Blind spot facts:

• The blind spot, or the optic nerve head, lies in the retina. 

• The blind spot has no photoreceptor cells, like the rods and the cones. So there is no image detection in the area. 

• You don’t notice your blind spot because that spot in your eye doesn’t match the spot in the other eye. 

• Each eye sends information to the brain, filling in what was missing. 

• Sometimes, your brain will fill that missing information into what they think should be there. It causes one kind of optical illusion. 

More blind spot facts (but more detailed):  

• The optic nerve, that acts like an electrical wire, carries info to the brain from the retina. The small round spot where the nerve enters the retina is called the optic disc, or the blind spot. They contain no photoreceptor cells, no light detecting cells there. As a result, you have scotoma. The reason why you don’t notice this is because the opposite eye can see where the other eye cannot. Which means that one eye can see normally, while the other eye cannot.

Sources used: 

https://atlanticeyeinstitute.com/blind-spot-is-it-normal/ 

https://www.aao.org/museum-eye-openers/blind-spot 

https://www.britannica.com/science/blind-spot  

Credits to Tobu for the music. Sunburst - Tobu. 

Music link: https://www.youtube.com/watch?v=1-0-4HqyvXE