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: 20210191246
    Abstract: Wavelength conversion elements formed from phosphors and dielectric interference particles dispersed in a host material, either in a single layer or in separate layers, are disclosed. Optical light conversion devices having such wavelength conversion elements, methods of making such wavelength conversion elements, and methods of using such wavelength conversion elements are also disclosed.
    Type: Application
    Filed: July 25, 2019
    Publication date: June 24, 2021
    Inventors: ROBERT SPRAGUE, MICHAEL P. NEWELL
  • Patent number: 10871644
    Abstract: Phosphor elements comprising phosphors in a host material having a phosphorescence-emitting surface with surface nanostructures are disclosed. Phosphor wheels having such phosphor elements, methods of making such phosphor elements, and methods of using such phosphor elements are also disclosed.
    Type: Grant
    Filed: August 16, 2019
    Date of Patent: December 22, 2020
    Assignee: Materion Corporation
    Inventors: Robert Sprague, Michael P. Newell
  • Publication number: 20200116911
    Abstract: In a method of manufacturing a one-dimensionally varying optical filter, a substrate is coated to form a stack of layers of two or more different types. The coating may, for example, employ sputtering, electron-beam evaporation, or thermal evaporation. During the coating, the time-averaged deposition rate is varied along an optical gradient direction by generating reciprocation between a shadow mask and the substrate in a reciprocation direction that is transverse to the optical gradient direction. In some approaches, the shadow mask is periodic with a mask period defined along the direction of reciprocation, and the generated reciprocation has a stroke equal to or greater than the mask period along the direction of reciprocation. The substrate and the shadow mask may also be rotated together as a unit during the coating. Also disclosed are one-dimensionally varying optical filters, such as linear variable filters, made by such methods.
    Type: Application
    Filed: December 10, 2019
    Publication date: April 16, 2020
    Inventor: Robert Sprague
  • Patent number: 10578943
    Abstract: The present invention is directed to an electrophoretic fluid which comprises additive particles. The concentration of the additive particles in the electrophoretic fluid does not exceed 25% by weight and the additive particles are not seen at the viewing side during operation of the display. The resulting fluid can improve optical performance of a display device, such as image stability and contrast ratio. The present invention is also directed to an electrophoretic display comprising the electrophoretic fluid.
    Type: Grant
    Filed: August 28, 2017
    Date of Patent: March 3, 2020
    Assignee: E INK CALIFORNIA, LLC
    Inventors: Ming Wang, Yu Li, Hui Du, Haiyan Gu, Roman Ivanov, Robert A. Sprague, HongMei Zang, Xiaojia Zhang
  • Patent number: 10535312
    Abstract: A method for driving a display having a plurality of pixels, where each pixel is capable of displaying a first color or a second color and is sandwiched between a first electrode and a pixel electrode, the method including applying a driving sequence which includes: (a) for a first time period, applying a first voltage potential between the first electrode and each of the pixel electrodes of a first group of pixels, and applying no voltage potential between the first electrode and each of the pixel electrodes of a second group of pixels of the second color, thereby causing the display device to display an image of the first color with a background of the second color; and (b) for a second time period, applying no voltage potential between the first electrode and each of the pixel electrodes of the first group of pixels, and applying a second voltage potential to each of the pixel electrodes corresponding to the second group of pixels, to clear the onetime image created in step (a).
    Type: Grant
    Filed: May 22, 2018
    Date of Patent: January 14, 2020
    Assignee: E INK CALIFORNIA, LLC
    Inventors: Robert A. Sprague, Andrew Ho, Yajuan Chen, HongMei Zang, Jialock Wong, Chein Wang
  • Publication number: 20190377173
    Abstract: Phosphor elements comprising phosphors in a host material having a phosphorescence-emitting surface with surface nanostructures are disclosed. Phosphor wheels having such phosphor elements, methods of making such phosphor elements, and methods of using such phosphor elements are also disclosed.
    Type: Application
    Filed: August 16, 2019
    Publication date: December 12, 2019
    Inventors: Robert Sprague, Michael P. Newell
  • Patent number: 10502880
    Abstract: In a method of manufacturing a one-dimensionally varying optical filter, a substrate is coated to form a stack of layers of two or more different types. The coating may, for example, employ sputtering, electron-beam evaporation, or thermal evaporation. During the coating, the time-averaged deposition rate is varied along an optical gradient direction by generating reciprocation between a shadow mask and the substrate in a reciprocation direction that is transverse to the optical gradient direction. In some approaches, the shadow mask is periodic with a mask period defined along the direction of reciprocation, and the generated reciprocation has a stroke equal to or greater than the mask period along the direction of reciprocation. The substrate and the shadow mask may also be rotated together as a unit during the coating. Also disclosed are one-dimensionally varying optical filters, such as linear variable filters, made by such methods.
