Discharge tube.

摘要

A discharge tube comprises a sealed envelope (21) filled with a gas; an anode (27), cathode (28) and shielding electrode (23) built in the sealed envelope; and electrode holding pins (31-38). At least eight electrode holding pins penetrate a button stem (20) so as to be arranged at predetermined intervals on a circle coaxial with the button stem, and, of at least eight electrode holding pins, at least three hold the cathode, at least three hold the shielding electrode, and at least two hold the anode.