PDP (Plasma Display Panel, known as plasma display in Taiwan) is a display technology that uses gas discharge. Its working principle is very similar to that of fluorescent lamps. It uses plasma tubes as light-emitting elements. Each plasma tube on the screen corresponds to a pixel. The screen uses glass as the substrate. The substrates are spaced at a certain distance and are air-tightly sealed around them to form discharge spaces. The glass substrate refers to the screen, the glass layer that can hold the inert gas.