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Eye Anatomy | How does the Human Eye Work?

 

Eye-Anatomy-how-does-the-human-eye-work

 

In a number of ways, the anatomy of the human eye works much like a digital camera

 

  • Light is focused primarily by the cornea — the clear front surface of the eye, which acts like a camera lens.

 

  • The iris of the eye functions like the diaphragm of a camera, controlling the amount of light reaching the back of the eye by automatically adjusting the size of the pupil (aperture).

 

  • The eye’s crystalline lens is located directly behind the pupil and further focuses light. Through a process called accommodation, this lens helps the eye automatically focus on near and approaching objects, like an autofocus camera lens.

 

  • Light focused by the cornea and crystalline lens (and limited by the iris and pupil) then reaches the retina — the light-sensitive inner lining of the back of the eye. The retina acts like an electronic image sensor of a digital camera, converting optical images into electronic signals. The optic nerve then transmits these signals to the visual cortex — the part of the brain that controls our sense of sight.

 

Eye-Anatomy-how-does-the-human-eye-work

http://www.webmd.com/eye-health/picture-of-the-eyes