Patents by Inventor Tomohiro Tetsumoto

Tomohiro Tetsumoto 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: 11409185
    Abstract: Systems and methods for precision control of microresonator (MR) based frequency combs can implement optimized MR actuators or MR modulators to control long-term locking of carrier envelope offset frequency, repetition rate, or resonance offset frequency of the MR. MR modulators can also be used for amplitude noise control. MR parameters can be locked to external reference frequencies such as a continuous wave laser or a microwave reference. MR parameters can be selected to reduce cross talk between the MR parameters, facilitating long-term locking. The MR can be locked to an external two wavelength delayed self-heterodyne interferometer for low noise microwave generation. An MR-based frequency comb can be tuned by a substantial fraction or more of the free spectral range (FSR) via a feedback control system. Scanning MR frequency combs can be applied to dead-zone free spectroscopy, multi-wavelength LIDAR, high precision optical clocks, or low phase noise microwave sources.
    Type: Grant
    Filed: April 7, 2021
    Date of Patent: August 9, 2022
    Assignee: IMRA America, Inc.
    Inventors: Naoya Kuse, Martin E. Fermann, Tomohiro Tetsumoto, Antoine Jean Gilbert Rolland
  • Publication number: 20220221583
    Abstract: A tunable millimeter-wave signal oscillator includes two phase coherent optical oscillators, a fiber-ring cavity configured to generate two Stokes waves, and a photosensitive element converting the frequency difference of two optical oscillator into a millimeter-wave radiation. A chip-scale form factor millimeter-wave oscillator includes two continuous wave lasers, a plurality of micro-optical-resonators, an optical frequency division mechanism, two optical tunable bandpass filters, and a photosensitive element converting the pulse train of a frequency comb into a millimeter-wave radiation. A millimeter-wave phase noise analyzer includes an optical interferometer, two photosensitive elements, and a fundamental millimeter-wave frequency mixer. A millimeter-wave frequency counter includes an electro-optic optical frequency comb generator, a microwave voltage controlled oscillator, and an optoelectronic phase locked loop.
    Type: Application
    Filed: April 7, 2021
    Publication date: July 14, 2022
    Inventors: Antoine Jean Gilbert Rolland, Eng Hiang Mark Yeo, Tomohiro Tetsumoto
  • Publication number: 20210294180
    Abstract: Systems and methods for precision control of microresonator (MR) based frequency combs can implement optimized MR actuators or MR modulators to control long-term locking of carrier envelope offset frequency, repetition rate, or resonance offset frequency of the MR. MR modulators can also be used for amplitude noise control. MR parameters can be locked to external reference frequencies such as a continuous wave laser or a microwave reference. MR parameters can be selected to reduce cross talk between the MR parameters, facilitating long-term locking. The MR can be locked to an external two wavelength delayed self-heterodyne interferometer for low noise microwave generation. An MR-based frequency comb can be tuned by a substantial fraction or more of the free spectral range (FSR) via a feedback control system. Scanning MR frequency combs can be applied to dead-zone free spectroscopy, multi-wavelength LIDAR, high precision optical clocks, or low phase noise microwave sources.
    Type: Application
    Filed: April 7, 2021
    Publication date: September 23, 2021
    Inventors: Naoya Kuse, Martin E. Fermann, Tomohiro Tetsumoto, Antoine Jean Gilbert Rolland