Patents by Inventor Yong-Tak Lee

Yong-Tak 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: 9397479
    Abstract: The present invention relates to a silicon DBR structure-integrated light device, and a preparation method thereof, and more specifically, to a silicon DBR structure-integrated light device or vertical cavity light emitting diode, and a preparation method thereof, enabling preparation by a small number of layers and capable of reducing process time and costs due to a large contrast in refractive index of a silicon DBR structure formed by depositing silicon in a slanted or vertical manner.
    Type: Grant
    Filed: November 30, 2012
    Date of Patent: July 19, 2016
    Assignee: GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Yong-Tak Lee, Sung Joon Jang, Young Min Song
  • Patent number: 9190545
    Abstract: An optical device is provided including an active layer having two outer barriers and a coupled quantum well between the two outer barriers. The coupled quantum well includes a first quantum well layer, a second quantum well layer, a third quantum well layer, a first coupling barrier between the first quantum well layer and the second quantum well layer, and a second coupling barrier between the second quantum well layer and the third quantum well layer. A thickness of the first quantum well layer and a thickness of the third quantum well layer are each different from a thickness of the second quantum well layer. Also, an energy level of the first quantum well layer and an energy level of the third quantum well layer are each different from an energy level of the second quantum well layer.
    Type: Grant
    Filed: May 21, 2014
    Date of Patent: November 17, 2015
    Assignees: SAMSUNG ELECTRONICS CO., LTD., GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Yong-chul Cho, Yong-tak Lee, Chang-young Park, Byung-hoon Na, Yong-hwa Park, Gun-wu Ju
  • Patent number: 9151917
    Abstract: The present invention relates to the apparatus and method for optical interconnection. The present invention provides an optical interconnection structure comprising: a substrate on which double side perforated multi-hole through a predetermined region is formed; bottom hole which is etched and tapered for optical fiber array is bigger than upper hole which is etched for the optical devices. The present invention provides the optical interconnection structure that can facilitate the optical interconnection between the active optoelectronic devices that transmit/receive the optical signals and the optical fiber array, making it possible to align easily and acutely between the optical devices and optical fiber array.
    Type: Grant
    Filed: July 12, 2013
    Date of Patent: October 6, 2015
    Assignee: YTEL PHOTONICS INC.
    Inventor: Yong Tak Lee
  • Patent number: 9123832
    Abstract: A method of fabricating nanostructure for antireflection and a method of fabricating a photo device integrated with the nanostructure for antireflection are provided. The fabrication of the nanostructure for antireflection includes coating a solution containing a combination of metal ions with organic or inorganic ions on a substrate, sintering the coated solution using an annealing process to grow nanoscale metal particles, and chemically etching the substrate using the metal particles as mask or accelerator to form a subwavelength nanostructure on the surface of the substrate, thereby manufacturing the nanostructure for antireflection without an apparatus requiring a vacuum state using a simple method for a short amount of time to minimize reflection of light at an interface between a semiconductor material and the air, and producing a photo device having good luminous efficiency and performance at low cost in large quantities by applying it to the photo device.
    Type: Grant
    Filed: November 30, 2010
    Date of Patent: September 1, 2015
    Assignee: Gwangju Institute of Science and Technology
    Inventors: Chan Il Yeo, Yong Tak Lee, Young Min Song
  • Patent number: 9082909
    Abstract: Provided is an optical device which includes an active layer which includes at least two outer barriers and at least one coupled quantum well, each of the at least one coupled quantum well is sandwiched between the at least two outer barriers. Each of the at least one coupled quantum well includes at least three quantum well layers and at least two coupling barriers interposed between the at least three quantum layers. The at least two coupling barriers have a potential energy which is higher than a ground level and is lower than energy levels of the at least two outer barriers.
