Patents by Inventor Chengwu An

Chengwu An 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).

  • Publication number: 20130093419
    Abstract: An apparatus and method of testing a magnetic medium at temperatures of interest is disclosed. Properties of the magnetic medium are determined by focusing light from a source of polarized light on a magnetic surface of the magnetic medium; measuring polarization of resulting reflected light due to the magneto-optical Kerr effect, using, for example a measuring subsystem; and varying the light source to heat the magnetic material where incident to pre-defined temperatures, thereby allowing determination of the magnetic properties using the magneto-optical Kerr effect at said pre-defined temperatures.
    Type: Application
    Filed: June 13, 2011
    Publication date: April 18, 2013
    Applicant: AGENCY FOR SCIENCE, TECHNOLOGY AND RESEARCH
    Inventors: Chengwu An, Kaidong Ye, Qiong Xie, Wendong Song, Kay Siang Tiaw
  • Patent number: 8422096
    Abstract: Disclosed are a method and a computer program product for dissipating heat produced in a scan head assembly of an imaging apparatus during scanning of media sheets in the imaging apparatus. The method includes determining at least one of a temperature of the scan head assembly and a media sheet scan count. The method further includes moving the scan head assembly between a first position of the scan head assembly and a second position of the scan head assembly for dissipating heat, based on at least one of the temperature of the scan head assembly and the media sheet scan count.
    Type: Grant
    Filed: December 8, 2008
    Date of Patent: April 16, 2013
    Assignee: Lexmark International, Inc.
    Inventors: Chengwu Cui, Charles Brandon Langrel
  • Patent number: 8405889
    Abstract: An imaging apparatus includes an automatic document feeder having a media feeding section, a media collecting section and a media conveying path extending from the media feeding section to the media collecting section. The imaging apparatus includes a scan head adjacent to the automatic document feeder. The scan head is moveable to a raised position aligned with a portion of the media conveying path for scanning a media sheet in the portion of the media conveying path.
    Type: Grant
    Filed: May 28, 2010
    Date of Patent: March 26, 2013
    Assignee: Lexmark International, Inc.
    Inventors: Chengwu Cui, Charles Brandon Langrel
  • Patent number: 8400688
    Abstract: A mounting bracket for an image sensing unit of a scanner according to one example embodiment includes a first portion and a second portion extending from the first portion. The first portion has a plurality of elongated holes therein each for receiving a fastener to mount the mounting bracket to a scan head frame. The second portion includes a cutout section therein for allowing an image sensor of the image sensing unit to receive an image from an optical unit of the scanner. A pivot hole in the first portion is centered about a width of the cutout section. When the mounting bracket is mounted on the scan head frame, the elongated holes in the first portion permit linear adjustment of the mounting bracket relative to the scan head frame and the pivot hole permits angular adjustment of the mounting bracket relative to the scan head frame.
    Type: Grant
    Filed: December 28, 2010
    Date of Patent: March 19, 2013
    Assignee: Lexmark International, Inc.
    Inventors: Eugene David Allen, Chengwu Cui, Joshua Tyler Strow
  • Patent number: 8322872
    Abstract: A tubular structure with an opening defined thereon and having an inner surface and an outer surface. The tubular structure being substantially circular in shape and is made of a highly thermal conductive material. A plurality of light sources mounted on the inner surface of the tubular structure. The inner surface is coated with a diffused white coating. Light emitted from the plurality of light sources is reflected from the inner surface before exiting the tubular structure from the opening. This structure ensures emitting a uniform diffused light and prevents non-uniform illumination when disposed in an imaging forming device.
    Type: Grant
    Filed: October 13, 2009
    Date of Patent: December 4, 2012
    Assignee: Lexmark International, Inc.
