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. A release layer is formed on the annular surface. A mask layer of a biocompatible metal is formed above the release layer. The mask layer is separated from the substrate.