Hi,
You eyes do the same thing. If you look at a bright object and then shut your eyes you'll see a negative image of the object. There's a proper name for this but I can't remember it.
i dont know about the proper name, but i can tell you that this is the sun burning your retina. the section of your retina that is picking up the image of the sun gets fucked up hardcore, so you cant see from that area (that negative image thingy).
something to do with photoreceptors and all that jazz.