Abstract: Automated systems and methods for characterizing light-emitting devices as a function of the electrical and temperature properties of the device are disclosed. The system includes a thermal stack assembly operatively connected to a temperature control system and that operably supports and controls the temperature of the light-emitting device. A power supply provides varying amounts of electrical power to the light-emitting device. A control computer controls the power supply and the temperature control system based on a user-defined electrical and temperature profiles. A light processor optically analyzes light from the light-emitting device as its electrical and temperature properties are varied. The control computer receives and processes electrical signals from the light processor and outputs one or more optical characterizations as a function of electrical and temperature properties of the light-emitting device.