In the field of in vitro diagnostic devices, Fraunhofer EMFT has already realized a large number of prototypes with optical detector principles. These include devices for detecting bacteria and viruses as well as for analyzing body fluids such as blood. The range of optical detectors used extends from simple photodiodes to photomultipliers based on glass tubes or on silicon avalanche photodiodes. Methods such as absorption, chemiluminescence or fluorescence are used.