Optic nerve. Artwork of transverse and longitudinal sections through the optic nerve. The optic nerve collects impulses from the light sensitive cells of the retina and relays them to the brain. Top shows the optic nerve leaving the ocular bulb (eyeball) via the optical canal. The retina, which contains the light sensitive cells is across centre (yellow), the choroid, which lines the inside of the eye is red, and the sclera, the white of the eye is pink. There are no light sensitive cells where the optic nerve joins the retina, resulting in a blind spot. Within the optic nerve are the main artery (red) and vein (blue) of the retina. Surrounding the optic nerve is the insulating pia-arachnoid (orange and red).