The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 23, 2025
Filed:
Jun. 30, 2022
The Chinese University of Hong Kong, Hong Kong, CN;
The Chinese University of Hong Kong, Hong Kong, CN;
Abstract
A passive-phase-detection photothermal spectroscopy (PTS) system and methods are provided for gas measurements. The PTS system includes a pump laser source, a probe laser source, the pump and probe laser beams simultaneously propagating through an optical waveguide having a target gas specimen. Moreover, the PTS system can be based on a heterodyne detection scheme and includes a combiner configured to align light input from a local oscillator with the probe laser beam output from the optical waveguide to output to a photodetector that is configured to generate beat notes. A lock-in phase detector and a lock-in amplitude detector is configured to detect and measure a photothermal signal based on the beat notes received from the photodetector for gas measurements. The PTS system can also be based on a core-cladding-mode interference detection scheme and generates the core mode and cladding mode simultaneously for the probe laser in the waveguide.