How Sharp Is Your Vision? Here’s How It’s Tested.

January 18, 2022

Acuity of vision, also termed visual acuity, describes the clearness of your vision when measured from 20 feet away. Visual acuity is the most common medical measurement of your eyes’ visual capability without help from eyeglasses or contact lenses. Optometrists use these measurements to determine the lens strengths of their patients’ eyewear. 

At the office of Tropicana/215 Fwy, we are experts at helping our patrons with their eye health as well as choosing the eyeglasses and contact lenses that are perfect for them. We will scrupulously evaluate the health of your eyes and patiently answer all of your questions. Your care and comfort are our top priorities. 

If someone’s visual acuity measurement is 20/20, then he has a good quantity of detail of an object that’s 20 feet away. If another person’s measurement is 20/40, she can see the same amount of detail from 20 feet away as the person with 20/20 vision would see from a distance of 40 feet. Only 35 percent of adults have 20/20 acuity without help from glasses, contacts or laser surgery. People with 20/200 vision are considered legally blind. Many people can have 20/20 vision with help from corrective lenses.

Having 20/20 vision doesn’t mean your sight is perfect, however. Vision power also encompasses your eyes’ coordination, depth perception, color visualization, peripheral vision and ability to focus. Children’s visual acuity should be tested regularly to monitor the development of their vision. 

An optometrist uses two kinds of visual acuity exams: the Snellen and Random E. The Snellen chart is 11 rows of capital letters. The top line has one very large letter. Each subsequent row has more letters that get increasingly smaller. You cover one eye and call out the smallest line of letters you can see clearly. 

The Random E test has only a capital letter E and is for children and adults who have difficulty identifying letters. ‌As the chart progresses from top to bottom, each E faces up, down, left or right and shrinks in size. The patient identifies the directions of the Es until they can’t be seen clearly. 


Tropicana/215 Fwy’s professional team is made up of friendly specialists who are eager to help you feel comfortable and relaxed while receiving the very best in optical treatment. We have earned the trust of all of our patrons and look forward to earning yours. For more information about our business and how we can help you, please don’t hesitate to stop in or call us to schedule an appointment.