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. 06, 1987
Filed:
Mar. 25, 1986
Applicant:
Inventors:
Gerald W Jones, Johnson City, NY (US);
W Robert Pratt, Binghamton, NY (US);
William J Summa, Endwell, NY (US);
Assignee:
IBM Corporation, Armonk, NY (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01N / ;
U.S. Cl.
CPC ...
356239 ; 356 51 ; 361411 ;
Abstract
A method is disclosed for the visual inspection of electrical circuitry deposited in the layers of a multilayer printed circuit board wherein the dielectric layers of the multilayer board are prepared using a clear, light transparent thermosetting resin having incorporated therein a dye which is permeable to visible light but which absorbs light in the 320-440 nm region. The electrical circuitry in the board can be easily traced by an observer upon illumination of the board by visible light.