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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 Patients and Community

Local authorities have ordered a Stay Home order for most businesses in Houston/Harris county. We are currently operating from 10am-12pm for URGENT eye care visits (red eyes, infections, eye injuries, etc...), but no routine/wellness exams are being performed at this time. Furthermore, were are providing "Curbside" pickup of eyeglasses and contact lenses during those hours.

If contact lens wearers currently have less than three (3) months supply remaining, we highly recommend that they call to place an order now. Our doctors will approve up to an additional six (6) months supply. Furthermore, we will waive contact lenses shipping charges and ship directly to a home address at no charge.

With the day to day changes surrounding COVID19, we do not know how much longer our office will be open to the public. Due to this situation, we ask that any remaining glasses or contact lens supplies be picked up as soon as possible.

We thank you for your understanding and loyalty during this difficult time. Wishing you and you health and looking forward to serving you again soon.

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Dr. Maxwell Olumba OD

Dr. Rokeisha Joseph OD

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5505 West Orem Drive, #400
Houston, TX 77085