Patents by Inventor Joong Seon Choe

Joong Seon Choe 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: 9201169
    Abstract: An optical waveguide for optical interconnection including a polymer sheet comprising a crosslinked product of a prepolymer, the prepolymer prepared by condensation reaction between a first compound represented by the formula Ar—H, where Ar comprises (a) a crosslinkable moiety at one end, (b) a moiety selected from the group consisting of —O—, —S—, —COO—, —CO—, —COS—, —SO2—, and —NH—, and (c) one or two repeating units selected from the group consisting of: where A is carbon or nitrogen, and X is hydrogen or halogen; and a second compound consisting of an aromatic moiety.
    Type: Grant
    Filed: April 8, 2014
    Date of Patent: December 1, 2015
    Assignee: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Seung Koo Park, Jung Jin Ju, Suntak Park, Jong-Moo Lee, Min-su Kim, Jin Tae Kim, Joong-Seon Choe
  • Patent number: 9166680
    Abstract: Provided is an apparatus and method for measuring IQ imbalance, and in particular, is an apparatus and method for measuring IQ imbalance for an optical receiver. The apparatus for measuring IQ imbalance for an optical receiver includes a light generating unit generating optical and reference signals to provide the optical and reference signals to an optical receiver, a graph creating unit creating a Lissajous figure by using an in-phase (I) signal and a quadrature-phase (Q) signal output from the optical receiver in response to the optical and reference signals, and a calculating unit calculating IQ imbalance for the optical receiver with reference to the Lissajous figure.
    Type: Grant
    Filed: September 16, 2013
    Date of Patent: October 20, 2015
    Assignee: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Chun Ju Youn, Jong-Hoi Kim, Joong-Seon Choe, Duk Jun Kim, Yong-Hwan Kwon, Eun Soo Nam
  • Patent number: 9031421
    Abstract: Provided is a method of measuring signal transmission time difference of a measuring device. The measuring device according to embodiments, by measuring a skew on two optical paths through signal delays of sufficient sizes for skew measurement on the optical paths, even a skew having a minute size can be measured within a measurable range.
    Type: Grant
    Filed: July 3, 2013
    Date of Patent: May 12, 2015
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Joong-Seon Choe, Chun Ju Youn, Jong-Hoi Kim, Duk Jun Kim, Yong-Hwan Kwon, Kwang-Seong Choi, Eun Soo Nam
  • Patent number: 8929731
    Abstract: An apparatus for measuring performance of a coherent optical receiver includes a beam splitter splitting light into first and second paths, a first optical modulator modulating the first path light, a variable optical attenuator controlling an optical power of the first optical modulator, a first polarization controller transmitting a signal controlling polarization of an output of the variable optical attenuator to the coherent optical receiver, a second optical modulator modulating the second path light, a variable optical delay line delaying time of an output of the second optical modulator, a second polarization controller transmitting a signal controlling polarization of an output of the variable optical delay line to the coherent optical receiver, a network analyzer measuring performance of the coherent optical receiver and controlling the optical modulators, and a controller transmitting a control signal to the optical modulators.
    Type: Grant
    Filed: November 28, 2012
    Date of Patent: January 6, 2015
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Chun Ju Youn, Joong-Seon Choe, Jong-Hoi Kim, Duk Jun Kim, Yong-Hwan Kwon, Eun Soo Nam
  • Publication number: 20140219625
    Abstract: An optical waveguide for optical interconnection including a polymer sheet comprising a crosslinked product of a prepolymer, the prepolymer prepared by condensation reaction between a first compound represented by the formula Ar—H, where Ar comprises (a) a crosslinkable moiety at one end, (b) a moiety selected from the group consisting of —O—, —S—, —COO—, —CO—, —COS—, —SO2—, and —NH—, and (c) one or two repeating units selected from the group consisting of: where A is carbon or nitrogen, and X is hydrogen or halogen; and a second compound consisting of an aromatic moiety.
    Type: Application
    Filed: April 8, 2014
    Publication date: August 7, 2014
    Applicant: Electronics and Telecommunications Research Institute
    Inventors: Seung Koo PARK, Jung Jin JU, Suntak PARK, Jong-Moo LEE, Min-su KIM, Jin Tae KIM, Joong-Seon CHOE
  • Publication number: 20140205280
    Abstract: Provided is a method of measuring signal transmission time difference of a measuring device. The measuring device according to embodiments, by measuring a skew on two optical paths through signal delays of sufficient sizes for skew measurement on the optical paths, even a skew having a minute size can be measured within a measureable range.
    Type: Application
    Filed: July 3, 2013
    Publication date: July 24, 2014
    Inventors: Joong-Seon CHOE, Chun Ju YOUN, Jong-Hoi KIM, Duk Jun KIM, Yong-Hwan KWON, Kwang-Seong CHOI, Eun Soo NAM
  • Publication number: 20140169786
    Abstract: Provided is an apparatus and method for measuring IQ imbalance, and in particular, is an apparatus and method for measuring IQ imbalance for an optical receiver. The apparatus for measuring IQ imbalance for an optical receiver includes a light generating unit generating optical and reference signals to provide the optical and reference signals to an optical receiver, a graph creating unit creating a Lissajous figure by using an in-phase (I) signal and a quadrature-phase (Q) signal output from the optical receiver in response to the optical and reference signals, and a calculating unit calculating IQ imbalance for the optical receiver with reference to the Lissajous figure.
