The optical device having a predetermined surface profile of the invention is fabricated by forming a multi-layered dielectric film on the surface of a solid composition layer having a glass transition temperature of not lower than 100 C. The solid composition layer is formed by molding and curing a polymerizable organic group-having fluid composition. The curing may be effected through photopolymerization or thermal polymerization of the polymerizable organic group in the composition, and a predetermined surface profile is transferred onto the composition layer from the mold used. The cured composition is released from the mold, and this is coated with a multi-layered dielectric film.