Apparatus and method for the identification of gases
US5070245A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 2, 1989 |
| Grant date | Dec 3, 1991 |
| Priority date | — |
| Expiry date | Nov 2, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/3504
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus and method for the identification of one or more anesthetic or other gases included in the respiratory air of a patient, said identification being effected within the infrared range 3-4 .mu.m. The appratus comprises a radiation source (4), a chamber (1) for receiving therein a gas or gases to be examined, an optical filter (7) for passing the radiation exiting the chamber therethrough, an optical focusing device (12) through or via which the incoming radiation travels, a radiation detector (10) and a measuring processor (19) which performs the measuring and identification. The transmission band of the optical filter (7) or a combination of successive filters is within a range of 1.5%-0.4% of the mean transmission wavelength and the ray arriving at filter (7) has an angle of incidence between 10.degree.-60.degree., the measuring effected within this range being performed at more than two angles. A measured spectrum is compared with a prior known spectrum by means of correlation algorithm to carry out the ientification. In a monitor for anesthetic gases, the content of gases is measured by means of a rapid-response sensor breath by breath. The quality or mixing ratio of …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.