METHOD FOR MANUFACTURING PROJECTION CATHODE RAY TUBE

Abstract

A vicinity part of a high-voltage feeding anode terminal, embedded in a funnel part and having a part thereof exposed on an outer wall surface of the funnel part, is washed with a hydrofluoric acid solution to remove a moisture-absorptive deposited substance adhering to the outer wall surface. According to a manufacturing method of this invention, anode leak failure due to unwanted discharge of the vicinity part of the high-voltage feeding anode can be restrained, and a projection cathode ray tube having an excellent display characteristic can be provided.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a schematic plan view showing an exemplary projection cathode ray tube device manufactured by a manufacturing method of this invention, as viewed from the rear side of the projection cathode ray tube device.

FIG. 1B is a sectional view showing essential parts of FIG. 1A.

FIG. 2 is a schematic sectional view showing essential parts of the projection cathode ray tube shown in FIGS. 1A and 1B.

FIG. 3 is a schematic front view of a vertical setting for explaining a method for manufacturing a projection cathode ray tube of this invention.

FIG. 4 is a schematic front view of a horizontal setting for explaining a method for manufacturing a projection cathode ray tube valve according to this invention.

FIG. 5 is a schematic sectional view for explaining an exemplary structure of a projection cathode ray tube device.

FIG. 6 is a schematic plan view for explaining an exemplary reproduction system of a projection display device.

FIG. 7 is a schematic sectional view showing an example of a conventional liquid-cooling projection cathode ray tube valve.

FIG. 8 is a schematic plan view showing a part of the appearance of FIG. 7.

Claims

1. A method of manufacturing a projection cathode ray tube comprising a evacuated envelope that includes a panel, a neck, and a funnel connecting the panel with the neck, the method including the step of washing a vicinity part of an anode terminal on an outer wall surface of the funnel with a hydrofluoric acid solution, the anode terminal being embedded in the funnel.

2. The method of manufacturing a projection cathode ray tube according to claim 1, wherein an exterior conductive film is formed after the step of washing the outer wall surface of the funnel with the hydrofluoric acid solution.