    Inventors: Chengwu Cui, David Keith Jackson, Joshua Tyler Strow
  • Patent number: 8283622
    Abstract: A method and apparatus for testing a magnetic medium. The method comprises applying a magnetic field of a time-varying strength; directing a polarized optical beam towards a portion of the medium that is in the magnetic field, wherein the optical beam is reflected by a surface of the medium at a point of incidence in the magnetic field; moving the medium relative to the optical beam so as to cause the point of incidence to repeatedly traverse each of a plurality of sectors along a track on the surface; obtaining a series of Kerr signal measurements of the reflected optical beam; grouping measurements into ensembles such that the measurements in an individual ensemble are those obtained while the point of incidence was in a corresponding one of the sectors; and determining at least one magnetic property of at least one of the sectors from the measurements in the corresponding ensemble.
    Type: Grant
    Filed: August 13, 2008
    Date of Patent: October 9, 2012
    Assignee: Agency for Science, Technology and Research
    Inventors: Chengwu An, Kaidong Ye
  • Publication number: 20120212197
    Abstract: A method of generating spurious-noise-free power from a switching device. The method includes generating an oscillating signal in the form of a series of pulse trains, and randomly changing the switching frequency, or the on-time, or both the switching frequency and the on-time of the switching device. The method further includes causing the switching device to change from a first frequency to a second frequency only at the end of a pulse train of the first frequency, and causing the second frequency to start at the beginning of its first pulse train such that no switching duty-cycle disturbance at the time of the change from first to second frequency. In a particular embodiment, the method further generates spurious-noise-free power from a switching device by implementing a relationship between the different switching frequencies involved such that spurious-noise-free operation is achieved.
    Type: Application
    Filed: February 15, 2012
    Publication date: August 23, 2012
    Applicant: IOWA STATE UNIVERSITY RESEARCH FOUNDATION, INC.
    Inventors: Ayman Adel Fayed, Chengwu Tao
  • Publication number: 20120189678
    Abstract: A liposome comprising a phospholipid, a hydrophobic active comprising a carboxylate group, and a component selected from a group consisting of: a hydrophilic adjuvant comprising a positively charged group, a complex of said hydrophobic active with said hydrophilic adjuvant, and combinations thereof. An aqueous liposome dispersion comprising the liposome, and a personal care composition comprising the liposome. A process of preparing the liposome, comprising the steps of: forming a premix by dissolving a phospholipid, a hydrophobic active comprising a carboxylate group in an organic solvent; evaporating off said organic solvent from the premix to form a phospholipid film; and hydrating said lipid film with a hydration medium comprising a hydrophilic adjuvant comprising a positively charged group and homogenize the medium to form an aqueous liposome dispersion.
    Type: Application
    Filed: January 25, 2012
    Publication date: July 26, 2012
    Inventors: Chengwu LI, Naohisa Yoshimi, Xincheng Hu, Shuang Li, Yunhua Gao
  • Patent number: 8228571
    Abstract: Method and image scanning apparatus comprising an image capture unit having an illumination assembly for generating input light; a printed circuit board mounted to the image capture unit, a cooling unit generating an airflow which cools the illumination assembly of the image capture unit as well as the critical components mounted on the printed circuit board and the optical components of the image capture unit; and an adjustable baffle member moveably mounted to the frame of the image scanning apparatus for controlling the path of the airflow relative to the lamp. The cooling unit comprises at least one fan with the fan generating airflow for cooling the lamp of image capture unit.
    Type: Grant
    Filed: December 8, 2008
    Date of Patent: July 24, 2012
    Assignee: Lexmark International, Inc.
    Inventors: James Thomas Beegle, Chengwu Cui, Adam Christopher Kelty, Charles Brandon Langrel, Joshua Tyler Strow
  • Publication number: 20120162726
    Abstract: An illumination assembly for a scanner according to one example embodiment includes a scan head frame. A thermally conductive heat sink component has an elongated base portion that is mounted along a longitudinal edge of the scan head frame and a protruding portion having a generally L-shaped structure that includes a first portion extending from the base portion and a second portion extending from and generally orthogonal to the first portion. A light source is coupled to the second portion of the protruding portion of the heat sink component. A first reflector is removably coupled to the first portion of the protruding portion of the heat sink component and is positioned directly in the optical path of the light source.
