Vision is different from touch.
If you look at something, say a beach ball, the image falls on both sides of our retina
and will go to both sides of the brain.
But there is a crossing and it has to do with the fact that our retinas are divided where they send information to the brain.
Start by imagining that you are looking at the plus sign.
Anything presented to the right visual field, in this case the banana
falls on the left half of the retina in both eyes and is passed to the left hemisphere.
Inversely, anything presented to the left visual field, for example a beach ball
is passed to the right hemisphere because it falls on the right half of the retina.
Thus, your left hemisphere “sees” only the right half of the world
and your right hemisphere “sees” only the left half of the world.