Mode Locked Patents (Class 359/340)
  • Patent number: 11349276
    Abstract: The system and method of using an ultra-short pulse mid and long wave infrared laser. The system is seeded with a 2 ?m laser source having a pulse duration in the femtosecond range. The beam is stretched, to increase the pulse duration, and the beam is amplified, to increase an energy level of the laser beam. Both mid wave IR and long wave IR seed beams are first generated, and then amplified via one or more optical parametric chirped-pulse amplification stages. A compressor may be used to compress one or more of the output beams to achieve high peak power and controllable pulse duration in the output beams. The output beams may then be used to create atmospheric or material effects at km range.
    Type: Grant
    Filed: December 2, 2020
    Date of Patent: May 31, 2022
    Assignee: BAE Systems Information and Electronic Systems Integration Inc.
    Inventors: Peter A. Budni, Alan R. Enman, Yannick C. Morel
  • Patent number: 10408925
    Abstract: A range finder includes a plurality of modulated seed lasers providing light at different wavelengths. Light from the seed lasers is provided to a wideband laser fiber amplifier. A portion of amplified laser light is directed to a first detector. The remainder is transmitted to a target through a collimating lens. Reflections from the target are received by a telescope. A major portion of the returned light is provided to a second detector. A minor portion is provided as feedback to the wideband laser fiber amplifier for stabilization. Outputs from the first and second detector are provided to a processor. Processor analyzes the time delay between the transmitted light and the reflected light to provide a range output. Other embodiments could use adaptive optics and mode hopping range calculations.
    Type: Grant
    Filed: July 19, 2017
    Date of Patent: September 10, 2019
    Inventor: Tariq Manzur
  • Patent number: 9882341
    Abstract: A high power fiber laser system is configured with a pump cascade and a laser cascade. The pump cascade includes a fiber amplifier provided with a MM core which is doped with ions of rare-earth element including either Er or Yb/Er. The MM core of fiber amplifier is configured with a double bottleneck-shaped cross section. The laser cascade has a fiber laser configured with a core which is doped with Tm ions. The pump light generated by the amplifier is coupled into the upstream end of the Tm laser.
    Type: Grant
    Filed: May 3, 2011
    Date of Patent: January 30, 2018
    Assignee: IPG PHOTONICS CORPORATION
    Inventors: Valentin Gapontsev, Fedor Shcherbina, Andrey Mashkin
  • Patent number: 9444215
    Abstract: A high power single mode (“SM”) laser system includes an amplifier configured with a monolithic fiber to rod fiber waveguide which is structured with a multimode (“MM”) core and at least one cladding surrounding the core. The MM core is configured with a small diameter uniform input region receiving and guiding a SM signal light, a mode-transforming frustoconical core region expanding outwards from the input region and a relatively large diameter uniform output portion. The high power laser system is further structured with a MM pump light delivery fiber having a numerical aperture NA2, which is at most equal to that one of the output core portion. The amplifier and pump light output fiber traverse an unconfined delivery cable and terminate upstream from a mirror which is configured to focus the incident pump light into the core of the amplifier in a counter-propagating direction.
    Type: Grant
    Filed: March 6, 2014
    Date of Patent: September 13, 2016
    Assignee: IPG PHOTONICS CORPORATION
    Inventors: Valentin Gapontsev, Igor Samartsev, Dimitri Yagodkin
  • Patent number: 9158177
    Abstract: A supercontinuum optical source comprises a laser source apparatus comprising at least one laser, the laser source apparatus configured for providing first and second signals; a modulator apparatus downstream of at least one laser of the laser source apparatus for modulating at least one of the first and second signals, the modulator apparatus including at least one modulator; a combiner downstream of the modulator apparatus for combining the first and second signals; an amplifier downstream of the combiner for amplifying the first and second signals after combination; a nonlinear element downstream of the amplifier for receiving the first and second signals after amplification, the nonlinear optical element providing spectral broadening responsive to the first signal and wherein the second signal does not substantially contribute to spectral broadening; and an output for outputting spectrally broadened light from the optical supercontinuum source.
    Type: Grant
    Filed: November 24, 2011
    Date of Patent: October 13, 2015
    Assignee: Fianium Ltd.
