Abstract: Hard substrates such as ophthalmic lenses or molds are coated with a UV curable monomer which is polymerized to construct a scratch resistant coating on a surface of the lens. The present invention is directed to an apparatus for and method of applying the UV curable monomer to the surface of the ophthalmic lens or mold. Polymerization of the monomer occurs by radiation of UV light while the lens is encased in a curing chamber. The spin coater of the present invention has the following advantages: Excess monomer is collected in a dish away from UV exposure and is readily disposed of. The substrate is revolved at a high rate of speed during the application of the coating to achieve a uniform coating of monomer. Only the holder and substrate are moved to the curing chamber minimizing the items exposed to UV light. The UV light is electrodeless, it has a standby mode and operates cyclically during use so as to prolong its life and to allow a greater degree of control over extent of polymerization.