A resin with a favorable index of refraction and transparency even without using heavy atoms or inorganic oxide fine particles by means of a polymerizable monomer having a 1,3,5-triazine ring represented by formula 1. (In formula 1: A is a group represented by formula 2, (in formula 2: R1 represents a hydrogen atom or a methyl group, T represents an alkylene having 1-10 carbon atoms, and R2 represents O or NH), and B1 and B2 are each independently groups represented by formula 3, formula 4, or formula 5 (in formulas 3-5: R3, R4, and R5 represent an alkyl group having 1-10 carbon atoms, an aryl group, or an aryloxy group, n1 and n3 are integers from 0-5, and n2 is an integer from 0-7, however when there are at least two of each of R3, R4, and R5, these may be the same or different from each other).)