OLED (OrganicLight-Emitting Diode), also known as organic electro-optic display (OLED). OLED is a current-type organic light-emitting device, which is caused by the injection and recombination of carriers, and the luminous intensity is proportional to the injected current. Under the action of the electric field, the holes generated by the anode and the electrons generated by the cathode move, and are respectively injected into the hole transport layer and the electron transport layer to migrate to the light-emitting layer. When the two meet at the luminescent layer, energy excitons are generated, thereby exciting the luminescent molecules to eventually generate visible light.