Progressive addition lenses: Ccomparison of designs according to the visual fields they provide without astigmatic aberrations for far near and intermediate vision

Abstract

In this study the optical behavior of various deigns of progressive addition lenses were measured and analyzed. The goal was to provide information on the various designs of progressive addition lenses in order to enable professional opticians- optometrists to choose from different designs based on individual requirements for each user. Method and materials: The optical properties of 12 different designs of progressive addition lenses having the same power but different design were measured by means of an auto-focimeter. (TOMEY TL-100) specially modified for such specialized measurements. The lenses were fabricated having plano power (0.00 Ds) for distance vision and Addition +2.00 Ds diopters. The magnitude of unwanted astigmatism and the width of clear vision (having ≤ 0.50 Dc of unwanted astigmatism) in the areas of distant, intermediate and near vision were calculated for these designs. Results: The optical characteristics of the designs measured were significantly different. The differences were significant as to the reference sizes and widths of clear vision for far, near and intermediate, the amount of unwanted astigmatism, and the minimum mounting height on the spectacle frame