Title:
WAVELENGTH MODULATION DISPERSION SPECTRUM APPARATUS BASED ON HETERODYNE PHASE-SENSITIVE DETECTION AND DETECTION METHOD
Document Type and Number:
WIPO Patent Application WO/2023/241336
Kind Code:
A1
Abstract:
A wavelength modulation dispersion spectrum apparatus based on heterodyne phase-sensitive detection, and a detection method, which apparatus and method belong to the technical field of semiconductor infrared dispersion spectrums. The apparatus comprises a light source module, a sideband excitation module, a detection module, a photoelectric signal frequency reduction module and a signal demodulation module, wherein the light source module is used for generating a laser with a preset central wavelength, and performing wavelength modulation on the laser; the sideband excitation module is configured to enable the laser to generate two optical sidebands with a preset frequency difference from the preset central wavelength; the detection module is configured to detect transmission light after the laser with the two optical sidebands passes through a gas to be subjected to measurement, so as to generate a beat frequency signal; the photoelectric signal frequency reduction module is configured to collect the beat frequency signal and perform frequency reduction processing; and the signal demodulation module is configured to demodulate the frequency beat signal which has been subjected to frequency reduction, and obtain a secondary harmonic signal by means of demodulation. The phase of a beat frequency signal is modulated by means of wavelength modulation, and a signal-to-noise ratio of a system is increased by means of secondary demodulation.
Inventors:
REN WEI (CN)
HU MENGYUAN (CN)
HU MENGYUAN (CN)
Application Number:
PCT/CN2023/096609
Publication Date:
December 21, 2023
Filing Date:
May 26, 2023
Export Citation:
Assignee:
SHENZHEN RESEARCH INSTITUTE THE CHINESE UNIV OF HONG KONG (CN)
International Classes:
G01N21/01; G01N21/39
Foreign References:
| CN115144367A | 2022-10-04 | |||
| CN111380834A | 2020-07-07 | |||
| CN111721732A | 2020-09-29 | |||
| CN114136921A | 2022-03-04 | |||
| JP2018032822A | 2018-03-01 | |||
| US20210025689A1 | 2021-01-28 | |||
| US5111468A | 1992-05-05 |
Attorney, Agent or Firm:
SHENZHEN ZHONGYI UNION INTELLECTUAL PROPERTY AGENCY CO.,LTD. (CN)
Download PDF: