Laborarory setup for electrooptical characterisation of III-V photodetectors on chip level, especially InGaAs/InP pin-PDs, APDs, and SPADs, with respect to dark current/count characteristics, spectral responsivity, photon-detection efficiency, afterpulsing etc.; chip size < 10 x 10 mm²; pulsed laser wavelength: 1550 nm; cryogenic cooling option, temperature range: 77 - 300 K.