发明名称 |
Portable remote laser sensor for methane leak detection |
摘要 |
A portable laser system for remote detection of methane gas leaks and concentrations is disclosed. The system transmitter includes first and second lasers, tuned respectively to a wavelength coincident with a strong absorption line of methane and a reference wavelength which is weakly absorbed by methane gas. The lasers are aimed at a topographical target along a system axis and the beams successively interrupted by a chopper wheel. The system receiver includes a spherical mirror for collecting the reflected laser radiation and focusing the collected radiation through a narrowband optical filter onto an optial detector. The filter is tuned to the wavelength of the two lasers, and rejects background noise to substantially improve the signal-to-noise ratio of the detector. The output of the optical detector is processed by a lock-in detector synchronized to the chopper, and which measures the difference between the first wavelength signal and the reference wavelength signal.
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申请公布号 |
US4489239(A) |
申请公布日期 |
1984.12.18 |
申请号 |
US19820423016 |
申请日期 |
1982.09.24 |
申请人 |
THE UNITED STATES OF AMERICA AS REPRESENTED BY THE ADMINISTRATOR OF THE NATIONAL AERONAUTICS AND SPACE ADMINISTRATION |
发明人 |
GRANT, WILLIAM B.;HINKLEY, JR., E. DAVID |
分类号 |
G01J1/44;G01N21/31;G01N21/39;(IPC1-7):G01J1/00 |
主分类号 |
G01J1/44 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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