Gas analysis system having buffer gas inputs to protect associated optical elements
US5153671A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 11, 1990 |
| Grant date | Oct 6, 1992 |
| Priority date | — |
| Expiry date | May 11, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/8578
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A gas analysis cell positioned within an optical resonant cavity in a gas analysis system is disclosed wherein the cell includes a flow of buffer gas which forms a "dam", thereby protecting the optical elements in the analysis system. The analysis cell includes an inlet for introducing a gas sample into the analysis chamber of the cell. Two buffer gas inlet ports, one on each end of the cell, are provided to introduce a flow of buffer gas which is directed past optical elements in the system adjacent the ends of the cell. Two output ports are located at the ends of the analysis chamber to remove the buffer gas and gas sample mixture. The flow of buffer gas acts to confine the gas sample within the analysis chamber and reduce adverse effects which occur when the gas sample comes in contact with the optical elements of the system. By providing a constant non-turbulent flow of gas adjacent the system optics, adverse changes in index of refraction are avoided, thus reducing beam steering and Schlieren effects which can occur when Brewster windows or other optics are used to constrain the gas sample within the analysis cell. The buffer gas flow in the analysis cell of the present invent…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.