Patents by Inventor Yeung-Lak Lee

Yeung-Lak Lee 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: 9979153
    Abstract: Disclosed herein is an optical fiber laser device including a seed unit for providing at least two seed lights having different wavelengths; and an amplifying unit for amplifying the at least two seed lights. The amplifying unit includes: a preamplifying unit for amplifying the at least two seed lights by using excitation light of which the wavelength is shorter than the wavelengths of the seed lights; and a final amplifying unit to which no separate excitation light source is provided. The final amplifying unit amplifies the seed light having the longest wavelength by using the other seed light as excitation light with respect to the seed light having the longest wavelength among the at least two seed light.
    Type: Grant
    Filed: February 9, 2015
    Date of Patent: May 22, 2018
    Assignee: GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Bong Ahn Yu, Young Chul Noh, Woo Jin Shin, Chang soo Jung, Yeung Lak Lee
  • Publication number: 20170063019
    Abstract: Disclosed herein is an optical fiber laser device including a seed unit for providing at least two seed lights having different wavelengths; and an amplifying unit for amplifying the at least two seed lights. The amplifying unit includes: a preamplifying unit for amplifying the at least two seed lights by using excitation light of which the wavelength is shorter than the wavelengths of the seed lights; and a final amplifying unit to which no separate excitation light source is provided. The final amplifying unit amplifies the seed light having the longest wavelength by using the other seed light as excitation light with respect to the seed light having the longest wavelength among the at least two seed light.
    Type: Application
    Filed: February 9, 2015
    Publication date: March 2, 2017
    Inventors: Bong Ahn YU, Young Chul NOH, Woo Jin SHIN, Chang soo JUNG, Yeung Lak LEE
  • Patent number: 9543732
    Abstract: Disclosed is a laser wavelength conversion apparatus. The apparatus includes a focusing lens formed of a birefringent material and configured to have a same refractive index for an infrared laser beam and a green laser beam having different polarization directions and focus the infrared laser beam and the green laser beam without a chromatic aberration, and a sum frequency generator configured to combine the infrared laser beam and the green laser beam focused by the focusing lens to generate an ultraviolet laser beam. The apparatus of the present invention can solve a problem due to a chromatic aberration of the focusing lens, thereby improving a wavelength conversion efficiency and a beam quality.
    Type: Grant
    Filed: September 8, 2014
    Date of Patent: January 10, 2017
    Assignee: GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Changsoo Jung, Young-Chul Noh, Bong-Ahn Yu, Woo Jin Shin, Yeung Lak Lee
  • Patent number: 9461436
    Abstract: The present invention relates to a pulse laser device, and more particularly, to a pulse laser device which can be operated in a burst mode, in which the output of a low-output laser generator is adjusted so as to enable the uniform control of the profile of the peak output of a final output optical pulse train, and in a variable burst mode, in which the profile of the final output optical pulse train can be controlled into an arbitrary waveform.
    Type: Grant
    Filed: October 28, 2013
    Date of Patent: October 4, 2016
    Assignee: GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Young-Chul Noh, Woojin Shin, Bong-Ahn Yu, Yeung Lak Lee, Changsoo Jung
  • Patent number: 9450368
    Abstract: The present invention relates to a pulse laser device, and more particularly, to a pulse laser device which can be operated in a burst mode, in which the output of a low-output laser generator is adjusted so as to enable the uniform control of the profile of the peak output of a final output optical pulse train, and in a variable burst mode, in which the profile of the final output optical pulse train can be controlled into an arbitrary waveform.
    Type: Grant
    Filed: December 13, 2011
    Date of Patent: September 20, 2016
    Assignee: GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Young-Chul Noh, Woojin Shin, Bong-Ahn Yu, Yeung Lak Lee, Changsoo Jung
  • Patent number: 9077147
    Abstract: Disclosed is a burst mode oscillation method for burst mode oscillation by controlling the peak output of light pulses in a laser system. The burst mode oscillation apparatus includes a seed beam generator which receives electrical input signals having different pulse widths, modulates pulse widths and amplitudes of outputs in output light according to the received electrical input signals, and outputs the modulated pulse light, an amplifier which amplifies the modulated pulse light and outputs amplified pulse light, and a non-linear wavelength converter which can control wavelength-converted output light according to the amplitudes of the peak output changed through the pulse widths of the amplified pulse light.
