Patent · US Expired

Non-invasive oximeter arrangement

US5279295A · kind A · utility

221Cited by

7References

17Claims

0Family size

Assignee

U.S. Philips Corporation · US

Inventors

Gerhard Martens · Henstedt-Ulzburg, DE
Jurgen Kordts · Wedel, DE
Thomas Helzel · Kaltenkirchen, DE

Key dates

Filing date	Nov 20, 1990
Grant date	Jan 18, 1994
Priority date	—
Expiry date	Nov 20, 2010

Classification

Technology area (CPC A)Human Necessities
CPC primaryA61B5/7207
WIPO fieldMedical technology
WIPO sectorInstruments

Abstract

A sensor includes a pair of resiliently loaded jaws for receiving a finger, the sensor including a pair of fiber optic light transmitting guides secured in fixed spaced relation to one of the jaws for sensing blood in the finger tip. A control unit includes a light generator for transmitting light modulated at first and second frequencies to one of the guides via a light guide transfer section. The finger pulse modulates the received transmitted light. The modulated light is sensed by the other guide and returned to a receiver in the control unit via the transfer section for separating and demodulating the different frequency signals. The control unit includes a calculating unit which has two branches for processing and then combining by dividing the processed demodulated signals for determining the oxygen content of the blood from the relative magnitudes of the pulse-dependent modulation factor of the wave reflected from the finger.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.