    Type: Application
    Filed: December 28, 2010
    Publication date: June 28, 2012
    Inventors: Eugene David Allen, Chengwu Cui, Joshua Tyler Strow
  • Publication number: 20120162738
    Abstract: An illumination assembly for a scanner according to one example embodiment includes a light source, a first reflector and a second reflector. The first reflector has a curved structure and is positioned directly in the optical path of the light source. The first reflector has a first portion and a second portion. The first portion of the first reflector is positioned to reflect light received from the light source toward a target area to be scanned. The second portion of the first reflector is positioned to reflect light received from the light source toward the second reflector. The second reflector is positioned to reflect light received from the first reflector toward the target area.
    Type: Application
    Filed: December 28, 2010
    Publication date: June 28, 2012
    Inventors: Eugene David Allen, Chengwu Cui, Joshua Tyler Strow
  • Publication number: 20120162722
    Abstract: A mounting bracket for an image sensing unit of a scanner according to one example embodiment includes a first portion and a second portion extending from the first portion. The first portion has a plurality of elongated holes therein each for receiving a fastener to mount the mounting bracket to a scan head frame. The second portion includes a cutout section therein for allowing an image sensor of the image sensing unit to receive an image from an optical unit of the scanner. A pivot hole in the first portion is centered about a width of the cutout section. When the mounting bracket is mounted on the scan head frame, the elongated holes in the first portion permit linear adjustment of the mounting bracket relative to the scan head frame and the pivot hole permits angular adjustment of the mounting bracket relative to the scan head frame.
    Type: Application
    Filed: December 28, 2010
    Publication date: June 28, 2012
    Inventors: Eugene David Allen, Chengwu Cui, Joshua Tyler Strow
  • Publication number: 20120162725
    Abstract: Disclosed is an optical system for a scanner that includes at least one light source to illuminate a document, and a plurality of mirrors including a first mirror, a second mirror, a third mirror, a fourth mirror and a fifth mirror. The first mirror is positioned in a direction of the document to receive a light beam therefrom. The second mirror is adapted to receive the light beam reflected from the first mirror. The third mirror is positioned in proximity to the document and is adapted to receive the light beam reflected from the second mirror. The fourth mirror is positioned substantially opposite to the third mirror for receiving the light beam reflected therefrom. The fifth mirror is positioned adjacent to the second mirror and is adapted to receive the light beam reflected from the fourth mirror. The optical system further includes an imaging lens unit and an image sensor.
    Type: Application
    Filed: December 28, 2010
    Publication date: June 28, 2012
    Inventors: Eugene David Allen, Chengwu Cui, Joshua Tyler Strow
  • Patent number: 8159732
    Abstract: An apparatus and methods of use for adjusting a sliding guide rod for an imaging device of a flatbed scanner to improve scanner skew misalignment comprising an attachment member movably mounting the sliding guide rod at one end thereof to one side of the flatbed scanner so as to allow skew-adjusting movement of the sliding guide rod at an opposite end thereof relative to the flatbed scanner and a skew adjustment assembly attached to an opposite side of the flatbed scanner and movably coupling and supporting the opposite end of the sliding guide rod to the opposite side of the flatbed scanner and being actuatable to cause the sliding guide rod to undergo skew adjustment relative to the flatbed scanner to correct scanner skew misalignment of the imaging device.
    Type: Grant
    Filed: October 31, 2008
    Date of Patent: April 17, 2012
    Assignee: Lexmark International, Inc.
    Inventors: Chengwu Cui, Adam Christopher Kelty, Charles Brandon Langrel
  • Patent number: 8089663
    Abstract: A detachable transparent plate for a scan head assembly in a document scanning system that allows an operator to detach the transparent plate from the scan head assembly located above a media feed path to clean a top face of the transparent plate and easily reattach it to the scan head assembly. The scan head assembly has an optical system and a sealing member detachably mounted to a bottom end of the optical system. The transparent plate is received and supported by the sealing member and defines a portion of a bottom surface of the sealing member. The sealing member is detachable from the bottom end of the optical system to allow an operator access to the top face of the transparent plate of the sealing member for cleaning the top face of the transparent plate.
