How do vision numbers work

February 17, February 27, Scoot your chair back and once you are at the proper distance, start reading the letters starting at the top. When you reach a line of letters that you cannot read, the line above it will be your approximate vision strength. Call us today! You may need reading glasses or bifocals to fix the problem.

Outside the U. Eyecare providers measure your visual acuity as part of an eye exam. The Academy recommends that you get a baseline eye examination at age This is when early signs of disease or vision changes may happen. About Foundation Museum of the Eye. Eye Exams. By Celia Vimont. Edited By David Turbert. A standard Snellen vision testing chart. Others can see items that are close but cannot see those far away.

This condition may be caused by myopia nearsightedness. A comprehensive eye examination by a doctor of optometry can diagnose what is affecting your ability to see well. In most cases, your doctor of optometry can prescribe glasses, contact lenses or a vision therapy program that will help improve your vision. If the reduced vision is due to an eye disease, you may be prescribed ocular medication or another treatment.

Other important vision skills, including peripheral awareness or side vision, eye coordination, depth perception, focusing ability and color vision, contribute to your overall vision ability. For onsistency, doctors of optometry in the United Sates use 20 feet as the standard for measuring sharpness of vision. Other countries express visual acuity in their own way. Many factors affect visual acuity. Vision conditions, like nearsightedness, farsightedness, or astigmatism, or eye diseases affect clarity of vision.

Some people can see well at a distance but cannot bring nearer objects into focus. The condition can be caused by hyperopia farsightedness or presbyopia loss of focusing ability. Others can see items that are close but cannot see items that are far away. In a comprehensive eye examination, a doctor of optometry can diagnose what causes, if any, are affecting your ability to see well.