    Inventors: John Redvers Clowes, Christophe Codemard, Pascal Dupriez
  • Patent number: 9065243
    Abstract: The phase sensitive amplifier according to the present invention is a phase sensitive amplifier that uses the optical mixing using a nonlinear optical effect to amplify the signal light. The phase sensitive amplifier according to the present invention includes: the first second-order nonlinear optical element; and the second second-order nonlinear optical element. The first second-order nonlinear optical element causes the fundamental wave light to generate second harmonic light used as pump light and separates only the second harmonic light. The second second-order nonlinear optical element includes a multiplexer to multiplex the signal light with the second harmonic light and spectrally separates only the amplified signal light. The multiplexed signal light and second harmonic light are used subjected to parametric amplification.
    Type: Grant
    Filed: January 20, 2012
    Date of Patent: June 23, 2015
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Masaki Asobe, Takeshi Umeki, Kouji Enbutsu, Akio Tokura, Yutaka Miyamoto, Hidehiko Takara, Hirokazu Takenouchi, Isao Tomita
  • Publication number: 20150070753
    Abstract: A solid-state MOPA includes a mode-locked laser delivering a train of pulses. The pulses are input to a fast E-O shutter, including polarization-rotating elements, polarizing beam-splitters, and a Pockels cell that can be driven alternatively by high voltage (HV) pulses of fixed long and short durations. A multi-pass amplifier follows the E-O shutter. The E-O shutter selects every Nth pulse from the input train and delivers the selected pulses to the multi-pass amplifier. The multi-pass amplifier returns amplified seed-pulses to the E-O shutter. The shutter rejects or transmits the amplified pulses depending on whether the HV-pulse duration is respectively short or long. Transmitted amplified pulses are delivered to a transient amplifier configured for separately suppressing first-pulse over-amplification and residual pulse leakage.
    Type: Application
    Filed: September 9, 2013
    Publication date: March 12, 2015
    Applicant: COHERENT KAISERSLAUTERN GMBH
    Inventors: Ralf KNAPPE, Albert SEIFERT, Alexander Weis
  • Patent number: 8928863
    Abstract: A system for providing a sliced optical pulse is disclosed. The system can comprise a master oscillator (MO) configured to generate an optical pulse at a first spectral bandwidth. The system can also comprise a semiconductor optical amplifier (SOA) configured to slice the optical pulse to generate a sliced optical pulse that has a second spectral bandwidth. The second spectral bandwidth can be smaller than the first spectral bandwidth.
    Type: Grant
    Filed: May 6, 2011
    Date of Patent: January 6, 2015
    Assignee: Northrop Grumman Systems Corporation
    Inventors: Peter A. Thielen, Eric Cheung, Timothy McComb
  • Publication number: 20140376084
    Abstract: The invention describes classes of robust fiber laser systems usable as pulse sources for Nd: or Yb: based regenerative amplifiers intended for industrial settings. The invention modifies adapts and incorporates several recent advances in FCPA systems to use as the input source for this new class of regenerative amplifier.
    Type: Application
    Filed: September 10, 2014
    Publication date: December 25, 2014
    Applicant: IMRA AMERICA, INC.
    Inventors: Donald J. HARTER, Gyu C. CHO, Zhenlin LIU, Martin E. FERMANN, Xinhua GU, Salvatore F. NATI, Lawrence SHAH, Ingmar HARTL, Mark BENDETT
  • Patent number: 8853604
    Abstract: An Integrated Laser Field Conjugation System (ILFCS) for end-to-end compensation of high-energy laser for propagation through turbulence with non-cooperative target. ILFCS using interferometric slaving technique and stand-alone adaptive optical systems to effect pre-compensation of amplitude and phase aberrations in turbulent medium, providing pre-compensation for aberrations in a laser amplifier. Performing compensation functions in low-power beam paths, increasing capability, reducing cost, reducing size compensation components for phase correction devices. Pre-compensating low-power master oscillator beam for aberrations in both high-power amplifier and turbulent propagation path-to-target with configuration enabling wavefront sensing of aberrations. Can be configured to perform phase compensation, or compensation of phase/amplitude aberrations. Capability to compensate aberrations in master oscillator beam.
