Power of normal eye is: September 2007

Ans. D: +60 D The power of the front surface of the cornea is about 43D, and, if it were in air, the power of the crystalline lens at rest (its minimum power, not accommodating) would be about 20D. This adds up to 63D. But the 'schematic' eye is said to have 60 D of power: a little power is lost when the ray exits the cornea into aqueous, since this means it is going from a material with higher index to a material of lower index.