Quantitative analyses of biological tissue using phase modulation spectroscopy
US6263221A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 13, 1997 |
| Grant date | Jul 17, 2001 |
| Priority date | — |
| Expiry date | Feb 13, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2201/0696
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A spectroscopic system for quantifying in vivo concentration of an absorptive pigment in biological tissue includes an oscillator for generating a first carrier waveform of a first frequency on the order of 10.sup.8 Hz, a light source for generating light of a selected wavelengths modulated by the carrier waveform, and a detector for detecting radiation that has migrated over photon migration paths in the tissue from an input port to a detection port spaced several centimeters apart. The wavelength is sensitive to concentration of an absorptive pigment present in the tissue. A phase detector compares the detected radiation with the introduced radiation and determines therefrom the phase shift of the detected radiation. A processor quantifies the concentration of the absorptive pigment by calculating a value of the absorption coefficient.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.