| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for forming reflection preventing film with which a reflection preventing film having little light absorption loss and excellent transmissivity is obtained, and an optical device provided with a reflection preventing film like this. SOLUTION: In the method for forming a reflection preventing film by laminating thin films composed of materials with respective refractive indices different individually on a substrate 2 for an optical device by vapor phase film formation, the thin film 4 corresponding to the first layer on the substrate 2 for the optical device side is formed under a film forming temperature lower than the temperature for forming the thin film 10 corresponding to the outermost layer. In this case, the film forming temperature for the first layer thin film 4 is preferably <=20 deg.C. Also, the first layer thin film is preferably constructed with a metal oxide layer such as Al2O3 or Ta2O5.
|
