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:
Jul. 10, 1984
Filed:
Jul. 01, 1982
Applicant:
Inventor:
Frank W Ingle, Palo Alto, CA (US);
Assignee:
Medasonics, Inc., Mountain View, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
A61B / ; G01D / ;
U.S. Cl.
CPC ...
73 / ; 128688 ;
Abstract
An apparatus for calibrating a photoplethysmograph system comprising a white card mounted in the cone of a speaker. The card is mounted a predetermined distance from a photoplethysmograph sensor for providing an output from the sensor corresponding to the DC or venous mode. An oscillation is provided for oscillating the white card at a frequency corresponding to the average heartbeat for producing on the output of the sensor a signal corresponding to an average heartbeat. By adjusting the gain of the photoplethysmograph apparatus to obtain a constant amplitude output from the system, a calibration signal is obtained.