Blood glucose monitor
US4704029A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 26, 1985 |
| Grant date | Nov 3, 1987 |
| Priority date | — |
| Expiry date | Dec 26, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T436/144444
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A blood glucose monitor which is particularly applicable for use as an implant for controlling an insulin pump, or as a portable device for use by a diabetic for home blood glucose monitoring. The glucose monitor measures the glucose level of blood by utilizing a refractometer which measures the index of refraction of blood adjacent to an interface with a transparent surface of the refractometer, by directing light at the interface to measure the index of refraction of the blood by the amount of radiation reflected by the interface, particularly light incident near the critical angle. In a preferred embodiment, polarized light is directed against an interface in an implant between a transparent material and the blood. As the glucose concentration in the blood changes, its index of refraction changes, as does the intensity of light reflected from the interface. The angle of incidence of the light is selected to be slightly less than the critical angle for total internal reflection, with the result that the reflected intensity varies dramatically with index of refraction and with glucose concentration. A differential amplifier compares the intensity of the light reflected from the bl…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.