Sixth Grade
Worksheets
How Eyeglasses Work
Our eyes work by bending and focusing images. Light enters the eye through the transparent covering called the cornea and moves on through the opening called the pupil. The images that we see focus on the retina at the back of the eye. For some people, images do not focus at just the right spot. Maybe they focus in front of the retina or maybe behind it. Either way, the result is blurry images.
If you are having problems seeing clearly, you might go to see an optometrist. Optometrists use a machine called a phoroptor to determine just what type of eye problem you have and what kind of glasses you need to correct the problem.
Probably, you will look through the phoroptor at an eye chart. The optometrist will adjust lenses and other settings. As he or she does that, he will keep checking with you to see which adjustment works best for your eyes.
After his examination is completed, the optometrist will know just which prescription to write for you. The prescription tells a technician in a lab how to make the lenses for your glasses. The technician grinds and polishes lenses exactly as the optometrist ordered.