    Type: Grant
    Filed: October 12, 2011
    Date of Patent: July 7, 2015
    Assignee: Gwangju Institute of Science and Technology
    Inventors: Woojin Shin, Young-Chul Noh, Bong-Ahn Yu, Yeung Lak Lee
  • Publication number: 20150071313
    Abstract: Disclosed is a laser wavelength conversion apparatus. The apparatus includes a focusing lens formed of birefringent material and configured to have same refractive index for an infrared laser beam and a green laser beam having different polarization direction and focus the infrared laser beam and the green laser beam without chromatic aberration, and a sum frequency generator configured to combine the infrared laser beam and the green laser beams focused by the focusing lens to generate an ultraviolet laser beam. The apparatus of the present invention can solve a problem due to chromatic aberration of the focusing lens, thereby improving wavelength conversion efficiency and beam quality.
    Type: Application
    Filed: September 8, 2014
    Publication date: March 12, 2015
    Inventors: Changsoo JUNG, Young-Chul NOH, Bong-Ahn YU, Woo Jin SHIN, Yeung Lak LEE
  • Publication number: 20140177033
    Abstract: The present invention relates to a pulse laser device, and more particularly, to a pulse laser device which can be operated in a burst mode, in which the output of a low-output laser generator is adjusted so as to enable the uniform control of the profile of the peak output of a final output optical pulse train, and in a variable burst mode, in which the profile of the final output optical pulse train can be controlled into an arbitrary waveform.
    Type: Application
    Filed: October 28, 2013
    Publication date: June 26, 2014
    Applicant: GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Young-Chul NOH, Woojin SHIN, Bong-Ahn YU, Yeung Lak LEE, Changsoo JUNG
  • Publication number: 20140049811
    Abstract: The present invention relates to a pulse laser device, and more particularly, to a pulse laser device which can be operated in a burst mode, in which the output of a low-output laser generator is adjusted so as to enable the uniform control of the profile of the peak output of a final output optical pulse train, and in a variable burst mode, in which the profile of the final output optical pulse train can be controlled into an arbitrary waveform.
    Type: Application
    Filed: December 13, 2011
    Publication date: February 20, 2014
    Applicant: GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Young-Chul Noh, Woojin Shin, Bong-Ahn Yu, Yeung Lak Lee, Changsoo Jung
  • Publication number: 20130215494
    Abstract: Disclosed is a burst mode oscillation method for burst mode oscillation by controlling the peak output of light pulses in a laser system. The burst mode oscillation apparatus includes a seed beam generator which receives electrical input signals having different pulse widths, modulates pulse widths and amplitudes of outputs in output light according to the received electrical input signals, and outputs the modulated pulse light, an amplifier which amplifies the modulated pulse light and outputs amplified pulse light, and a non-linear wavelength converter which can control wavelength-converted output light according to the amplitudes of the peak output changed through the pulse widths of the amplified pulse light.
    Type: Application
    Filed: October 12, 2011
    Publication date: August 22, 2013
    Applicant: GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Woojin Shin, Young-Chul Noh, Bong-Ahn Yu, Yeung Lak Lee
  • Patent number: 8275009
    Abstract: The present invention relates to a green laser generation device which can be applied to a cellular phone, and more particularly to a green laser generation device which is ultra compact in size having volume of 1 cc or less, despite having a built-in thermo electric cooler, and has sufficient output power, despite having low power consumption, and a portable electronic machine having a laser projection display using the said device. The present invention provides a green laser generation device comprising an LD pump constituted by a photo diode; a fundamental generator generating infrared light laser according to the driving of the LD pump; a second harmonic generator generating green light using the generated infrared light laser; a polarization maintenance unit inserted between the fundamental generator and the second harmonic generator to maintain the polarization of the laser; and a temperature controller controlling an internal temperature of the green laser generation device.
    Type: Grant
    Filed: October 13, 2008
    Date of Patent: September 25, 2012
    Assignee: Gwangju Institute of Science and Technology
    Inventors: Nan-Ei Yu, Do-Kyeong Ko, Chang-Soo Jung, Yeung-Lak Lee, Bong-Ahn Yu, Jeong-Soo Kim
  • Publication number: 20100290488
    Abstract: The present invention relates to a green laser generation device which can be applied to a cellular phone, and more particularly to a green laser generation device which is ultra compact in size having volume of 1 cc or less, despite having a built-in thermo electric cooler, and has sufficient output power, despite having low power consumption, and a portable electronic machine having a laser projection display using the said device. The present invention provides a green laser generation device comprising an LD pump constituted by a photo diode; a fundamental generator generating infrared light laser according to the driving of the LD pump; a second harmonic generator generating green light using the generated infrared light laser; a polarization maintenance unit inserted between the fundamental generator and the second harmonic generator to maintain the polarization of the laser; and a temperature controller controlling an internal temperature of the green laser generation device.
    Type: Application
    Filed: October 13, 2008
    Publication date: November 18, 2010
    Applicant: GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Do-Kyung Ko, Nan-Ei Yu, Chang-Soo Jung, Yeung-Lak Lee, Bong-Ahn Yu