Patents by Inventor Bruce Chai

Bruce Chai 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: 9658344
    Abstract: A radiation detector, such as for a PET scanner, may include an array of scintillator crystals, with each scintillator crystal having a polished end, a roughened end opposite the polished end, and polished sides extending between the polished end and the roughened end. The detector may also include a specular reflector layer between adjacent polished sides of adjacent ones of the array of scintillator crystals, and a diffusive reflector layer adjacent the roughened ends of the array of scintillator crystals. The detector may further include at least one photodetector adjacent the polished ends of the array of scintillator crystals.
    Type: Grant
    Filed: November 4, 2015
    Date of Patent: May 23, 2017
    Assignee: CRYSTAL PHOTONICS, INCORPORATED
    Inventors: Bruce Chai, Xiao-mei Pan, Bao-hui Zhou
  • Publication number: 20170123080
    Abstract: A radiation detector, such as for a PET scanner, may include an array of scintillator crystals, with each scintillator crystal having a polished end, a roughened end opposite the polished end, and polished sides extending between the polished end and the roughened end. The detector may also include a specular reflector layer between adjacent polished sides of adjacent ones of the array of scintillator crystals, and a diffusive reflector layer adjacent the roughened ends of the array of scintillator crystals. The detector may further include at least one photodetector adjacent the polished ends of the array of scintillator crystals.
    Type: Application
    Filed: November 4, 2015
    Publication date: May 4, 2017
    Inventors: Bruce CHAI, Xiao-mei PAN, Bao-hui ZHOU
  • Patent number: 7972438
    Abstract: This invention is related to material for use as an ultraviolet (UV) optical element and particularly for use as a 193 nm immersion lens element. The material for use as a UV optical element includes a Lithium Magnesium Aluminate (LMAO) body. The specific compound for this application is the disordered lithium magnesium spinel, having the general composition of LixMg2(1?x)Al4+xO8 where x=0 to 1 as the high-index UV transparent material for immersion lithography. The LMAO body may include a disordered spinel, such as, for example, a single crystal that may be cubic in symmetry, optically isotropic, and having cation disorder within the structure to reduce the intrinsic birefringence (IBR). The LMAO body has certain desired material properties and may be readily made in relatively large sizes suitable for use as the UV optical element for photolithography.
    Type: Grant
    Filed: August 29, 2007
    Date of Patent: July 5, 2011
    Assignee: Crystal Photonics, Incorporated
    Inventors: Yi-Ting Fei, Shen Jen, Bruce Chai
  • Publication number: 20080055715
    Abstract: This invention is related to material for use as an ultraviolet (UV) optical element and particularly for use as a 193 nm immersion lens element. The material for use as a UV optical element includes a Lithium Magnesium Aluminate (LMAO) body. The specific compound for this application is the disordered lithium magnesium spinel, having the general composition of LixMg2(1-x)Al4+xO8 where x=0 to 1 as the high-index UV transparent material for immersion lithography. The LMAO body may include a disordered spinel, such as, for example, a single crystal that may be cubic in symmetry, optically isotropic, and having cation disorder within the structure to reduce the intrinsic birefringence (IBR). The LMAO body has certain desired material properties and may be readily made in relatively large sizes suitable for use as the UV optical element for photolithography.
    Type: Application
    Filed: August 29, 2007
    Publication date: March 6, 2008
    Applicant: Crystal Photonics, Incorporated
    Inventors: Yi-Ting Fei, Shen Jen, Bruce Chai
  • Patent number: 7166845
    Abstract: A method for enhancing the light yield of a single crystal of cerium doped lutetium yttrium orthosilicate (LYSO) in response to irradiation with high energy radiation includes diffusing oxygen into the crystal by heating the crystal for a period of time in an ambient containing oxygen. This process of thermal oxygenation of the crystal effectively supplies oxygen to fill at least some of the oxygen vacancies in the body of monocrystalline LYSO. A scintillation detector comprises a monocrystalline body of LYSO enhanced by oxygen diffusion into the crystal.
    Type: Grant
    Filed: January 9, 2004
    Date of Patent: January 23, 2007
    Assignee: Crystal Photonics, Incorporated
    Inventor: Bruce Chai
  • Patent number: 7151261
    Abstract: A method for enhancing the light yield of a single crystal of cerium doped lutetium orthosilicate (LSO) in response to irradiation with high energy radiation includes diffusing oxygen into the crystal by heating the crystal for a period of time in an ambient containing oxygen. This process of thermal oxygenation of the crystal effectively supplies oxygen to fill at least some of the oxygen vacancies in the body of monocrystalline LSO. A scintillation detector comprises a monocrystalline body of LSO enhanced by oxygen diffusion into the crystal.
    Type: Grant
    Filed: January 9, 2004
    Date of Patent: December 19, 2006
    Assignee: Crystal Photonics, Incorporated
    Inventor: Bruce Chai
  • Publication number: 20060011845
    Abstract: A method for enhancing the light yield of a doped scintillation crystal may include a reducing step if the crystal includes a dopant, such as cerium in a first oxidation state, such as the 4+ state. The scintillation crystal may include a rare earth silicate. The reducing may include heating in an oxygen-free ambient. The reducing may be used after an oxygen vacancy filling step that causes at least some of the dopant to increase in its oxidation state.
    Type: Application
    Filed: September 19, 2005
    Publication date: January 19, 2006
    Applicant: Crystal Photonics, Incorporated
    Inventors: Bruce Chai, David Chai, Randall Lux
  • Publication number: 20050253072
    Abstract: A method for enhancing the light yield of a single crystal of cerium doped lutetium orthosilicate (LSO) in response to irradiation with high energy radiation includes diffusing oxygen into the crystal by heating the crystal for a period of time in an ambient containing oxygen. This process of thermal oxygenation of the crystal effectively supplies oxygen to fill at least some of the oxygen vacancies in the body of monocrystalline LSO. A scintillation detector comprises a monocrystalline body of LSO enhanced by oxygen diffusion into the crystal.
    Type: Application
    Filed: January 9, 2004
    Publication date: November 17, 2005
    Inventor: Bruce Chai
  • Patent number: 6218280
    Abstract: The subject invention pertains to a method and device for producing large area single crystalline III-V nitride compound semiconductor substrates with a composition AlxInyGal-x-y N (where O≦x≦1, 0≦y≦1, and 0≦x+y≦1). In a specific embodiment, GaN substrates, with low dislocation densities (˜107 cm2) can be produced. These crystalline III-V substrates can be used to fabricate lasers and transistors. Large area free standing single crystals of III-V compounds, for example GaN, can be produced in accordance with the subject invention. By utilizing the rapid growth rates afforded by hydride vapor phase epitaxy (HVPE) and growing on lattice matching orthorhombic structure oxide substrates, good quality III-V crystals can be grown. Examples of oxide substrates include LiGaO2, LiAlO2, MgAlScO4, Al2MgO4, and LiNdO2. The subject invention relates to a method and apparatus, for the deposition of III-V compounds, which can alternate between MOVPE and HVPE, combining the advantages of both.
    Type: Grant
    Filed: June 18, 1999
    Date of Patent: April 17, 2001
    Assignees: University of Florida, University of Central Florida
    Inventors: Olga Kryliouk, Tim Anderson, Bruce Chai