SU813539A1 - Metal halogen lamp - Google Patents

Description

(54) METAL HALOGEN LAMP

one

The invention relates to the electrical industry and can be used in the production of metal halide lamps designed to illuminate television studios and kinopavilonov, objects of color television shows and filming sports and other facilities from which color television programs are broadcast.

Metal halide lamps are used to illuminate sports facilities from which color television transmissions are used, consisting of a mercury quartz burner with cathodes mounted on a stem welded into an external flask filled with mercury, an inert gas and iodides of rare-earth metals (dysprosium and holmium), and also thallium and cesium iodides. These lamps have a relatively high luminous efficiency and high color quality 1.

However, with a lifetime, the light emitting metals react with the gaseous medium and the quartz wall of the burner. A significant portion of the light-emitting metals introduced into the burner in the form of their iodides oxidize or form

other compounds and more unsuitable for emitting light. This leads to a decrease in the luminous flux, a decrease in the quality of color rendering and a deterioration in other parameters that determine the useful life of the lamps. Also known are halogen lamps with a coating of the inner surface of a quartz burner with a layer of metal oxide. In these lamps, in order to prevent chemical interaction of the light-emitting metals with the quartz glass of the burner and, consequently, to stabilize the parameters of the lamp, the inner surface of the latter is covered with a film consisting of light-emitting metal oxides. For example, if the light emitting metal in the arc tube is scandium, the coating consists of scandium oxide. Films of metal oxides deposited on the inner surface of the burner, to some extent reduce the likelihood of the interaction of light-emitting metal, / 1ov with quartz glass

burner 2.

Claims (3)

However, such films cannot protect light-emitting metals from the interaction with gases released into the internal volume of the burner during the lamp life, as well as with the gases formed during the decomposition of water vapor that can be introduced into the burner with metal iodides. Closest to the proposed technical entity is a metal halide lamp containing a burner welded into an external flask with electrodes sealed in it, filled with mercury, an inert gas, and radiating additives in the form of rare earth metal iodides or mixtures with other metal iodides. Superstoichiometric rare-earth metals 3 are additionally introduced into the lamp. However, these lamps have insufficiently stable parameters and fail prematurely when using a quartz burner. The purpose of the invention is to improve the stability of the light, color and electrical parameters and the Service of the lamp. This goal is achieved by the fact that a metal halide lamp containing a quartz burner welded into an external flask with electrodes, filled with mercury, an inert gas and emitting additives in the form of rare earth metal iodides or a mixture of them with other metal iodides and super-stoichiometric light-emitting rare earth metals and rare earth metals and rare earth metals. in weight ratio to the iodide of the corresponding metal, equal to 0.08 - 0.15. As a rule, all light-emitting metal / W, whose iodides are added to the burner, are superstoichiometric, but in some cases it is advisable not to introduce all the metals. Thus, in the case of the use of multicomponent mixtures consisting, for example, of a combination of rare-earth and alkali metal iodides, only rare-earth metals should be additionally added to the burner; Since alkali metals such as lithium, sodium, cesium and others react with quartz glass burners. It is also not recommended to dose alkaline earth metals to the burner for the same reason. The super-stoichiometric light-emitting metals introduced into the burner compensate for the loss of metals during the service life due to reactions with quartz glass of the burners and the gaseous medium. As a result, the concentration of atoms of light-emitting metals during the service life remains constant, which determines the stability of light, color and electrical parameters and a longer lamp life. Due to the fact that the vapor pressure of over stoichiometrically introduced metals at operating temperatures of the burner is several orders of magnitude lower than the vapor pressure of iodides, the presence of free metals in the burner does not affect its radiative characteristics, which are exclusively determined with metered metal iodides. Example. In the burner lamps with a capacity of 3500 W with an internal volume of 170 cm dosed; OG; 20, HOB 35, T1J 10, CsJ 15, metallic dysprosium, 3, metallic holmium 3, mercury 135. Initial luminous flux of the lamp 312600 lm, color temperature 6000 K, Rct 93, lamp current 18.0 A, voltage on the lamp 224 B. Claims of Invention A metal halide lamp containing a quartz burner welded into an external flask with electrodes sealed in it, filled with mercury, an inert gas, and radiating additives in the form of rare earth metal iodides or mixed with other metal iodides and introduced with superstoichiometric rare earth metals, is different This is due to the fact that, in order to increase the stability of parameters and service life, rare earth metals are introduced in a weight ratio to the corresponding metal iodide of 0.08-0.15. Sources of information taken into account in the examination 1. UK Patent No. 1282805, cl. H 1 D, 1972. 2. US patent number 3377498, cl. 313-221,1971. 3. The patent of Germany No. 2408112, cl. H 01 J 61/18, 1975.