Patents by Inventor Yimin Ji

Yimin Ji 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: 11906823
    Abstract: A reconfigurable polarization rotator is formed of an array of very small liquid crystal (LC) cells (e.g., cells of less than 10 ?m in width, termed “microcells”), referred to hereinafter as “microcells”. Each LC microcell is addressable by a separate electrical voltage input that independently controls the polarization rotation performed by the associated LC microcell. By defining a set of adjacent microcells to be held at the same voltage level, that group may be used to form a polarization rotator window of a proper size for a first fiber array configuration. When a fiber array of a different configuration (say, an array with twice the pitch) is used, a different-sized group of adjacent LC microcells is held at a common voltage level so as to form a reconfigured “window” of a new dimension.
    Type: Grant
    Filed: April 20, 2021
    Date of Patent: February 20, 2024
    Assignee: II-VI Delaware, Inc.
    Inventors: Guomin Jiang, Helen Chen, Haiji J. Yuan, Lixin Wang, WenYi Cao, Xuewen Lu, Qingyu Li, Yimin Ji
  • Patent number: 11789331
    Abstract: A voltage-controlled optical wedge is formed by creating an adjustable voltage gradient along the length of a relatively large-sized LC cell. A pair of bias voltages (AC voltages) are applied at the opposing side terminations of the LC cell, their RMS values selected to create a continuous phase variation along the length of the cell, where a defined phase variation is associated with a specific beam steering angle. Adjustments in the applied bias voltages (specifically, changes in the RMS values of the bias voltages) result in changing the beam steering angle, providing for active, controllable beam steering as a function of time. The LC cell may be configured to provide either a linear or nonlinear continuous phase variation, as preferred for different beam steering applications.
    Type: Grant
    Filed: June 23, 2022
    Date of Patent: October 17, 2023
    Inventors: Qingyu Li, Jack R. Kelly, Guomin Jiang, Haiji J. Yuan, Yimin Ji, Helen Chen
  • Publication number: 20230061448
    Abstract: A module handles beams having multiple channels in an optical network. The module has a dispersion element, a liquid crystal (LC) based switching assembly, and photodetectors. The dispersion element is arranged in optical communication with the beams from inputs and is configured to disperse the beams into the channels across a dispersion direction. The switching assembly is arranged in optical communication with the channels from the dispersion element and is configured to selectively reflect the channels using electrically switchable cells of one or more LC-based switching engines. The photodetectors are arranged in optical communication with the dispersion element, and each are configured to receive selectively reflected channels for optical channel monitoring. Outputs can be arranged in optical communication with the dispersion element and can be configured to receive selectively reflected channels for wavelength selective switching.
    Type: Application
    Filed: October 20, 2022
    Publication date: March 2, 2023
    Inventors: Guomin JIANG, Helen CHEN, Xuewen LU, Lixin WANG, Qingyu LI, Haiji YUAN, Yimin JI, Wenyi CAO
  • Publication number: 20220357630
    Abstract: A voltage-controlled optical wedge is formed by creating an adjustable voltage gradient along the length of a relatively large-sized LC cell. A pair of bias voltages (AC voltages) are applied at the opposing side terminations of the LC cell, their RMS values selected to create a continuous phase variation along the length of the cell, where a defined phase variation is associated with a specific beam steering angle. Adjustments in the applied bias voltages (specifically, changes in the RMS values of the bias voltages) result in changing the beam steering angle, providing for active, controllable beam steering as a function of time. The LC cell may be configured to provide either a linear or nonlinear continuous phase variation, as preferred for different beam steering applications.
    Type: Application
    Filed: June 23, 2022
    Publication date: November 10, 2022
    Applicant: II-VI Delaware, Inc.
    Inventors: Qingyu Li, Jack R. Kelly, Guomin Jiang, Haiji J. Yuan, Yimin Ji, Helen Chen
  • Publication number: 20220334416
    Abstract: A reconfigurable polarization rotator is formed of an array of very small liquid crystal (LC) cells (e.g., cells of less than 10 ?m in width, termed “microcells”), referred to hereinafter as “microcells”. Each LC microcell is addressable by a separate electrical voltage input that independently controls the polarization rotation performed by the associated LC microcell. By defining a set of adjacent microcells to be held at the same voltage level, that group may be used to form a polarization rotator window of a proper size for a first fiber array configuration. When a fiber array of a different configuration (say, an array with twice the pitch) is used, a different-sized group of adjacent LC microcells is held at a common voltage level so as to form a reconfigured “window” of a new dimension.
    Type: Application
    Filed: April 20, 2021
    Publication date: October 20, 2022
    Applicant: II-VI Delaware, Inc.
    Inventors: Guomin Jiang, Helen Chen, Haiji J. Yuan, Lixin Wang, WenYi Cao, Xuewen Lu, Qingyu Li, Yimin Ji
  • Patent number: 11422429
    Abstract: A voltage-controlled optical wedge is formed by creating an adjustable voltage gradient along the length of a relatively large-sized LC cell. A pair of bias voltages (AC voltages) are applied at the opposing side terminations of the LC cell, their RMS values selected to create a continuous phase variation along the length of the cell, where a defined phase variation is associated with a specific beam steering angle. Adjustments in the applied bias voltages (specifically, changes in the RMS values of the bias voltages) result in changing the beam steering angle, providing for active, controllable beam steering as a function of time. The LC cell may be configured to provide either a linear or nonlinear continuous phase variation, as preferred for different beam steering applications.
