METHOD OF DENSIFYING FLUORIDE OPTICAL THIN FILM, AND FLUORIDE OPTICAL DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a method of densifying the structure of an optical thin film deposited on an optical element.;SOLUTION: The method of densifying the optical thin film includes: a process of loading a fluoride optical device 18 on which a fluoride optical thin film 20 is stacked into a reaction furnace 2; a process of heating and densifying the fluoride optical thin film by introducing gaseous fluorine into the reaction furnace 2; a process of cooling the fluoride optical device 18 loaded into the reaction furnace 2; and a process of taking out the fluoride optical device 18 from the reaction furnace 2. The temperature in the reaction furnace in the densification process is controlled to 200 to 400°C and the concentration of the gaseous fluorine to 10 ppm to 100%.;COPYRIGHT: (C)2005,JPO&NCIPI