The main fields of interest of the research group "Phosphors" at the Chair 6 Materials for Electronics and Energy Technology (i-MEET) are: (i) Improving solar cell efficiency by using of phosphors with up- and down-conversion of light. (ii) Engineering of nano-particles of storage phosphors for medical imaging. (iii) Improving growth of plants by the photoluminescence-conversion of green light into red light and (iiii) Development of new phosphors for the white light generation with light emitting diodes (LEDs). Several techniques (solid-state reactions, sol-gel processes and liquid phase epitaxy) are used in the lab and in cooperation with different institutions for manufacturing of the phosphors. A large variety of spectroscopic techniques are available at the i-MEET including life time measurements of the excited state of different kinds of activators.