As a key component in color TVs and displays, tube sockets are prone to multiple failures during use due to their complex working environment. After the color TV is turned on, the sound is normal, the image is fuzzy, and it looks like a colorful cloud. After a few minutes or tens of minutes, the image becomes clear gradually. This is a typical tube socket failure. Due to the structure of the tube base, the shape of the electrode and the level of production and manufacturing technology, the tube base focusing electrode is in a long-term high-pressure working state. When it is affected by harsh environments such as high air humidity and serious air pollution, the tube base focuses on the two poles of the discharge chamber. Corona discharge phenomenon, and produce very corrosive ozone (O3, a strong oxidant, smell like fishy smell). In addition, when abnormal high voltage pulses are generated in the work of color TV, arc discharge will be generated, and high-energy charged particles will bombard and focus. On the surface of the cavity electrode, the coating on the surface of the electrode is destroyed and metal ions are sprayed out gradually, so that the burning phenomenon occurs and the electrode coating is destroyed. At the same time, O3 corrodes the damaged electrode. Furthermore, the bromine-based flame retardants in ordinary PBT plastics are very easy to release corrosive bromide to induce discharge under the above-mentioned environment. All these corrosive substances undergo chemical reactions under the action of an electric field to generate acids or salts. The substance is adsorbed on the plastic surface in the discharge cavity, so that the insulation resistance in the focusing discharge cavity of the tube holder decreases, the leakage current increases, the focusing voltage decreases, and finally the image is blurred.