Abstract: A laser discharge tube comprises a discharge envelope and an anode and cathode both disposed within the envelope. The envelope includes a capillary tube having a hole. In this hole the tip portion of the anode is inserted. Outside the envelope there is provided a magnet generating a magnetic field which lies in the vicinity of the anode.

Abstract: A hollow cathode laser comprises a cathode body which constitutes a part of a discharge envelope. The cathode body has a cathode hole coaxial with the body. It further has three anode holes which are through holes extending parallel to the axis of the cathode body and communicating with the cathode hole through slits, respectively. Three cylindrical anodes extend respectively through the anode holes and are spaced by a given distance from the inner surfaces defining the respective anode holes. The anodes have portions which protrude through the respective slits and which are positioned flush with the inner surface defining the cathode hole in the circumferential direction thereof.

Abstract: A discharge tube comprises a vessel containing rare gas; a plurality of electrodes (having a cathodic part and anodic part therein) and so arranged tandem in said vessel that a glow discharge is kept in a discharge gap between each said cathodic part and said anodic part of the preceding electrode, and that an optical path is allowed to let through each negative glow part of said glow discharge adjacent to said cathodic part; means to apply a dc voltage across every said discharge gap in series; and means to supply metal vapor to one of said glow discharge at the most low potential end of said means to apply dc voltage, whereby metal ions formed in said one of said glow discharge are carried down throughout said vessel.