    Type: Grant
    Filed: December 7, 2010
    Date of Patent: October 7, 2014
    Inventor: Jeffrey D. Barchers
  • Patent number: 8842361
    Abstract: A mode-locked laser amplifier utilizing free-space optical feedback is provided. The amplifier may tap a portion of the input laser signal and tap a portion of the output laser signal, combine the input and output samples in a free-space coupler to form a feedback laser signal, and couple the feedback laser signal back to the input laser signal. The free-space coupler suppresses higher order modes of the output laser signal. The free-space coupler can be tunable to permit selection of the operating mode of the amplifier. A plurality of amplifiers can be utilized to form a multi-stage mode-locked amplifier system. The composite feedback signal can be coupled back to each amplifier stage to lock the operating mode.
    Type: Grant
    Filed: March 25, 2014
    Date of Patent: September 23, 2014
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Tariq Manzur
  • Patent number: 8711471
    Abstract: A stable, single mode fiber amplifier is described. The amplifier consists of a seed source, a passive single clad multimode fiber, an active double clad multimode fiber or a multimode fiber horn and a semiconductor laser pump source. The passive fiber is packaged on a mandrel with a compound radius of curvature such that high order modes in the fiber are stripped from the core leaving only the fundamental mode. This fiber is then spliced to a multimode active fiber of similar core diameter. By exciting only the fundamental mode of this active fiber, stable single mode amplification is achieved.
    Type: Grant
    Filed: April 9, 2010
    Date of Patent: April 29, 2014
    Assignee: nLight Photonics Corporation
    Inventors: Chang Liu, Jason N. Farmer, Anmol Nijjar, Xiaojun Li
  • Patent number: 8625191
    Abstract: A wavelength-tunable light source apparatus includes a first light source apparatus and a second light source apparatus. The first light source apparatus is capable of changing an oscillation wavelength and includes a resonator. The resonator includes an optical amplification medium for amplifying light and a waveguide having wavelength distribution. The second light source apparatus is connected to the waveguide and configured to introduce pulsed light as modulation light to the first light source apparatus. The oscillation wavelength is controlled by active mode locking employing cross-gain modulation using the modulation light. The pulse width of the modulation light has a duration shorter than a duration of a half period of a driving signal for generating the modulation light.
    Type: Grant
    Filed: January 10, 2011
    Date of Patent: January 7, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Makoto Oigawa, Furusawa Kentaro
  • Publication number: 20130329279
    Abstract: An electronic circuit for controlling a laser system consisting of a pulse source and high power fiber amplifier is disclosed. The circuit is used to control the gain of the high power fiber amplifier system so that the amplified output pulses have predetermined pulse energy as the pulse width and repetition rate of the oscillator are varied. This includes keeping the pulse energy constant when the pulse train is turned on. The circuitry is also used to control the temperature of the high power fiber amplifier pump diode such that the wavelength of the pump diode is held at the optimum absorption wavelength of the fiber amplifier as the diode current is varied. The circuitry also provides a means of protecting the high power fiber amplifier from damage due to a loss of signal from the pulse source or from a pulse-source signal of insufficient injection energy.
    Type: Application
    Filed: August 15, 2013
    Publication date: December 12, 2013
    Applicant: IMRA AMERICA, INC.
    Inventors: Salvatore F. NATI, Otho E. ULRICH, JR., Gyu C. CHO, JR., Wayne A. GILLIS, JR., Donald J. HARTER, JR., Mark BENDETT, JR., Ingmar HARTL, JR.
  • Patent number: 8599889
    Abstract: Pulsed light source comprising pulse generation means (1), such as an optical oscillator, whose output is divided into three arms: two arms (3, 4) to generate a CEP-stable, ultrabroadband idler output; and a third arm (5) to generate a narrowband pump output. The pump output and idler output seed an OPCPA (13), generating stable ultrashort pulses.
    Type: Grant
    Filed: June 14, 2010
    Date of Patent: December 3, 2013
    Assignee: Fundacio Institut de Ciencies Fotoniques
    Inventors: Jens Biegert, Olivier Chalus, Philip Bates
  • Publication number: 20130293941
    Abstract: The invention describes classes of robust fiber laser systems usable as pulse sources for Nd: or Yb: based regenerative amplifiers intended for industrial settings. The invention modifies adapts and incorporates several recent advances in FCPA systems to use as the input source for this new class of regenerative amplifier.
