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 . in the preferred embodiment , the flange around the convex , male piece of the lens mold is corona treated so that when the mold pieces are separated after lens polymerization , the flashing of excess polymerized material surrounding the lens cavity adheres to that male , convex piece flange while the lens is removed with the female , concave piece .