Research and development of new phosphors for solid state LED applications

The search for efficient phosphors for colour conversion for white light emitting LEDs (w-LEDs) has recently raised new interest in the photoluminescence behaviour of phosphors materials doped mainly with rare earth ions. Another very recent research topic is than undoubtedly the development of new solid-state phosphors, which are suitable for the construction of tuneable white light sources (so-called circadian sources) based on LEDs. It is a complete optical characterization, verification of thermal stability and usability in real conditions. Materials studied are, for example, ternary sulphides of the general formula ALnS₂ (where A = Li, Na, K, Rb, Cs or their combinations, Ln = La, Gd, Lu, Y or their combinations) doped with Eu²⁺ ions.