    Type: Application
    Filed: July 5, 2013
    Publication date: November 7, 2013
    Inventors: Donald J. HARTER, Gyu C. CHO, Zhenlin LIU, Martin E. FERMANN, Xinhua GU, Salvatore F. NATI, Lawrence SHAH, Ingmar HARTL, Mark BENDETT
  • Publication number: 20130128341
    Abstract: The invention provides a system for use in an optical communication network to reduce noise comprising means for tapping a low noise signal from said network and a phase sensitive amplifier (PSA) for conditioning said tapped signal by means for removing modulation of the tapped signal to allow for phase locking of the tapped signal. A laser source provides phase locked reference signals to generate at least one pump signal, wherein the at least one pump signal provides correct phase alignment for optimum PSA operation. The invention makes use of injection locked and/or phase locked laser sources in conjunction with low power input tap couplers, or post/mid amplification taps to provide the required phase locked reference signals without degrading the input loss or noise. The use of injection/phase locked local lasers suppresses the detrimental impact of the low tapped power or added noise in the generation of the required pump signals.
    Type: Application
    Filed: December 3, 2010
    Publication date: May 23, 2013
    Applicants: CHALMERS UNIVERSITY OF TECHNOLOGY, University College Cork, National University of Ireland, UNIVERSITY OF SOUTHAMPTON, NATIONAL AND KAPODESTRIAN UNIVERSITY OF ATHENS
    Inventors: Andrew Ellis, Stylianos Sygletos, Peter Andrekson, Antonio Bogris, David Richardson, Dimitris Syvridis
  • Patent number: 8376551
    Abstract: A color combining apparatus has first, second, and third color channels, each color channel having a light source that is energizable to direct light of a corresponding first, second, or third wavelength band, respectively, toward a color combining element. The color combining element is a single piece of a solid, transparent material having at least first and second flat coated surfaces that are noncontiguous. The first coated surface is treated to reflect incident light of the first wavelength band onto an optical axis and to transmit incident light of the second and third wavelength bands. The second coated surface is treated to reflect incident light of the second wavelength band and to transmit incident light of the third wavelength band.
    Type: Grant
    Filed: February 25, 2010
    Date of Patent: February 19, 2013
    Assignee: Corning Incorporated
    Inventor: Joshua Monroe Cobb
  • Publication number: 20120320449
    Abstract: Techniques, devices and systems that stabilize an RF oscillator by using an optical resonator that is stabilized relative to a master RF oscillator with acceptable frequency stability performance. In the examples described, the optical resonator is stabilized relative to the master RF oscillator by using a frequency stability indicator based on two different optical modes of the optical resonator. The RF oscillator to be stabilized is then locked to the stabilized optical resonator to achieve the acceptable RF stability in the RF oscillator.
    Type: Application
    Filed: June 20, 2012
    Publication date: December 20, 2012
    Applicant: OEwaves, Inc.
    Inventors: ANATOLIY A. SAVCHENKOV, Andrey B. Matsko, Lute Maleki, David Seidel, Vladimir S. IIchenko
  • Patent number: 8174609
    Abstract: In a camera module 1 of the present invention, a mechanical shutter 2 is provided above a top surface of a lens unit 3, and a protrusion section formed to an end of a lens 31 is held in a depression section formed on a back surface of the mechanical shutter 2. With the arrangement, it is possible to cause the camera module 1 employing the mechanical shutter 2 to be smaller and thinner at the same time.
    Type: Grant
    Filed: May 22, 2009
    Date of Patent: May 8, 2012
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yoshihiro Sekimoto, Kazuya Fujita, Kiyoharu Shimano, Kenji Sakai
  • Publication number: 20120099185
    Abstract: A laser diode assembly includes a mode-locked laser diode device, where a light output spectrum shows long-wavelength shift by self-phase modulation, an external resonator, and a wavelength selective element. A long wavelength component of a pulsed laser beam emitted through the external resonator from the mode-locked laser diode device is extracted by the wavelength selective element, and output to the outside.
