Method of determining masses of absorbing components of a sample in a test volume and a device for implementation of this method
US4577105A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Apr 20, 1984 |
| Grant date | Mar 18, 1986 |
| Priority date | — |
| Expiry date | Apr 20, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/534
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A test volume and a reference volume are irradiated by separate beams of an infrared source, and the two beams are subsequently fed to a detector in periodical alternation. The time constant of the detector is small compared to the period of this alternation. From the measured differences in intensity the masses of the absorbing components of a sample in the test volume are determined. During each period the value of the detector signal is sampled by an evaluation unit at least once while either the test beam or the reference beam is being present at the detector. For separate determination of different sample components, radiation of different defined frequency bands is fed to the detector during each period, and the intensity of the test beam is determined at each of the different frequencies whereas that of the reference beam is determined at one of these frequencies at least.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.