| abstract |
This invention relates to an optical material comprising a polymer which has a structural unit represented by the formula <IMAGE> (a) wherein X1 and X2 are the same or different and are each hydrogen or deuterium, and R1 is a chain hydrocarbon group having 1 to 5 carbon atoms, a cyclic hydrocarbon group (with or without a substituted lower alkyl group) having 3 to 6 carbon atoms or a deuterium-substituted chain hydrocarbon group having 1 to 5 carbon atoms in an amount of at least 5 mole % of the polymer. |