Method for measurment and compensation of stray light in a spectrometer
US5801829A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 8, 1996 |
| Grant date | Sep 1, 1998 |
| Priority date | — |
| Expiry date | Feb 8, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J3/2803
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method of measuring and compensating the effects of stray light in a spectrometer and use of the method to improve linearity and accuracy in the spectrometer. Light from a broadband light source (100) is blocked in a particular band of wavelengths by an optical filter (104) and light outside the particular band of wavelengths is transmitted by the filter. A spectral measurement within the particular band measures aggregate offset, including the effects of stray light, dark current and electronic offset. In absorption spectrometry, a first spectral measurement within the particular band is measured with a chemical sample not present and a second measurement is made with a chemical sample present. The first spectral measurement is used for compensation of a reference spectrum and the second spectral measurement is used for compensation of a sample spectrum, each within the particular band. Further compensation is made for insertion loss of a filter and stray light having wavelengths within the band of wavelengths of the particular band.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.