Patent · US Expired

Photoelectric oximeter

US3998550A · kind A · utility

206Cited by
3References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 10, 1975
Grant dateDec 21, 1976
Priority date
Expiry dateOct 10, 1995

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N21/314
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An optical non-invasive oximeter for measuring oxygen saturation in arterial blood utilizes a light source capable of giving off light having different wavelengths, such as light in the infrared and red region, and a pair of photoelectric devices, one responding to one wavelength and the other to the other wavelength, for detecting the amount of such light transmitted through living tissue. Each photoelectric device is connected to a computing circuit which generates a signal that represents the logarithm of the quotient of the signal received from the photoelectric device divided by its direct current component. The signals from each of the computing circuits are differentiated and then divided, one by the other, to provide an indication of oxygen saturation in the blood.

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