I don't personally know this but I looked it up and these were some answers I got.
1. There are no photoreceptors present, therefore vision is lost when light hits this spot (the blind spot)
2. Vision is lost when light hits the blind spot because the blind spot lacks photoreceptors, so light focused on it cannot be seen.
3. The back of your eye contains all of the detectors which sense when light hits them, this is how you see. All of these signals are sent to the brain by the optic nerve, which connects to the back of the eye to receive the signals. Where it connects, however, there are no detectors so there is a small patch which each eye is unable to see and the brain has to fill in based on data from the other eye.
Hope it helped!
