Patents by Inventor S. K. Lee

S. K. 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: 7343002
    Abstract: A bearing assembly suitable for use in conjunction with x-ray device having a rotating target anode and electron source disposed in an evacuated enclosure. The bearing assembly includes a shaft having a rotor hub to which the anode is mounted. The shaft cooperates with front and rear bearing rings to define front and rear races, and a spacer facilitates positioning of the bearing rings. Front and rear ball sets are confined in the front and rear races, respectively. A bearing housing receives the bearing rings, spacer, front and rear ball sets, and part of the shaft. Finally, a magnet is disposed near the front bearing ring to prevent escape of foreign matter from the bearings and to prevent ingress of foreign matter to the bearings. Consequently, the magnet serves to extend the life of the bearings and to prevent foreign matter related arcing of the target anode and electron source.
    Type: Grant
    Filed: February 5, 2003
    Date of Patent: March 11, 2008
    Assignee: Varian Medical Systems Technologies, Inc.
    Inventors: David S. K. Lee, John E. Postman
  • Patent number: 7127034
    Abstract: A composite stator is disclosed for use with rotationally driven apparatus, particularly high voltage x-ray tubes. The composite stator generally comprises a core, a plurality of motor windings, and a retaining band. The core is comprised of two or more core sections having slots defined therein for receiving the motor windings. The motor windings are wound through and between the slots of the core sections, after which the core sections are joined together to form the core. The core sections are maintained in an assembled configuration by the retaining band. The motor windings are interconnected to comprise the electromagnetic pole pairs of the composite stator, thereby allowing the stator to induce the rotation of the rotor assembly of the high voltage x-ray tube.
    Type: Grant
    Filed: February 5, 2003
    Date of Patent: October 24, 2006
    Assignee: Varian Medical Systems Technologies, Inc.
    Inventors: David S. K. Lee, Paul D. Moore, John E. Postman
  • Patent number: 6749101
    Abstract: A method for manufacturing x-ray tube parts wherein metallic pieces are explosively bonded together to establish a high strength, stable union between them. The x-ray tube parts may then be milled from the bonded metallic pieces. The explosion bonding process creates only discrete intermetallic components in the joint region instead of a continuous, weakening intermetallic layer common in brazed joints. An explosion bond joint is characterized by a wavelike interface, thereby increasing surface area over which the components are bonded and further increasing bond integrity. Rotor sleeves and other tube components may be manufactured using this method.
    Type: Grant
    Filed: August 29, 2003
    Date of Patent: June 15, 2004
    Assignee: Varian Medical Systems, Inc.
    Inventors: David S. K. Lee, Richard R. Sano
  • Patent number: 6740549
    Abstract: Gate stacks with sidewall spacers having improved profiles to suppress or eliminate void formation between the gate stacks during gap-filling is disclosed, along with a method of forming the gate structures over a semiconductor substrate. A gate dielectric layer is formed on a semiconductor substrate. Then, a gate stack 24 having a sidewall is formed over the gate dielectric layer. The gate stack 24 comprises a conductive layer 28 and a capping nitride layer 30 overlying the conductive layer 28. A liner 32 is selectively deposited over the gate stack 24 such that the liner 32 is deposited on the capping nitride layer 30 at a rate lower than the rate of deposition on the conductive layer 28. Thus, the liner 32 is substantially thinner on the capping nitride layer 30 than on the conductive layer 28. A nitride spacer is formed over 34 the liner 32. A PMD layer is formed over the resultant structure, filling the gaps between adjacent gate stacks and substantially free of voids.
    Type: Grant
    Filed: August 10, 2001
    Date of Patent: May 25, 2004
    Assignee: Integrated Device Technology, Inc.
    Inventors: Chih-Hsiang Chen, Guo-Qiang Lo, S. K. Lee
  • Patent number: 6612478
    Abstract: A method for manufacturing x-ray tube parts, wherein metallic pieces are explosively bonded together to establish a high strength, stable union between them. The x-ray tube parts may then be milled from the bonded metallic pieces. The explosion bonding process creates only discrete intermetallic components in the joint region instead of a continuous, weakening intermetallic layer common in brazed joints. An explosion bond joint is characterized by a wavelike interface, thereby increasing surface area over which the components are bonded and further increasing bond integrity. Stems, rotor hubs, rotor sleeves, anodes, and other tube components may be manufactured using this method.
    Type: Grant
    Filed: May 14, 2001
    Date of Patent: September 2, 2003
    Assignee: Varian Medical Systems, Inc.
    Inventors: David S. K. Lee, Richard R. Sano
  • Patent number: 6576976
    Abstract: A first insulating layer (12) overlying semiconductor substrate (10) has a plurality of conductive paths (14, 16) disposed thereon. Each of the plurality of conductive paths has at least a major portion thereof overlied with a second insulating layer (20). A third insulating layer (26), having air gap ports (28) formed therein, overlies adjacent conductive paths and extends from one to another such that an air gap (34) is formed. A passivation layer (30) overlies third insulating layer and seals the plurality of air gaps ports to form an insulation structure (40) for a semiconductor integrated circuit, and method thereof.
