The structure, how they work and solving some eye problems.
How does the eye work?
Light enters the eye through a small round opening called the Pupil. This is the black dot in the middle of your eye. Surrounding the pupil is a circle of muscle known as the Iris. Colored chemicals in the iris give it various shades of brown, blue, or green.It is able to change the size of Pupil to control the amount of light that passes into the eyeball.
Just behind the pupil is the lens. It is flexible like rubber and small about the size of your little fingernail. When the light falls on the lens,it creates an image and reaches at the back of the eye called the retina.
When it reaches the retina, the image that our eyes see is actually upside down because the images that we see are made up of light reflected. Then, why don't we see the image upside down? That's because our eyes send it to the brain through the optic nerve and the brain turns the picture the right way up and tells you what you are looking at.