    Type: Application
    Filed: September 29, 2011
    Publication date: April 26, 2012
    Applicants: TOHOKU UNIVERSITY, SONY CORPORATION
    Inventors: Hiroyuki Yokoyama, Shunsuke Kono, Masaru Kuramoto
  • Publication number: 20120008649
    Abstract: A pulsed laser comprises an oscillator and amplifier. An attenuator and/or pre-compressor may be disposed between the oscillator and amplifier to improve performance and possibly the quality of pulses output from the laser. Such pre-compression may be implemented with spectral filters and/or dispersive elements between the oscillator and amplifier. The pulsed laser may have a modular design comprising modular devices that may have Telcordia-graded quality and reliability. Fiber pigtails extending from the device modules can be spliced together to form laser system. In one embodiment, a laser system operating at approximately 1050 nm comprises an oscillator having a spectral bandwidth of approximately 19 nm. This oscillator signal can be manipulated to generate a pulse having a width below approximately 90 fs.
    Type: Application
    Filed: June 14, 2010
    Publication date: January 12, 2012
    Applicant: IMRA AMERICA, INC.
    Inventors: Xinhua Gu, Mark Bendett, Gyu Cheon Cho
  • Publication number: 20100188733
    Abstract: An ultra-short high-power light pulse source including a first laser pump source (1), a mode-locked laser oscillator (2), a second laser pump source (4), a waveguide (6) capable of inserting spectral phases into the light pulses, and a compressor (8) capable of generating predetermined spectral phases into the light pulses. The waveguide (6) includes an element capable of compensating the predetermined spectral phases generated at least by the compressor (8), the second laser pump source (4) being capable of delivering a second pump light flow (5) having a power PL such that the spectral phases generated by the wave guide (6) are opposed or quasi opposed to the predetermined spectral phases generated by the compressor (8) in order to generate compressed ultra-short light pulses (9) at the output of the compressor (8) with a planar or quasi planar spectral phase.
    Type: Application
    Filed: June 13, 2008
    Publication date: July 29, 2010
    Applicants: AMPLITUDE SYSTEMES, INSTITUT D'OPTIQUE GRADUATE SCHOOL,, CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE
    Inventors: Eric Mottay, Patrick Georges, Yoann Zaouter, Marc Hanna, Dimitris Papadopoulos, Frederic Druon, Eric Cormier
  • Patent number: 7763841
    Abstract: Embodiments are disclosed herein related to the construction of optical elements for structured light depth sensor systems. One disclosed embodiment provides a depth sensing system with an optical component comprising a first substrate surface, a first optical element formed in a polymer layer disposed on the first substrate surface, a second substrate surface, and a second optical element formed in a polymer layer disposed on the second substrate surface, wherein the second optical element is optically aligned with the first optical element. The depth sensing further comprises a projector configured to provide light to form a pattern to illuminate a target, and a sensor to acquire an image of the pattern.
    Type: Grant
    Filed: May 27, 2009
    Date of Patent: July 27, 2010
    Assignee: Microsoft Corporation
    Inventor: Scott McEldowney
  • Publication number: 20090244695
    Abstract: Embodiments of parametric chirped pulse amplifiers seeded with a single pulse source which is subsequently split into a signal arm and a pump arm with appropriate signal and pump conditioning stages are disclosed, which advantageously improve the utility of high average power and/or high energy ultrafast amplification systems. In various embodiments, at least one of the signal or the pump conditioning stages is non-linear, allowing for a great range of seed sources to be utilized. Chirped pulse amplification in the pump conditioning stage may be used to simplify the parametric amplification of pulses with pulse widths of the order of 10 fs. The parametric pump can include coherently combined fiber arrays, hybrid fiber solid-state amplifiers, and/or cryogenically cooled solid-state amplifiers to increase or optimize the energy extraction of high average powers.
    Type: Application
    Filed: March 25, 2009
    Publication date: October 1, 2009
    Inventors: Andrius Marcinkevicius, Martin E. Fermann
  • Patent number: 7593145
    Abstract: A shock lockup apparatus is mounted on the chassis of an image scanning device includes a stopping block and a lockup module, with part of the transmission belt driving the chassis of the image scanning device being placed in between. In such a manner, when the image scanning device is being moved and the chassis receives shock or momentum, then the locking unit of the lockup module will move toward the stopping block to clip the transmission belt and fix the chassis synchronously.
