Patents by Inventor Wei-Chang Li

Wei-Chang Li 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: 11634319
    Abstract: A surface monitoring device is for monitoring a contact surface of a detected object. The surface monitoring device and the detected object are disposed on a substrate. The surface monitoring device includes a resonant mechanical part, having a contact tip adjacent to the contact surface by a preset gap in a static state. A driving circuit, applying an AC input signal to drive the resonant mechanical part to cause the contact tip to vibrate with respect to the contact surface at a plurality of sampling frequencies. The contact tip substantially hits the contact surface in a tapping bandwidth within the sampling frequencies. An analysis circuit to analyze a ratio of an output voltage to an input voltage of the input signal and determine the tapping bandwidth, wherein the ratio in the tapping bandwidth is jumping to a flatten phase.
    Type: Grant
    Filed: December 7, 2020
    Date of Patent: April 25, 2023
    Assignee: National Taiwan University
    Inventors: Wei-Chang Li, Chun-Pu Tsai, Hsuan-Wei Wang
  • Publication number: 20220002148
    Abstract: A surface monitoring device is for monitoring a contact surface of a detected object. The surface monitoring device and the detected object are disposed on a substrate. The surface monitoring device includes a resonant mechanical part, having a contact tip adjacent to the contact surface by a preset gap in a static state. A driving circuit, applying an AC input signal to drive the resonant mechanical part to cause the contact tip to vibrate with respect to the contact surface at a plurality of sampling frequencies. The contact tip substantially hits the contact surface in a tapping bandwidth within the sampling frequencies. An analysis circuit to analyze a ratio of an output voltage to an input voltage of the input signal and determine the tapping bandwidth, wherein the ratio in the tapping bandwidth is jumping to a flatten phase.
    Type: Application
    Filed: December 7, 2020
    Publication date: January 6, 2022
    Applicant: National Taiwan University
    Inventors: Wei-Chang Li, Chun-Pu Tsai, Hsuan-Wei Wang
  • Patent number: 10257002
    Abstract: A microelectromechanical resonant switch (“resoswitch”) converts received radio frequency (RF) energy into an output signal with zero quiescent power usage by using a resonant element with a passband input sensitivity of: <?60 dBm, <?68 dBm, and <?100 dBm. The resoswitch first accepts incoming amplitude- or frequency-shift keyed RF energy at a carrier frequency, filters it, provides power gain via resonant impact switching, and finally envelop detects impact impulses to demodulate and recover the modulating waveform. Mechanical gain may be used to amplify received signals, whose amplitudes may be binned, thereby preserving use of amplitude modulated (AM) signals. A second resoswitch may be used to control additional circuitry, whereby the first resoswitch detects a control signal output to the additional circuitry.
    Type: Grant
    Filed: June 19, 2017
    Date of Patent: April 9, 2019
    Assignee: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Clark T.-C. Nguyen, Wei-Chang Li, Ruonan Liu
  • Publication number: 20180145853
    Abstract: A microelectromechanical resonant switch (“resoswitch”) converts received radio frequency (RF) energy into an output signal with zero quiescent power usage by using a resonant element with a passband input sensitivity of: <?60 dBm, <?68 dBm, and <?100 dBm. The resoswitch first accepts incoming amplitude- or frequency-shift keyed RF energy at a carrier frequency, filters it, provides power gain via resonant impact switching, and finally envelop detects impact impulses to demodulate and recover the modulating waveform. Mechanical gain may be used to amplify received signals, whose amplitudes may be binned, thereby preserving use of amplitude modulated (AM) signals. A second resoswitch may be used to control additional circuitry, whereby the first resoswitch detects a control signal output to the additional circuitry.
    Type: Application
    Filed: June 19, 2017
    Publication date: May 24, 2018
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Clark T.-C. Nguyen, Wei-Chang Li, Ruonan Liu
  • Patent number: 9077060
    Abstract: A modally driven oscillating element periodically contacts one of more electrical contacts, thereby acting as a switch, otherwise known as a resonant switch, or “resoswitch”, with very high Q's, typically above 10000 in air, and higher in vacuum. Due to periodic constrained contacting of the contacts, the bandwidth of the switch is greatly improved. One or more oscillating elements may be vibrationally interconnected with conductive or nonconductive coupling elements, whereby increased bandwidths of such an overall switching system may be achieved. Using the resoswitch, power amplifiers and converters more closely approaching ideal may be implemented. Integrated circuit fabrication techniques may construct the resoswitch with other integrated CMOS elements for highly compact switching devices. Through introduction of specific geometries within the oscillating elements, displacement gains may be made where modal deflections are greatly increased, thereby reducing device drive voltages to 2.5 V or lower.
    Type: Grant
    Filed: September 9, 2010
    Date of Patent: July 7, 2015
    Assignee: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Clark Tu-Cuong Nguyen, Yang Lin, Wei-Chang Li, Bongsang Kim
  • Publication number: 20110067984
    Abstract: A modally driven oscillating element periodically contacts one of more electrical contacts, thereby acting as a switch, otherwise known as a resonant switch, or “resoswitch”, with very high Q's, typically above 10000 in air, and higher in vacuum. Due to periodic constrained contacting of the contacts, the bandwidth of the switch is greatly improved. One or more oscillating elements may be vibrationally interconnected with conductive or nonconductive coupling elements, whereby increased bandwidths of such an overall switching system may be achieved. Using the resoswitch, power amplifiers and converters more closely approaching ideal may be implemented. Integrated circuit fabrication techniques may construct the resoswitch with other integrated CMOS elements for highly compact switching devices. Through introduction of specific geometries within the oscillating elements, displacement gains may be made where modal deflections are greatly increased, thereby reducing device drive voltages to 2.5 V or lower.
    Type: Application
    Filed: September 9, 2010
    Publication date: March 24, 2011
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Clark Tu-Cuong Nguyen, Yang Lin, Wei-Chang Li, Bongsang Kim