Particular Pumping Means Patents (Class 372/69)
  • Patent number: 6944202
    Abstract: An energy converter reacts hydrocarbons and air on a catalyst configuration to produce a population inversion. A photovoltaic system may extract the radiating energy, and a laser system may extract a significant fraction of the reaction energy in the form of coherent radiation. The flooding of the catalyst adsorption sites with fuel and the choice of catalyst predisposes the adsorbing oxygen molecules to create mono-atomic oxygen hot-atoms, which deposit the considerable energy of oxygen adsorption directly into a reaction channel of adjacent, adsorbed and simple fuel radicals, thereby producing simple, energetic product molecules, concentrating the energy in one or a few modes, and strongly favoring inverted populations. A solid state method to stimulate precursor chemisorbed specie dissociation accelerates the reaction rates, providing a method to greatly intensify pulsed power output, increase efficiency, and to facilitate nano-scale and micro-scale thermal energy heat rejection processes.
    Type: Grant
    Filed: August 14, 2002
    Date of Patent: September 13, 2005
    Assignee: Neokismet, L.L.C.
    Inventors: Anthony C. Zuppero, Jawahar M. Gidwani
  • Patent number: 6937630
    Abstract: To provide a laser oscillation method and a laser device, which use a laser medium such as an Nd:GdVO4 crystal to which neodymium is doped in high concentration exceeding 1% in atomicity ratio, the laser medium comprised of the gadolinium-vanadate crystal to which neodymium as laser active ion is doped by a floating zone method such that concentration becomes exceeding 1% in atomicity ratio.
    Type: Grant
    Filed: September 10, 2002
    Date of Patent: August 30, 2005
    Assignees: Riken, NEC Tokin Corporation, Megaopto Co., Ltd.
    Inventors: Satoshi Wada, Takayo Ogawa, Hideo Tashiro, Hiroshi Machida, Mikio Higuchi, Kohei Kodaira, Tomohiro Shonai
  • Patent number: 6931047
    Abstract: In the first period from pumping start time T1 to time T2 in a laser light source 1, the power of pumping light L1 outputted from a pumping light source 41 so as to irradiate a laser medium 21 is at value P1 whereas the power of light L2 incident on a saturable absorber 30 after being emitted from the laser medium 21 is at an absorption saturation threshold or lower, which causes a resonator 10 to lower its Q-value, thereby suppressing the laser oscillation. Immediately before time T2, the power of light L2 is slightly lower than the absorption saturation threshold. In the second period subsequent to the first period, the power of light L2 is at value P2 greater than the above-mentioned value P1, whereas the power of light L2 exceeds the absorption saturation threshold, which causes the resonator 10 to increase its Q-value, whereby a mirror 12 outputs pulse laser light L3 to the outside.
    Type: Grant
    Filed: December 24, 2002
    Date of Patent: August 16, 2005
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Hirofumi Kan, Akihiro Sone, Hiroshi Sakai, Takunori Taira, Nicolaie Pavel, Voicu Lupei
  • Patent number: 6931037
    Abstract: A diode pumped, multi axial mode, intracavity doubled, intracavity tripled laser, includes at least two resonator mirrors defining a resonator cavity. A laser crystal and a doubling crystal are positioned in the resonator cavity. A tripling crystal is also positioned in the resonator cavity. A diode pump source supplies a pump beam to the laser crystal and produces a laser crystal beam with a plurality of axial modes that are incident on the doubling crystal. This produces a frequency doubled output beam. Further, a diode pumped, multi axial mode, intracavity nonlinearly-converted laser is provided and includes at least two resonator mirrors defining a resonator cavity, a laser crystal and a nonlinear conversion apparatus positioned in the resonator cavity. A nonlinear conversion apparatus is also positioned in the resonator cavity.
    Type: Grant
    Filed: June 1, 2001
    Date of Patent: August 16, 2005
    Assignee: Spectra Physics Lasers, Inc.
    Inventors: William L. Nighan, Jr., John Cole
  • Patent number: 6931034
    Abstract: An optical system has a transmission filter device, a feedback mechanism, and one or more radiation sources. Each radiation source generates an output signal with a predetermined wavelength band and polarization and is coupled to a separate input port of the transmission filter device. The transmission filter device, which is responsive to output signal from each radiation source, generates an output signal from at least one output port thereof. The feedback mechanism is coupled to at least one output port of the transmission filter device for providing a feedback signal that is directed back through the transmission filter device to each of the radiation sources for stabilizing each of the radiation sources. The apparatus is polarization maintaining wherein the one or more radiation sources, the transmission filter device, and the feedback mechanism are interconnected such that principle axes of polarization thereof are substantially aligned.
