Methods for lens configuration are disclosed. A method includes erasing a lens by heating the lens to a defined erasure temperature and writing a refractive index spatial distribution in the lens using an exposure pattern of directed ultraviolet (UV) light. The lens may be used as an ophthalmic lens or a lens used in industry. The lens comprises a rewriteable material, including, for example, liquid crystals. The lens may be erased using heat of a defined temperature. The lens may be rewritten by applying other exposure patterns to the lens using UV light.