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:
Dec. 22, 1981
Filed:
Nov. 05, 1979
Jacob van den Berg, Eindhoven, NL;
Rolf Schmidt, Roetgen-Rott, DE;
U.S. Philips Corporation, New York, NY (US);
Abstract
The invention relates to a method of determining variations in the previously adjusted nominal distance between the facing surfaces of a color selection electrode and a display window of a color television display tube in places situated near the corners of the display window. In this method the capacitance variations in that distance are determined by measuring a capacitor one electrode of which is formed by the color selection electrode and the other electrode is formed by a measuring electrode surrounded by a screening electrode, the measuring electrode being provided on the outer surface of the display window. By eccentrically moving the measuring electrode in a direction towards the corner of the display window relative to the screening electrode and by a suitable choice of the outside dimensions of the screening electrode, capacitance variations as a result of glass thickness variations in the display window are made negligibly small with respect to the capacitance variations due to variations in the previously adjusted nominal distance between the facing surfaces of the color selection electrode and the display window.