Aluminum Mirror, Borofloat, 101.6 mm, λ/10, 450-700 nm

The 40D20ER.1 Broadband Aluminum Mirror is an excellent general purpose, broadband reflector. This 101.6 mm (4.0 inch) diameter mirror is made from a 17.7 mm thick Borofloat® 33 substrate which is coated with the ER.1 aluminum coating. Borofloat® 33 has low thermal expansion and is an excellent substrate for most applications. The ER.1 enhanced aluminum coating may be used wherever a broadband visible and near infrared reflector is needed. A multilayer dielectric stack deposited over the aluminum film boosts reflectance and improves the durability of the coating. The 40D20ER.1 has an average reflectivity greater than 93% from 450–700 nm. This mirror has a λ/10 surface flatness and a 15-5 surface quality.