Tracer to compensate for environmental variations that influence a chemical vapor sensor measurement
US7736903B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 5, 2005 |
| Grant date | Jun 15, 2010 |
| Priority date | — |
| Expiry date | Dec 8, 2028 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T436/204165
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A chemical vapor sensor is provided that passively measures a suspect chemical species of interest with high sensitivity and chemical specificity, for use with safety systems. A vapor concentrator amplifies a suspect chemical vapor concentration to a detectible level, for use with an infrared detector. Compensation is provided for environmental variations that may influence the passive measurement of the chemical vapor sensor. Environmental variations may include extrinsic vapors in the surrounding air, or air currents that divert the sample vapor as it drifts from the suspect vapor source to a sampling intake. In an example, ethanol vapor is measured and carbon dioxide tracer measurements are used to calculate an ethanol vapor measurement that is adjusted for environmental variations. In an aspect, a time artifact filter sets the output of the carbon dioxide sensor to match the time dependence of the ethanol sensor, to calculate blood alcohol concentration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.