What Are Visual Defects And How Common Are They ?
Beginning of paper
?
The human eye does alot more than allowing you to see. It is very
complex and has many parts and features which can have defects. However, to
understand defects you must first know how the eye works.
First light passes through the cornea, which is the transparent part of
the sclera, or white o ....
Middle of paper
.... the light rays
onto the retina forming an image in reverse and upside-down. Finally light-
sensitive cells in the retina transmit the image via the optic nerve to the
brain by electrical signals. Then the brain flips the image so it looks right-
side-up to you. You can find a diagram of the above on page 3.
The most common visual defects are nearsightedness and farsightedness.
In nearsightedness, also known as myopia, the eye is longer than usual. This is
corrected by using a concave lens ....
------------------
Word count: 344
Page count: 2 (approximately 250 words per page)