Raman system for rapid sample indentification
US6483581B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 1999 |
| Grant date | Nov 19, 2002 |
| Priority date | — |
| Expiry date | Dec 22, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/656
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A hand-held material identification apparatus 10 uses a spectrograph and detector array detecting a Raman spectrum produced by a sample illuminated by a laser source to recognize a variety of materials with a command to recognition time cycle of about one second or less. The width of the spectrum detected by each detector in the array is less than ¼th the excitation source wavelength deviation to permit smoothing of the spectrum detected by the discrete spectral elements to eliminate pixel noise without loss of Raman spectral information. The Raman spectra are produced by materials illuminated by an inexpensive near-infrared multimode laser operated in a pulse mode to deliver between 0.05 and 0.5 joules of photon energy, with the Raman spectra being detected before any significant heating of the sample occurs. The identification apparatus 10 qualitatively determines the chemical composition of reinforced and unreinforced copolymers and composites such as ABS, polypropylene, talc-filled polypropylene, polycarbonate, PMMA, polyethylene, and PVC, from samples of different colors and textures with a high degree of success without the need for special positioning or sample prepar…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.