    Type: Grant
    Filed: January 30, 2006
    Date of Patent: September 22, 2009
    Assignee: Avision Inc.
    Inventor: Yulun Chang
  • Publication number: 20090174931
    Abstract: A control system for improving and stabilizing Fourier domain mode locking (FDML) operation. The control system may also provide regulation of FDML operational parameters such as filter tuning, laser gain, polarization, polarization chromaticity, elliptical polarization retardance, and/or dispersion. The control system may be located internal to or external from the FDML laser cavity.
    Type: Application
    Filed: October 22, 2008
    Publication date: July 9, 2009
    Inventors: Robert A. Huber, James G. Fujimoto, Desmond C. Adler
  • Patent number: 7440173
    Abstract: A fiber Chirped Pulse Amplification (CPA) laser system includes a fiber mode-locking oscillator for generating a laser for projecting to a fiber stretcher for stretching a pulse width of the laser wherein the stretcher further comprising a self-phase modulation (SPM) assisted photonics crystal fiber (PCF) single mode (SM) fiber stretcher. The fiber CPA laser system further includes a multistage amplifier for amplifying the laser and a high-order dispersion-compensating compressor for compensating high order dispersions and compressing the pulse width of the laser.
    Type: Grant
    Filed: June 30, 2006
    Date of Patent: October 21, 2008
    Assignee: Polar Onyx, Inc.
    Inventors: Jian Liu, Jiangfan Xia
  • Patent number: 6894828
    Abstract: The present invention is directed to guided wave systems, beam transport and waveguide techniques. The invention may comprise passive or active, hollow and dielectric core self-imaging mode wave guide systems, beam amplifiers (10, 40), laser resonators (70), beam transports, and waveguides. Embodiments may include rectangular cross-section waveguides, and preferably maintaining spatial profile of an input beam, such as a Gaussian beam, through the self-imaging period of the waveguide while unique new capabilities to mitigate non-linear distortions that corrupt spatial, spectral and temporal coherence and polarization. Additional aspects may include, for example, transport, amplification, phase/frequency control or modulation, deflection, conversion, synthetic aperture, distributed aperture, beam forming, beam steering, beam combining, power sampling, power combining and power splitting, among other features.
    Type: Grant
    Filed: October 1, 2001
    Date of Patent: May 17, 2005
    Assignee: Coherent Technologies, Inc.
    Inventors: Wayne S. Pelouch, Duane D. Smith, Narasimha S. Prasad
  • Patent number: 6728273
    Abstract: A method and apparatus are provided for increasing the energy of chirped laser pulses to an output in the range 0.001 to over 10 millijoules at a repetition rate 0.010 to 100 kHz by using a two stage optical parametric amplifier utilizing a bulk nonlinear crystal wherein the pump and signal beam size can be independently adjusted in each stage.
    Type: Grant
    Filed: July 31, 2001
    Date of Patent: April 27, 2004
    Assignee: The Regents of the University of California
    Inventor: Michael D. Perry
  • Patent number: 6717719
    Abstract: A multiplexing device using N-stages of double-coated planar glass mirrors or coated mirror pairs to coherently combine the output of 2N narrow-bandwidth, diffraction-limited, polarized, and phase-locked optical beams to produce a single diffraction-limited beam with a power close to 2N times that of a single beam. A multiplexer system is also disclosed to control the relative phases of the 2N beams used in conjunction with the multiplexing device.
    Type: Grant
    Filed: October 1, 2001
    Date of Patent: April 6, 2004
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventor: Gerald T. Moore
  • Patent number: 6697192
    Abstract: An external-resonator laser system having multiple laser elements is configured to permit each laser to undergo individual amplification notwithstanding optical beam combination. In this way, overall output power may be scaled in a desired fashion, depending on the selected characteristics of the optical amplifier elements. To achieve additional power, each of the amplifiers may implemented as a phased array. Viewed more generally, a phased-array configuration affords beam combining in two stages, with each contributing input source itself composed of multiple sources whose outputs have been combined. If each phased-array source emits at a different wavelength, this design offers a multi-wavelength output whose power level may be scaled in accordance with the number and character of the devices forming each phased array.
