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Home » Your Eye Health » Eye Exams » 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!

Dear Richie Eye Clinic & LASIK Center Family and Friends,

As we head into the Holiday Season and the New Year, I have some news to share.

As many of you know, we have added some new doctors to our team in the last couple of years. Dr. Josh Spedding OD, our new Optometrist, joined us last summer and is currently seeing patients in both our Northfield and Faribault offices. We are thrilled to have Dr. Spedding on our team and welcome him and his family to the area.

Dr. Cory Miller, MD joined us in 2021 and we welcomed Dr. Mike Reinsbach, MD to our team this past summer. Both are Board Certified Ophthalmologists and skilled surgeons specializing in High Technology Cataract Surgery with Advanced Lens Implants, LASIK, Retinal injections, MIGS Surgery for Glaucoma, as well as the usual medical and surgical management of eye disease.

With the addition of these high performing providers, I am transitioning my role in 2023 to concentrate on Practice Development while continuing to serve as the Medical Director overseeing our practice protocols and procedures. Dr. Miller and Dr. Reinsbach will be assuming my day-to-day patient care duties.

I have done my best over the past several months to tell everyone of this transition plan while personally introducing Dr. Miller and Dr. Reinsbach; please accept my apologies if I missed any of you during this time.

Rest assured, we will continue our commitment to providing cutting edge care. Starting in 2023 look for Dropless Cataract Surgery, Light-Adjustable Lens Implants, and so much more…

Thank you for the Trust and Confidence you have shown me over the past 32 years. Please feel free to call us at (507) 332-9900 for questions, concerns, or clarification.

Sincerely,

Mike Richie, MD

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