MGF2 OPTICAL THIN FILM INCLUDING AMORPHOUS SILICON OXIDE BINDER, OPTICAL ELEMENT PROVIDED WITH THE SAME, AND METHOD FOR PRODUCING MGF2 OPTICAL THIN FILM

摘要

An MgF₂ optical thin film 100 is formed on an optical surface of a base material 10. The MgF₂ optical thin film 100 includes MgF₂ particles 12 and an amorphous silicon oxide-based binder 13 which exists on the surfaces of the MgF₂ particles and between the MgF₂ particles. Owing to this amorphous silicon oxide-based binder 13, the optical thin film 100 can have high mechanical strength and high adhesion to the base material 10, while having excellent environment resistance and a lower refractive index.