Apparatus and method of remote gas trace detection
US6518562B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 13, 2001 |
| Grant date | Feb 11, 2003 |
| Priority date | — |
| Expiry date | Mar 13, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/1793
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
This specification discloses a method and apparatus for the mobile and remote detection of a gas, such as methane, in the atmosphere. The apparatus includes a TDL based Light Detection and Ranging (LIDAR) driven at carrier frequency lying within the absorption line of the gas. The apparatus also drives the TDL with a modulation frequency to generate upper and lower sidebands in the output of the TDL and with a low ramp frequency to sweep the output of the TDL across twice the width of the pressure-broadened absorption line of the gas, preferably the first overtone absorption line in the case of methane detection. Suitable power for remote detection through use of the TDL is provided by a master oscillator/fiber amplifier transmitter has no moving or adjustable parts at all. An all-solid-state monolithic and integrated amplifier is achieved, which leads to a compact and virtually maintenance-free LIDAR system. The remote detection apparatus includes reference and calibration cells or chambers, and includes a light collector and detectors to detect the quantity and modulation of the light that passes the reference or calibration cells and that is received by the apparatus after refle…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.