Phenyl vinyl silicone oil and phenyl hydrogen silicone oil of which the refractive index match with fumed silica are prepared, and then add fumed silica as reinforcing fillers to prepare optical transparent phenyl silicone rubber. By using tetramethyl hexamethylene diamine as a catalyst, organic polysilazane (OPSZ) coated on a silicone rubber surface achieves low-temperature curing and siliceous transition, and a dense coating having low gas permeability is obtained. Optical performance, oxygen permeation flux, and anti-sulfuration are then tested, the results show that the OPSZ coating surface is continuous, uniform, dense and free of cracks and voids, while the coating section is dense, uniform, seamless, without cracks, and have good adhesion to the silicone rubber when the coating thickness was < 32-35μm. The coatings have excellent transparency, light transmission and gas shielding properties. With a coating thickness of over 12μm, the oxygen permeation flux remains unchanged, lamps after coating have good anti-sulfuration ability, and the luminous flux maintains over 99.9%. The siliceous conversion time can be effectively shortened by increasing the heating temperature and relative humidity.