Method and apparatus for optical spectroscopy incorporating a vertical cavity surface emitting laser (VCSEL) as an interferometer reference
US6654125B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 4, 2002 |
| Grant date | Nov 25, 2003 |
| Priority date | — |
| Expiry date | Apr 4, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J3/453
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A vertical cavity surface-emitting laser (VCSEL) package utilized as a laser reference for use in interferometry. The primary disadvantage of VCSELs, in terms of interferometry, has been found to be the relatively poor wavenumber stability of the beam. The present invention is a method and apparatus that makes viable a VCSEL package suitable for use as a reference in interferometry. The VCSEL package incorporates current control, temperature control and an algorithm for correcting wavenumber drift. The algorithm is derived from spectroscopic analysis of a reference sample having a known spectrum and comparing the generated spectrum to the known spectrum.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.