    Type: Grant
    Filed: February 22, 2001
    Date of Patent: June 10, 2003
    Assignee: Integrated Device Technology, Inc.
    Inventors: Chuen-Der Lien, S. K. Lee
  • Publication number: 20020168051
    Abstract: A method for manufacturing x-ray tube parts is disclosed wherein metallic pieces are explosively bonded together to establish a high strength, stable union between them. The x-ray tube parts may then be milled from the bonded metallic pieces. The explosion bonding process creates only discrete intermetallic components in the joint region instead of a continuous, weakening intermetallic layer common in brazed joints. An explosion bond joint is characterized by a wavelike interface, thereby increasing surface area over which the components are bonded and further increasing bond integrity. Stems, rotor hubs, rotor sleeves, anodes, and other tube components may be manufactured using this method.
    Type: Application
    Filed: May 14, 2001
    Publication date: November 14, 2002
    Applicant: Varian Medical Systems, Inc
    Inventors: David S.K. Lee, Richard R. Sano
  • Patent number: 6351681
    Abstract: A method and apparatus for a multi-chip module that is testable and reconfigurable based on testing results is accomplished by a multi-chip module that includes a first circuit disposed on a first chip substrate, a second circuit disposed on second chip substrate, and an interconnecting substrate operably coupled to the first chip substrate and the second chip substrate. The interconnecting substrate connects the first circuit to the second circuit. The interconnecting substrate includes external connectors for accessing signals within the multi-chip module, which allow the multi-chip module to be fully tested. This testing may include isolating the first circuit and/or the second circuit by disabling other circuits in order to allow each of the circuits to be exercised without interference from other circuits. After testing the multi-chip module, configuration circuitry included on the multi-chip module may be used to reconfigure the multi-chip module based on results of the testing.
    Type: Grant
    Filed: November 23, 1998
    Date of Patent: February 26, 2002
    Assignee: ATI International Srl
    Inventors: David Chih, Lee K. Lau, Keith S. K. Lee
  • Publication number: 20010040267
    Abstract: A first insulating layer (12) overlying semiconductor substrate (10) has a plurality of conductive paths (14, 16) disposed thereon. Each of the plurality of conductive paths has at least a major portion thereof overlied with a second insulating layer (20). A third insulating layer (26), having air gap ports (28) formed therein, overlies adjacent conductive paths and extends from one to another such that an air gap (34) is formed. A passivation layer (30) overlies third insulating layer and seals the plurality of air gaps ports to form an insulation structure (40) for a semiconductor integrated circuit, and method thereof.
    Type: Application
    Filed: February 23, 2001
    Publication date: November 15, 2001
    Inventors: Chuen-Der Lien, S. K. Lee
  • Patent number: 6096502
    Abstract: A UL9 substrate for detecting helicase activity in a UL9 protein is provided. In one embodiment, the substrate includes a first strand including a herpes replication origin sequence and a first single stranded tail; and a second strand including a sequence complementary to the herpes replication origin sequence. In one variation, the first single stranded tail is 3' relative to the herpes replication origin sequence. The second strand may optionally further include a single stranded tail. The single stranded tail on the second strand may be 3' or 5' relative to the sequence complementary to the herpes replication origin sequence. In another variation, the first single stranded tail is 5' relative to the herpes replication origin sequence. The second strand may optionally further include a single stranded tail. The single stranded tail on the second strand may be 3' or 5' relative to the sequence complementary to the herpes replication origin sequence.
    Type: Grant
    Filed: March 30, 1998
    Date of Patent: August 1, 2000
    Assignee: Sam S.-K. Lee
    Inventor: Sam S.-K. Lee
  • Patent number: 5449658
    Abstract: The growth of algae, fungi and pathogenic organisms in commercial and recreational waters, such as cooling towers, swimming pools and spas, may be controlled by adding to the water a primary sanitizing agent, preferably poly(hexamethylene biguanide) ("PHMB"), and a potentiating adjuvant comprising a calcium ion-chelating agent, preferably ethylenediamine tetraacetic acid ("EDTA"), in amounts such that the adjuvant renders the composition algicidal and fungicidal in water. The water may be further treated with a peroxy salt as a backup agent, preferably sodium perborate, or the calcium ion-chelating agent and peroxy salt may be combined as a shock treatment to water being treated with the primary sanitizing agent.
    Type: Grant
    Filed: December 7, 1993
    Date of Patent: September 12, 1995
    Assignee: Zeneca, Inc.
