AN OPHTHALMIC PROGRESSIVE ADDITION LENS FOR A PRESBYOPIC WEARER; METHOD FOR PROVIDING SUCH A LENS

摘要

An ophthalmic progressive addition lens for a presbyopic wearer which has a prescribed far vision mean refractive power a non nil prescribed addition, ADD_p, the lens having a far vision reference point, a mean refractive power, PPO(α, β), a module of resulting astigmatism, ASR(α, β), a meridian line, ML(α, β), the (α, β) functions being determined in as-worn conditions of the lens by the wearer for gaze directions (α, β) joining the center of rotation of the eye, CRE, and the lens, wherein α is a lowering angle in degree and β is an azimuth angle in degree, and wherein a lens criterion, CRIT, fulfils following requirement: 0.38≤CRIT≤4.50, where: CRIT=NumeratorCRIT/DenominatorCRIT, NumeratorCRIT=(A1/A2)+(PPO(α_FV, β_FV)/(100·ADD_p)); A1=α100%−α85%; A2=α100%−α60%; DenominatorCRIT=[(PeaksMean/ADD_p)±(PPO(α_FV,β_FV)/(8·ADD_p))]³.