    Type: Application
    Filed: September 16, 2013
    Publication date: June 19, 2014
    Applicant: Electronics and Telecommunications Research Institute
    Inventors: Chun Ju YOUN, Jong-Hoi KIM, Joong-Seon CHOE, Duk Jun KIM, Yong-Hwan KWON, Eun Soo NAM
  • Patent number: 8716403
    Abstract: A prepolymer prepared by condensation reaction between a first compound represented by Formula (1) below: Ar—H??(1), where Ar is composed of a crosslinkable moiety at one end, a moiety selected from the group —O—, —S—, —COO—, —CO—, —COS—, —SO2—, and —NH—, and one or two repeating units selected from the group: where A is carbon or nitrogen, and X is hydrogen or halogen; and a second compound that is an aromatic moiety.
    Type: Grant
    Filed: December 9, 2009
    Date of Patent: May 6, 2014
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Seung Koo Park, Jung Jin Ju, Suntak Park, Jong-Moo Lee, Min-Su Kim, Jin Tae Kim, Joong-Seon Choe
  • Patent number: 8693459
    Abstract: Provided is a polarization division multiplexed optical OFDM transmitter. The polarization division multiplexed optical OFDM transmitter includes a data demultiplexer, a training symbol generation unit and an optical up-converter and polarization division multiplexing unit. The data demultiplexer divides a transmission signal into a plurality of groups. The training symbol generation unit allocates a plurality of training symbols for each OFDM data which is included in the respective multiplexed groups, and allocates repetitive data in a time domain for the respective training symbols for data of 0 to periodically appear for the respective training symbols in a frequency domain. The optical up-converter and polarization division multiplexing unit performs optical frequency band conversion and polarization division multiplexing on an output of the training symbol generation unit to output a polarization division multiplexed optical OFDM signal corresponding to a plurality of polarization components.
    Type: Grant
    Filed: May 3, 2010
    Date of Patent: April 8, 2014
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Chun Ju Youn, Yong-Hwan Kwon, Jong-Hoi Kim, Joong-Seon Choe, Kwang-Seong Choi, Kyoungwoo Heo, Eun Soo Nam
  • Publication number: 20130308949
    Abstract: Provided is an optical OFDM receiver. The optical OFDM receiver receives an optical signal dependent on the nonlinearity of a transmitter. The optical OFDM receives includes an optical down converter, a nonlinearity compensator, and an OFDM demodulator. The optical down converter converts the optical signal into an electrical signal. The nonlinearity compensator filters the electrical signal, for compensating distortion which is added to the optical signal when the transmitter performs optical modulation. The OFDM demodulator demodulates the distortion-compensated electrical signal in an OFDM scheme.
    Type: Application
    Filed: July 25, 2013
    Publication date: November 21, 2013
    Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Chun Ju YOUN, Yong-Hwan KWON, Eun Soo NAM, Jong-Hoi KIM, Joong-Seon CHOE, Kwang-Seong CHOI
  • Patent number: 8521040
    Abstract: Provided is an optical OFDM receiver. The optical OFDM receiver receives an optical signal dependent on the nonlinearity of a transmitter. The optical OFDM receives includes an optical down converter, a nonlinearity compensator, and an OFDM demodulator. The optical down converter converts the optical signal into an electrical signal. The nonlinearity compensator filters the electrical signal, for compensating distortion which is added to the optical signal when the transmitter performs optical modulation. The OFDM demodulator demodulates the distortion-compensated electrical signal in an OFDM scheme.
    Type: Grant
    Filed: May 4, 2010
    Date of Patent: August 27, 2013
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Chun Ju Youn, Yong-Hwan Kwon, Eun Soo Nam, Jong-Hoi Kim, Joong-Seon Choe, Kwang-Seong Choi
  • Publication number: 20130156394
    Abstract: The inventive concept relates to an optical communication module. The optical communication module may include a metal block: an electrical device formed on the metal block; an optical device adhesive block formed on the metal block; an optical device formed on the optical device adhesive block and connected to the electrical device through a bonding interconnection; and a flat type optical waveguide formed on one side of the optical device adhesive block and optically aligned with the optical device.
    Type: Application
    Filed: September 12, 2012
    Publication date: June 20, 2013
    Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Joong-Seon CHOE, Jong-Hoi Kim, Kwang-Seong Choi, Chun Ju Youn, Duk Jun Kim, Yong-Hwan Kwon, Eun Soo Nam
  • Publication number: 20130156362
    Abstract: Provided is a core which reduces optic splice loss between discontinuous optical waveguides.
