Determine the strength of a lens needed to allow a person with a far-sighted eye with a near point of Pnar= 2.0 m (near point means the closest distance for which an object can be imaged on the retina) to read comfortably at 0.25 m?
a) If an emmetrope has an accommodation of 53 D, what is the person's near point?
b) If a former emmetrope wears reading glasses of +2D to read at a distance of 25 cm, what is the near point without glasses?