Patents by Inventor Robert A. Sprague

Robert A. Sprague 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: 20100295880
    Abstract: This application is directed to driving methods for electrophoretic displays. The driving methods comprise grey level waveforms which greatly enhance the pictorial quality of images displayed. The driving method comprises: (a) applying waveform to drive each pixel to the full first color then to a color state of a desired level; or (b) applying waveform to drive each pixel to the full second color then to a color state of a desired level.
    Type: Application
    Filed: August 6, 2010
    Publication date: November 25, 2010
    Inventors: Robert A. Sprague, Craig Lin, Tin Pham, Manasa Peri
  • Publication number: 20100283804
    Abstract: This application is directed to driving methods for electrophoretic displays. The driving methods and waveforms have the advantage that they provide a clean and smooth transition from one image to another image, without flashing or other undesired visual interruptions. The methods also provide faster image transitions. In an embodiment, a method drives a display device from a first image to a second image wherein images of a first color are displayed with a background of a second color, which method comprises driving pixels of the first color directly to the second color before driving pixels of the second color directly to the first color.
    Type: Application
    Filed: May 3, 2010
    Publication date: November 11, 2010
    Inventors: Robert Sprague, Bryan Chan, Tin Pham, Craig Lin, Manasa Peri
  • Patent number: 7830592
    Abstract: The present invention relates to a process for manufacturing a brightness enhancement structure comprising micro-reflectors. The process comprises forming an array of micro-structures by embossing; and depositing a metal layer over the surface of the micro-structures. The present invention also relates to a process for manufacturing a display device comprising micro-reflectors. The present invention further relates to a display device comprising micro-reflectors.
    Type: Grant
    Filed: November 25, 2008
    Date of Patent: November 9, 2010
    Assignee: SiPix Imaging, Inc.
    Inventors: Robert A. Sprague, Yi-Shung Chaug, HongMei Zang, Xiaojia Wang, Gary Kang
  • Publication number: 20100271407
    Abstract: The present invention is directed to reflective display devices with a luminance enhancement structure on its viewing side and at least an auxiliary layer and/or edge sealing. The structure increases the overall reflectance by reducing the total internal reflection, and as a result, the brightness of a display device is increased.
    Type: Application
    Filed: April 20, 2010
    Publication date: October 28, 2010
    Inventors: Andrew Ho, Bryan Chan, Craig Lin, Robert A. Sprague
  • Publication number: 20100225999
    Abstract: The present invention is directed to luminance enhancement structures for reflective display devices. The structure comprises columns and grooves, wherein each of said grooves has a cross-section comprising an apex angle and two edge lines. The structure increases the overall reflectance by reducing the total internal reflection, and as a result, the brightness of a display device is increased.
    Type: Application
    Filed: March 8, 2010
    Publication date: September 9, 2010
    Inventors: Craig Lin, Robert A. Sprague
  • Publication number: 20100165448
    Abstract: The present invention is directed to an alternative design of a multicolor display. The display device is capable of achieving high quality black and white states. The pixel electrodes and the microcups in the display device may be aligned only in one axis. In practice, a standard active matrix array may be used to drive the display device.
    Type: Application
    Filed: December 22, 2009
    Publication date: July 1, 2010
    Inventor: Robert A. Sprague
  • Publication number: 20100165005
    Abstract: The present invention is directed to a highlight color display. One of the key features of the invention is the dark color of the display fluid filled in the microcups, which allows the dark state to appear black. There is no alignment required between the pixel electrodes and the microcups. In practice, a standard active matrix array may be used to drive the display device.
    Type: Application
    Filed: December 22, 2009
    Publication date: July 1, 2010
    Inventor: Robert A. Sprague
  • Publication number: 20100134538
    Abstract: This application is directed to driving methods for electrophoretic displays. The driving methods comprise grey level waveforms which greatly enhance the pictorial quality of images displayed. The driving method comprises: (a) applying waveform to drive each pixel from its initial color state to the full first color then to a color state of a desired level; or (b) applying waveform to drive each pixel from its initial color state to the full second color then to a color state of a desired level.
    Type: Application
    Filed: December 7, 2009
    Publication date: June 3, 2010
    Inventors: Robert A. Sprague, Craig Lin, Tin Pham, Manasa Peri
  • Publication number: 20100103501
    Abstract: This invention relates to a display device comprising a plurality of display cells, wherein said display cells are separated by slanted partition walls. This invention also relates to a display device comprising a plurality of display cells, wherein said display cells are separated by indented partition walls having indented areas. The electrophoretic structures of the present invention may be manufactured by a continuous or semi-continuous roll-to-roll manufacturing process. The structures in which display cells are separated by slanted partition walls or partition walls having indented areas are capable of providing enhanced color states.
    Type: Application
    Filed: October 27, 2009
    Publication date: April 29, 2010
    Inventors: Xiaojia WANG, Robert A. SPRAGUE, Gary Yih-Ming KANG
  • Publication number: 20100053728
    Abstract: The color display of the present invention involves a two particle system and is capable of displaying multiple colors with high quality black and white states. The color states are suitable for highlighting function. The color display does not require alignment between the electrodes and the display cells in which a display fluid is filled, which significantly reduces the complexity of the design and also lowers the manufacturing costs.
    Type: Application
    Filed: August 25, 2009
    Publication date: March 4, 2010
    Inventors: Craig Lin, Robert A. Sprague
  • Patent number: 7671834
    Abstract: An electric writable medium having islanded surface structures operationally configured to avoid tribocharging of the electric writable medium.
