Spectrometer system for optical reflectance measurements
US7245373B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Apr 25, 2005 |
| Grant date | Jul 17, 2007 |
| Priority date | — |
| Expiry date | Sep 18, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2201/08
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A spectrometer system includes a thermal light source for illuminating a sample, where the thermal light source includes a filament that emits light when heated. The system additionally includes a spectrograph for measuring a light spectrum from the sample and an electrical circuit for supplying electrical current to the filament to heat the filament and for controlling a resistance of the filament. The electrical circuit includes a power supply that supplies current to the filament, first electrical components that sense a current through the filament, second electrical components that sense a voltage drop across the filament, third electrical components that compare a ratio of the sensed voltage drop and the sensed current with a predetermined value, and fourth electrical components that control the current through the filament or the voltage drop across the filament to cause the ratio to equal substantially the predetermined value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.