Abstract
An improved method for electrolytic colouration of alkali halide crystals is described. In this method a matrix-type, multipointed cathode is used to produce a homogeneous colour centre distribution in crystals. To obtain equal injection conditions for each cathode point an adjustable constant-current power supply is used, which has separate channels for controlling the current of each individual cathode point. With this method sufficiently low and homogeneous colour centre concentrations, e.g. applicable colour centre laser crystals, can be obtained.