Method and apparatus for determining the concentration of a target gas using an optical gas sensor system
US6096560A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 24, 1998 |
| Grant date | Aug 1, 2000 |
| Priority date | — |
| Expiry date | Nov 24, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T436/205831
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The concentration of a target gas is determined in an optical gas sensor system having an array of optical gas sensors wherein each sensor has a different sensitivity range for a target gas. An active sensor is selected from the array of optical gas sensors by determining which sensor has an optical transmittance value between 0% and 100%. Optical transmittance values of the active sensor are differentiated with respect to time. Concentration of the target gas is calculated as a function of both the rate of change of optical transmittance and the value of the optical transmittance at the beginning of the period over which the transmittance is differentiated. When a hazardous gas such as carbon monoxide is the target gas an alarm can be given when a threshold concentration is exceeded. Preferably, the transmittance values are converted to digital signals and processed in an eight-bit microprocessor to determine target gas concentration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.