Abstract: An apparatus for causing the polymerized excess monomer to separate from a molded lens by increasing the surface energy of the flange area of one mold piece, causing the polymerized excess monomer to stick thereto. Specifically when manufactured under inert atmosphere conditions, a particular manifold is needed to supply an oxygen bearing gas, air, to the area to be treated while preventing the oxygen from contaminating the lens manufacturing area of the molds or diluting the nitrogen atmosphere of other lens process areas. It has been found that generation of the ionized oxygen by means of a corona treatment electrode sufficiently increases the adherence of the polymer to the mold piece so treated.