| 摘要 |
An electric discharge lamp comprises a case with a transparent wall wherein the inner surface is coated with a luminescent material layer. The luminscent material is at least partially made up of a luminescent compound of general formula: Ba7-x-y Mx Euy F12 Xu Yv. In this formula, M is selected among calcium, magnesium, strontium and zinc; X and Y each represent an element selected among chlorine and bromine; x, u, and v range between 0 and 2, with u+v=2; and y ranges between 0.00001 and 2. The luminescent compound has high values of light output intensity, in the spectrum visible part, for excitation wavelengths higher than 300 nanometers. Thus it is possible to use an excitation radiation less actinic than in the case of discharge lamps of prior art, while avoiding the presence of mercury in the atmosphere contained in the case. The invention, therefore, makes it possible to decrease the dangerous physiological effects on living beings and to eliminate risk of mercury pollution. |
