From visible light to near infrared band, the average reflectivity is high. A protective film is plated on the silver film, which can prevent oxidation and prolong the service life. Compared with aluminum film mirror, the reflectivity in visible light to near infrared band is higher. Compared with the dielectric film mirror, the reflectivity is less affected by the incident angle, so it can be used for various incident angles. Plated with protective film, it is not easy to scratch when wiping with cloth.