Device for optical monitoring of constituent in tissue or body fluid sample using wavelength modulation spectroscopy, such as for blood glucose levels
US7356364B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 21, 2005 |
| Grant date | Apr 8, 2008 |
| Priority date | — |
| Expiry date | Sep 11, 2026 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B5/7239
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A device for monitoring the concentration level of a constituent in tissue or a body fluid sample, such as glucose concentration in blood, has a laser light source which is modulated about a center emission frequency to probe the absorption spectrum of the constituent being monitored, a laser driver circuit for tuning and modulating the laser light, a photodetector for detecting light from the laser light source transmitted through the sample as the modulation frequency of the laser is tuned, and a demodulator for demodulating the transmitted light and detecting variations in magnitude at harmonics of the modulation frequency to assess the concentration level of that constituent. The device utilizes short-wavelength near-infrared laser light to monitor blood glucose levels, and could also be used for drug screening and diagnosis of other medical conditions as well. In one embodiment, the device is used to monitor blood glucose level externally from the body and non-invasively by trans-illumination through a thin layer of skin, without the need for physical penetration of the skin. In another embodiment, the device is used as an intravenous sensor deployed through a catheter, and it…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.