What affects the durability of LED?

The main cause of the drop of luminous flux and reduction of LED durability is the heat generated at the semiconductor junction (junction “p-​n”). In order to guarantee proper operation of LED, the heat from “p-​n” junction must be transferred by conduction or convection, for example, by means of elements which conducts heat well and ventilators. For heat conduction from connector, radiators and ventilators are used. In case of the lack of usage of appropriately designed heat sink or ventilator, the temperature of diode increases, as constant operation at high temperature will cause durable decrease of luminous flux (luminous efficiency) and LED durability. Shortening LED durability may also take place because of inadequate power supply. For instance, in case when LED power supply current value is higher than the maximum value, it results in increase in the connector temperature and reduction of durability. The use of well-​fitting power systems and radiators (recommended by LED manufacturers) guarantees an obtainment of the maximum durability.