Patent ID: 7229173

Claim:
A method for designing a progressive addition lens, comprising the steps of: a.) providing a first progressive addition surface having a first add power and a first corridor of a first length; b.) expressing the first surface as a first plurality of sag values; c.) multiplying the first plurality of sag values by a first blending function; d.) providing a second progressive addition surface having a second add power and a second corridor of a second length; e.) expressing the second surface as a second plurality of sag values; f.) multiplying the second plurality of sag values by a second blending function that may be the same or different from the first blending function; g.) adding the multiplied first and second plurality of sag values to produce a third progressive surface having the first add power, a third corridor wherein a length of the third corridor is at least about 1 mm less than the first and second corridor lengths.