Patents Assigned to Excel Precision Corporation
  • Patent number: 7375822
    Abstract: A position determining system (PDS)(100) or multiple parameters measurement system (MPMS)(300) particularly useful for translation and rotation measurement of objects having up to five degrees of freedom. A light source (122, 302) provides light beams (124, 304) into at least two channels. Each channel may include an interferometer (310), reflective target (110, 314), beam splitter (128, 312), detector (132, 316), and receiver (318). In concert, the detectors (132, 316) sense horizontal, vertical, and roll position and the receivers (318) sense longitudinal and yaw position change. Optionally, modulation can be imposed on the light beams (124, 304) and phase-sensitive synchronous demodulation used to enhance accuracy.
    Type: Grant
    Filed: August 3, 2006
    Date of Patent: May 20, 2008
    Assignee: Excel Precision Corporation
    Inventor: John C. Tsai
  • Patent number: 7224467
    Abstract: An apparatus for use in rotational measurement. A rotational assembly is provided that is rotationally movable about a rotational axis. At least two interferometers are provided that are each able to receive a respective light beam, separate it into both reference and measuring beams and direct their respective measuring beam to and receive it back from the rotational assembly. The said rotational assembly includes a plurality of cube corners mounted so that at least one is able to receive from and reflect back to one of the interferometers its measuring beam as the rotational assembly rotates. The interferometers combine their reference and measuring beams into respective detection beams, wherein at least one such detection beam includes an interference signal that is process able to determine any rotational measurement of the rotational assembly and any work piece target attached to it.
    Type: Grant
    Filed: August 20, 2004
    Date of Patent: May 29, 2007
    Assignee: Excel Precision Corporation
    Inventor: John C. Tsai
  • Patent number: 7196798
    Abstract: A method establishing a reference point for a machine tool with X-, Y-, and Z-stages. A YZ-plane is established by reflecting a light beam off an X-stage reflector such that the light beam is sensed at an interference detector. The X-stage is moved while repositioning the head and reflector and maintaining sensing. An optical alignment module (OAM) is mounted optically perpendicular to the beam, with a bending mirror centered at the Z-axis. The Z-axis is established by setting the bending mirror to deflect the beam to the Z-axis, reflecting it off of a Z-stage reflector so it is sensed, and moving the Z-stage while repositioning the OAM relative to the X- and Y-axes to maintain sensing. An XY-plane is established by bending mirror deflecting the beam to the Y-axis, reflecting it off of a Y-stage reflector so it is sensed, and moving the Y-stage while repositioning the Y-reflector relative to the X- and Z-axes to maintain sensing.
    Type: Grant
    Filed: June 25, 2004
    Date of Patent: March 27, 2007
    Assignee: Excel Precision Corporation
    Inventor: John C. Tsai
  • Publication number: 20060268281
    Abstract: A position determining system (PDS)(100) or multiple parameters measurement system (MPMS)(300) particularly useful for translation and rotation measurement of objects having up to five degrees of freedom. A light source (122, 302) provides light beams (124, 304) into at least two channels. Each channel may include an interferometer (310), reflective target (110, 314), beam splitter (128, 312), detector (132, 316), and receiver (318). In concert, the detectors (132, 316) sense horizontal, vertical, and roll position and the receivers (318) sense longitudinal and yaw position change. Optionally, modulation can be imposed on the light beams (124, 304) and phase-sensitive synchronous demodulation used to enhance accuracy.
    Type: Application
    Filed: August 3, 2006
    Publication date: November 30, 2006
    Applicant: EXCEL PRECISION CORPORATION
    Inventor: John Tsai
  • Publication number: 20060174721
    Abstract: A measurement system including a machine tool stage having a first piece and a second piece that are movable with respect to one another. A digital scale is integrated in the first piece and a detector is integrated in the second piece at a position suitable to detect movement with respect to the digital scale. The detector creates a signal based upon relative movement between the digital scale and the detector. A display integrated in the second piece receives the signal from the detector and displays a reading of the relative movement thus measured.
    Type: Application
    Filed: March 29, 2006
    Publication date: August 10, 2006
    Applicant: Excel Precision Corporation
    Inventor: John Tsai
  • Publication number: 20050024649
    Abstract: A method establishing a reference point for a machine tool with X-, Y-, and Z-stages. A YZ-plane is established by reflecting a light beam off an X-stage reflector to sense at a detector. The X-stage is moved while repositioning the head and reflector and maintaining sensing. An optical alignment module (OAM) is mounted optically perpendicular to the beam, with a bending mirror centered at the Z-axis. The Z-axis is established bending mirror deflecting the beam to the Z-axis, reflecting it off of a Z-stage reflector so it is sensed, and moving the Z-stage while repositioning the OAM relative to the X- and Y-axes to maintain sensing. An XY-plane is established by bending mirror deflecting the beam to the Y-axis, reflecting it off of a Y-stage reflector so it is sensed, and moving the Y-stage while repositioning the Y-reflector relative to the X- and Z-axes to maintain sensing.
    Type: Application
    Filed: June 25, 2004
    Publication date: February 3, 2005
    Applicant: Excel Precision Corporation
    Inventor: John Tsai
  • Publication number: 20040123684
    Abstract: A measurement system including a stage having a first piece and a second piece that are movable with respect to one another. A digital scale is integrated in the first piece and a detector is integrated in the second piece at a position suitable to detect movement with respect to the digital scale. The detector creates a signal based upon relative movement between the digital scale and the detector. A display integrated in the second piece receives the signal from the detector and displays a reading of the relative movement thus measured.
    Type: Application
    Filed: December 17, 2003
    Publication date: July 1, 2004
    Applicant: Excel Precision Corporation
    Inventor: John C. Tsai
  • Patent number: 6522604
    Abstract: Apparatus (10) and method (100) for inscribing a clock pattern (14), detecting the clock pattern (14) optically, and using the clock pattern (14) to write a sevo pattern in an information storage unit (12), such as a computer hard drive. The clock pattern (14) is inscribed using a marking system (64), which may include a laser (66) or employ other, even non-optical, methods. The clock pattern (14) is inscribable into various locations on a disk platter (16) inside the storage unit (12), including many outside the media surface (26) conventionally used for such in data storage units. While the disk platter (16).is rotating, the clock pattern (14) is on detected using an detection subsystem (46), if desired through a transparent window (36) in a hermetically sealed housing (34) of the storage unit (12), for use in writing the servo pattern with less sector-inconsistency error and off-track error.
    Type: Grant
    Filed: May 15, 2001
    Date of Patent: February 18, 2003
    Assignee: Excel Precision Corporation
    Inventor: John C. Tsai
  • Patent number: 6266298
    Abstract: Apparatus (10) and method (100) for inscribing a clock pattern (14), detecting the clock pattern (14) optically, and using the clock pattern (14) to write a sevo pattern in an information storage unit (12), such as a computer hard drive. The clock pattern (14) is inscribed using a marking system (64), which may include a laser (66) or employ other, even non-optical, methods. The clock pattern (14) is inscribable into various locations on a disk platter (16) inside the storage unit (12), including many outside the media surface (26) conventionally used for such in data storage units. While the disk platter (16) is rotating, the clock pattern (14) is on detected using an detection subsystem (46), if desired through a transparent window (36) in a hermetically sealed housing (34) of the storage unit (12), for use in writing the servo pattern with less sector-inconsistency error and off-track error.
    Type: Grant
    Filed: May 22, 1998
    Date of Patent: July 24, 2001
    Assignee: Excel Precision Corporation
    Inventor: John C. Tsai