Electroluminescence is a phenomenon in which light emission occurs when current passes through PV cell. Electroluminescence is based on the same principle as a light emitting diode (LED). The main advantage of this method is that it can detect hidden defects in the structure of the PV cell. This method makes visible the current distribution in the PV module (PV cell) and eventual inhomogeneities and local defects. In the electroluminescence image we can see dark and light areas. Fully functional monocrystalline PV cell without any defects has homogenous light distribution. Beside, on the EL image of the multicrystalline PV cell are visible edges of the crystals.
