Important point of refraction in eye is-

Ans. is 'd' i.e., Anterior surface fo cornea Refractive system of eveo The main function of refractive system of eye is to focus the light rays on the retina. The cornea (especially anterior surface) is the most important refractive surface of eye. The refractive power of cornea depend on two factors (i) Refractive index of cornea (Directly related), (ii) Radius of curvature (inversly related),o Second important refractive structure of eye is lens with refractive index 1.386 - 1.406. Center (nucleus) of lens has maximum refractive index (1.46) amongst all the refractive structures of eye.o Third important factor determining the refractive power of eye is the axial length of eyeball. 1mm change in axial length leads to change of 3D in refractive power. For example, 1 mm shortening in axial length causes hypermetropia of 3D and 1mm lengthening causes myopia of 3D.Refractive indexMediumAirCorneaAqueous humourLensVitreous humorRefractive index10001-3761-3361-386-1-4061-336