Patents by Inventor Zhengnan YUAN

Zhengnan YUAN 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: 11880114
    Abstract: Techniques for using ferroelectric liquid crystals Dammann grating (FLCDG) for light detection and ranging devices are disclosed. In LiDAR devices, accuracy, response time, and cost performance can be limited by some factors, such as laser pulse width, time resolution of a time-to-digital conversion chip, detector bandwidth, shot noise, and time error generated by electronic circuits. A FLCDG-based architecture can improve a LiDAR device, and provide for one-shot capturing due to the high switching speed at very low driving voltage provided by ferroelectric liquid crystals and the equal diffracting ability of Dammann grating.
    Type: Grant
    Filed: August 27, 2020
    Date of Patent: January 23, 2024
    Assignee: THE HONG KONG UNIVERSITY OF SCIENCE AND TECHNOLOGY
    Inventors: Zhengnan Yuan, Abhishek Kumar Srivastava, Zhibo Sun, Hoi Sing Kwok
  • Publication number: 20230250338
    Abstract: There is provided a ferroelectric liquid crystal (FLC) material for the deformed helix FLC (DHFLC) electro-optical mode devices and shows optimum electro-optical properties including high tilt angle (>38°), and short helix pitch (<120 nm), and spontaneous polarization (>100 nC/cm2) comprising at least two components, wherein at least one FLC component is a chiral compound of Formula (I): particularly: wherein W1 and W2 are chiral groups with polar substituent at chiral centre, A and B are independently N atom or CH groups providing that at least one of A or B is N atom. Other various groups are as defined herein.
    Type: Application
    Filed: February 7, 2023
    Publication date: August 10, 2023
    Inventors: Valerii Vladimirovich VASHCHENKO, Olena V. VASHCHENKO, Abhishek Kumar SRIVASTAVA, Zhibo SUN, Zhengnan YUAN, Hoi Sing KWOK
  • Publication number: 20230244102
    Abstract: One or more devices, systems, methods and/or apparatus to facilitate suppression of fringe field effect, such as for diffraction grating and/or display purposes. In one embodiment, a ferroelectric liquid crystal (FLC) element can comprise a pair of conductive substrates, a FLC layer having a helical pitch and positioned between the conductive substrates, one or more spacers fixedly positioned between the conductive substrates, and an alignment layer positioned between the FLC layer and one of the conductive substrates. The alignment layer can be disposed at least partially contiguous with the FLC layer. The FLC layer can comprise a chiral smectic C* liquid crystal layer having at least one of a helical pitch smaller than an average cell gap of the FLC layer, or an average helical pitch of the FLC layer being smaller than an average thickness of the FLC layer between the conductive substrates.
    Type: Application
    Filed: September 10, 2021
    Publication date: August 3, 2023
    Inventors: Zhibo Sun, Zhengnan Yuan, Abhishek Kumar Srivastava, Hoi-Sing Kwok
  • Publication number: 20210063841
    Abstract: Techniques for using ferroelectric liquid crystals Dammann grating (FLCDG) for light detection and ranging devices are disclosed. In LiDAR devices, accuracy, response time, and cost performance can be limited by some factors, such as laser pulse width, time resolution of a time-to-digital conversion chip, detector bandwidth, shot noise, and time error generated by electronic circuits. A FLCDG-based architecture can improve a LiDAR device, and provide for one-shot capturing due to the high switching speed at very low driving voltage provided by ferroelectric liquid crystals and the equal diffracting ability of Dammann grating.
    Type: Application
    Filed: August 27, 2020
    Publication date: March 4, 2021
    Inventors: Zhengnan Yuan, Abhishek Kumar Srivastava, Zhibo Sun, Hoi Sing Kwok
  • Publication number: 20200402783
    Abstract: The present invention provides a novel partial-pressure mass spectrometer calibration device, which is mainly composed of a fine adjustment valve, a piston pressure gauge, a sample preparation chamber, a plurality of high-purity gas cylinders, a capacitive film vacuum gauge, a first-stage sample inlet chamber, a second-stage sample inlet chamber, sampling chambers, a small hole, a calibration chamber, a separation gauge and air pumping systems, wherein the sample preparation chamber is connected with the piston pressure gauge and the capacitive film vacuum gauge; the sample preparation chamber is also connected with the plurality of high-purity gas cylinders which are connected in parallel via the fine adjustment valve; a plurality of sampling chambers with different volumes are connected in parallel between the sample preparation chamber and the first-stage sample inlet chamber; a plurality of sampling chambers with different volumes are connected in parallel between the first-stage sample inlet chamber and
    Type: Application
    Filed: May 29, 2020
    Publication date: December 24, 2020
    Inventors: Detian LI, Wenjun SUN, Yongjun CHENG, Zhenhua XI, Zhengnan YUAN, Lan ZHAO, Meng DONG, Meiru GUO