Question

why ray of light not deviates when passes through optical center

Answer 1

for passing the light!!!

Answer 2

hii guyzz
Deviation is the change in the direction of the ray while pasing through the lens.The middle portion of the lens is comparatively flat and there is a point on the principal axis and inside the sphere through which all the undeviated rays passes. Undeviated thts dosnt mean that there is no refraction. when v say there is no deviation v only mean that the incident and tge emergent rays are parallel to each othr.For thin lenses the refraction inside the lens is negligible therefre v say that the ray passing through the optical centr s a stright line, but in the cse of thick lens v cnt sy so.....hope it hlps