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Home » Private: Eye Exam Q&A » Common Tests » Snellen Chart

Snellen Chart

Hopefully by now, we’ve all seen one. The projected or wall-mounted Snellen eye chart, usually topped by the big letter “E”, is a common visual acuity test used to measure your sharpness of vision at multiple distances.
 
Arranged as a pyramid of sorts, the letters in the Snellen chart are specifically chosen and arranged to test your sharpness and clarity of vision at a baseline distance of 20 feet. During a visual acuity test, the Snellen eye chart is viewed as a projection, or mounted on a wall.
 
Handheld versions of Snellen charts are used for testing near vision as well.
 
By viewing or reading each line from top to bottom (with one eye covered at a time), your eye doctor can gain a general approximation of the quality of your visual acuity, or sharpness. Where a line of characters begin to become difficult to see is the approximate measurement of your vision.
 
The Snellen chart serves as a beginning—not an end—to a comprehensive eye examination.

What does “20/20” vision mean?

Snellen charts help to determine a baseline for your vision in each eye—a baseline typically measured against “20/20” vision. This means when you are 20 feet away from an object, you can comfortably see details that most people with normal vision can also see at 20 feet distance.
 
If you have 20/30 vision, that means what you see comfortably at 20 feet, can be seen by a person with “normal” vision at 30 feet. Your vision is weaker, in other words.
 
Conversely? In the rare instances where vision may test better than normal on a Snellen chart, a value of 20/10 vision means that you can see clearly from a distance of 20 feet, what a person with normal vision sees well at a distance of 10 feet. Make sense?
 
In fact, if you look closely at a Snellen eye chart, you’ll see the vision values associated with measuring your vision on the right or left side of each line of characters.
 

Special thanks to the EyeGlass Guide, for informational material that aided in the creation of this website. Visit the EyeGlass Guide today!

stouffvillecovid

Dear Valued Patients,

We would like to clarify to our patients that despite the province-wide lockdown starting Thursday, December 24, our office is still open.  Patients who have appointments already booked will still be seen as scheduled.

We will continue to operate in a way that is in alignment with provincial guidelines and is designed to keep you and our staff safe while still allowing us to deliver the high standard of eye care you are accustom to.

Our doctors have modified their schedules to increase physical distancing. As a result, fewer appointments are available, and we are having to assign these appointments to people with immediate and greatest needs.

We will also be:

• Using telehealth appointments, when appropriate, to deliver care from a distance.

• Time in our Frame Gallery will be scheduled for patients to try on and choose eyewear.

• All eyewear adjustments, repairs, and pick-ups will be scheduled.

• Our doors will be closed as we will not be accepting walk-ins at this time.

• Contact lenses will continue to be shipped directly to patients.

We look forward to servicing our amazing community with all their eye care needs and thank you for supporting us as we navigate these unprecedented times.

Stouffville Optometry