How the eye works

How it works?

Your Vision begins when a light ray reflects off an object and and enters your eye through your Cornea, then the Cornea bends or refracts the ray of light that passes through your pupil. Your Iris opens and closes (which makes your pupil bigger and smaller) to regulate the amount of light passing through. The ray of light then passes through the lens, which actually changes shape so it can bend the rays and focus them on the retina at the back of your eye. The Retina is a thin layer of tissue at the back of your eye that contains millions of tiny cells called Rods and Cones. They are called Rods and cones because of their distinct shapes. Cones are concentrated in the macula. In bright condition, cones provide clear, sharp vision and detect Colours and fine details. Rods are located outside the macula and extend all the way to the outer edge of the retina. They provide side vision. They also allow the to sense motion and help us see in dim light. These cells in the retina converts the light rays into electrical impulse. The optic nerve sends these impulses to the brain where an image is produced.

Eye problems:

Colour blindness - Colour blindness is when some people see colours differently and have a difficult time distinguishing certain colours.

Lazy eye - Lazy eye is a vision development disorder in which and eye fails to achieve normal visual acuity, even with glasses or contact lens.

Swollen eyelids - A swollen eyelid occurs when there is inflammation or excess fluid in the connective tissues surrounding the eye. Swollen eyes can be painful, and affect both the upper and lower eyelids.

Cataract - Cataract are cloudy areas that develop within the eye lens. Most cataracts are due to age-related changes in lens. Most of the time cataracts are small and don't effect your eye sight however if it gets larger or thicker you might need surgery.

By: Amy Reed