Electron tube envelope assembly with precisely positioned window

摘要

An electron tube comprising a window having a radiation-sensitive layer. The window is laid on a bearing surface of an envelope normal to the tube axis. There is no sealing material in the seam between the bearing surface and the window. The seam is sealed hermetically by a mass of indium or an indium alloy in which a metal wire is embedded along the circumference of the seam. The wire can be soldered with indium or an indium alloy. The seal is made by locally melting the indium or the indium alloy by a heated ultrasonically vibrating heat transfer member. The heat transfer member traverses the circumference of the seam.