Quenching problems in inorganic luminescent materials

Quenching problems were investigated on inorganic luminescent materials for fluorescent lamps. It could be shown that the decrease of luminescence intensity under the influence of short-wave UV radiation is not only a function of the irradiation time but also depends strongly on the activator concentration and a mechanical treatment. The photochemical luminescence quenching represented by the intensity loss as a function of the irradiation time can be expressed as a sum of three exponential terms, constants and exponents of which contain the concentration of virgin and UV induced lattice defects in both the bulk and the surface. To explain the complex quenching process the theory of radiationless energy transport was used.