El (electroluminescent) is a kind of physical phenomenon that applies electricity to emitting cold light. as an ac voltage is applied to the electrodes, the electric field causes the phosphor (zns) to rapidly charge and discharge, resulting in the emission of light during each cycle. one usage of the above principle is the advanced el film, which has advantages and is widely used. \n\napplications: \n\n(1) lcd backlighting source \n\n(2) watches and clocks \n\n(3) toys, electronic gifts and christmas illumination\n\n(4) ad boards.