    Type: Grant
    Filed: August 15, 2003
    Date of Patent: August 16, 2005
    Assignee: Optovia Corporation
    Inventors: Hamid R. Khazaei, Harmeet Singh, Emily M. Squires, David Kirk Lewis
  • Patent number: 6931033
    Abstract: This invention relates to the field of lasers and in particular to the pump sources used in lasers. Many existing lasers use linear flashlamps in order to create population inversion in the gain medium of the laser. Such pump sources suffer from a number of drawbacks particularly when pumping dye lasers including explosive damage, long optical pulse length and inappropriate spectral emission. This invention provides a pump source for a laser which exploits the surface discharge phenomenon. A dielectric material (1) which is in contract with a gas (9) has electrical energy discharged across its surface in order to provide an electromagnetic emission which is then used to pump the gain medium. By varying the dielectric material or the cover gas used (amongst other variables) the surface emission can be used to pump the laser gain medium.
    Type: Grant
    Filed: August 21, 2001
    Date of Patent: August 16, 2005
    Assignee: Qinetiq Limited
    Inventors: David James Fulker, Mark Ralph Venner, Andrew James Finlayson, Anthony David Case
  • Patent number: 6912238
    Abstract: A laser and method of producing laser light. The laser and method involve passing a high energy beam of particles through an evacuated chamber. A static electric or magnetic field is established in the chamber in a direction that is essentially perpendicular to the direction of propagation of the beam, but which is a periodically varying field in the direction of propagation. The velocity of the particles and the variation in the field is sufficient to pump the particles into a higher energy state and produce laser light at the output of the chamber.
    Type: Grant
    Filed: April 10, 2003
    Date of Patent: June 28, 2005
    Inventor: Robert James Howard
  • Patent number: 6904074
    Abstract: A diode-pumped microlaser in accordance with the present invention includes a diode pump, a first lens, a second lens and a laser glass. The diode pump generates an input pump beam. The first lens and second lens manipulate the pump beam by collimating the pump beam in focal planes that are perpendicular to each other. The laser glass receives the manipulated pump beam from the second lens and converts the pump beam into a laser beam. The laser glass is further doped with predetermined amounts by weight of Erbium and Ytterbium to ensure that an output laser beam with an eyesafe wavelength is generated. The microlaser further includes a passive Q-switch made of a Cobalt-spinel material, which receives the output laser beam and generates laser pulses using passive switching techniques, independent of any external temperature control. This configuration allows the microlaser to function as a laser rangefinder over extended temperature ranges in a manner that is eyesafe to the user.
    Type: Grant
    Filed: March 18, 2003
    Date of Patent: June 7, 2005
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: C. Ward Trussell, Jr., Vernon King
  • Patent number: 6898222
    Abstract: A diode laser arrangement is disclosed wherein a radiation source is designed which can be scaled with respect to power such that different types of cooling can be applied and the configuration of the radiation field is suitable for adapting to different tasks in a simple manner. For this purpose, every diode laser is connected to a thermal contact surface of a separate, heat-spreading carrier which is fastened to a cooling surface of a common cooling element so as to be electrically insulated. The carriers are arranged adjacently in such a way that the line-shaped emission regions of the diode lasers are adjacent in series and the p-n junction planes extend parallel to the thermal contact surfaces. The diode laser arrangement is particularly suitable as a pump light source.
    Type: Grant
    Filed: November 21, 2001
    Date of Patent: May 24, 2005
    Assignee: Jenoptik Laserdiode GmbH
    Inventors: Petra Hennig, Guenter Hollemann
  • Patent number: 6891874
    Abstract: The invention relates to a laser amplifier system consisting of a solid body, which comprises a laser-active medium, of a pumping radiation source for generating a pumping radiation field, which repeatedly permeates the solid body, and of a focusing system. Said focusing system generates a number of different branches of the pumping radiation field that enter the solid body and converts at least one branch emerging from the solid body into one of the branches which enter the solid body and which are different from the emerging branch. The aim of the invention is to improve a laser amplifier system of the aforementioned type in order to be able to generate the highest possible pumping power density in the solid body while requiring the smallest possible amount of complexity.
    Type: Grant
    Filed: July 29, 2002
    Date of Patent: May 10, 2005
    Assignee: Universitaet Stuttgart Institut fuer Strahlwerkzeuge
    Inventors: Steffen Erhard, Adolf Giesen, Christian Stewen
  • Patent number: 6891876
    Abstract: An optical system has a diode pump source, and a gain media made of a material with an anisotropic absorption. The gain media is cut at an angle to produce substantially polarization-independent absorption of a pump beam. An optical coupler is positioned between the diode pump source and the gain media. The optical coupler produces a pump beam that has substantially equal amounts of pump power along any two orthogonal axis that are orthogonal to the pump beam in the gain medium. The wavelength range allowed for the pump source is extended.
    Type: Grant
    Filed: August 30, 2002
    Date of Patent: May 10, 2005
    Assignee: Spectra Physics, Inc.
