Method for coating a selected portion of the internal neck surface of a CRT
AssigneeRCA Corporation
InventorKarl G. Hernqvist
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Abstract
A method for coating a selected portion of the internal surface of the neck of a CRT having a beaded electron-gun mount assembly housed therein. The method comprises providing in the neck at least one source of chromium metal spaced from and within line-of-sight of at least a portion of the neck surface opposite each bead. The CRT is evacuated to a low gas pressure and then chromium metal vapor is released from each source towards the neck surface, whereby chromium metal deposits on the neck surface.
Claims9
A method for coating a selected portion of the internal surface of the neck of a CRT, said neck housing an electron-gun assembly including at least two electrically-insulating support rods, each of said rods having a rod surface that is opposite and closely spaced from said internal neck surface, each of said rod surfaces and the rod-opposed neck surface that is opposite thereto defining a bead channel, said method comprising
- (a) providing in said neck at least one source of chromium metal for each of said bead channels, each source being spaced from and within line-of-sight of at least a portion of the rod-opposed neck surface defining said channel,
- (b) evacuating said CRT to a low gas pressure,
- (c) and then releasing chromium metal vapor from said source into said bead channel towards said rod-opposed neck surface;
- whereby chromium metal deposits as a layer on said rod-opposed neck surface.
Dependencies are inferred from the claim text.