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:
Feb. 05, 1991
Filed:
Nov. 22, 1989
Miroslav Ondris, Chagrin Falls, OH (US);
Allen A Endres, Chagrin Falls, OH (US);
Stemcor Corporation, Cleveland, OH (US);
Abstract
A method and means for the electronic processing of an analog signal generated in a series addressed diode array to produce a digital signal indicative of the illumination of the photodiodes in the array is disclosed. A voltage ramp is applied to the array and the resulting current steps converted to a voltage signal. The voltage signal is differentiated and the resulting pulses are digitized to provide the illumination state of the photodiodes in the array. Alternately, the voltage signal is integrated in a series of windows. The results of each previous integration is substrated from the most current integration, producing a series of pulses that are digitized to provide the illumination state of the array. The processing may be synchronized by either dividing the sweep interval into evenly spaced intervals, by differentiating the voltage signal and detecting the derivative exceeding a threshold, or differentiating the voltage signal twice and detecting zero-crossings in the resulting signal. The voltage ramp may be made to increase in slope with time to help ensure that the addressing diodes begin conducting at equal time intervals.