    Inventors: Dirk Sutter, James D. Kafka
  • Patent number: 6888871
    Abstract: A vertical cavity surface emitting laser (VCSEL) device with improved power and beam characteristics. The VCSEL device contains one VCSEL or an array of VCSELs. Each VCSEL has a corresponding integrated microlens, and a heat sink is attached to the device side of the VCSEL device. The heat sink allows improved heat dissipation, and therefore provides improved power characteristics of the VCSEL device output laser beam. The microlens or microlens array allows easier and more compact focussing of the VCSEL device output laser beam. The VCSEL device can be used in a variety of optical systems, and its improved power and focusing characteristics provide a compact, low power, low cost laser system.
    Type: Grant
    Filed: July 12, 2000
    Date of Patent: May 3, 2005
    Assignee: Princeton Optronics, Inc.
    Inventors: Kaiyan Zhang, Jiamin Zhang, Chuni L. Ghosh, Laurence S. Watkins
  • Patent number: 6876684
    Abstract: An organic vertical cavity laser light producing device includes a bottom dielectric stack reflective to light over a predetermined range of wavelengths; an organic active region for producing laser light, and having an organic active region including emissive material; and a top dielectric stack spaced from the bottom dielectric stack and reflective to light over a predetermined range of wavelengths. Pump-beam light is transmitted and introduced into the organic active region through at least one of the dielectric stacks. The organic active region includes one or more periodic gain region(s) and organic spacer layers disposed on either side of the periodic gain region(s) and arranged so that the periodic gain region(s) is aligned with the antinodes of the device's standing wave electromagnetic field, and wherein the spacer layers are substantially transparent to the laser light.
    Type: Grant
    Filed: October 11, 2002
    Date of Patent: April 5, 2005
    Assignee: Eastman Kodak Company
    Inventors: Keith B. Kahen, J. Ramon Vargas, Denis Y. Kondakov, Christopher T. Brown, Lelia Cosimbescu, Viktor Jarikov
  • Patent number: 6873639
    Abstract: In order to effectively solve thermal distortion problems and obtain high-power TEM00-mode operations for DPSS lasers, two major steps are presented in this invention. First, novel multipass pumping approaches and corresponding engineering designs have been developed for slab lasers and thin-disk lasers. They are characterized by using multipass and zig-zag pumping paths and confining pumping beams substantially via total-internal-reflection (TIR) to significantly reduce multiple reflection losses. Second, a zig-zag slab laser in combination with a beam-expanding cavity is employed to realize mode-matching pumping and maximize the energy extraction from laser slabs. It also leads to achieving high-power intracavity frequency conversions over wide spectral ranges and producing red and blue visible lasers with the aid of minimizing spatial hole burning.
    Type: Grant
    Filed: March 15, 2002
    Date of Patent: March 29, 2005
    Inventor: Tong Zhang
  • Patent number: 6847673
    Abstract: Normal incidence stack architecture coupled with the development of diode array pumping enables the power/energy per disk to be increased, a reduction in beam distortions by orders of magnitude, a beam propagation no longer restricted to only one direction of polarization, and the laser becomes so much more amendable to robust packaging.
    Type: Grant
    Filed: June 21, 2002
    Date of Patent: January 25, 2005
    Assignee: The Regents of the University of California
    Inventors: C. Brent Dane, Georg F. Albrecht, Mark D. Rotter
  • Patent number: 6845114
    Abstract: A vertical cavity organic laser device, that includes: an organic laser cavity including: a bottom dielectric stack for receiving and transmitting pump beam light and being reflective to laser light over a predetermined range of wavelengths; an organic active region for receiving transmitted pump beam light from the bottom dielectric stack and for emitting the laser light; a top dielectric stack for reflecting transmitted pump beam light and laser light from the organic active region back into the organic active region, wherein a combination of the bottom and the top dielectric stacks and the organic active region produces the laser light; the device further including an external pump beam light source for optically pumping light to the organic laser cavity; and a positioner for locating the organic laser cavity in a spaced relationship to the external pump beam light source.
    Type: Grant
    Filed: October 16, 2002
    Date of Patent: January 18, 2005
    Assignee: Eastman Kodak Company
    Inventors: David L. Patton, Joseph A. Manico, Edward Covannon, John P. Spoonhower
  • Publication number: 20040258123
    Abstract: A laser gain device (10) holds a laser slab (60) which is pumped by pump energy from at least one diode array assembly (24). An angle at which pump energy from the diode array assembly (24) impinges the laser slab (60) is adjustable via angle adjustment means. The laser slab (60) is mounted between edge bars (62, 64) which have laser slab spacers (84) extending therethrough, allowing laser slabs (60) of different widths to be mounted within the laser gain device (10). One or more pump energy shields (88, 90) are used to control the amount of pump energy entering the laser slab (60), and cooling liquid conduits (100) are provided throughout components of the laser gain device (10), serving to conductively cool a heat shield (12).
