Many people take for granted that they can see without any conscious effort, but in reality, vision is very complex. Many different parts of the eye must work together to help a person see. Each part has a unique and vital purpose, and there are a surprising number of moving parts when it comes to the human eye.


1. Cornea

The vision process begins with the cornea, the front surface of the eyeball. It is located in front of the iris and pupil and allows light to come into the eye. The cornea has a vertical diameter of around 11 millimeters and a horizontal diameter of 12 millimeters. It is around 550 microns thick, which is just over 0.5 millimeters. It is made up of five layers: the corneal epithelium, Bowman's layer, the corneal stroma, Descemet's membrane, and the corneal endothelium.

cornea parts of the eye

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