The application of spherical silica in infrared reflective materials mainly involves making thin films and multilayer films.The membrane material of ultrafine particles has good application prospects in the light bulb industry.High pressure sodium lamps and various iodine arc lamps used for photography and photography require strong lighting.However,after the filament is heated,69%of the energy is converted into infrared,indicating that a considerable amount of electrical energy is converted into thermal energy and consumed,with only a small portion converted into light energy for illumination.At the same time,the heating of the lamp tube can also affect the lifespan of the lamp.How to improve the luminous efficiency and increase the illumination level has always been a key issue that needs to be urgently solved.The birth of ultrafine particles provides a new way to solve this problem.Since the 1980s,scientific and technological personnel have made multi-layer interference films using nano SiO2 and nano TiO2 particles,with a total thickness of micrometers.They are lined on the inner wall of the bulb cover,resulting in not only good light transmittance but also strong infrared reflection ability.According to experts'calculations,under the same lighting brightness,this type of lamp can save 15%of electricity compared to traditional halogen lamps.