    Type: Grant
    Filed: December 12, 2007
    Date of Patent: January 3, 2012
    Assignee: Lexmark International, Inc.
    Inventors: Chengwu Cui, Charles Brandon Langrel
  • Publication number: 20110310387
    Abstract: A method and apparatus for testing a magnetic medium. The method comprises applying a magnetic field of a time-varying strength; directing a polarized optical beam towards a portion of the medium that is in the magnetic field, wherein the optical beam is reflected by a surface of the medium at a point of incidence in the magnetic field; moving the medium relative to the optical beam so as to cause the point of incidence to repeatedly traverse each of a plurality of sectors along a track on the surface; obtaining a series of Kerr signal measurements of the reflected optical beam; grouping measurements into ensembles such that the measurements in an individual ensemble are those obtained while the point of incidence was in a corresponding one of the sectors; and determining at least one magnetic property of at least one of the sectors from the measurements in the corresponding ensemble.
    Type: Application
    Filed: August 13, 2008
    Publication date: December 22, 2011
    Applicant: Agency for Science, Technology and Research
    Inventors: Chengwu An, Kaidong Ye
  • Patent number: 8081353
    Abstract: A method for providing a visible reference marker on a scanning unit for orienting an item to be scanned or copied includes the steps of emitting a light from a light source, guiding the light to a scanning unit having a contact glass scanning surface, and redirecting the light to define an illuminated reference marker substantially adjacent to the contact glass. A reference marker assembly for accomplishing that method is provided, including a light source, a waveguide for guiding light emitted from the light source to a scanning unit having a contact glass, and a redirector for redirecting the light to define an illuminated reference marker adjacent to the contact glass, for orienting an item to be copied or scanned. The light source may be a light emitting diode, and the redirector may be a light diffuser for redirecting the collected light to define an illuminated reference marker adjacent to the contact glass.
    Type: Grant
    Filed: December 12, 2007
    Date of Patent: December 20, 2011
    Assignee: Lexmark International, Inc.
    Inventors: Charles B. Langrel, Chengwu Cui, Allen W. Waugerman
  • Publication number: 20110292473
    Abstract: An imaging apparatus includes an automatic document feeder having a media feeding section, a media collecting section and a media conveying path extending from the media feeding section to the media collecting section. The imaging apparatus includes a scan head adjacent to the automatic document feeder. The scan head is moveable to a raised position aligned with a portion of the media conveying path for scanning a media sheet in the portion of the media conveying path.
    Type: Application
    Filed: May 28, 2010
    Publication date: December 1, 2011
    Inventors: Chengwu Cui, Charles Brandon Langrel
  • Publication number: 20110105406
    Abstract: The present invention relates to a cosmetic composition comprising: a) from about 0.05% to about 10% of a salt form active; b) from about 0.001% to about 2% of a thickening agent; and c) water, wherein the composition has a turbidity no higher than about 10 NTU, and has a pH in the range of about 5.0 to about 6.8.
    Type: Application
    Filed: October 29, 2010
    Publication date: May 5, 2011
    Applicant: The Proctor & Gamble Company
    Inventors: Chengwu Li, Xincheng Hu
  • Patent number: 7913992
    Abstract: The present application is directed to embodiments for moving a media sheet within a scanning device. The methods include moving the media sheet through a separation mechanism that prevents multiple media sheets from being moved simultaneously along the media path. Further, a buckle is formed in the sheet at a point upstream from a scanner. The buckle acts as a buffer to absorb any load release that could occur as the media sheet exits the separation mechanism. The load release could cause a change in the velocity of the media sheet as it moves across the scanner.
    Type: Grant
    Filed: December 19, 2007
    Date of Patent: March 29, 2011
    Assignee: Lexmark International, Inc.
    Inventors: Charles Brandon Langrel, Chengwu Cui