Carl A Barlow

US Patent:

43389503, Jul 13, 1982

Filed:

Sep 22, 1980

Appl. No.:

6/189400

Inventors:

Carl A. Barlow - Plano TX
Lee R. Reid - Plano TX

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

A61B 502

US Classification:

128687

Abstract:

An improved system and method for sensing and measuring heart beat. A body-mountable instrument is provided having a first sensor for detecting pulsing of a user's blood resulting from the user's heart beat and body movement and generating a first electrical signal indicative thereof and a second sensor for detecting the user's body movement and generating a second electrical signal indicative thereof. The instrument further includes a processor responsive to the first and second electrical signals for determining the period of the second electrical signal and for subtracting a first portion of the first electrical signal occurring during a first time interval from a corresponding portion of the first electrical signal occurring during a second time interval. The second time interval is separated from the first time interval by a time period nt, where n is an integer and t is the period of the second electrical signal, so that the body movement component is removed from the first electrical signal, yielding the true heart beat signal.