Multiplex coherent raman spectroscopy detector and method
US6747735B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 13, 2003 |
| Grant date | Jun 8, 2004 |
| Priority date | — |
| Expiry date | Jun 13, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/655
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A multiplex coherent Raman spectrometer (10) and spectroscopy method rapidly detects and identifies individual components of a chemical mixture separated by a separation technique, such as gas chromatography. The spectrometer (10) and method accurately identify a variety of compounds because they produce the entire gas phase vibrational Raman spectrum of the unknown gas. This is accomplished by tilting a Raman cell (20) to produce a high-intensity, backward-stimulated, coherent Raman beam of 683 nm, which drives a degenerate optical parametric oscillator (28) to produce a broadband beam of 1100-1700 nm covering a range of more than 3000 wavenumber. This broadband beam is combined with a narrowband beam of 532 nm having a bandwidth of 0.003 wavenumbers and focused into a heated windowless cell (38) that receives gases separated by a gas chromatograph (40). The Raman radiation scattered from these gases is filtered and sent to a monochromator (50) with multichannel detection.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.