Question

why there is no vision possible possible on blind spot

Answer 1

this is so because our eye can see only upto a limited extent. and also the image gets narrow with the distance.at last point ,ie the blind spot our vision meets .hence no vision possible thereafter

Answer 2

because there are photoreceptors in eyes which help us to see objects.Blind spot os an area in eye where very few or no photoreceptors are present.That's why we are not able to see from blind spot