Optical measurement system for spectral analysis
US4433238A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 19, 1981 |
| Grant date | Feb 21, 1984 |
| Priority date | — |
| Expiry date | Oct 19, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L11/02
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The invention relates to an optical measuring device for measuring physical or chemical quantities which device employs at least one light source, such as a light-emitting diode, in optical connection with a sensor, the spectral properties of which (e.g. the absorption or luminescence spectrum) are adapted to be changed by the quantity being measured, and at least one light detector (e.g. a photo-diode or a photo-transistor) for receiving the output signal from the sensor. The invention is characterized in that the measuring signal is adapted to be obtained by spectral analysis, and that this spectral analysis is adapted to be performed by varying the spectral distribution of the light source (the light-emitting diode) or maintaining said distribution constant, and/or by varying the sensitivity spectrum of the light detector or maintaining said spectrum constant, and that this control of the emission spectrum and the sensitivity spectrum is adapted to be carried out by a periodic controlling of the temperature of the light source and of the light detector, respectively.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.