Optoacoustic gas sensor
US6006585A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 22, 1998 |
| Grant date | Dec 28, 1999 |
| Priority date | — |
| Expiry date | Jan 22, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/02872
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In an optoacoustic gas sensor having a sensor body (1, 2), a light source (10), a measurement cell (6) with a gas-permeable membrane (15), a measurement microphone (13), and an optical measurement filter (11) between the light source (10) and the measurement cell (6), a reference cell (7) is included that is separate from the measurement cell (6). The reference cell (7) has a reference microphone (14) that is shielded against optoacoustic signals from the gas to be detected via the reference cell being substantially free from intensity-modulated optical radiation having an absorption wavelength of the gas to be detected. The measurement signal, which indicates gas concentration, is obtained by subtraction of the signals from the two microphones (13, 14).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.