrors on flat and parallel polished facets of a thin Cr:ZnS wafer or by relying on the internal reflectance of such facets. Multiple applications of the laser material are contemplated in the invention.
    Type: Grant
    Filed: December 1, 2011
    Date of Patent: July 1, 2014
    Assignee: The UAB Research Foundation
    Inventors: Sergey B. Mirov, Vladimir V. Fedorov
  • Patent number: 8755421
    Abstract: High-power, phased-locked, laser arrays as disclosed herein utilize a system of optical elements that may be external to the laser oscillator array. Such an external optical system may achieve mutually coherent operation of all the emitters in a laser array, and coherent combination of the output of all the lasers in the array into a single beam. Such an “external gain harness” system may include: an optical lens/mirror system that mixes the output of all the emitters in the array; a holographic optical element that combines the output of all the lasers in the array, and an output coupler that selects a single path for the combined output and also selects a common operating frequency for all the coupled gain regions.
    Type: Grant
    Filed: November 21, 2012
    Date of Patent: June 17, 2014
    Assignee: PD-LD, Inc.
    Inventor: Boris Leonidovich Volodin
  • Patent number: 8755415
    Abstract: An optical fiber laser or amplifier comprising an optical fiber and a pump radiation source configured to generate pump radiation which is received through an input end of the optical fiber. The optical fiber may include a doped core which is configured to guide the pump radiation and to generate or amplify and guide signal radiation when pump radiation passes through it. The optical fiber laser or amplifier may include a first reflector configured to reflect pump radiation and further comprises a second reflector configured to selectively reflect a portion of pump radiation. The selection of the portion of pump radiation to be reflected by the second reflector depends upon one or more of: the spatial position of the pump radiation, the direction of the pump radiation, and the polarization of the pump radiation.
    Type: Grant
    Filed: June 14, 2012
    Date of Patent: June 17, 2014
    Assignee: Laser Quantum Inc.
    Inventor: Alan Cox
  • Patent number: 8737447
    Abstract: A nitride semiconductor surface-emitting laser includes a two-dimensional photonic crystal layer having a resonant mode in an in-plane direction. The surface-emitting laser includes an active layer, the two-dimensional photonic crystal layer, a semiconductor layer, and an electrode in this order. The two-dimensional photonic crystal layer contains p-type conductive InxGa1-xN (0?x?1) as a high-refractive-index medium. The semiconductor layer contains p-type conductive InyGa1-yN (0?y?1). The thickness tPhC of the two-dimensional photonic crystal layer satisfies the relation of tPhC?(?/neff), wherein ? denotes the lasing wavelength, and neff denotes the effective refractive index of the resonant mode.
    Type: Grant
    Filed: March 25, 2010
    Date of Patent: May 27, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shoichi Kawashima, Yasuhiro Nagatomo
  • Patent number: 8711367
    Abstract: A position-measuring device, for ascertaining the position of two objects which are disposed in a manner allowing movement relative to each other in at least one measuring direction, includes a light source, as well as a splitting device by which a light beam, provided by the light source, is split into two or more partial beams of rays. The partial beams of rays traverse at least two partial-beam paths. Interfering partial beams of rays from the partial-beam paths strike a plurality of opto-electronic detector elements, so that displacement-dependent position signals are ascertainable via the detector elements. The light source takes the form of a semiconductor laser having a fiber-grating feedback device.
    Type: Grant
    Filed: December 7, 2010
    Date of Patent: April 29, 2014
    Assignee: Dr. Johannes Heidenhain GmbH
    Inventor: Markus Meissner
  • Patent number: 8693894
    Abstract: A gain clamped optical device includes a semiconductor stack and a resonant cavity configured to emit stimulated light. A window created in the optical device is configured to emit the stimulated light in an LED mode.
    Type: Grant
    Filed: October 28, 2008
    Date of Patent: April 8, 2014
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Shih-Yuan Wang, Michael Tan, Alexandre Bratkovski, Sagi Mathai
  • Patent number: 8693517
    Abstract: A semiconductor laser using an external resonator. A laser diode chip emits a laser beam in a horizontal direction parallel to the bottom plane of a package, and the travel path of the laser beam is changed into a vertical direction by a reflective mirror next to a laser beam-emitting surface of the laser diode chip. As a result, the beam arrangement of the external cavity is available on a plane parallel to the bottom plane of the package through a lens installed on the vertical travel path of the laser beam. Consequently, the beam is easily arranged. Furthermore, an additional reflective mirror is installed above the lens which changes the vertical travel path into a horizontal travel path, which allows the beam traveling parallel to the bottom plane to be easily arranged through the lens. The production of the package can also be enabled in the configuration where various optical tools are arranged on the bottom of the package.
    Type: Grant
    Filed: August 24, 2009
    Date of Patent: April 8, 2014
    Inventor: Jeong Soo Kim
  • Patent number: 8687667
    Abstract: To improve a laser system comprising at least one externally stabilizable semiconductor laser, from the laser active zone of which a laser radiation field can be coupled out, and a feedback element, disposed externally in the laser radiation field, which couples out, from the laser radiation field, a feedback radiation field having a defined wavelength and bandwidth, and couples back same into the active laser zone for determining the wavelength and bandwidth of the laser radiation field, in such a way that the wavelength stabilization may be achieved more cost-effectively, it is proposed that the feedback element is a resonant waveguide grating which reflects back a portion of the laser radiation field lying within an angular acceptance range.
    Type: Grant
    Filed: September 21, 2012
    Date of Patent: April 1, 2014
    Assignee: Universitaet Stuttgart Institut fuer Strahlwerkzeuge
    Inventors: Marwan Abdou Ahmen, Andreas Voss
  • Patent number: RE45249
    Abstract: The bandwidth selection mechanism includes a first actuator mounted on a second face of a dispersive optical element, the second face being opposite from a reflective face, the first actuator having a first end coupled to a first end block and a second end coupled to a second end block, the first actuator being operative to apply equal and opposite forces to the first end block and the second end block to bend the body of the dispersive optical element along the longitudinal axis of the body and in a first direction normal to the reflective face of the dispersive optical element. The bandwidth selection mechanism also includes a second actuator being operative to apply equal and opposite forces to bend the body along the longitudinal axis of the body, in a second direction perpendicular to the reflective face of the dispersive optical element.
    Type: Grant
    Filed: February 26, 2013
    Date of Patent: November 18, 2014
    Assignee: Cymer, LLC
    Inventors: Efrain Figueroa, William N. Partlo, John Martin Algots