an apparatus and method for directing accelerated electrons to at least part of one surface of one ophthalmic mold piece prior to filling with monomer and lens polymerization . in particular 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 .