    Type: Grant
    Filed: January 6, 2014
    Date of Patent: July 14, 2015
    Assignees: SAMSUNG ELECTRONICS CO., LTD., GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Yong-chul Cho, Yong-tak Lee, Chang-young Park, Byung-hoon Na, Yong-hwa Park, Gun-wu Ju, Hee-ju Chio
  • Patent number: 9051178
    Abstract: A transmissive light modulator including a first reflection layer; a first active layer, arranged on the first reflection layer and including a plurality of quantum well layers and a plurality of barrier layers; a second reflection layer arranged on the first active layer; a second active layer, arranged on the second reflection layer and including a plurality of quantum well layers and a plurality of barrier layers; and a third reflection layer arranged on the second active layer, wherein the first reflection layer and the third reflection layer are each doped with a first type dopant, and the second reflection layer is doped with a second type dopant, which is electrically opposite to the first type dopant.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: June 9, 2015
    Assignees: GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY, SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Yong-chul Cho, Yong-tak Lee, Jang-woo You, Byung-hoon Na, Yong-hwa Park, Chang-young Park, Hee-ju Chio, Gun-wu Ju
  • Publication number: 20150153628
    Abstract: An optical modulator includes: a bottom reflective layer; an active layer which is disposed on the bottom reflective layer and includes a multiple quantum well layer; and a top reflective layer which is disposed on the active layer, the top reflective layer including a first top reflective layer which is disposed on the active layer, a first cavity layer which is disposed on the first top reflective layer, a second top reflective layer which is disposed on the first cavity layer, a second cavity layer which is disposed on the second top reflective layer, and a third top reflective layer which is disposed on the second cavity layer. When a center wavelength of an incident light to be modulated is ?, the active layer and the first and second cavity layers have an optical thickness that is an integer multiple of ?/2 to provide an individual resonant cavity.
    Type: Application
    Filed: February 12, 2015
    Publication date: June 4, 2015
    Applicants: GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY, SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Yong-Chul CHO, Yong-Tak LEE, Yong-Hwa PARK, Byung-Hoon NA
  • Publication number: 20150138620
    Abstract: A transmissive image modulator for allowing image modulation over a wide bandwidth with multiple Fabry-Perot resonant modes and multiple absorption modes is provided. The transmissive image modulator includes a lower reflection layer; an active layer disposed on the lower reflection layer, including multiple quantum well layers and multiple barrier layers; an upper reflection layer disposed on the active layer; and at least one micro-cavity layer disposed in at least one of the lower and upper reflection layer. The active layer and the at least one micro-cavity layer have thicknesses of a multiple of ?/2, where ? is a resonant wavelength.
    Type: Application
    Filed: December 16, 2014
    Publication date: May 21, 2015
    Applicants: GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY, SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Yong-chul CHO, Yong-tak LEE, Byung-hoon NA, Chang-young PARK, Yong-hwa PARK, Jang-woo YOU, Hee-ju CHOI
  • Publication number: 20150131691
    Abstract: The present invention relates to a silicon DBR structure-integrated light device, and a preparation method thereof, and more specifically, to a silicon DBR structure-integrated light device or vertical cavity light emitting diode, and a preparation method thereof, enabling preparation by a small number of layers and capable of reducing process time and costs due to a large contrast in refractive index of a silicon DBR structure formed by depositing silicon in a slanted or vertical manner.
    Type: Application
    Filed: November 30, 2012
    Publication date: May 14, 2015
    Inventors: Yong-Tak Lee, Sung Joon Jang, Young Min Song
  • Publication number: 20150123077
    Abstract: An optical device is provided including an active layer having two outer barriers and a coupled quantum well between the two outer barriers. The coupled quantum well includes a first quantum well layer, a second quantum well layer, a third quantum well layer, a first coupling barrier between the first quantum well layer and the second quantum well layer, and a second coupling barrier between the second quantum well layer and the third quantum well layer. A thickness of the first quantum well layer and a thickness of the third quantum well layer are each different from a thickness of the second quantum well layer. Also, an energy level of the first quantum well layer and an energy level of the third quantum well layer are each different from an energy level of the second quantum well layer.
