Vidicon tube front plate seal - is formed by heating solder ring between front disc and tube rim under pressure

摘要

The front end of a vidicon tube has a glass disc (6) mounted on the open end of the glass vacuum tube (5) with a ring shaped signal electrode (7) around the joint region. On the inside of the disc is a transparent conductive layer (8) and an photo conductive layer forming photo electric converter/collector electrode behind a grid electrode. To form the joint a ring of solder (19) is included between the disc and the rim of the tube. This has lead and tin as its main constituents, and has antimony and zinc as lesser constituents. The ring is heated under pressure at which the liquid and solid phases of the alloy are formed simultaneously.