    Type: Grant
    Filed: October 30, 2017
    Date of Patent: December 10, 2019
    Assignee: MATERION CORPORATION
    Inventor: Robert Sprague
  • Patent number: 10437042
    Abstract: Phosphor elements comprising phosphors in a host material having a phosphorescence-emitting surface with surface nanostructures are disclosed. Phosphor wheels having such phosphor elements, methods of making such phosphor elements, and methods of using such phosphor elements are also disclosed.
    Type: Grant
    Filed: February 10, 2017
    Date of Patent: October 8, 2019
    Assignee: MATERION CORPORATION
    Inventors: Robert Sprague, Michael P. Newell
  • Publication number: 20190212484
    Abstract: An interference filter includes a layers stack comprising a plurality of layers of at least: layers of amorphous hydrogenated silicon with added nitrogen (a-Si:H,N) and layers of one or more dielectric materials, such as SiO2, SiOx, SiOxNy, a dielectric material with a higher refractive index in the range 1.9 to 2.7 inclusive, or so forth. The interference filter is designed to have a passband center wavelength in the range 750-1000 nm inclusive. Added nitrogen in the a-Si:H,N layers provides improved transmission in the passband without a large decrease in refractive index observed in a-Si:H with comparable transmission. Layers of a dielectric material with a higher refractive index in the range 1.9 to 2.7 inclusive provide a smaller angle shift compared with a similar interference filter using SiO2 as the low index layers.
    Type: Application
    Filed: March 19, 2019
    Publication date: July 11, 2019
    Inventors: Robert Sprague, Shengyuan Bai
  • Patent number: 10288975
    Abstract: The present invention is directed to an electrophoretic dispersion comprising charged pigment particles, in particular, an electrophoretic dispersion including both uncharged or lightly charged neutral buoyancy particles and uncharged or lightly charged additive particles. The combination improves the performance of an electrophoretic display, in particular the color state stability over time.
    Type: Grant
    Filed: November 6, 2017
    Date of Patent: May 14, 2019
    Assignee: E INK CALIFORNIA, LLC
    Inventors: Robert A. Sprague, Bo-Ru Yang, Peter B. Laxton
  • Publication number: 20180277045
    Abstract: A method for driving a display having a plurality of pixels, where each pixel is capable of displaying a first color or a second color and is sandwiched between a first electrode and a pixel electrode, the method including applying a driving sequence which includes: (a) for a first time period, applying a first voltage potential between the first electrode and each of the pixel electrodes of a first group of pixels, and applying no voltage potential between the first electrode and each of the pixel electrodes of a second group of pixels of the second color, thereby causing the display device to display an image of the first color with a background of the second color; and (b) for a second time period, applying no voltage potential between the first electrode and each of the pixel electrodes of the first group of pixels, and applying a second voltage potential to each of the pixel electrodes corresponding to the second group of pixels, to clear the onetime image created in step (a).
    Type: Application
    Filed: May 22, 2018
    Publication date: September 27, 2018
    Inventors: Robert A. SPRAGUE, Andrew HO, Yajuan CHEN, HongMei ZANG, Jialock WONG, Chein WANG
  • Patent number: 10002575
    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: Grant
    Filed: May 6, 2016
    Date of Patent: June 19, 2018
    Assignee: E INK CALIFORNIA, LLC
    Inventors: Robert A. Sprague, Andrew Ho, Yajuan Chen, HongMei Zang, Jialock Wong, Chein Wang
  • Patent number: 9989684
    Abstract: An interference filter includes a layers stack comprising a plurality of layers of at least: layers of amorphous hydrogenated silicon with added nitrogen (a-Si:H,N) and layers of one or more dielectric materials, such as SiO2, SiOx, SiOxNy, a dielectric material with a higher refractive index in the range 1.9 to 2.7 inclusive, or so forth. The interference filter is designed to have a passband center wavelength in the range 750-1000 nm inclusive. Layers of a dielectric material with a higher refractive index in the range 1.9 to 2.7 inclusive provide a smaller angle shift compared with a similar interference filter using SiO2 as the low index layers.
    Type: Grant
    Filed: January 22, 2016
    Date of Patent: June 5, 2018
    Assignee: MATERION CORPORATION
    Inventor: Robert Sprague
  • Patent number: 9927369
    Abstract: Devices and methods are disclosed for characterizing point flaws (including pinholes and point defects) of an optical filter. A passband test is performed, including: illuminating the optical filter with passband illumination whose spectral range at least overlaps a passband of the optical filter; acquiring a passband map of the optical filter using a two-dimensional array of photodetectors while illuminating the optical filter with the passband illumination; and identifying point defects of the optical filter as low intensity locations of the passband map. A stopband test is performed, including: illuminating the optical filter with stopband illumination whose spectral range lies entirely outside of the passband of the optical filter; acquiring a stopband map of the optical filter using the two-dimensional array of photodetectors while illuminating the optical filter with the stopband illumination; and identifying pinholes of the optical filter as high intensity locations of the stopband map.
