Patents by Inventor Gyu C. Cho

Gyu C. Cho has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10256597
    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: Grant
    Filed: February 22, 2017
    Date of Patent: April 9, 2019
    Assignee: 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
  • Publication number: 20170179676
    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: February 22, 2017
    Publication date: June 22, 2017
    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: 9680280
    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: Grant
    Filed: August 15, 2013
    Date of Patent: June 13, 2017
    Assignee: IMRA AMERICA, INC.
    Inventors: Salvatore F. Nati, Otho E. Ulrich, Jr., Gyu C. Cho, Wayne A. Gillis, Donald J. Harter, Mark Bendett, Ingmar Hartl
  • Patent number: 9590386
    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: Grant
    Filed: September 10, 2014
    Date of Patent: March 7, 2017
    Assignee: 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
  • Publication number: 20160067822
    Abstract: Methods, devices, and systems for ultrashort pulse laser processing of optically transparent materials are disclosed, with example applications in scribing, marking, welding, and joining. For example, ultrashort laser pulses create scribe features with one pass of the laser beam across the material, with at least one of the scribe features being formed below the surface of the material. Slightly modifying the ultrashort pulse laser processing conditions produces sub-surface marks. When properly arranged, these marks are clearly visible with correctly aligned illumination. Reflective marks may also be formed with control of laser parameters. A transparent material other than glass may be utilized. A method for welding transparent materials uses ultrashort laser pulses to create a bond through localized heating.
    Type: Application
    Filed: August 13, 2015
    Publication date: March 10, 2016
    Applicant: IMRA AMERICA, INC.
    Inventors: Alan Y. ARAI, Gyu C. CHO, Jingzhou XU, Fumiyo YOSHINO, Haibin ZHANG, James BOVATSEK, Makoto YOSHIDA
  • Patent number: 9138913
    Abstract: Methods, devices, and systems for ultrashort pulse laser processing of optically transparent materials are presented, with example applications in scribing, marking, welding, and joining. For example, ultrashort laser pulses create multiple scribe features with one pass of the laser beam across the material, with at least one of the scribe features being formed below the surface of the material. Slightly modifying the ultrashort pulse laser processing conditions produces different types of sub-surface marks. When properly arranged, these marks are clearly visible with correctly aligned illumination through either light scattering or light reflection and nearly invisible without illumination. Transparent material other than glass may be utilized. A method for welding transparent materials uses ultrashort laser pulses to create a bond through localized heating.
    Type: Grant
    Filed: March 4, 2009
    Date of Patent: September 22, 2015
    Assignee: IMRA AMERICA, INC.
    Inventors: Alan Y. Arai, Gyu C. Cho, Jingzhou Xu, Fumiyo Yoshino, Haibin Zhang, James Bovatsek, Makoto Yoshida
  • Publication number: 20150255942
    Abstract: By compensating polarization mode-dispersion as well chromatic dispersion in photonic crystal fiber pulse compressors, high pulse energies can be obtained from all-fiber chirped pulse amplification systems. By inducing third-order dispersion in fiber amplifiers via self-phase modulation, the third-order chromatic dispersion from bulk grating pulse compressors can be compensated and the pulse quality of hybrid fiber/bulk chirped pulse amplification systems can be improved. Finally, by amplifying positively chirped pulses in negative dispersion fiber amplifiers, a low noise wavelength tunable seed source via anti-Stokes frequency shifting can be obtained.
    Type: Application
    Filed: May 19, 2015
    Publication date: September 10, 2015
    Applicant: IMRA AMERICA, INC.
    Inventors: Martin E. FERMANN, Gennady IMESHEV, Gyu C. CHO, Zhenlin LIU, Donald J. HARTER
  • Patent number: 9042004
    Abstract: By compensating polarization mode-dispersion as well chromatic dispersion in photonic crystal fiber pulse compressors, high pulse energies can be obtained from all-fiber chirped pulse amplification systems. By inducing third-order dispersion in fiber amplifiers via self-phase modulation, the third-order chromatic dispersion from bulk grating pulse compressors can be compensated and the pulse quality of hybrid fiber/bulk chirped pulse amplification systems can be improved. Finally, by amplifying positively chirped pulses in negative dispersion fiber amplifiers, a low noise wavelength tunable seed source via anti-Stokes frequency shifting can be obtained.
    Type: Grant
    Filed: July 8, 2013
    Date of Patent: May 26, 2015
    Assignee: IMRA AMERICA, INC.
    Inventors: Martin E. Fermann, Gennady Imeshev, Gyu C. Cho, Zhenlin Liu, Donald J. Harter
  • 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: 8855151
    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: Grant
    Filed: July 5, 2013
    Date of Patent: October 7, 2014
    Assignee: 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: 8773754
    Abstract: An optimized Yb: doped fiber mode-locked oscillator and fiber amplifier system for seeding Nd: or Yb: doped regenerative amplifiers. The pulses are generated in the Yb: or Nd: doped fiber mode-locked oscillator, and may undergo spectral narrowing or broadening, wavelength converting, temporal pulse compression or stretching, pulse attenuation and/or lowering the repetition rate of the pulse train. The conditioned pulses are subsequently coupled into an Yb: or Nd: fiber amplifier. The amplified pulses are stretched before amplification in the regenerative amplifier that is based on an Nd: or Yb: doped solid-state laser material, and then recompressed for output.
