Patents by Inventor O Ok Park

O Ok Park 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: 6645403
    Abstract: Disclosed herein is a multiphase electrorheological fluid having an improved yield stress and stability. The multiphase electrorheological fluid comprises a first liquid phase component as a continuous oil phase; particles dispersed in the continuous oil phase; and a second liquid phase component which consists of emulsion liquid droplets and is dispersed in the continuous oil phase while being immiscible with the continuous oil phase. The dispersed liquid droplets have higher electrical conductivity and dielectric constant than those of the continuous oil phase.
    Type: Grant
    Filed: August 22, 2000
    Date of Patent: November 11, 2003
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: O Ok Park, Byung Doo Chin
  • Patent number: 6593688
    Abstract: The present invention relates to an organic luminescent material/clay nanocomposite with improved luminescent efficiency and stability, which is prepared by blending an organic luminescent material with a nanoclay, and an electroluminescent device employing the same. The electroluminescent device of the invention comprises: a transparent substrate; a semitransparent electrode deposited on the transparent substrate; a clay nanocomposite emissive layer spin-coated with an organic EL material/clay nanocomposite, positioned on the semitransparent electrode; and, a metal electrode deposited on the clay nanocomposite emissive layer. Since the electroluminescent device of the invention provides improved luminescent efficiency and stability, it can be practically applied to the development of organic semi-conductor.
    Type: Grant
    Filed: November 27, 2001
    Date of Patent: July 15, 2003
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: O-Ok Park, Tae-Woo Lee
  • Patent number: 6538263
    Abstract: The present invention provides ionomer-type emissive polymer whose heat-stability is improved by the formation of ionic cross-link, and electroluminescent device employing the same as an emissive layer. The ionomer-type emissive polymer is characterized by an ionomeric conformation, which has a backbone in a conjugate, non-conjugate or conjugate/non-conjugate multi-block conformation with or without a side chain in a conjugate or non-conjugate conformation, and 0.1 to 15% (mol/mol) of ions bound to the backbone or side chain of the emissive polymer with or without linker. The electroluminescent diode employing ionomer-type emissive polymer can be applied to the preparation of long-life and electricity-saving electroluminescent display device since it can luminesce at low voltage due to its ionomeric conformation and have higher heat-stability than the conventional ones.
    Type: Grant
    Filed: June 18, 2001
    Date of Patent: March 25, 2003
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: O-Ok Park, Tae-Woo Lee
  • Publication number: 20030025101
    Abstract: The present invention provides a magnetorheological fluid in which magnetic particles coated with a hydrophilic surfactant are dispersed in a water in oil emulsion, and a process for preparing the same. The magnetorheological fluid of the present invention is prepared by adding water to oil dissolved with emulsifier, stirring it to give a mobile phase of water in oil emulsion, and dispersing magnetic particles coated with a hydrophilic surfactant in the water in oil emulsion. The invented magnetorheological fluid is improved in terms of stability through the interaction between surfactant of the magnetic particle surface and water molecule, which makes possible its practical application in the development of variable devices employing the magnetorheological fluid.
    Type: Application
    Filed: January 10, 2002
    Publication date: February 6, 2003
    Inventors: O-Ok Park, Jong-Hyeok Park, Byung-Doo Chin
  • Patent number: 6429263
    Abstract: A method for fabricating a preform for a plastic optical fiber, having continuous refractive index profile in a radial direction, comprising a firs step of introducing a mixture consisting of at least two substances, each having a different density and refractive index relative to each other, to a cylindrical reactor and polymerizing the mixture in a centrifugal field generated by rotating the reactor; a second step of compensating for a void formed by volume shrinkage from the polymerization in the first step with a mixture consisting of at least two substances, each having a different density and refractive index relative to each other, and polymerizing the mixture in a centrifugal field generated by rotating the reactor, and a third step of repeating the second step until there is no void after polymerization
    Type: Grant
    Filed: January 10, 2001
    Date of Patent: August 6, 2002
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jin Teak Hwang, O Ok Park, Sang Hyuk Im, Duck Jong Suh, Han Sol Cho
  • Publication number: 20020041151
    Abstract: The present invention relates to an organic luminescent material/clay nanocomposite with improved luminescent efficiency and stability, which is prepared by blending an organic luminescent material with a nanoclay, and an electroluminescent device employing the same. The electroluminescent device of the invention comprises: a transparent substrate; a semitransparent electrode deposited on the transparent substrate; a clay nanocomposite emissive layer spin-coated with an organic EL material/clay nanocomposite, positioned on the semitransparent electrode; and, a metal electrode deposited on the clay nanocomposite emissive layer. Since the electroluminescent device of the invention provides improved luminescent efficiency and stability, it can be practically applied to the development of organic semi-conductor.
    Type: Application
    Filed: November 27, 2001
    Publication date: April 11, 2002
    Inventors: O-Ok Park, Tae-Woo Lee
  • Publication number: 20020037432
    Abstract: The present invention relates to electroluminescent devices employing single-ion conductors as the materials for an electron- or hole-injecting layer. Preferred electroluminescent devices employ an electron- or hole-injecting layer made of single-ion conductors in a conventional electroluminescent device which comprises: a transparent substrate; a semitransparent electrode deposited on the transparent substrate; a hole-injecting layer positioned on the semitransparent electrode; an electroluminescent layer made of organic luminescent material, positioned on the hole-injecting layer; an electron-injecting layer positioned on the electroluminescent layer; and, a metal electrode deposited on the electron-injecting layer. The electroluminescent devices of the invention have excellent electroluminescent efficiency and low turn-on voltage, which make possible their application to the development of high efficiency electroluminescent devices.
    Type: Application
    Filed: November 27, 2001
    Publication date: March 28, 2002
    Inventors: O-Ok Park, Tae-Woo Lee
  • Publication number: 20010026875
    Abstract: A method for fabricating a preform for a plastic optical fiber, having continuous refractive index profile in a radial direction, comprising a firs step of introducing a mixture consisting of at least two substances, each having a different density and refractive index relative to each other, to a cylindrical reactor and polymerizing the mixture in a centrifugal field generated by rotating the reactor; a second step of compensating for a void formed by volume shrinkage from the polymerization in the first step with a mixture consisting of at least two substances, each having a different density and refractive index relative to each other, and polymerizing the mixture in a centrifugal field generated by rotating the reactor, and a third step of repeating the second step until there is no void after polymerization
    Type: Application
    Filed: January 10, 2001
    Publication date: October 4, 2001
    Inventors: Jin Teak Hwang, O Ok Park, Sang Hyuk Im, Duck Jong Suh, Han Sol Cho