    Type: Application
    Filed: June 23, 2003
    Publication date: December 23, 2004
    Inventors: James Michael Zamel, Randall St. Pierre, John A. Szot
  • Patent number: 6834070
    Abstract: The average power output of a laser is scaled, to first order, by increasing the transverse dimension of the gain medium while increasing the thickness of an index matched light guide proportionately. Strategic facets cut at the edges of the laminated gain medium provide a method by which the pump light introduced through edges of the composite structure is trapped and passes through the gain medium repeatedly. Spontaneous emission escapes the laser volume via these facets. A multi-faceted disk geometry with grooves cut into the thickness of the gain medium is optimized to passively reject spontaneous emission generated within the laser material, which would otherwise be trapped and amplified within the high index composite disk. Such geometry allows the useful size of the laser aperture to be increased, enabling the average laser output power to be scaled.
    Type: Grant
    Filed: January 26, 2001
    Date of Patent: December 21, 2004
    Assignee: The Regents of the University of California
    Inventor: Luis E. Zapata
  • Patent number: 6829280
    Abstract: A device (10) for producing high frequency radiation using a source of elliptically polarized radiation is disclosed based on: irradiating a frequency multiplication medium having a screw axis (16) symmetry of approximate Nth order symmetry, oriented so that said elliptically polarized radiation propagates in parallel to the screw axis (16). Also, a method for producing high frequency radiation is disclosed based on irradiating a frequency multiplication medium having a screw axis (16) of approximate Nth order symmetry with elliptically polarized radiation so that the elliptically polarized radiation propagates in parallel to the screw axis (16). Furthermore, a method of producing a beam of high frequency radiation composed of only a limited number of wavelengths is disclosed whereby the intensity of a beam (22) interacting with a frequency multiplication medium is selected so that only a limited number of wavelengths is emitted.
    Type: Grant
    Filed: June 9, 2003
    Date of Patent: December 7, 2004
    Assignee: Technion Research and Development Foundation Ltd.
    Inventors: Ofir Alon, Vitali Averbukh, Nimrod Moiseyev
  • Publication number: 20040233961
    Abstract: An optically pumped semiconductor device has a semiconductor body containing a vertically emitting quantum well structure for generating a vertical radiation field. The quantum well structure contains a plurality of quantum layers between which barrier layers are disposed, and the quantum layers are provided for optically pumping by a pump radiation field. The semiconductor device has a vertical resonator for the pump radiation field with a mirror layer disposed on the semiconductor body, the quantum well structure is disposed in the resonator.
    Type: Application
    Filed: May 24, 2004
    Publication date: November 25, 2004
    Applicant: Osram Opto Semiconductor GmbH
    Inventor: Stephan Lutgen
  • Publication number: 20040218651
    Abstract: An electron-beam excitation laser has a laser structure with a light emitter and reflectors on one hand and an electron source on the other hand, wherein at least part of the light emitter or reflectors has a multidimensional photonic crystal structure. An electron-beam excitation laser includes an electron source emitting electrons and a laser structure consisting of a light emitter and reflectors, accelerates electrons from the electron source, and irradiates the electrons to the laser structure to emit a laser beam from the laser structure, wherein the reflectors and/or the light emitter in the laser structure are formed with multidimensional photonic crystals in which dielectrics with different dielectric constants are arrayed in a plurality of directions at periodic intervals, and one of the dielectrics with different dielectric constants may be formed with a light-emitting material.
    Type: Application
    Filed: June 3, 2004
    Publication date: November 4, 2004
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Tatsuya Iwasaki, Tohru Den
  • Patent number: 6813303
    Abstract: According to the present invention, there is provided a light scattering type particle detector, using a semiconductor laser as a light source, for detecting particles contained in sample fluid which defines a flow path, wherein laser light generated from the semiconductor laser is irradiated to irradiate a region of the flow path with a concave mirror and thereby a particle detecting region is defined. According to the present invention, there is also provided a laser oscillator wherein the optical axis of a semiconductor laser for generating pumping laser light has a predetermined angle with respect to the optical axis of a laser medium for irradiating laser light by pumping. Using such a laser oscillator, laser light irradiated from the laser oscillator is condensed to irradiate a region of a flow path defined by sample fluid, and thereby a particle detecting region is defined. Particles contained in the particle detecting region are detected by receiving scattered light with a light receiving portion.
    Type: Grant
    Filed: January 24, 2002
    Date of Patent: November 2, 2004
    Assignee: Rion Co., Ltd.
    Inventors: Tomonobu Matsuda, Takashi Minakami, Kenji Sasaki, Tsutomu Nakajima
  • Patent number: 6807198
    Abstract: A Laser arrangement (1) comprising a pump unit (2) containing a pumped laser crystal (3), and means, such as a saturable absorber (15), for passive mode-locking, wherein two separate, alternatively switchable resonator arms (11, 12) are provided, one resonator arm (11) of which, which is active in a pulse forming phase (21), comprises the saturable absorber (15), whereas the other resonator arm (12), which is active in an amplifying phase (22), is free from components that introduce losses.
