The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 18, 1994
Filed:
Nov. 20, 1990
Gerhard Martens, Henstedt-Ulzburg, DE;
Jurgen Kordts, Norderstedt, DE;
Thomas Helzel, Kaltenkirchen, DE;
U.S. Philips Corporation, New York, NY (US);
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.