Pump-probe photothermal spectroscopy having passive phase detection and an optical waveguide
US12422351B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 2022 |
| Grant date | Sep 23, 2025 |
| Priority date | — |
| Expiry date | Jun 30, 2042 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/458
- WIPO fieldMeasurement
- WIPO sectorInstruments
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.