Sensing device for detecting the presence of a gas contained in a mixture thereof
US4495793A · kind A · utility
17Cited by
2References
15Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Aug 30, 1982 |
| Grant date | Jan 29, 1985 |
| Priority date | — |
| Expiry date | Aug 30, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/12
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sensing device which senses the presence and/or concentration of one or more gases contained in a mixture is disclosed. An electrically charged semiconductor whose surface is in contact with the mixture of gases is illuminated with light, either intermittently or constantly. Changes in the transient and steady state conductivity of the semiconductor are measured and amplified. The form of the functionality between the gas and the conductivity changes is unique to a particular gas at a particular concentration and is used both to detect the presence and/or concentration of the gas.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.