Mitsubishi Denki Kabushiki Kaisha

Toshiro Kajiwara

Yoshinori Anzai

Takeo Saikatsu

Goroku Kobayashi

Michihiro Tsuchihashi

Yoshiji Minagawa

Keiji Watanabe

Keiji Fukuyama

Hiroshi Yamazaki

Ko Sano

Hiroyoshi Yamazaki

Shunichi Morimoto

Yojiro Yano

An electrode for discharge light source which is suitable for discharge display on account of its high reliability and outstanding discharge characteristics attributable to the metal conductor which is formed 1-5 .mu.m thick in the discharge container and also to the film of the material for secondary emission which is formed on the metal conductor from a compound composed of LaB.sub.6 and Ba in an amount of 0.01-20 mol % of LaB.sub.6 or a compound composed of LaB.sub.6, Ba in an amount of 0.01-20 mol % of LaB.sub.6, and Ca in an amount of 0.01-5 mol % of Ba, and is 0.5-2 .mu.m thick so that it is free of pin-holes.

Electrode for discharge light source

A low-pressure mercury vapor discharge lamp comprises a tubular bulb having an inside diameter of from 22 mm to 35 mm, an electrode-to-electrode distance of from 400 mm to 1,200 mm, and an inner surface coated with a phosphor. A rare gas including Kr and a mercury vapor source are sealed in the bulb, which is energized by an igniting device having a high-frequency power supply connected to a DC power supply for generating a substantially sinusoidal high-frequency output voltage, and a quiescent period generator connected to the high-frequency power supply and including a switch 17 turned on and off at least once during each half cycle to provide a quiescent period and thereby produce a substantially square wave high-frequency output voltage having rise and fall times of 2 .mu.s or less.

Low-pressure mercury vapor discharge lamp

A lighting circuit for an electric discharge lamp according to the present invention is constructed in such a way that a switching device is provided at an output terminal of a high frequency inverter which produces a substantially sinusoidal output voltage, and that, by controlling this switching device, an output to the low pressure electric discharge lamp is stopped at the rising part of the abovementioned output voltage in its half cycle, while the output is supplied to the low pressure electric discharge lamp at the voltage level in the vicinity of the maximum instantaneous value thereof. By use of the high frequency inverter of a smaller capacity and less radio noise than those in the conventional device, the operating efficiency of the low pressure electric discharge lamp can be increased.

Lighting circuit for electric discharge lamp

A low pressure discharge lamp has a nonlinear arc path formed by a partition in a lamp envelope wherein the lamp envelope is polyhedral and the partition is fixed to the corners of said polyhedron lamp envelope.

Low pressure discharge lamp with polygon shaped envelope

A lamp primarily containing neon gas is supplied with alternating electrical power at a frequency of not less than 5 kHz. The discharge current is determined on the basis of the gas pressure such that no striations occur. If necessary, getter means including a metal element belonging to the second, third, fourth or fifth periodic group are provided near each electrode, oriented so as not to interfere with any electron emissions from the lamp electrodes.

Growing community of inventors

Kamakura, Japan

Toshiro Kajiwara