Patent ID: 7717563

Claim:
A method of designing a soft contact lens, the method comprising the steps of: (a) measuring or defining a wavefront generated by passage of light through a selected eye and using the wavefront to generate a computer model of the optical characteristics of the selected eye; (b) measuring or defining the topography of the cornea of the selected eye; (c) incorporating into the computer model a soft contact lens, the posterior surface topography of which is defined by the topography of the cornea, offset by an arbitrary amount intended to represent the tear layer thickness of the selected eye, said lens having a defined thickness at a selected locus on the anterior surface; (d) calculating a desired topography for the anterior surface of the lens such that the wavefront will be corrected to assume a desired pattern when passing through the computer model eye/lens combination; (e) remodeling the lens in isolation from the eye by adapting the posterior topography of the lens to a desired posterior topography to be manufactured; and (f) recalculating a modified anterior topography for the lens required as a result of adapting the posterior topography, the modified anterior topography being intended to preserve the desired wavefront pattern defined in (d) when the lens is in situ on the selected eye; wherein steps (e) and (f) are performed substantially simultaneously by dividing the lens into a plurality of notional elements, each element being moved towards or away from the posterior surface as appropriate so as to arrive at the desired posterior topography and simultaneously modifying the anterior surface topography.