What is 20 40 vision on a prescription?
If you have 20/40 vision, for example, that means you need to be 20 feet away to see an object that people can normally see from 40 feet away. If your visual acuity is not 20/20, you may need corrective eyeglasses, contact lenses, or surgery.
How do I convert my glasses prescription to 20 20?
The 20/20 equivalent is 6/6 because they use a 6-meter test distance. The second number is the smallest line of letters that a patient can read. In other words, 20/20 vision means that at a 20-foot test distance, the person can read the 20/20 line of letters.
What is a glasses prescription out of 20?
This means that you can see an object clearly from 20 feet away. Someone with normal vision can stand 200 feet away from an eye chart and see it as clearly as a legally blind person sees it from a distance of 20 feet.
Does a person with 20 40 vision need glasses?
A person with 20/40 vision sees things at 20 feet that most people who don’t need vision correction can see at 40 feet. This means that they are nearsighted, but only slightly. A person with 20/40 vision may or may not need eyeglasses or contacts, and can discuss his or her options with a doctor.
How far can you see with 20 40 vision?
The American Optometric Association states that a person with 20/20 vision can clearly identify a row of 9mm letters from 20 feet. So if you have 20/40 vision, this means that you can see only as good as a normal person can see at 40 feet away from an eye chart.
What is the normal cylinder of eye?
The abbreviation stands for Cylinder. It represents the amount of lens power you need for astigmatism. If you do not have astigmatism, you may not have anything indicated in this column. The value may be a plus or a minus, and in most cases, the value will be between +/-0.25 to +/-4.00.