New methodology for the assessment of the thermal resistance of laser diodes and light emitting diodes

In this paper, we propose a new method to evaluate the thermal resistance of laser diodes and light emitting diodes based on the analysis of common emitter characteristics (emission spectrum, power–current and voltage–current characteristics) measured in CW condition. This method has been used to assess the thermal resistance of commercial GaAlAs laser and light emitting diodes emitting at 780 nm and 872 nm respectively. Finally, the method is compared with classic threshold current method carried out on the laser diodes.