Why doesn't refraction take place when the ray of light is passing through the optical centre
Hello,
The ray passing through optical center does not deviate because the curvature of the Lens at the incident and exit point are exactly opposite. So that the deviation at the first point is cancelled out at the other point.Note:- for a thin lens the ray appears to be passing straight. But for a thick Lens there will be a lateral shift i.e. the incident ray will be parallel to the emergent ray.