The story of the development of vision does not end with the eye cells connecting to the vision part of the brain. It turns out that we have to learn to see the world. While we have a innate ability to produce metal images of the world around us we have to learn to make sense of these images.
A research group recently published a study that looked at whether babies could see optical illusions like the one shown below.
The brain waves showing that the babies could see the square that we see only showed up somewhere between the sixth and eighth month of their lives. Our brain has learned tricks about seeing the world including visualizing a square where there is none as seen above.(link to article) These tricks allow us to make sense of the visual information that our brain is receiving from our eyes.