    Type: Grant
    Filed: April 24, 2002
    Date of Patent: October 19, 2004
    Assignee: Femtolasers Produktions GmbH
    Inventors: Alexander Fürbach, Ferenc Krausz
  • Publication number: 20040202221
    Abstract: A laser and method of producing laser light. The laser and method involve passing a high energy beam of particles through an evacuated chamber. A static electric or magnetic field is established in the chamber in a direction that is essentially perpendicular to the direction of propagation of the beam, but which is a periodically varying field in the direction of propagation. The velocity of the particles and the variation in the field is sufficient to pump the particles into a higher energy state and produce laser light at the output of the chamber.
    Type: Application
    Filed: April 10, 2003
    Publication date: October 14, 2004
    Inventor: Robert James Howard
  • Patent number: 6801550
    Abstract: A modified V-groove structure in a double clad laser system permits multiple emitter side pumping of a fiber laser. In one embodiment, a stack of at least five emitters have individual outputs coupled into the inner cladding, with as many sources as desired coupled to the fiber to raise the cumulative pumping power to in excess of 2-KW, thus to achieve a 1-KW fiber laser.
    Type: Grant
    Filed: May 30, 2003
    Date of Patent: October 5, 2004
    Assignee: BAE Systems Information and Electronic Systems Integration Inc.
    Inventors: Kevin J. Snell, Scott D. Setzler
  • Patent number: 6795475
    Abstract: A semiconductor-laser-excited solid-state laser apparatus includes a solid-state laser element and a semiconductor laser unit including a resonator. The solid-state laser element is excited by light emitted from the semiconductor laser unit, and emits laser light. The resonator length in the semiconductor laser unit is arranged to be at least 0.8 mm, so as to reduce an amount of wavelength shift in light emitted from the semiconductor laser unit, and achieve a stable, high-power laser output from the semiconductor-laser-excited solid-state laser apparatus.
    Type: Grant
    Filed: April 19, 2000
    Date of Patent: September 21, 2004
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Hisashi Ohtsuka, Yoji Okazaki
  • Patent number: 6795477
    Abstract: A method for modulating the output of an optically pumped, tunable VCSEL. Two approaches are disclosed. In a first approach, the output of the VCSEL is modulated by modulating the pump laser. In a second approach, the output of the VCSEL is modulated by modulating a voltage applied across the active region.
    Type: Grant
    Filed: August 11, 2000
    Date of Patent: September 21, 2004
    Assignee: Cortek Inc.
    Inventors: Daryoosh Vakhshoori, Parviz Tayebati
  • Patent number: 6785314
    Abstract: There is provided an electric discharge gas laser comprising a housing, a rotating fan, a bearing device and a control. The housing contains a laser gas. The rotating fan is provided in the housing to circulate the gas in the housing. The bearing device magnetically supports a rotating shaft. The bearing device is provided with a sensor device comprising a sensor and a signal processor. The sensor senses the position of the rotating shaft to generate signals indicating the position of the rotating shaft. The signal processor receives and processes the signals delivered from the sensor to output processed signals. The control is separated from the bearing device and is functionally associated with the bearing device to receive the processed signal from the sensor device for controlling the bearing device on the basis of the processed signals.
    Type: Grant
    Filed: June 8, 2001
    Date of Patent: August 31, 2004
    Assignee: Ebara Corporation
    Inventors: Atushi Ooyama, Shinichi Sekiguchi, Hiroyuki Shinozaki, Toshimitsu Barada, Toshiharu Nakazawa
  • Patent number: 6778579
    Abstract: In a solid-state laser in which a gain crystal is polished to have the Brewster angle or a solid-state laser comprising a dichroic concave mirror to which light enters at an incidence angle which is not zero, astigmatism generally occurs in pumping light. By tilting a focusing lens for pumping light with respect to the optical axis of the pumping light, the astigmatism is compensated. The tilting angle is determined in such a manner that synthetic focusing points in the sagittal and tangential planes, of a series optical system of a focusing lens, a dichroic concave lens, and a gain crystal are calculated and the focusing points almost coincide with focusing points in a cavity mode.
    Type: Grant
    Filed: February 28, 2002
    Date of Patent: August 17, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Tatsuya Tomaru, Hrvoje Petek
  • Publication number: 20040151217
    Abstract: A method and devices for generating laser pulse trains for delivery to a target including the use of a single laser generator which produces a plurality of pulse groupings of two or more individual laser pulses within each laser pulse train, generated at selected time intervals. The time intervals between the individual pulses within each of the pulse groupings along with the intervals between pulse groupings themselves are selected and controlled by a controller in reference to several variables including the emission and energy storage lifetimes of the lasing medium, the thermal diffusion time constant of the target, the time required to cool the target after the application of laser pulses to its ambient temperature, and the dissipation time of acoustic waves generated by the pulses.
    Type: Application
    Filed: January 31, 2003
    Publication date: August 5, 2004
    Inventor: Glenn Yeik
  • Patent number: 6771686
    Abstract: By dividing at least the part of the correction optics of at least one row of emitter elements, i.e. the part acting as the fast axis collimator, into several segments, the degradation of beam quality at the focus, especially the widening of the focus, which is caused by the nonconformities between the diode laser bars, or between the row of emitter elements, and the correction optics, can be effectively prevented.
