IEC TR 60747-5-12:2021

IEC TR 60747-5-12:2021(E) discusses the terminology and the measuring methods of optoelectronic efficiencies of single light emitting diode (LED) chip or package without phosphor. White LEDs for lighting applications are out of the scope of this part. This technical report provides guidance on - terminology of optoelectronic efficiencies of single LED chip or package without phosphor, such as the power efficiency (PE), the external quantum efficiency (EQE), the voltage efficiency (VE), the light extraction efficiency (LEE), the internal quantum efficiency (IQE), the injection efficiency (IE), and the radiative efficiency (RE); - test methods of optoelectronic efficiencies of the PE, the EQE, the VE, the LEE, and the IQE; - review of various IQE measurement methods reported so far in view of accuracy and practical applicability; - the measuring method of the LED IQE based on the temperature-dependent electroluminescence (TDEL); - the measuring method of the LED IQE based on the room-temperature reference-point method (RTRM); - the measuring method of the radiative and nonradiative currents of an LED; - the relationship between the IQE and the VE, which leads to introduction of a new LED efficiency, the active efficiency (AE) as AE = VE × IQE.