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:
Aug. 01, 1978
Filed:
Feb. 22, 1977
Dale G Maeding, Carlsbad, CA (US);
Hughes Aircraft Company, Culver City, CA (US);
Abstract
Signal charges in two charge coupled device (CCD) registers are subtracted one from the other by alternately passing them under a common, periodically clamped, normally floating sensing electrode. During those periods when the electrode is clamped, charge is shifted from the subtrahend register to the substrate region underlying the sensing electrode and charge, which has been shifted there previously from the minuend register, is shifted out of that region. During the intervening time periods, when the sensing electrode floats, the process is reversed, with charge from the minuend register being shifted under the sensing electrode and charge previously shifted there from the subtrahend register being shifted out. The resulting voltage reached by the sensing electrode during its floating intervals represents the difference between the charges in the two registers.