| abstract |
PROBLEM TO BE SOLVED: To provide an optical system suitable for mass production, using an optical resin having excellent optical characteristics in a visible region and having characteristics required as an optical resin, particularly excellent environmental resistance characteristics. An optical system having a plurality of optical elements, wherein a copolymerization ratio of 9,9 bis [4- (2-hydroxyethoxy) phenyl] fluorene is 35 mol when a dicarboxylic acid component is 100 mol%. % To 45 mol% of the first optical element, and at least one of the first and second optical elements on the optical path before and after the first optical element, to which an ultraviolet absorber is added. Composed second And an optical element. |