Final answer:
The formula to calculate lens power is P = 1/di + 1/do, with di = 0.02 m for retinal distance, do = infinity for distant vision or do = 0.25 m for close vision, and diopters as the unit of power.
Step-by-step explanation:
The formula to calculate optical power (P) for lenses when you know the image distance (di) and object distance (do) is given by P = 1/di + 1/do. For clear vision, the image must be formed on the retina. Therefore, the image distance (di) is typically set at 2.00 cm for calculations, which must be converted to meters to match the unit of diopters (di = 0.02 m). When considering distant vision, we assume do is infinite (do = ∞), and for close vision, do is typically around 25.0 cm or do = 0.25 m after conversion. In optical terms, the power of a lens is measured in diopters, where 1 D = 1/m, meaning you must use meters for the distances in the formula. Therefore, to solve for P using the binocular PD (pupillary distance), you would still apply the same formula, but the total seg inset calculation would potentially use the PD to customize the lens power for each eye.