Patent ID: 8480229

Claim:
A method for stabilizing contact lenses comprising: a) providing a lens design with a initial set of stabilization zone parameters, b) applying a merit function to the lens design based on balancing moments of momentum, and c) creating a contact lens design with improved stabilization based on the application of said merit function to the lens design with a initial set of stabilization zone parameters; wherein said merit function is selected from the group consisting of MF 1 =√{square root over ( W R (Rot/ R REF ) 2 +W C (Cent/ C REF ) 2 )}{square root over ( W R (Rot/ R REF ) 2 +W C (Cent/ C REF ) 2 )} (Equation 1) MF 2 =√{square root over ( W X ( X range /X REF ) 2 +W Y ( Y range /Y REF ) 2 +W θ (θ range /θ REF ) 2 )}{square root over ( W X ( X range /X REF ) 2 +W Y ( Y range /Y REF ) 2 +W θ (θ range /θ REF ) 2 )}{square root over ( W X ( X range /X REF ) 2 +W Y ( Y range /Y REF ) 2 +W θ (θ range /θ REF ) 2 )} (Equation 2) and MF 3 =√{square root over ((Rod/ R REF ) 2 +W C (Cent/ C REF ) 2 +W S (Stab/ S REF ) 2 )}{square root over ((Rod/ R REF ) 2 +W C (Cent/ C REF ) 2 +W S (Stab/ S REF ) 2 )}{square root over ((Rod/ R REF ) 2 +W C (Cent/ C REF ) 2 +W S (Stab/ S REF ) 2 )} (Equation 3) and wherein; W R and W C are weighting factors and can take values between 0 and 1; X Range , Y Range and θ Range are lens performance variables in stability in horizontal direction vertical direction and rotation of the completed lens design; X REF , Y REF and θ REF are lens REF and REF are lens performance variables in stability in horizontal direction, vertical direction and rotation of the initial lens design; W X , W Y , W S and W θ are weighting factors. Rot Cent and Stab are lens performance variables in rotation centration and stability of the completed lens design; R REF , C REF and S REF are lens performance variables in rotation centration and stability of the initial lens design, and R REF , C REF and S REF are weighting factors.