| 摘要 |
Provided is a low-dispersion optical glass that is formed of a fluorophosphate glass in which the molar ratio of the content of O 2- to the content of P 5+ , O 2- /P 5+ , is 3.5 or more and that has an Abbe's number (½ d ) of over 70 or has an F - content of 65 anionic % or more, and the optical glass enables the suppression of the volatilization of a glass component when an optical glass formed of a fluorophosphate glass is produced or when an obtained glass in a molten state is caused to flow out to shape it into a glass shaped material, so that the variation of properties such as a refractive index, etc., involved in the fluctuations of a glass composition and the variation of quality such as the occurrence of striae can be suppressed. |
