A method is provided for use in reducing a size of halo effect in an ophthalmic lens. The method comprises: providing data indicative of a given ophthalmic lens with a first pattern providing prescribed vision improvement, processing said data indicative of the features of the first pattern and generating data indicative of a variation of at least one feature of the first pattern resulting in a second pattern which maintains said prescribed vision improvement and reduces a size of halo effect as compared to that of the lens with the first pattern.