Why do some people have to wear glasses?
  • Some people wear glasses because they canít see things very well either close up (like to read) or in the distance (like to play sport).
  • Other people might wear glasses because they have whatís known as a lazy eye. A lazy eye means one of your eyes doesnít focus very well or doesnít move to look in the right direction easily. To help fix lazy eye you wear a patch over your good eye so your lazy one has to work all the time.
  • Glasses help correct your eye sight so you can see more clearly.
  • Normal vision works like this - Light enters your eye through the clear membrane at the front of your eye called your cornea. Then it passes through the lens in your eye to hit the sensitive retina at the back of your eye.
  • If youíre short sighted (you canít see things very well in the distance) your lens is shaped so that when light passes through them they focus the image before it reaches your retina. That makes your vision blurry.
  • If youíre long sighted (you canít see things very well close up) your lens are shaped so that when the light passes into your eyes itís focused for a position thatís further back than where your retina is. That makes your vision blurry too.
  Did You Know?
  • Short sightedness is also known as Myopia
  • Long sightedness is also known as Hyperopia
  • Some eye sight problems that kids have can be fixed by wearing glasses for a while.
  • The first glasses were invented about 900 years ago and they had to be held up in front of your eyes.
  • Before glasses were invented some people used to look through water droplets to get things magnified.
Make a water drop lens

What you need:
A glass of water
An old magazine

What you do:
Get a small droplet of water and gently place it over a word and see what happens.
The water bends the light and that makes the image look bigger than what it is. It magnifies the object.
Next time you go fishing or you have a big fat fish for dinner, ask someone to hook the lenses out of the fishís eyes for you. Use them to magnify the words in that magazine again.
Did you hear about the man who turned into a pair of glasses?
He made a spectacle of himself!
From Cenara Davies-Bell

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