Electron tube

摘要

The present invention relates to an electron tube comprising, at least, a cathode electrode and a face plate having a photocathode which are arranged at one end of a body, and a stem arranged at the other end of the body for defining the position of an electron entrance surface where the electron emitted from the photocathode reaches. The object of the present invention is to provide an electron tube which can reduce its size and has a structure for improving the workability in its assembling process. In particular, the electron tube in accordance with the present invention comprises a bonding ring, provided between the face plate and the cathode electrode, for bonding the face plate and the cathode electrode together. The bonding ring is made of a metal material selected from the group consisting of In, Au, Pb, alloys containing In, and alloys containing Pb.