Weight distributions of spherical and cylindrical power deviations for progressive addition lens design

The weight distributions (WDs) of spherical and cylindrical power deviations with the multiple convolution processing schemes indicate that the areas of the far and near zones can be increased by changing the WD without changing the distribution of the mean sphere. When the number of the multiple convolution processing schemes changed from 0 to 15, the areas of the far and near areas increase by 35.7% and 76.5%, respectively, and the maximum peripheral astigmatism increased from 0.75 to 1.5 ADD. The increasing maximum peripheral astigmatism will lengthen the period for the wearer to wear the PALs, and increase discomfort.