    Type: Grant
    Filed: March 22, 2011
    Date of Patent: July 8, 2014
    Assignee: IMRA America, Inc.
    Inventors: Donald J. Harter, Gyu C. Cho, Martin E. Fermann, Ingmar Hartl
  • 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.
  • 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: 20130293947
    Abstract: By compensating polarization mode-dispersion as well chromatic dispersion in photonic crystal fiber pulse compressors, high pulse energies can be obtained from all-fiber chirped pulse amplification systems. By inducing third-order dispersion in fiber amplifiers via self-phase modulation, the third-order chromatic dispersion from bulk grating pulse compressors can be compensated and the pulse quality of hybrid fiber/bulk chirped pulse amplification systems can be improved. Finally, by amplifying positively chirped pulses in negative dispersion fiber amplifiers, a low noise wavelength tunable seed source via anti-Stokes frequency shifting can be obtained.
    Type: Application
    Filed: July 8, 2013
    Publication date: November 7, 2013
    Inventors: Martin E. Fermann, Gennady Imeshev, Gyu C. Cho, Zhenlin Liu, Donald J. Harter
  • Patent number: 8509270
    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: Grant
    Filed: December 21, 2011
    Date of Patent: August 13, 2013
    Assignee: IMRA America, Inc.
    Inventors: Donald J. Harter, Gyu C. Cho, Zhenlin Liu, Martin E. Fermann, Xinhu Gu, Salvatore F. Nati, Lawrence Shah, Ingmar Hartl, Mark Bendett
  • Patent number: 8503069
    Abstract: By compensating polarization mode-dispersion as well chromatic dispersion in photonic crystal fiber pulse compressors, high pulse energies can be obtained from all-fiber chirped pulse amplification systems. By inducing third-order dispersion in fiber amplifiers via self-phase modulation, the third-order chromatic dispersion from bulk grating pulse compressors can be compensated and the pulse quality of hybrid fiber/bulk chirped pulse amplification systems can be improved. Finally, by amplifying positively chirped pulses in negative dispersion fiber amplifiers, low noise wavelength tunable seed source via anti-Stokes frequency shifting can be obtained.
    Type: Grant
    Filed: August 5, 2010
    Date of Patent: August 6, 2013
    Assignee: IMRA America, Inc.
    Inventors: Martin E. Fermann, Gennady Imeshev, Gyu C. Cho, Zhenlin Liu, Donald J. Harter
  • Patent number: 8228597
    Abstract: By compensating polarization mode-dispersion as well chromatic dispersion in photonic crystal fiber pulse compressors, high pulse energies can be obtained from all-fiber chirped pulse amplification systems. By inducing third-order dispersion in fiber amplifiers via self-phase modulation, the third-order chromatic dispersion from bulk grating pulse compressors can be compensated and the pulse quality of hybrid fiber/bulk chirped pulse amplification systems can be improved. Finally, by amplifying positively chirped pulses in negative dispersion fiber amplifiers, low noise wavelength tunable seed source via anti-Stokes frequency shifting can be obtained.
    Type: Grant
    Filed: July 15, 2008
    Date of Patent: July 24, 2012
    Assignee: IMRA America, Inc.
    Inventors: Martin E. Fermann, Gennady Imeshev, Gyu C. Cho, Zhenlin Liu, Donald J. Harter
  • Patent number: 8073036
    Abstract: A laser head generating ultrashort pulses is integrated with an active beam steering device in the head. Direct linkage with an application system by means of an adequate interface protocol enables the active device to be controlled directly by the application system.
    Type: Grant
    Filed: December 13, 2010
    Date of Patent: December 6, 2011
    Assignee: Imra America, Inc.
    Inventors: Gyu C. Cho, Oleg Bouevitch
  • Publication number: 20110200061
    Abstract: An optimized Yb: doped fiber mode-locked oscillator and fiber amplifier system for seeding Nd: or Yb: doped regenerative amplifiers. The pulses are generated in the Yb: or Nd: doped fiber mode-locked oscillator, and may undergo spectral narrowing or broadening, wavelength converting, temporal pulse compression or stretching, pulse attenuation and/or lowering the repetition rate of the pulse train. The conditioned pulses are subsequently coupled into an Yb: or Nd: fiber amplifier. The amplified pulses are stretched before amplification in the regenerative amplifier that is based on an Nd: or Yb: doped solid-state laser material, and then recompressed for output.
    Type: Application
    Filed: March 22, 2011
    Publication date: August 18, 2011
    Applicant: IMRA AMERICA, INC.
    Inventors: Donald J. HARTER, Gyu C. CHO, Martin E. FERMANN, Ingmar HARTL
  • Publication number: 20110103408
    Abstract: A laser head generating ultrashort pulses is integrated with an active beam steering device in the head. Direct linkage with an application system by means of an adequate interface protocol enables the active device to be controlled directly by the application system.
    Type: Application
    Filed: December 13, 2010
    Publication date: May 5, 2011
    Applicant: IMRA AMERICA, INC.
    Inventors: Gyu C. CHO, Oleg BOUEVITCH