    Type: Grant
    Filed: August 18, 2000
    Date of Patent: August 3, 2004
    Assignee: Laserline Gesellschaft fur Entwicklung und Vertrieb
    Inventors: Christoph Ullman, Volker Krause
  • Patent number: 6738404
    Abstract: A method of controlling a unipolar semiconductor laser in the 4-12 &mgr;m mid-infrared range. This is an optical control method, unlike a purely electrical, power control method which injects a relatively large flux of electrons. The optical control method may advantageously include two optical beams of the same wavelength and a device for making those beams interfere in the active layer of the laser, the optical control beams having a much shorter wavelength than the wavelength of the unipolar laser and having a frequency capable of being modulated more rapidly than that of the laser.
    Type: Grant
    Filed: June 13, 2000
    Date of Patent: May 18, 2004
    Assignee: Thomson-CSF
    Inventors: Vincent Berger, Carlo Sirtori
  • Patent number: 6738407
    Abstract: A solid-state laser rod pumping module has a stack-type semiconductor laser including a plurality of bar-shaped components that are stacked in a direction parallel to the axis of a solid-state laser rod. Each bar-shaped component includes a plurality of laser-light-emitting portions that are aligned and integrated in a direction orthogonal to the axis of the solid-state laser rod. The large divergence angle of the stack-type semiconductor can be compensated by including a light focusing component for focusing laser light emitted out of the stack-type semiconductor laser. The focused light is guided by a laser light guiding component disposed in a diffusive reflection tube. A light guiding component guides the focused light onto a solid-state laser rod located within the diffusive reflective tube, while maintaining the length of one side of the cross section of the guided light.
    Type: Grant
    Filed: April 30, 2003
    Date of Patent: May 18, 2004
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yoshihito Hirano, Shuhei Yamamoto, Yasuharu Koyata, Nicolaie Pavel
  • Patent number: 6731837
    Abstract: A method and apparatus for high power, broad gain, high efficiency, low noise, cladding pumped fiber amplifiers and lasers. The present invention allows a much higher pump light intensity in the inner cladding of a double cladding fiber to be achieved than is possible with conventionally pumped double cladding fiber amplifiers. The present invention utilizes a fiber taper in which the inner cladding decreases from a wide to narrow portion with the fiber core remaining the same diameter.
    Type: Grant
    Filed: December 14, 2001
    Date of Patent: May 4, 2004
    Assignee: Keopsys, Inc.
    Inventors: Lew Goldberg, Marc Le Flohic
  • Patent number: 6728437
    Abstract: An object of the present invention is to prevent an increase of the degree of polarization of an output pumping light even if one of pumping light sources has a failure. Laser diodes (30a, 30b) are composed of FP-LDs made of InGaAsP to laser-oscillate at 1480 nm band. The outputs from the laser diodes (30a, 30b) enter a polarizing beam splitter (32) in orthogonal state of polarization and are combined there. The combined light by the polarizing beam splitter (32) enters a depolarizing element (34) and is depolarized there.
    Type: Grant
    Filed: June 15, 2001
    Date of Patent: April 27, 2004
    Assignee: KDD Submarine Cable Systems Inc.
    Inventors: Noboru Edagawa, Masatoshi Suzuki
  • Patent number: 6714578
    Abstract: The present invention uses a novel crystal host to minimize parasitic upconversion and lifetime quenching processes by increasing the distance between active dopant ions in the matrix. As a result, erbium that could previously only be useful at low levels may now be incorporated at much higher concentrations without adverse effects. In addition, this host has long excited-state-lifetimes, making it more effective as an energy storage device for pulsed laser applications.
    Type: Grant
    Filed: June 6, 2002
    Date of Patent: March 30, 2004
    Inventors: Scott D. Setzler, Peter G. Schunemann, Thomas M. Pollak
  • Patent number: 6707837
    Abstract: Photon flow in an electromagnetic resonator is controlled, in a cavity having reflecting walls, by designing the cavity shape, size, reflectivity and/or medium therein so that the transition probability for the transition of photons between neighboring modes in the range between an initial resonant frequency and a target resonant frequency is larger than the probability for the absorption of photons.
    Type: Grant
    Filed: July 2, 2001
    Date of Patent: March 16, 2004
    Inventor: Eberhard Müller
  • Patent number: 6707832
    Abstract: The present invention provides for the coupling of laser diodes into electromagnetic radiation transmitting fibers wherein coupling efficiency is improved by improving the spatial brightness of multi-mode diode lasers as they are coupled into double-clad fibers. A Bragg grating 100 is fabricated into the core 102 of a double-clad fiber 104 coupled to a multi-mode diode laser 106. The output 108 from the multi-mode diode laser 106 is coupled into the core 102 and inner cladding 110 of the double-clad fiber by proximity or by one or more focusing objectives 112. The Bragg grating 100 in the core 102 of the double-clad fiber 104 is written at the wavelength of the multi-mode diode laser 106. The original output 108 from the multi-mode diode laser 106 strikes the Bragg grating 100 which reflects feedback 114 back to the diode laser 106.
