The Process of Sight
The process of sight occurs when the eyes and the brain work together to transform light images into sight. Light rays first pass through the transparent cornea, which focuses them through the pupil to the lens. When light rays reach the lens, it adjusts its shape to fine-focus the images onto the
 retina which covers the back of the eye. Once the retina has received the light images, it translates them into electrical impulses. The optic nerve carries these impulses to the visual cortex of the brain, where they are interpreted into sight.
Anatomy of the Eye
At the very front of the eye is the clear window called the cornea. To see clearly the cornea and the lens must work together to focus light onto the back of the eye. Inside the eye we can see the coloured part called the iris. Right in the middle of the iris there's a black circle which is the pupil. The pupil is a hole in the iris that let's the light through to the lens which is positioned just behind the iris and the pupil.
 The lens is made of a clear, flexible gel surrounded by the transparent lens capsule. This outer membrane is kind of like a piece of saran wrap or you could think of it as being like the skin on a sausage.
The lens is held in place by hundreds of little wire-like strands, which go from the base of the iris to a structure known as the ciliary body. These strands are
 round and function much like the cables on a suspension bridge. The ciliary body produces the fluid which normally keeps the eye inflated.
If we go backwards in the eye,
we can see that the back of it is lined with the retina. The retina is the eye's light-sensitive layer that sends visual signals to the brain. The lens is the part of the eye that helps focus light on the retina. In a normal eye, light passes through the lens and gets focused on the retina. To help produce a sharp image, the lens must remain clear - just like in a camera.
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