A method is provided for making a mask configured to improve the depth of focus of an eye of a patient. A substrate is provided with a mask forming feature. The mask forming feature comprises an annular surface that has a curved profile that corresponds to the curvature of a corneal layer of the eye....http://www.google.de/patents/US7491350?utm_source=gb-gplus-sharePatent US7491350 - Method of making an ocular implant
