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:
Oct. 15, 1991
Filed:
May. 04, 1990
Applicant:
Inventor:
Henry P Hall, Concord, MA (US);
Assignee:
GenRad, Inc., Concord, MA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01R / ;
U.S. Cl.
CPC ...
3241 / ; 324 731 ;
Abstract
An AC signal source (26) in series with a variable DC source (34) drives a gate line of an LCD-display drive matrix (10), and current meters (28, 30, 32) monitor the resultant currents in the drain lines. By comparing the thus-measured transadmittance both with and without enabling values of the DC-source output, one can test the matrix (10) for defects.