Patents by Inventor Shih-Fu Lee

Shih-Fu 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: 7009391
    Abstract: The present invention provides a method for detecting missing servo patterns on printed recording media. In general, the method first comprises the step of generating a map of anticipated servo burst patterns for a magnetic medium. The magnetic medium is typically a magnetic storage disc. Next, the magnetic medium is placed onto a disc reading assembly. Using the disc reading assembly, individual servo bursts on the magnetic medium are identified. In one embodiment, signals from the magnetic medium are processed through a frequency down conversion process, coupled with band pass filtering and rms-to-DC conversion. This enables higher throughput of signal processing. A map of identified servo bursts on the magnetic medium can then be generated. The map of identified servo bursts is then compared with the map of anticipated servo burst patterns. In this way, missing servo bursts can be detected.
    Type: Grant
    Filed: October 15, 2003
    Date of Patent: March 7, 2006
    Assignee: Seagate Technology LLC
    Inventors: Shih-Fu Lee, David Kuo, Jason L. Pressesky
  • Patent number: 6979524
    Abstract: A method of forming a magnetic transition pattern in a longitudinal magnetic recording medium, comprising steps of: (a) providing a magnetic recording medium including a layer of a magnetic material having a surface comprised of a plurality of longitudinally extending magnetic domains; (b) contacting the surface of the layer of magnetic material with a topographically patterned imprinting surface of a stamper/imprinter formed of at least one high saturation magnetization, high permeability magnetic material; and (c) applying a unidirectional magnetic field perpendicular to the imprinting surface of the stamper/imprinter, the perpendicular magnetic field creating a longitudinal magnetic field component of sufficient strength to effect selective alignment of the magnetic domains of those portions of the layer of magnetic material which face the depressions of the imprinting surface while retaining the alignment of the magnetic domains of those portions of the layer of magnetic material which face the project
    Type: Grant
    Filed: April 18, 2003
    Date of Patent: December 27, 2005
    Assignee: Seagate Technology LLC
    Inventors: Koichi Wago, Shih-Fu Lee, Li-Ping Wang, Joseph Leigh
  • Patent number: 6968731
    Abstract: A system and a method for measuring micro-waviness of a magnetic recording disk using a high-speed glide test are disclosed. The HSG test is a viable production-level test methodology for high performance media that require well-controlled and low micro-waviness.
    Type: Grant
    Filed: July 29, 2003
    Date of Patent: November 29, 2005
    Assignee: Seagate Technology
    Inventors: Yong Hu, Eric Kenneth Dahlin, Shih-Fu Lee, Hamid F. Ghazvini, Elias Ted Johnson, Jr.
  • Patent number: 6940667
    Abstract: A plurality of redundant sets of servo data are recorded on a magnetic hard disk. The set meeting a predetermine criteria is employed when the hard disk is assembled into a hard disk drive. The determination of which set has the criteria may be conducted by the disk drive itself. The criteria may include a determination the set of servo data having meeting a minimum quality criteria or the fewest errors. The criteria may include a selection of a set of servo data having a specific pattern where the prerecorded sets may comprise a differing servo patterns that may be used by disk drives requiring specific servo patterns. The servo data are printed onto the hard disk by means of a stamper or mask having all the sets of servo data.
    Type: Grant
    Filed: January 10, 2003
    Date of Patent: September 6, 2005
    Assignee: Seagate Technology LLC
    Inventors: David S. Kuo, Shih-Fu Lee, Neil N. Deeman
  • Publication number: 20050083047
    Abstract: The present invention provides a method for detecting missing servo patterns on printed recording media. In general, the method first comprises the step of generating a map of anticipated servo burst patterns for a magnetic medium. The magnetic medium is typically a magnetic storage disc. Next, the magnetic medium is placed onto a disc reading assembly. Using the disc reading assembly, individual servo bursts on the magnetic medium are identified. In one embodiment, signals from the magnetic medium are processed through a frequency down conversion process, coupled with band pass filtering and rms-to-DC conversion. This enables higher throughput of signal processing. A map of identified servo bursts on the magnetic medium can then be generated. The map of identified servo bursts is then compared with the map of anticipated servo burst patterns. In this way, missing servo bursts can be detected.
    Type: Application
    Filed: October 15, 2003
    Publication date: April 21, 2005
    Inventors: Shih-Fu Lee, David Kuo, Jason Pressesky
  • Publication number: 20050022586
    Abstract: A system and a method for measuring micro-waviness of a magnetic recording disk using a high-speed glide test are disclosed. The HSG test is a viable production-level test methodology for high performance media that require well-controlled and low micro-waviness.
    Type: Application
    Filed: July 29, 2003
    Publication date: February 3, 2005
    Inventors: Yong Hu, Eric Dahlin, Shih-Fu Lee, Hamid Ghazvini, Elias Johnson
  • Publication number: 20040209185
    Abstract: A method of forming a magnetic transition pattern in a longitudinal magnetic recording medium, comprising steps of:
    Type: Application
    Filed: April 18, 2003
    Publication date: October 21, 2004
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Koichi Wago, Shih-Fu Lee, Li-Ping Wang, Joseph Leigh
  • Publication number: 20040196469
    Abstract: An optical profiler for an ultra-smooth surface, such as a magnetic recording disk, provides for a normally incident beam deflection against the target surface to be profiled. A linearly polarized laser light of a first polarization is focused on the target surface in a normally incident direction. The beam is reflected back along its original path from the focal point. Optics are provided that change the polarization of the reflected beam to a second polarization. A reflected beam, with a second polarization, is directed onto a position sensitive detector for evaluation.
    Type: Application
    Filed: November 5, 2003
    Publication date: October 7, 2004
    Applicant: SEAGATE TECHNOLOGY LLC
    Inventors: Jianmin Wang, Jason L. Pressesky, Shih-Fu Lee
  • Publication number: 20040001266
    Abstract: A plurality of redundant sets of servo data are recorded on a magnetic hard disk. The set meeting a predetermine criteria is employed when the hard disk is assembled into a hard disk drive. The determination of which set has the criteria may be conducted by the disk drive itself. The criteria may include a determination the set of servo data having meeting a minimum quality criteria or the fewest errors. The criteria may include a selection of a set of servo data having a specific pattern where the prerecorded sets may comprise a differing servo patterns that may be used by disk drives requiring specific servo patterns. The servo data are printed onto the hard disk by means of a stamper or mask having all the sets of servo data.
    Type: Application
    Filed: January 10, 2003
    Publication date: January 1, 2004
    Inventors: David S. Kuo, Shih-Fu Lee, Neil N. Deeman
  • Publication number: 20030065495
    Abstract: A method and apparatus for disc drive modeling to determine head-to-media spacing subject to disc media topography, roughness and waviness, is disclosed. More particularly, an equation describing head-to-media spacing associated with roughness and waviness of a disc media surface is described. A process for simulating a head traveling over a reference disc media surface is used to implement such an equation. This simulation results in an air bearing transfer function for a spectral density, which is convolved with a power spectral density function for a disc media surface under test. Such a result may be used to predict glide avalanche for the head and the disc media under test.
    Type: Application
    Filed: November 1, 2001
    Publication date: April 3, 2003
    Inventors: Shih-Fu Lee, Yong Hu, David Kuo