    Inventors: Michael J. Unhoch, Peter S. K. Lee, David G. Chasin
  • Patent number: 5369031
    Abstract: The present invention provides an economical and efficient method for the elimination and biodegradation of soil and groundwater containing polar organic solvents, especially acetone. The bioremediation methods of the present invention comprise contacting the bacteria Xanthomonas maltophilia or Bacillus thuringiensis with the contaminated medium under appropriate conditions. In addition, the present invention provides for a composition of matter useful in the bioremediation of a medium, e.g., groundwater or soil contaminated with polar organic compounds, such as acetone.
    Type: Grant
    Filed: July 21, 1992
    Date of Patent: November 29, 1994
    Assignee: University of Houston
    Inventors: Brian S. Middleditch, Peter S. K. Lee
  • Patent number: 5309221
    Abstract: Methods for measuring the diameters of transparent filaments with high precision, e.g., RMS standard deviations of less than 0.02 microns, are provided. The methods involve determining the average spatial frequency .omega. of the far-field interference pattern produced by illuminating the filament with a beam of laser light. The average spatial frequency is determined by performing a fast Fourier transform (FFT) on the interference data to obtain a coarse estimate for the average and then performing a set of discrete sequence Fourier transforms (DSFTs) in the region of the coarse estimate to obtain the desired high precision estimate of the average. Efficient on-line processing procedures are provided so that real time measurements can be performed on, for example, a moving optical waveguide fiber, at rates of 500 measurements/second and above.
    Type: Grant
    Filed: December 31, 1991
    Date of Patent: May 3, 1994
    Assignee: Corning Incorporated
    Inventors: Frederic P. Fischer, Patrick S. K. Lee, Raymond C. Logue, Thomas W. Parks
  • Patent number: 5231570
    Abstract: A credit card status verification system is disclosed in which the status of very large numbers of credit cards is contained and accessed from a compact storage media, such as a CD-ROM disk, at a remote location, thereby eliminating the necessity of obtaining the status information from a centrally located facility via a communication link. A data mapping algorithm is employed to map credit card numbers to status containing locations within memory without requiring large amounts of memory space for addressing. A multiple level screening process is employed for checking the validity of a credit card number and the credit status of a credit card which is both quick and economical.
    Type: Grant
    Filed: December 11, 1990
    Date of Patent: July 27, 1993
    Inventor: Gerritt S. K. Lee
  • Patent number: 5210858
    Abstract: A clocking control circuit for a computer system and method for receiving a microprocessor clock signal which drives a microprocessor and for supplying a support clock signal having a lower frequency. The support clock frequency drives support interface circuitry such as a peripheral controller, a CPU/memory controller, and a bus bridge interface, and thus causes the support interface circuitry to operate at a lower frequency than the microprocessor. The clocking control circuit ensures synchronization between the support clocking signal and the microprocessor clocking signal. The transmission of control signals between the microprocessor and support interface circuitry is controlled to ensure proper communications between the microprocessor and support circuitry.
    Type: Grant
    Filed: October 17, 1989
    Date of Patent: May 11, 1993
    Inventors: Jan E. B. Jensen, Keith S. K. Lee, J. David Mulvenna, Keith B. Riley
  • Patent number: 4899381
    Abstract: A pair of interface devices, mounted externally to a pair of residential telephones, can place a temporary hold on the associated telephone line circuit. Each interface device interconnects a standard residential telephone with an associated telephone line circuit. In a two telephone arrangement to place the telephone circuit in a hold condition, the user throws a switch mounted on the interface device, and hangs up the handset (goes on hook). The switch places two indicator lamps across the two-wire line circuit to simulate an off-hook condition. To remove the hold condition, the user merely throws the same switch or the switch associated with one of the other phones in the residence. There is no need to return to the original phone first used to establish the hold.
    Type: Grant
    Filed: April 7, 1989
    Date of Patent: February 6, 1990
    Assignee: GTE Hawaiian Telephone Company Incorporated
    Inventor: Gerritt S. K. Lee
  • Patent number: 4319288
    Abstract: A tapped delay line (38) terminated with its characteristic impedance at both ends is connected to receive a differential input signal in intermediate taps (27, 29) of a delay line. Delay line taps (25, 27, 29, 31), as well as ends (21, 23) are connected symmetrically to two pair of summing networks (59, 61 and 83, 85) where voltage signal components having different delays from the input signal are linearly combined. One pair of summing networks (59, 61) produces a balanced differential output signal which is an amplitude equalized and differentiated version of the input signal, while the other pair of summing networks (83, 85) produces another balanced differential output signal which is a different amplitude equalized version of the input signal. Each version is needed in one of the channels of a dual channel signal detector for detecting the peaks of the variable amplitude input signal.
    Type: Grant
    Filed: April 9, 1980
    Date of Patent: March 9, 1982
    Assignee: Sperry Corporation
    Inventor: Patrick S. K. Lee