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:
May. 10, 1994
Filed:
Jan. 21, 1993
Applicant:
Inventors:
David B Chang, Tustin, CA (US);
Slava A Pollack, Palos Verdes Estate, CA (US);
James Drummond, Oceanside, CA (US);
Michael F Berg, Indio Hills, CA (US);
Assignee:
Hughes Aircraft Company, Los Angeles, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01R / ; G01R / ; G02F / ;
U.S. Cl.
CPC ...
324501 ; 324530 ; 324537 ; 324 96 ; 3241 / ; 359 74 ; 359 84 ;
Abstract
A nondestructive noninvasive device and method for testing printed circuit boards (PCBs) through the utilization of a liquid crystal material which visually images the electric fields of the PCBs. Circuit faults resulting in a change of current flow in a PCB produce recognizable changes in observed electric fields. The present invention may be used in a stand-alone mode or as a supplement to other testing techniques.