As the lens is elastic, it will change shape, getting fatter for close objects and thinner for distant objects. The cornea is a transparent membrane which forms the outer coating of the eyeball. Its main purpose is protection and it is the outer-most refractive surface of the eye. Retina Imagine that the eye is like a camera, and the retina is the film. The retina is a fine sheet of nerve tissue lining the inside of the eye.
Rays of light enter the eye and are focused on the retina by the lens.
The retina produces a picture which is sent along the optic nerve for the brain to interpret. It is rather like the film in a camera being developed so that pictures can be produced. Macula Again, imagine that the eye is like a camera. The retina is made up of a delicate tissue that is sensitive to light, rather like the film in a camera. The macula is found at the centre of the retina where the incoming rays of light are focused.