Patent ID: 7288893
Filing Date: 2007-10-30
Classification: H01J

Abstract:
1. A gas discharge tube comprising: a sealed container in which gas is contained; an anode part disposed in said sealed container; a cathode part defining an electric discharge part for generating an electric discharge with said anode part, said cathode part being disposed inside said sealed container in such a manner as to be distanced from said anode part; an electric discharge path restricting part being cylindrical and conductive and having a throughhole for narrowing said electric discharge path, said electric discharge path restricting part being disposed between said anode part and said cathode part, and being adapted to be electrically connected with an external power source; and an electric-discharge-path-restricting-part supporting part for supporting said electric discharge path restricting part, said supporting part being electrically insulating, wherein said electric discharge path restricting part has a projecting part which is cylindrical and projects toward said cathode part side, and a ratio (D/H) of an outer diameter (D) of said projecting part to a height (H) of said projecting part is in a range of 0.5 to 2.0.