    Type: Application
    Filed: September 12, 2012
    Publication date: June 20, 2013
    Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Duk Jun KIM, Jong-Hoi Kim, Joong-Seon Choe, Chun Ju Youn, Kwang-Seong Choi, Yong-Hwan Kwon, Eun Soo Nam
  • Patent number: 8272789
    Abstract: Provided are an adapter assembly and method for compensating optical fibers for a length difference. The adapter assembly includes a first adapter, a second adapter, and a member. The first adapter is configured to be connected to at least one optical communication unit. The second adapter is configured to be connected to at least another optical communication unit and be coupled to the first adapter. The member is configured to be interposed between the first and second adapters for providing an optical signal transmission path between the optical communication units. Owing to the member, a length difference between optical fibers can be compensated for.
    Type: Grant
    Filed: May 26, 2010
    Date of Patent: September 25, 2012
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Joong-Seon Choe, Yong-Hwan Kwon, Chun Ju Youn, Jong-Hoi Kim, Kwang-Seong Choi, Eun Soo Nam
  • Patent number: 8244079
    Abstract: Provided are a light emitting device and an optical coupling module. The device includes a substrate, a light emitting part provided to the substrate, and a reflecting part provided to a lower surface of the substrate. The light emitting part includes an active pattern disposed on the substrate, an upper mirror provided to an upper portion of the active pattern, and a lower mirror provided to a lower portion of the active pattern. The light emitting part may emit light normal to the substrate, and the reflecting part may reflect the emitted light to a side surface of the substrate.
    Type: Grant
    Filed: June 11, 2009
    Date of Patent: August 14, 2012
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Jin-Tae Kim, Sun-Tak Park, Jung-Jin Ju, Seung-Koo Park, Min-Su Kim, Jong-Moo Lee, Joong-Seon Choe
  • Publication number: 20120155887
    Abstract: Disclosed are a method and an apparatus for transmitting and receiving coherent optical OFDM.
    Type: Application
    Filed: November 22, 2011
    Publication date: June 21, 2012
    Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Chun Ju YOUN, Yong-Hwan Kwon, Duk Jun Kim, Jong-Hoi Kim, Joong-Seon Choe, Kwang-Seong Choi, Eun Soo Nam
  • Publication number: 20120132792
    Abstract: An exemplary embodiment of the present disclosure provides an optical module including: an optical hybrid including a metal optical waveguide; a photo detector configured to receive light; and a platform including an optical hybrid supporting section for supporting the optical hybrid, a photo detector supporting section for supporting the photo detector, and an inclined surface configured to change a propagation direction of light emitted from the optical hybrid, and configured to combine the optical hybrid and the photo detector.
    Type: Application
    Filed: October 21, 2011
    Publication date: May 31, 2012
    Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Joong-Seon Choe, Jong-Hoi Kim, Chun Ju Youn, Duk Jun Kim, Kwang-Seong Choi, Yong-Hwan Kwon, Eun Soo Nam
  • Publication number: 20120114293
    Abstract: The present disclosure relates to a planar optical waveguide element, and more particularly, to an optical waveguide end structure for effective optical signal connection with a light source, a light receiving element, or a different type of optical waveguide element. According to an exemplary embodiment of the present disclosure, there is disclosed an optical waveguide structure, including: a planar optical waveguide including a lower clad, a waveguide core formed on the lower clad, and a clad layer formed on the waveguide core; and an optical lens formed on a surface of the clad layer. One end of the optical waveguide forms an inclined surface having a predetermined inclination angle.
    Type: Application
    Filed: September 30, 2011
    Publication date: May 10, 2012
    Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Joong-Seon Choe, Duk Jun Kim, Chun Ju Youn, Jong-Hoi Kim, Kwang-Seong Choi, Yong-Hwan Kwon, Eun Soo Nam
  • Publication number: 20110142398
    Abstract: Provided are an adapter assembly and method for compensating optical fibers for a length difference. The adapter assembly includes a first adapter, a second adapter, and a member. The first adapter is configured to be connected to at least one optical communication unit. The second adapter is configured to be connected to at least another optical communication unit and be coupled to the first adapter. The member is configured to be interposed between the first and second adapters for providing an optical signal transmission path between the optical communication units. Owing to the member, a length difference between optical fibers can be compensated for.
    Type: Application
    Filed: May 26, 2010
    Publication date: June 16, 2011
    Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Joong-Seon Choe, Yong-Hwan Kwon, Chun Ju Youn, Jong-Hoi Kim, Kwang-Seong Choi, Eun Soo Nam
  • Publication number: 20110135319
    Abstract: Provided is an optical OFDM receiver. The optical OFDM receiver receives an optical signal dependent on the nonlinearity of a transmitter. The optical OFDM receives includes an optical down converter, a nonlinearity compensator, and an OFDM demodulator. The optical down converter converts the optical signal into an electrical signal. The nonlinearity compensator filters the electrical signal, for compensating distortion which is added to the optical signal when the transmitter performs optical modulation. The OFDM demodulator demodulates the distortion-compensated electrical signal in an OFDM scheme.
    Type: Application
    Filed: May 4, 2010
    Publication date: June 9, 2011
    Applicant: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventors: Chun Ju YOUN, Yong-Hwan Kwon, Eun Soo Nam, Jong-Hoi Kim, Joong-Seon Choe, Kwang-Seong Choi