Method of making an ocular implant

A method of making a mask configured to improve the depth of focus of an eye of a patient, the method comprising:

• providing a substrate with a mask forming feature comprising an annular surface extending between an inner periphery and an outer periphery, the annular surface being centered on a central axis of the mask forming feature, the annular surface having a curved profile between the inner periphery and the outer periphery corresponding to the curvature of a corneal layer of the eye;
• forming a release layer on the annular surface;
• forming a mask layer of a biocompatible metal such that the release layer is between the mask layer and the substrate;
• and
• separating the mask layer from the substrate.