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 . operation of the apparatus occurs automatically and can be performed by using pneumatic as well as electronic circuits .