Dichroitic Splitters decompose light beams in 2 spectral divisions. This is used in the optical measurement technique, when for example LEDs of two different wavelengths are applied. Contrarywise, 2 beams of different wavelengths can also be consolidated with the help of dichroitic splitters. The application ranges from UV and visible light to infrared. In the majority of cases the splitter is situated in a 45°-angle to the incident beam; however, this is not mandatory. Important for the right choice of beam splitter is the polarisation state.