摘要 |
<p>The lens has a power profile related to the height (h) above its axis (A) and the addition (Add) corresponding to the degree of the wearer's presbyopia is defined by the formula: P(h) = f (PVL, ADD, h) + C (ADD, PVL) h<2> + B (ADD, PVL) where PVL is the power required for distance vision, f is a function of the evolution between the powers for close and distance vision, and B (Add, PVL) is a power correction coefficient dependent on the coefficient of spherical abberation.</p> |