Most impoant factor determining convergence of light rays on retina is -: (A) Length of eyeball, (B) Dioptre power of lens, (C) Refractive index of cornea, (D) Physical state of vitreous
Answer is C. The cornea is the most imponat refractive surface of the eye with a refractive index of 1.376. The reason for msximum refraction lies in the fact that when light travel from one refractive medium to other. In eye, there are three such refracting interfaces:- i)Air, ii)Aqueous iii) lens Reference : Optics of human eye 4th edition page15-20