Eye learned cool stuff today ;)

The word retina means "little net" or "net-like" because when Aristotle (or some ancient doctor man) cut open an eye and looked at it, he saw the net of blood vessels coming out from behind the eye and spreading over the surface of it. Turns out there was a net of nerves there that he just couldn't see.

Meanwhile, behind the retina is a layer of "pigmented epithelium." The pigment is quite dark, and in fact is the black spot you see when you look inside someone's pupil. However, behind that layer is the "choroid plexus" - a very rich network of blood vessels (that make cerebro-spinal fluid, responsible for the blood-brain barrier). Well it turns out that if you shine a lot of bright light inside the eye, you will see the red of the choroid plexus...hence red eyes in flash cameras!

Oh yeah, and LASIK eye surgery works by effectively removing parts of your cornea, since light passes through your cornea and then your lens. This way, even though your eye is mis-shaped and your lens isn't focusing stuff on the exact spot of the back of your eye, your cornea can be cut down and will fix your problem...assuming your cornea isn't lasered off altogether. :P