Method of vapor depositing an interference filter layer on the inside of a display window, a display window, a projection cathode ray tube and a projection television apparatus

Abstract

Method of vapor-depositing an interference filter layer on the inside of a display window, a display window, a projection cathode ray tube and a projection television apparatus. A method of manufacturing a projection cathode ray tube comprising an interference filter on an inwardly directed surface of a display window, the method comprising as a process step the vapor deposition of at least one layer of the interference filter. It has been found that the edges of a display window during the vapor deposition of an interference filter layer detrimentally influence the thickness of the vapor deposited layer, the thickness increases more towards the edges than follows from geometrical computations. In the method according to the invention vapor deposition is performed on a display window for which the height of the edge is less than 1/5 of the minor axis. The display screen preferably comprises a recessive edge.

Dependencies are inferred from the claim text.