    Type: Grant
    Filed: December 23, 2002
    Date of Patent: March 16, 2004
    Assignee: HRL Laboratories, LLC
    Inventor: Monica Minden
  • Patent number: 6697409
    Abstract: A laser apparatus comprises a beam distributor to distribute a pumping beam over a laser medium. The beam distributor comprises a beam conductor having an incident surface and an intermediate surface smaller than the incident surface. The beam conductor conducts the pumping beam received by the incident surface to the intermediate surface. A main body is connected to the intermediate surface and has a plurality of surfaces and confines the pumping beam introduced through the intermediate surface by repeating total internal reflection at the surfaces. When the intermediate surface becomes small, quantity of the pumping beam escaping from the intermediate surface becomes small. The main body distributes the pumping beam confined therein over the laser medium where the laser medium is in contact with the surfaces of the main body.
    Type: Grant
    Filed: July 21, 2000
    Date of Patent: February 24, 2004
    Assignee: Hoya Corporation
    Inventor: Hiroshi Sekiguchi
  • Patent number: 6693922
    Abstract: The inventive rod includes a gain medium having first and second equal length portions sharing a common optical axis and an optical rotator disposed between said first and second portions which optical rotator compensates for birefringence. In an exemplary case, the optical rotator includes first and second waveplates optically coupled to one another and oriented with respect to one another by a predetermined angle, where the first waveplate receives a polarized beam having a first state, and the second waveplate produces the polarized beam having a second state, the first and second states differing from one another by 90°. Multiple rotators can be employed to compensate strongly birefringent rods, each rotator compensating a section of a rod constructed from a plurality of equal length optical gain elements.
    Type: Grant
    Filed: January 13, 2000
    Date of Patent: February 17, 2004
    Assignee: Raytheon Company
    Inventor: Robin A. Reeder
  • Publication number: 20040028107
    Abstract: This invention relates to the field of lasers and in particular to the pump sources used in lasers. Many existing lasers use linear flashlamps in order to create population inversion in the gain medium of the laser. Such pump sources suffer from a number of drawbacks particularly when pumping dye lasers including explosive damage, long optical pulse length and inappropriate spectral emission. This invention provides a pump source for a laser which exploits the surface discharge phenomenon. A dielectric material (1) which is in contract with a gas (9) has electrical energy discharged across its surface in order to provide an electromagnetic emission which is then used to pump the gain medium. By varying the dielectric material or the cover gas used (amongst other variables) the surface emission can be used to pump the laser gain medium.
    Type: Application
    Filed: February 25, 2003
    Publication date: February 12, 2004
    Inventors: David James Fulker, Mark Ralph Venner, Andrew James Finlayson, Anthony David Case
  • Patent number: 6690705
    Abstract: A method for exciting chemical bonds in molecules using an electromagnetic field includes the step of generating a plurality of electromagnetic oscillation modes. The oscillation modes redistributing respective mode energies between themselves. Energy derived from the redistributed mode energies is used to impart energy to at least one pair of electrons comprising a chemical bond, thus exciting these electrons. The process can be used even when all electrons are paired. The method can be used for synthesizing compounds, quantum mechanical pumping of chemical bonds and for characterization of materials. An apparatus for exciting chemical bonds in molecules using an electromagnetic field includes a structure for generating a plurality of electromagnetic oscillation modes, the oscillation modes redistributing respective mode energies between themselves.
    Type: Grant
    Filed: November 9, 2001
    Date of Patent: February 10, 2004
    Assignee: Vector Enery Corporation
    Inventors: Aleksander Maksimov, Peter Novak
  • Publication number: 20040001523
    Abstract: Feedback from a power monitor sampling a portion of the output beam of an optical resonator is used to control the position of a pump beam relative to a second laser. The pump beam position or orientation is adjusted in response to a dither signal imposed on the position or tilt of an external optic or mirror in order to maximize the efficiency of the second laser in converting pump power to output power. Feedback based on the response of the power monitor is used to control the position or tilt of the mirror or optic to which the dither was applied.
    Type: Application
    Filed: November 20, 2002
    Publication date: January 1, 2004
    Inventors: Kevin Holsinger, John Philip Ekstrand
  • Patent number: 6663785
    Abstract: Embodiments of the present invention are directed to method of fabrication of a broadband emitter array. Embodiments of the present invention may grown a first set of emitters possessing a first quantum well characteristic (e.g., quantum well thickness or composition). A portion of the first set of emitters is removed by etching. In place of the removed emitters, a second set of emitters is regrown with said second set of emitters possessing a different quantum well characteristic. By fabricating the emitters sets in this manner, a unitary emitter array may be fabricated that possesses an increased bandwidth, e.g., the first and second sets of emitters may be associated with different center wavelengths. Embodiments of the present invention may utilize emitter arrays fabricated in this manner in, for example, incoherently beam combined (IBC) lasers and in Raman amplifier systems.