    Type: Grant
    Filed: April 21, 2021
    Date of Patent: August 23, 2022
    Assignee: II-VI Delaware, Inc.
    Inventors: Qingyu Li, Jack R. Kelly, Guomin Jiang, Haiji J. Yuan, Yimin Ji, Helen Chen
  • Publication number: 20220252793
    Abstract: A module handles beams having multiple channels in an optical network. The module has a dispersion element, a liquid crystal (LC) based switching assembly, and photodetectors. The dispersion element is arranged in optical communication with the beams from inputs and is configured to disperse the beams into the channels across a dispersion direction. The switching assembly is arranged in optical communication with the channels from the dispersion element and is configured to selectively reflect the channels using electrically switchable cells of one or more LC-based switching engines. The photodetectors are arranged in optical communication with the dispersion element, and each are configured to receive selectively reflected channels for optical channel monitoring. Outputs can be arranged in optical communication with the dispersion element and can be configured to receive selectively reflected channels for wavelength selective switching.
    Type: Application
    Filed: April 29, 2021
    Publication date: August 11, 2022
    Inventors: Guomin JIANG, Helen CHEN, Xuewen LU, Lixin WANG, Qingyu LI, Haiji Jimmy YUAN, Yimin JI, WenYi CAO
  • Publication number: 20100097330
    Abstract: One disclosed feature of the embodiments is a method and apparatus to provide a touch screen. First and second layers having inner surfaces coated with indium tin oxide (ITO) are formed. The coated surfaces have a first refractive index. A cavity is formed by the first and second layers and a sealant that seals perimeter of the first and second layers. A fluid is filled in the cavity. The fluid has a second refractive index.
    Type: Application
    Filed: October 16, 2008
    Publication date: April 22, 2010
    Inventors: James Y. Lee, Yimin Ji
  • Publication number: 20030058517
    Abstract: An optical system of the present invention includes a reflective liquid crystal device having a plurality of independently activated liquid crystal elements, and an optical element for directing a plurality of input light beams at the reflective liquid crystal device such that each input light beam impinges upon one of the liquid crystal elements. Each liquid crystal element of the reflective liquid crystal device includes a transparent first electrode, a reflective second electrode spaced apart from the first electrode, and a liquid crystal medium disposed between the first and second electrodes. The liquid crystal elements are independently operable to change between half-wave and zero retardation states in response to an applied voltage.
    Type: Application
    Filed: April 12, 2002
    Publication date: March 27, 2003
    Inventors: Robert G. Lindquist, John P. Kondis, Yimin Ji, Rui-Qing Ma
  • Publication number: 20030058516
    Abstract: An optical system according to the present invention includes a beam polarization combiner for receiving first and second sets of input beams, and a reflective spatial light modulator having a plurality of individually activated modulating elements each corresponding to a respective one of the different wavelengths of the input beams. Each input beam is directed at a modulating element of corresponding wavelength with input beams of the first and second sets impinging upon the modulating element from respective first and second incoming paths. Each modulating element selectively changes the input beams such that the outgoing path for each reflected beam of each set is superimposed on the incoming path for the other set. The beam combiner receives the reflected sets of beams and directs them in different directions based upon their polarization. The optical system may be used in a wavelength selective switch or a dynamic spectral equalizer.
    Type: Application
    Filed: April 12, 2002
    Publication date: March 27, 2003
    Inventors: Bradley A. Scott, Robert G. Lindquist, Yimin Ji, Rui-Qing Ma, John P. Kondis
  • Patent number: 5963289
    Abstract: A method of manufacturing liquid crystal on silicon devices uses asymmetric placement of scribes on silicon and glass substrate layers to maximize the yield of processed active matrix silicon wafers. Asymmetrical scribing minimizes a dimension from a gasket seal between the substrates to a lower bond pad edge. An opposite glass overhang provides an interconnect redundancy for an ITO plate or a repair site for electrical contact to the ITO plate. Methods of device separation employing partial sawing are also employed.
    Type: Grant
    Filed: October 27, 1997
    Date of Patent: October 5, 1999
    Assignee: S Vision
    Inventors: Michael E. Stefanov, John H. Erdmann, Christopher Frank, Yimin Ji
  • Patent number: 5929960
    Abstract: A method for forming walls (8) between substrates (11, 12) in a liquid crystal cell (10) includes the step of forming a cell with a liquid crystal-monomer mixture (50). The cell (10) is then exposed to ultraviolet light (70) causing the monomer to be selectively polymerized to form walls (8) between substrates (11, 12) of the cell. The monomer is selectively polymerized by applying an electric field across the cell through a patterned conductive coating (31, 32) on each substrate (11, 12) to separate the dispersed monomer to the low field, interpixel regions (72). The cell (10) is then exposed to ultraviolet light (70) to polymerize the separated monomer to form the walls (8) in the low field regions (72).
    Type: Grant
    Filed: October 17, 1997
    Date of Patent: July 27, 1999
    Assignee: Kent State University
    Inventors: John L. West, Marc Rouberol, Yimin Ji, James J. Francl