To solve the following problem: the process for manufacturing differential thickness lenses typically includes a curing step, which may involve UV, heat, or other similar curing process, however, as a result of the curing step, the material of the lens shrinks at different rates due to the differential thicknesses.

Regarding the method of producing the contact lens 10 that is compensated for power deviation from target due to differential shrinkage, the method includes the steps of: designing the lens 10 to have a first area having a first thickness and upper and lower areas 14 and 16 each having a second thickness different from the first thickness and a cylinder axis; dividing the whole angular ranges of the cylinder axis into a plurality of angular ranges and determining a plurality of power correction factors, one for each of the divided angular ranges; and modifying the lens using a selected one of the plurality of power correction factors corresponding to the cylinder axis ranges of the lens containing the cylinder axis of the lens.