    Type: Grant
    Filed: June 3, 2016
    Date of Patent: March 27, 2018
    Assignee: MATERION CORPORATION
    Inventor: Robert Sprague
  • Publication number: 20180059500
    Abstract: The present invention is directed to an electrophoretic dispersion comprising charged pigment particles, in particular, an electrophoretic dispersion including both uncharged or lightly charged neutral buoyancy particles and uncharged or lightly charged additive particles. The combination improves the performance of an electrophoretic display, in particular the color state stability over time.
    Type: Application
    Filed: November 6, 2017
    Publication date: March 1, 2018
    Inventors: Robert A. SPRAGUE, Bo-Ru YANG, Peter B. LAXTON
  • Publication number: 20180052265
    Abstract: In a method of manufacturing a one-dimensionally varying optical filter, a substrate is coated to form a stack of layers of two or more different types. The coating may, for example, employ sputtering, electron-beam evaporation, or thermal evaporation. During the coating, the time-averaged deposition rate is varied along an optical gradient direction by generating reciprocation between a shadow mask and the substrate in a reciprocation direction that is transverse to the optical gradient direction. In some approaches, the shadow mask is periodic with a mask period defined along the direction of reciprocation, and the generated reciprocation has a stroke equal to or greater than the mask period along the direction of reciprocation. The substrate and the shadow mask may also be rotated together as a unit during the coating. Also disclosed are one-dimensionally varying optical filters, such as linear variable filters, made by such methods.
    Type: Application
    Filed: October 30, 2017
    Publication date: February 22, 2018
    Inventor: Robert Sprague
  • Publication number: 20170357137
    Abstract: The present invention is directed to an electrophoretic fluid which comprises additive particles. The concentration of the additive particles in the electrophoretic fluid does not exceed 25% by weight and the additive particles are not seen at the viewing side during operation of the display. The resulting fluid can improve optical performance of a display device, such as image stability and contrast ratio. The present invention is also directed to an electrophoretic display comprising the electrophoretic fluid.
    Type: Application
    Filed: August 28, 2017
    Publication date: December 14, 2017
    Inventors: Ming WANG, Yu LI, Hui DU, Haiyan GU, Roman IVANOV, Robert A. SPRAGUE, HongMei ZANG, Xiaojia ZHANG
  • Patent number: 9835926
    Abstract: The present invention is directed to an electrophoretic dispersion, in particular, an electrophoretic dispersion comprising uncharged or lightly charged additive particles for improving bistability of an electrophoretic display. The average diameter of the additive particles is about 1% to about 25% of the average hydrodynamic diameter of the charged pigment particles.
    Type: Grant
    Filed: May 18, 2015
    Date of Patent: December 5, 2017
    Assignee: E INK CALIFORNIA, LLC
    Inventors: Robert A. Sprague, Bo-Ru Yang, Peter B. Laxton
  • Patent number: 9804310
    Abstract: In a method of manufacturing a one-dimensionally varying optical filter, a substrate is coated to form a stack of layers of two or more different types. The coating may, for example, employ sputtering, electron-beam evaporation, or thermal evaporation. During the coating, the time-averaged deposition rate is varied along an optical gradient direction by generating reciprocation between a shadow mask and the substrate in a reciprocation direction that is transverse to the optical gradient direction. In some approaches, the shadow mask is periodic with a mask period defined along the direction of reciprocation, and the generated reciprocation has a stroke equal to or greater than the mask period along the direction of reciprocation. The substrate and the shadow mask may also be rotated together as a unit during the coating. Also disclosed are one-dimensionally varying optical filters, such as linear variable filters, made by such methods.
    Type: Grant
    Filed: February 17, 2016
    Date of Patent: October 31, 2017
    Assignee: Materion Corporation
    Inventor: Robert Sprague
  • Patent number: 9778537
    Abstract: The present invention is directed to an electrophoretic fluid which comprises additive particles. The concentration of the additive particles in the electrophoretic fluid is 2.5% to 25% by weight and the additive particles are not seen at the viewing side during operation of the display. The resulting fluid can improve optical performance of a display device, such as image stability and contrast ratio. The present invention is also directed to an electrophoretic display comprising the electrophoretic fluid.
    Type: Grant
    Filed: January 21, 2016
    Date of Patent: October 3, 2017
    Assignee: E INK CALIFORNIA, LLC
    Inventors: Ming Wang, Yu Li, Hui Du, Xiaojia Zhang, Haiyan Gu, Roman Ivanov, Robert A. Sprague, HongMei Zang