    Type: Application
    Filed: May 21, 2014
    Publication date: May 7, 2015
    Applicants: GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY, SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Yong-chul CHO, Yong-tak LEE, Chang-young PARK, Byung-hoon NA, Yong-hwa PARK, Gun-wu JU
  • Patent number: 8879601
    Abstract: Provided is a multi-wavelength laser diode module including a plurality of laser diodes having different consecutive light emission wavelength regions, a plurality of filters respectively corresponding to the plurality of laser diodes, and an optical waveguide path that transmits light emitted from the plurality of laser diodes to the plurality of filters and collects light reflected or transmitted by the plurality of filters to transmit the collected light to the outside.
    Type: Grant
    Filed: November 1, 2013
    Date of Patent: November 4, 2014
    Assignee: Ytel Photonics Inc.
    Inventor: Yong Tak Lee
  • Publication number: 20140191196
    Abstract: Provided is an optical device which includes an active layer which includes at least two outer barriers and at least one coupled quantum well, each of the at least one coupled quantum well is sandwiched between the at least two outer barriers. Each of the at least one coupled quantum well includes at least three quantum well layers and at least two coupling barriers interposed between the at least three quantum layers. The at least two coupling barriers have a potential energy which is higher than a ground level and is lower than energy levels of the at least two outer barriers.
    Type: Application
    Filed: January 6, 2014
    Publication date: July 10, 2014
    Applicants: GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY, SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Yong-chul CHO, Yong-tak LEE, Chang-young PARK, Byung-hoon NA, Yong-hwa PARK, Gun-wu JU, Hee-ju CHIO
  • Patent number: 8760754
    Abstract: A wavelength-tunable laser system includes an optical fiber collimator array having at least two ports, an optical amplifier connected to one port of an optical fiber, an optical coupler for coupling light incident from the optical amplifier and transmitting the coupled light to another port, a diffraction grating plate for guiding each wavelength component of light incident from the optical fiber collimator array in a different direction, and an Opto-Very Large Scale Integration (Opto-VLSI) processor.
    Type: Grant
    Filed: June 4, 2010
    Date of Patent: June 24, 2014
    Assignee: Ytel Photonics Inc.
    Inventors: Yong Tak Lee, Feng Xiao, Kamal Alameh
  • Patent number: 8647903
    Abstract: A method of fabricating an antireflective grating pattern and a method of fabricating an optical device integrated with an antireflective grating pattern are provided. The method of fabricating the antireflective grating pattern includes forming a photoresist (PR) pattern on a substrate using a hologram lithography process, forming a PR lens pattern having a predetermined radius of curvature by reflowing the PR pattern, and etching the entire surface of the substrate including the PR lens pattern to form a wedge-type or parabola-type antireflective subwavelength grating (SWG) pattern having a pointed tip on a top surface of the substrate. In this method, a fabrication process is simplified, the reflection of light caused by a difference in refractive index between the air and a semiconductor material can be minimized, and the antireflective grating pattern can be easily applied to optical devices.
    Type: Grant
    Filed: December 22, 2009
    Date of Patent: February 11, 2014
    Assignee: Gwangju Institute of Science and Technology
    Inventors: Yong Tak Lee, Young Min Song
  • Publication number: 20130342894
    Abstract: The present invention relates to a wavelength conversion laser system and provides a wavelength conversion laser system including a semiconductor optical amplifier, an optical condenser that condenses light emitted from the optical amplifier, a diffraction grating plate that induces wavelength components of the light having passed through the optical condenser in different directions, and an optical very large scale integration (VLSI) processor.
    Type: Application
    Filed: August 23, 2013
    Publication date: December 26, 2013
    Applicant: Ytel Photonics Inc.
    Inventor: Yong Tak Lee
  • Publication number: 20130336611
    Abstract: An optical device includes a first waveguide extended in one direction. A second waveguide is positioned at a side of the first waveguide. The second waveguide includes the first conductive semiconductor layer, the second conductive semiconductor layer, and the undoped semiconductor layer positioned between the first conductive semiconductor layer and the second conductive semiconductor layer, wherein the undoped semiconductor layer has a refractive index larger than those of the first conductive semiconductor layer and the second conductive semiconductor layer. First and second electrodes are connected to the first conductive semiconductor layer and the second conductive semiconductor layer of the second waveguide, respectively.