    Type: Grant
    Filed: November 8, 2000
    Date of Patent: February 24, 2004
    Assignee: Massachusetts Institute of Technology
    Inventors: Tso Yee Fan, Anish Goyal, Antonio Sanchez-Rubio
  • Patent number: 6628454
    Abstract: A bidirectionally pumped optical amplifier comprises an active fibre having two ends, a first WDM coupler and a second WDM coupler coupled to said ends, a first pump branch coupled to said first WDM coupler comprising a first laser and a grating, for introducing pump radiation in said active fibre in a first direction, and a second pump branch coupled to said second WDM coupler comprising a second laser, for introducing pump radiation in said active fibre in a second direction, opposite to said first direction. A portion of unabsorbed pump residual propagating in the first direction is coupled in one of the two pump branches towards the pump laser included in the pump branch, and locks the emission wavelength of the pump laser. The other pump branch preferably comprises an optical isolator for the pump radiation. Preferably, the pump lasers emit in the 980 nm window.
    Type: Grant
    Filed: March 4, 2002
    Date of Patent: September 30, 2003
    Assignee: Corning Oti SpA
    Inventors: Giorgio Ghislotti, Stefano Balsamo, Fiorenzo Trezzi
  • Patent number: 6621615
    Abstract: A light-modulating system, includes: a light source for emitting a sequence of light pulses at a period Tp; a light modulator having a variable-width switching profile with rise and fall times Tr and Tf respectively, wherein the greater of Tr and Tf is greater than Tp, the light modulator modulating the sequence of light pulses; and a controller for controlling the width of the variable-width light switching profile.
    Type: Grant
    Filed: March 19, 2002
    Date of Patent: September 16, 2003
    Assignee: Eastman Kodak Company
    Inventors: Brian E. Kruschwitz, Marek W. Kowarz, Reinhold Thiel
  • Patent number: 6483629
    Abstract: An optical window signal generator which begins generation of an optical output signal in response to an optical activation pulse, and terminates generation of the optical output signal in response to an optical deactivation pulse. The rise time of the optical output signal is equal to the rise time of the optical activation pulse, and its fall time is equal to the rise time of the optical deactivation pulse.
    Type: Grant
    Filed: December 22, 1998
    Date of Patent: November 19, 2002
    Assignee: Corning O.T.I., Inc.
    Inventors: Pierpaolo Boffi, Lucia Marazzi, Mario Martinelli, Paola Parolari
  • Patent number: 6233085
    Abstract: The present invention provides several apparatus, methods, and computer program products for phase shifts in an optical signal generated by an optical device. The present invention includes a optical phase modulator for altering the phase of the optical signals output by an optical device. The present invention also includes a detector assembly that receives an interference signal generated by an optical interference of a power signal and a reference signal. The detector assembly generates a lockin signal representing the optical phase difference between the power signal and the reference signal. Connected to both the detector assembly and the optical phase detector is a processor. The processor receives the lockin signal from the detector assembly and compares the lockin signal to at least one predetermined set point value. The predetermined set point value represents either a desired maximum lockin signal value or a range of acceptable lockin values.
    Type: Grant
    Filed: October 19, 1999
    Date of Patent: May 15, 2001
    Assignee: The Boeing Company
    Inventor: Bartley C. Johnson
  • Patent number: 5872649
    Abstract: The gain provided by an erbium amplifier is stabilised by spectrally selective optical feedback to make the amplifier lase. The resulting laser emission is extracted from the amplifier output using a Mach Zehnder with matched Bragg reflectors in its two interference arms. The extracted light may be used for supervisory purposes. Part of the laser cavity defining feedback may be provided by the Mach Zehnder by arranging one of its Bragg reflectors to be displaced with respect to the other.
