Fluorescent lamps using a mercury dispenser

Abstract

Mercury dosing in fluorescent lamp is essential because fluorescent lamp exploit the ultraviolet radiation emitted by mercury atoms. As regards mercury dosing into the bulb, the method which drops a few drops of liquid mercury through the exhaust tube has been employed. Such conventional method in production is of advantage to exhaust the gaseous impurities from the bulb but brings about various defects quality and characteristic. To eliminate such disadvantages, a manufacturing method which uses a mercury dispenser such as a strip mounted around the electrode and releases mercury within the tube by means of R. F heating after sealing is introduced. Advantages using mercury dispenser are as follows; (1) the quantity of mercury enclosed in the lamp is very precise, (2) the pressure fluctuation of argon fill can be reduced, therefore it is possible to prevent the fluctuation of lamp life and to increase its average life. (3) lumen maintenance can be improved because less mercury condensation on the phosphor coating and getter action of mercury dispenser. As a conseguence, the total amount of light output during life is increased and the total lamp efficiency is also improved.