    Type: Application
    Filed: June 17, 2013
    Publication date: December 19, 2013
    Inventors: YONG-TAK LEE, Sooraj Ravindran, Chan IL Yeo
  • Publication number: 20130301982
    Abstract: The present invention relates to the apparatus and method for optical interconnection. The present invention provides an optical interconnection structure comprising: a substrate on which double side perforated multi-hole through a predetermined region is formed; bottom hole which is etched and tapered for optical fiber array is bigger than upper hole which is etched for the optical devices. The present invention provides the optical interconnection structure that can facilitate the optical interconnection between the active optoelectronic devices that transmit/receive the optical signals and the optical fiber array, making it possible to align easily and acutely between the optical devices and optical fiber array.
    Type: Application
    Filed: July 12, 2013
    Publication date: November 14, 2013
    Inventor: Yong Tak Lee
  • Patent number: 8492863
    Abstract: Optical modulator having wide bandwidth based on Fabry-Perot resonant reflection is disclosed. The optical modulator includes: a bottom Distributed Bragg Reflector (DBR) layer; a top DBR layer including at least one layer, and a modified layer; and an active layer disposed between bottom and top DBR layers, wherein the at least one layer includes at least one pair of a first refractive index layer having a first refractive index and a second refractive index layer having a second refractive index, the modified layer includes at least one pair of a third refractive index layer having a third refractive index and a fourth refractive index layer having a fourth refractive index, the third and the fourth refractive indexes being different, and at least one of the third and the fourth refractive index layers has a second optical thickness that is not ?/4 or that is not an odd multiple thereof.
    Type: Grant
    Filed: November 2, 2010
    Date of Patent: July 23, 2013
    Assignees: Samsung Electronics Co., Ltd., Gwangju Institute of Science and Technology
    Inventors: Yong-chul Cho, Yong-tak Lee, Yong-hwa Park, Byung-hoon Na, Kwang-mo Park, Chang-soo Park
  • Publication number: 20130175500
    Abstract: A transmissive light modulator including a first reflection layer; a first active layer, arranged on the first reflection layer and including a plurality of quantum well layers and a plurality of barrier layers; a second reflection layer arranged on the first active layer; a second active layer, arranged on the second reflection layer and including a plurality of quantum well layers and a plurality of barrier layers; and a third reflection layer arranged on the second active layer, wherein the first reflection layer and the third reflection layer are each doped with a first type dopant, and the second reflection layer is doped with a second type dopant, which is electrically opposite to the first type dopant.
    Type: Application
    Filed: September 14, 2012
    Publication date: July 11, 2013
    Applicants: GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY, SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Yong-chul CHO, Yong-tak LEE, Jang-woo YOU, Byung-hoon NA, Yong-hwa PARK, Chang-young PARK, Hee-ju CHIO, Gun-wu JU
  • Publication number: 20130128362
    Abstract: A micro/nano combined structure, a manufacturing method of a micro/nano combined structure, and a manufacturing method of an optical device having a micro/nano combined structure integrated therewith, the method comprising: forming a micro structure on a substrate; depositing a metal thin film on the substrate on which the micro structure is formed; heat treating and transforming the metal thin film into metal particles; and using the metal particles as a mask to form a non-reflective nanostructure having a frequency below that of light wavelengths and a sharp wedge-shaped end, on the top surface of the substrate on which the micro structure is formed, and etching the front surface of the substrate on which the micro structure is formed. The manufacturing process is simple, light reflectivity that occurs wherein a difference in refractive indices of air and semiconductor material can be minimized, and is easily applied to the optical device field.
    Type: Application
    Filed: July 29, 2011
    Publication date: May 23, 2013
    Applicant: GWANGJU INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Young Min Song, Yong Tak Lee