    Type: Grant
    Filed: December 4, 1996
    Date of Patent: February 16, 1999
    Assignee: Northern Telecom Limited
    Inventors: Kevin Christopher Bryon, Kate Sugden
  • Patent number: 5818630
    Abstract: To amplify and compress optical pulses in a multi-mode (MM) optical fiber, a single-mode is launched into the MM fiber by matching the modal profile of the fundamental mode of the MM fiber with a diffraction-limited optical mode at the launch end. The fundamental mode is preserved in the MM fiber by minimizing mode-coupling by using relatively short lengths of step-index MM fibers with a few hundred modes and by minimizing fiber perturbations. Doping is confined to the center of the fiber core to preferentially amplify the fundamental mode, to reduce amplified spontaneous emission and to allow gain-guiding of the fundamental mode. Gain-guiding allows for the design of systems with length-dependent and power-dependent diameters of the fundamental mode. To allow pumping with high-power laser diodes, a double-clad amplifier structure is employed. For applications in nonlinear pulse-compression, self phase modulation and dispersion in the optical fibers can be exploited.
    Type: Grant
    Filed: June 25, 1997
    Date of Patent: October 6, 1998
    Assignee: Imra America, Inc.
    Inventors: Martin E. Fermann, Donald J. Harter
  • Patent number: 5812308
    Abstract: A laser system has a high reflector and an output coupler defining a laser cavity with an optical axis. Included is a pump source, a mode-locking apparatus and at least one fold mirror positioned in the laser cavity along the optical axis. A gain media is positioned adjacent to the fold mirror. The gain media has an overlap region where an intracavity beam entering the gain media substantially overlaps the intracavity beam exiting the gain media.
    Type: Grant
    Filed: December 20, 1995
    Date of Patent: September 22, 1998
    Assignee: Spectra Physics Lasers, Inc.
    Inventors: James D. Kafka, Jan-Willem Pieterse
  • Patent number: 5646774
    Abstract: This invention is an improvement of a mode-locked laser stabilizing method and apparatus used with a mode-locked laser apparatus which comprises an optical cavity which consists of an optical modulator which modulates the loss or the phase of light at a fixed frequency, an optical delay line to electrically change the optical path length of the cavity, and an optical amplifier which amplifies a modulated optical pulses. In this method, at least one of the relaxation oscillation frequency components and the harmonic components in the output optical pulses of the mode-locked laser are extracted, and a process of controlling the optical delay line by using the extracted frequency component as an error signal for feedback control and to suppress the error signal below a fixed value.
    Type: Grant
    Filed: January 16, 1996
    Date of Patent: July 8, 1997
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Hidehiko Takara, Satoki Kawanishi, Masatoshi Saruwatari
  • Patent number: 5309453
    Abstract: A system for providing a single pulse of laser oscillator radiation of broad spectral range operative to excite a plurality of modes of a ring laser operating as an injection locked oscillator. In order to provide injection locking of the ring oscillator at multiple modes, a pump laser for the laser oscillator has its cavity length substantially similar to that of the laser oscillator thereby producing partial mode locking of the laser oscillator by amplitude modulation of the pump laser. In this manner the laser oscillator provides a single pulse of mode rich frequencies which are chosen within the band desired in the ring laser. This pulse continuously circulates within the cavity of the laser oscillator. The output of the laser oscillator through an output mirror thus forms a series of pulses separated in time by the roundtrip delay of the laser oscillator cavity. A single such pulse is selected by Pockels cell gating for injection into the ring oscillator.
    Type: Grant
    Filed: July 27, 1981
    Date of Patent: May 3, 1994
    Assignee: Jersey Nuclear-Avco Isotopes, Inc.
    Inventor: Edmond B. Treacy
  • Patent number: RE45177
    Abstract: Use of quasi-phase-matched (QPM) materials for parametric chirped pulse amplification (PCPA) substantially reduces the required pump peak power and pump brightness, allowing exploitation of spatially-multimode and long duration pump pulses. It also removes restrictions on pump wavelength and amplification bandwidth. This allows substantial simplification in pump laser design for a high-energy PCPA system and, consequently, the construction of compact diode-pumped sources of high-energy ultrashort optical pulses. Also, this allows elimination of gain-narrowing and phase-distortion limitations on minimum pulse duration, which typically arise in a chirped pulse amplification system. One example of a compact source of high-energy ultrashort pulses is a multimode-core fiber based PCPA system. Limitations on pulse energy due to the limited core size for single-mode fibers are circumvented by using large multimode core.
    Type: Grant
    Filed: March 26, 2003
    Date of Patent: October 7, 2014
    Assignee: IMRA America, Inc.
    Inventors: Almantas Galvanauskas, Donald Harter, Gregg Sucha