Patent · US Expired

Pulse oximetry

US5431159A · kind A · utility

159Cited by
15References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 17, 1991
Grant dateJul 11, 1995
Priority date
Expiry dateJun 17, 2011

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61B5/14551
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

Non-invasive oximetry wherein red and infrared light from light sources energized at different frequencies is applied to arterial blood-containing tissue of a living subject. The red and infrared light coming from this tissue is sensed in order to obtain frequency-muliplexed information as to the absorption of said light by said tissue, the information being processed in order to derive therefrom a measure of percent oxygen saturation of said blood. The processing includes filtering for separating information represented by red light absorption from information represented by infrared light absorption. In particular, both notch and bandpass filters are used, and AM detectors provide for further separating such information into DC and AC components.

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