NIEDERDRUCK-QUECKSILBERDAMPF-ENTLADUNGSLAMPE SOWIE LUMINOPHORMISCHUNG

A low-pressure mercury discharge light source, particularly a fluorescent lamp of high wall loadability with luminescent coating, including an inactive component, comprises a vessel (1) coated on its inner surface with a luminescent coating (2) including an inactive component, the vessel (1) being pervious to radiation of predetermined wavelength, an excitable and ionizable filling consisting of a rare gas and mercury, the filling being arranged within said vessel (1) and means (3) for maintaining a gas discharge process within the vessel (1). The luminescent coating (2) consists of at least one luminescent component and an inactive component, the inactive component (such as alkali earth metal diphosphate) contains grains of average size smaller than that of grains forming the luminescent coating (2), the inactive component being positively charged and the amount of the inactive component lying in the range of about 0.1 mass% to about 2 mass% compared to the mass of the luminescent coating (2).