Tailoring of the Color Conversion Elements in Phosphor-Converted High-Power LEDs by Optical Simulations

Ray-tracing simulations are used to identify the demands for angular homogeneity of the white light emitted from phosphor-converted white light-emitting diodes having color conversion elements (CCEs) of constant thickness. The simulations reveal that a constant thickness of the CCE by itself is not sufficient for a homogeneous white light emission. Rather the height and the broadness of the CCE as well as the phosphor concentration have to be precisely adjusted in order to assure a homogeneous white light emission.