US Patent 7700714 Optical element and achromatic lens

There are provided an optical element that comprises a polymer which has a structural unit derived from a specific dihydroxy compound typified by 2,2-bis(4-hydroxyphenyl)-1,1,1,3,3,3-hexafluoro propane (bisphenol AF) and in which the relationship between a refractive index nD and an Abbe number νD satisfies the following formula (I):nD+0.0076×νD≦1.78  (I)and that is used for correction of chromatic aberration, and an achromatic lens using the optical element.