    Type: Grant
    Filed: August 8, 2005
    Date of Patent: March 2, 2010
    Assignee: Xerox Corporation
    Inventor: Robert A. Sprague
  • Publication number: 20090273827
    Abstract: The present invention is directed to color display devices in which each display cell is capable of displaying three color states. The display fluid filled in the display cells comprises two types of pigment particles. The color display device may further comprise a brightness enhancement structure on its viewing side.
    Type: Application
    Filed: April 29, 2009
    Publication date: November 5, 2009
    Inventors: Craig Lin, Robert A. Sprague
  • Publication number: 20090267970
    Abstract: The disclosure relates to driving methods for bistable displays, in particular, driving methods comprising interleaving driving waveforms.
    Type: Application
    Filed: April 21, 2009
    Publication date: October 29, 2009
    Inventors: Jialock Wong, Yajuan Chen, Robert Sprague, Hongmei Zang
  • Publication number: 20090251763
    Abstract: The present invention is directed to color display devices which are capable of displaying multiple color states. The display device comprises a plurality of display cells, wherein each of said display cells is (a) sandwiched between a first layer comprising a common electrode and a second layer comprising a plurality of driving electrodes, wherein at least one of the driving electrodes is a designated electrode, (b) filled with an electrophoretic fluid comprising at least two types of pigment particles dispersed in a solvent or solvent mixture, and (c) capable of displaying at least four color states. The display device may also comprise hiding layers or a brightness enhancement structure on the viewing side.
    Type: Application
    Filed: April 1, 2009
    Publication date: October 8, 2009
    Inventors: Robert A. SPRAGUE, Craig LIN
  • Publication number: 20090213452
    Abstract: The present invention is directed to color display devices. The color display devices comprise display cells which is capable of displaying multiple color states. The display device may also comprise black matrix layers or a brightness enhancement structure on the viewing side. The present invention is directed to a display device comprising a plurality of display cells, wherein each of said display cells is sandwiched between a first layer comprising a common electrode and a second layer comprising a plurality of driving electrodes and at least one of the driving electrodes is a designated electrode, and said display device further comprises blocking layers on its viewing side and said blocking layers are located in positions corresponding to the designated electrodes.
    Type: Application
    Filed: February 12, 2009
    Publication date: August 27, 2009
    Inventors: Craig LIN, Robert A. Sprague
  • Publication number: 20090096745
    Abstract: The present invention is directed to methods for adjusting or selecting driving waveforms in order to achieve a consistent optical performance of a display device. When a method of the present invention is applied, even if there are changes in the display medium due to temperature variation, photo-exposure or aging, the optical performance can be maintained at a desired level.
    Type: Application
    Filed: October 10, 2008
    Publication date: April 16, 2009
    Inventors: Robert A. Sprague, Bryan Hans Chan, Yajuan Chen, Haiyan Gu, Craig Lin, Andrew Ho, Tin Pham, Wanheng Wang
  • Patent number: 7479942
    Abstract: Methods and systems for writing and erasing electric writeable media are disclosed. An electric writeable medium may include a backplane electrode, a display layer including a plurality of elements and a top layer. The medium may further include a plurality of island electrodes. To enable writing to the medium, a stylus is charged to a positive voltage and the backplane electrode is grounded. The stylus is applied to the top layer and/or the island electrodes to deposit charge, which causes proximate elements to display a first color. If the top layer is a resistive layer, grounding the resistive layer and applying a positive voltage to the backplane electrode sufficient to change the displayed color of the elements erases the medium. If the top layer is a photoconductive layer, a light source is further required to enable the photoconductive layer to operate as an electrode when erasing the medium.
    Type: Grant
    Filed: June 25, 2004
    Date of Patent: January 20, 2009
    Assignee: Xerox Corporation
    Inventors: Robert A. Sprague, Tin Pham
  • Publication number: 20080303780
    Abstract: The disclosure is directed toward driving methods and a driving circuit which are particularly suitable for bi-stable displays. In certain embodiments, methods provide the fastest and most pleasing appearance to the desired image while maintaining the optimal image quality over the life expectancy of an electrophoretic display device.
    Type: Application
    Filed: June 3, 2008
    Publication date: December 11, 2008
    Inventors: Robert Sprague, Andrew Ho, Yajuan Chen, Hongmei Zang, Jialock Wong, Chein Wang
  • Publication number: 20080218471
    Abstract: An electrophoretic display (EPD) with thermal control is disclosed for controlling and maintaining an image in extreme temperature environments. Techniques are also disclosed for maintaining the EPD cell threshold voltage for EPD cells comprising an EPD display media at or above a desired level in an environment in which the EPD may be subjected to an extreme temperature. The techniques comprise sensing a sensed temperature associated with the EPD display media, determining whether the sensed temperature satisfies a criterion established to ensure that the display media temperature remains at a level associated with an acceptable EPD cell threshold voltage, and in the event it is determined that the sensed temperature does not satisfy the criterion, controlling the EPD display media temperature as required to bring the sensed temperature to a level that satisfies the criterion.
    Type: Application
    Filed: June 22, 2007
    Publication date: September 11, 2008
    Inventors: Jerry Chung, Rong-Chang Liang, Robert A. Sprague
  • Patent number: 7375634
    Abstract: An electronic signage for directing persons to desired locations.
    Type: Grant
    Filed: August 8, 2005
    Date of Patent: May 20, 2008
    Assignee: Xerox Corporation
    Inventor: Robert A. Sprague