Method of manufacturing an electric discharge tube

DETAILED DESCRIPTION What is claimed is: 1.
A method of manufacturing an electric discharge tube of the type having, in an envelope composed of a first portion which is hermetically sealed to a second portion, a radiation sensitive layer on said first portion and a system of electrodes arranged opposite said radiation sensitive layer, comprising the steps of: forming said radiation sensitive layer on said first portion of the tube envelope in a first evacuated vessel which is temporarily closed by that first portion of the tube envelope using a liquid metal sealant of a gallium containing material, degassing the system of electrodes in a second evacuated vessel assembled of said second portion of the tube envelope and auxiliary closing member which are temporarily sealed together using a liquid metal sealant of said gallium containing material, filling said first and said second vessel with an inert gas at a pressure substantially equal to the ambient pressure on said vessels, disconnecting said first portion of the tube envelope from said first vessel and transporting said first portion to said second vessel, whereby the inert gas protects the radiation-sensitive layer on said first portion from exposure to the atmosphere during the transfer step, disconnecting the auxiliary closing member from said second vessel, sealing said first portion to said second portion of the tube envelope using a liquid metal sealant of said gallium containing material and evacuating the tube.
2.
The method of claim 1, wherein said first portion of the tube envelope is a glass plate member and said second portion of the tube envelope is a glass cylindrical bulb which is open at one end and closed by a glass base supporting the system of electrodes at the other end, said bulb at its open end having an edge with a smooth sealing surface for joining an annular surface area of said plate member within a tolerance of approximately 10 microns.
3.
The method of claim 1, wherein said first portion of the tube envelope is a glass cylindrical bulb which is open at one end and said second portion of the tube envelope is a glass base supporting the system of electrodes, said bulb at is open end having an edge with a smooth sealing surface for joining an annular surface area of said glass base within a tolerance of approximately 10 microns