Customized Polynomial Contact Lenses via Wet Etching

Customized polynomial contact lenses are meant to correct high-order optical distortions in the human vision, beyond focus and astigmatism, but they are not yet a commercial solution mainly due to reproducibility and cost issues. Aiming at circumventing these obstacles to market, this paper investigates the possibility of fabrication of such lenses by wet etching of a silicon mould and subsequent casting of the lens polymer. The proposed technique to obtain the mould is based on ordinary anisotropic etching of c-Si with an aqueous KOH solution, where a subtle step ensures the achievement of an arbitrary smooth topology.