Optical thin film manufacturing method and optical film manufacturing method

The present invention forms an optical thin film having a desired optical characteristic. When forming an optical thin film 11 on a substrate 10 that is to be treated by including oxygen gas in a vacuum atmosphere and heating a metal material to discharge a vapor, a flow rate or partial pressure and a film thickness for obtaining a desired optical characteristic are determined from a previously determined relationship between the optical characteristic of the optical thin film 11 and oxygen gas flow rate or oxygen partial pressure, and an optical thin film 11 of the determined film thickness is formed with the determined flow rate or partial pressure. If the optical thin film 11 is formed after plasma treatment of the surface of the substrate 10 that is to receive the vapor deposition, itis possible to form an optical thin film 11 with high optical density without reducing resistance. 本发明形成具有期望的光学特性的光学薄膜。在使真空气氛中含有氧气，加热金属材料以使得放出蒸气，在被处理对象基材10上形成光学薄膜11时，根据预先求得的光学薄膜11的光学特性和氧气的流量、氧的分压值的关系，求用于获得期望的光学特性的流量值或分压值和膜厚值，