The amazing inner working
of your eye

 
inner working of eye.jpg
 

Your eyes are working from the moment you wake up to the moment you go to sleep. Your eyes take in an enormous amount of information about the world around you – shapes, colours, movements, and more. They then send the information to your brain, where it's processed, so the brain knows what's going on outside of your body.

The eye is a very complex organ that is approximately 1 inch (2.54 cm) wide, 1 inch deep and 0.9 inches (2.3 cm) tall. Following are explanations for some of the various parts of the eye:

 

Cornea
The cornea is the transparent membrane which forms the outer coating at the front of the eyeball and covers the iris (the coloured part) and pupil. It also focuses light on the retina.

Sclera
The sclera is the white of the eye and forms the outer coating of the eyeball.

Pupil
The pupil is the dark circular hole in the centre of the iris which allows light to enter the retina. The pupil regulates the amount of light that enters the eye.

Iris
The iris is the coloured circle surrounding the pupil. It changes the size of the pupil and allows different amounts of light to enter the eye. When people ask you what colour your eyes are, they mean what is the colour of your iris.

Lens
The lens is a transparent structure behind the iris, the coloured part of the eye. The lens bends light rays so that they form a clear image at the back of the eye – on the retina. As the lens is elastic, it can change shape, getting fatter to focus close objects and thinner for distant objects. 

Vitreous
The vitreous is the clear, jelly-like substance that fills the inside of the eye from the lens to the retina.

Macula
The macula is the small area at the centre of the retina responsible for our central vision. The macula is very important as it gives us the vision needed for detailed activities such as reading and writing, and the ability to appreciate colour.

Retina
The retina is the light-sensitive inner lining of the back of the eye. Imagine that the eye is like a non-digital camera, and the retina is the film. Rays of light enter the eye and are focused on the retina by the cornea and lens. The retina produces an image which is sent along the optic nerve for the brain to interpret, rather like developing a camera film.

Optic nerve
A bundle of nerve fibres that carry impulses for sight from the retina to the brain.