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To Our Valued Patients,

With the evolving situation of the Coronavirus (COVID-19) pandemic and under the guidelines of the Health Officer of the Alameda and Contra-Costa Counties, our offices are open to provide eye and vision care.

Please keep in mind that in order to maintain social distancing protocols and to limit further transmission of the virus, we will be working with a reduced staff and seeing a fewer number of patients as compared to our “normal” schedule. Priority will be given to the most urgent medical cases. We will be implementing a number of measures (including altered check-in/check-out procedures, limiting the number of patients in the office and waiting room, face covering for all persons, temperature screening, etc) that will change your experience in the office. In addition, we will be ramping up our already strict disinfection policies and we will continue to monitor and abide by all local, state and, federal guidelines. Please bear with us through this new reality as these changes are designed to protect you and our staff.

We hope to see you soon and appreciate your trust in us to continue to meet your eye care needs. Stay safe and stay healthy!

The Turner Eye Institute Team

Home » Eye Care » 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!

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