News & Blog

News & Blog

The Human Eye

8th January, 2013  


Many patients who are about to have laser eye surgery, often wonder about how the human eye actually works. Once you have decided to go ahead with the procedure, the human eye becomes a more interesting topic and patients are often keen to explore the eye’s inner workings. Laser surgery is obviously a significant decision and the more information you have as a whole, the more comfortable you will feel. The human eye obviously is the part of your body which enables you to see. It is said that the human eye can distinguish around 10 million different colours and this is because the retina allows conscious light perception. Facts about the human eye:

Eyes detect light which allows sight.

The eye is not shaped as a perfect sphere.

By the age of 13, the eye attains its full size (which is around 24 millimetres in diameter, a volume of 6 cubic centimetres and a weight of 28 grams).

The eye is made up of 3 coats. The outermost layer consists of the cornea and sclera, the middle layer consists of the choroid, ciliary body and iris and the inner coat is the retina.

The information the eyes receive is passed along the optic nerve to the brain, which provides a reaction (e.g. moving out of the way is something is coming towards the person).

Human eyes contain a small blind spot where the optic nerve passes through the retina. The brain uses the information from the other eye to fill in the vision gap so it is rarely noticed.

The part of the eye that allows the person to focus on different things is known as the lens. It changes shape so the person can focus on objects are various distances.

The eye blinks over 10,000 times a day.

Under the right conditions, the human eye can see the light of a candle at a distance of 14 miles.

Eyes can process 36,000 bits of information every hour.

The human eye can distinguish 500 shades of grey.

A human perceives 80% of all information about the environment they experience through sight.

The eye is filled with a clear jelly in its centre called the vitreous humor.

Pupils will enlarge if the light is too dim and if the light is too bright, pupils become small to keep out too much light.

People should try to not read in a car, train, bus or aeroplane because eye muscles are subjected to the strain of continually refocusing the words read.

The most active in the body is the eye muscle.

In order for the eye to see, it takes more than 2 million parts of the eye to work together.

Only 1/6th of the human eyeball is exposed to the outside world.

The older a human gets, the fewer tears they will produce.

In a normal life span, the eye will have seen almost 24 million images of the world.

Eyes will focus upon 50 things per second.