Method of cleaning the reflector mirror in an optical dew point meter and an optical dew point meter equipped with a cleaning device
US5470154A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 1, 1994 |
| Grant date | Nov 28, 1995 |
| Priority date | — |
| Expiry date | Sep 1, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N25/68
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method of cleaning a reflector mirror in an optical dew point meter that measures the dew point or frost point of a sample gas by a process including the steps of bringing the sample gas into contact with the reflector mirror whose temperature is variable, projecting condensed rays of light or laser light onto said reflector mirror, and detecting the change in the intensity of scattered light and/or reflected light on account of the dew or frost formed on said reflector mirror, characterized by bringing a CO.sub.2 gas or a CO.sub.2 containing gas into contact with the reflector while the latter is in a cooled state, thereby condensing CO.sub.2 on the surface of the reflector mirror, and the subsequent step of heating the reflector mirror to vaporize the CO.sub.2 is dischosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.