The power for a contact lens can be calculated based on data measured at refraction.
Parameters:
(1) required lens power measured during refraction testing in diopters
(2) back vertex distance (BVD) in meters (distance between the lens and the cornea)
required power for contact lens in diopters =
= (measured power in diopters) / (1 – ((BVD in meters) * (measured power in diopters)))
