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. 25, 2000
Filed:
Aug. 11, 1997
Kurt Albert Aronow, Lafayette, CO (US);
Datex-Ohmeda, Inc., Liberty Corner, NJ (US);
Abstract
An improved photoplethysmographic measurement system is disclosed in which a fast-turn-off photodiode is used in order to minimize the effect of 'bleed-through' voltages on the dark time (ambient) light determination. Particularly in photoplethysmographic instruments which utilize switched-gain preamplifiers the 'bleed-through' of voltage which should be associated with the excitation of the photodiode by the emitter into the dark time or ambient light calculation will negatively impact the accuracy of blood analyte determination. A hardware method and a software method for determining whether a given photodiode has a sufficient decay time are also disclosed.