Abstract: A low pressure metal vapor discharge lamp has a double-tube type discharge vessel consisting of a fully closed outer glass bulb and an inner glass tube substantially coaxially disposed in the outer glass bulb, the inner glass tube being closed at its fixed end and opened at its free end. The space within the discharge vessel is filled with a small amount of a metal and a rare gas of a low pressure. A single cathode is disposed within the space inside the inner glass tube, while a plurality of anodes are disposed in the annular space between the inner glass tube and the outer glass bulb. According to the invention, a number of discharge channels corresponding to that of the anodes are formed between the single cathode and respective anodes, via the opening end brim of the inner glass tube. In operation, anode oscillations take place alternately in respective anodes to cause a self-excitation switching operation, so that a plurality of plasmas are formed.

Abstract: A low pressure metal vapor discharge lamp has a double-tube type discharge vessel consisting of a fully closed outer glass bulb and an inner glass tube substantially coaxially disposed in the outer glass bulb, the inner glass tube being closed at its fixed end and opened at its free end. The space within the discharge vessel is filled with a small amount of a metal and a rare gas of a low pressure. A single cathode is disposed within the space inside the inner glass tube, while a plurality of anodes are disposed in the annular space between the inner glass tube and the outer glass bulb. According to the invention, a number of discharge channels corresponding to that of the anodes are formed between the single cathode and respective anodes, via the opening end brim of the inner glass tube. In operation, anode oscillations take place alternately in respective anodes to cause a self-excitation switching operation, so that a plurality of plasmas are formed.

Abstract: A low pressure metal vapor discharge lamp has a discharge envelope of a double tube structure filled with an inert gas and a small quantity of metal. The discharge envelope comprises a sealed outer glass bulb, and an inner glass tube disposed within the outer glass bulb substantially concentrically therewith and having one open end and the other closed end. The lamp further has a single cathode inside the inner glass tube, a plurality of anodes disposed exteriorly of the inner glass tube and interiorly of the outer glass bulb, and a permanent magnet disposed near the open end of the inner glass tube for applying a magnetic field of a fixed intensity near the open end.

Abstract: The invention relates to an ionization detector comprising a discharge section which generates ultraviolet rays and a detector section which collects ionic current caused or altered by the photoionization of a sample gas with the ultraviolet radiation. A container holds the two sections together and a pointed cathode is spaced at least several millimeters from an anode in order that the electric discharge may be executed as field-emission discharge.