    Type: Grant
    Filed: March 6, 2002
    Date of Patent: December 16, 2003
    Assignee: nLight Photonics Corporation
    Inventors: Zhe Huang, Mark A. Devito, Mike P. Grimshaw, Paul A. Crump, Jason N. Farmer, Mark R. Pratt
  • Patent number: 6665328
    Abstract: An optically pumped laser has a gain medium positioned inside of an optical resonator cavity and disposed about a resonator optical axis. An optical pumping source is positioned outside of the optical resonator cavity. A reflective coupler with a coupler body, and an interior volume passing therethrough is positioned proximal to the optical pumping source. Light from the pumping source passes into an entrance aperture of the reflective coupler to an exit aperture of the reflective coupler positioned distal to the optical pumping source. The interior volume of the reflective coupler is bounded by a reflective surface, an entrance aperture and the exit aperture, and is substantially transparent to radiation from the optical pumping source. The reflective surface has a high reflectivity matched to radiation from the optical pumping source.
    Type: Grant
    Filed: September 22, 1999
    Date of Patent: December 16, 2003
    Assignee: Spectra Physics, Inc.
    Inventors: Jason D. Henrie, William L. Nighan, Jr.
  • Patent number: 6661947
    Abstract: In an optical amplifying technique using remote pumping, an optical transmitting apparatus and an optical repeating apparatus are provided. An optical repeating apparatus comprises a first optical transmitting unit, a first loopback unit, a second optical transmitting unit, a second loopback unit, and four optical couplers, wherein transmission light and reception light are transmitted through one optical fiber cable, whereby the installation cost and maintenance cost of the optical cable are decreased. Disconnect of the optical cable is detected by a monitoring function using pumping light and residual pumping light, whereby reliability and safety of the system are remarkably improved. Additionally, adjustment of the optical output level of the repeating station can be most suitably set according to an actual transmission distance.
    Type: Grant
    Filed: March 13, 2002
    Date of Patent: December 9, 2003
    Assignee: Fujitsu Limited
    Inventor: Katsuhiro Shirai
  • Patent number: 6661568
    Abstract: In a diode-pumped laser amplifier the inventive object is to increase the tolerance of the amplifier arrangement relative to variations of the input parameters significantly, so that fine-tuning is no longer necessary for guaranteeing the stability of the amplifier. Into a laser-active solid-state medium where a thermal lens of a strength which is different in orthogonal planes is generated in consequence of the irradiated pump radiation, a laser beam to be amplified is directed into the laser-active solid-state medium while being focused in the plane with a strong thermal lens, wherein a beam waist that is being generated lies in the area of the thermal lens. The laser amplifier can be used for amplifying the radiation of an oscillator.
    Type: Grant
    Filed: August 24, 2001
    Date of Patent: December 9, 2003
    Assignee: Jenoptik Laser, Optik Systeme GmbH
    Inventors: Guenter Hollemann, Jan Symanowski
  • Patent number: 6650678
    Abstract: A plasma is excited uniformly as a whole over the length of each slot. A laser oscillating apparatus is designed to excite a laser gas in a laser tube (2) by introducing electromagnetic waves into the laser tube through a plurality of slots (10) formed in a waveguide wall and generate a laser beam by resonating the light generated from the laser gas. A least one electrode (13) is placed near the slot (10). By giving a predetermined current density to the electrode (13), the intensity distribution of light generated from the laser gas above the slot (10) is controlled.
    Type: Grant
    Filed: February 24, 2000
    Date of Patent: November 18, 2003
    Assignees: Canon Kabushiki Kaisha
    Inventors: Tadahiro Ohmi, Nobumasa Suzuki, Hiroshi Ohsawa, Nobuyoshi Tanaka, Toshikuni Shinohara, Masaki Hirayama
  • Publication number: 20030193980
    Abstract: A reduced glare imaging system for motor vehicles. The reduced glare imaging system includes at least one imaging device for receiving images. The imaging device receives light signals for image processing in a first operational state and does not receive the light signals for image processing in a second operational state. An electromagnetic detection unit is provided for detecting electromagnetic signals generated by a second imaging system. A synchronization unit is also provided for signaling the imaging device to change operational states in response to a detection of the electromagnetic signals generated by the second imaging system.
    Type: Application
    Filed: May 28, 2003
    Publication date: October 16, 2003
    Inventor: Oleg Matveev
  • Publication number: 20030193981
    Abstract: A reduced glare imaging system for motor vehicles which includes at least one light source capable of modulation. The system also includes a synchronization system which has structure for obtaining a time reference, and a trigger for modulating emissions from the light source. The trigger initiates emission of periodic light pulses from the light source at fixed times relative to the time reference. The fixed times can be randomly selected. The light pulses can have a wavelength in the range of 0.19 &mgr;m to 5 &mgr;m.
    Type: Application
    Filed: May 28, 2003
    Publication date: October 16, 2003
    Inventor: Oleg Matveev