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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!

PROTECTING OUR COMMUNITY

We have been working very hard to prepare to re-open for normal "routine" preventive eye care, taking every precaution to ensure the safety of everyone involved. We are pleased to announce as of Monday May 18th we'll be seeing patients for all types of eye care, including routine annual eye exams.

But, things will be very different than they were prior to the pandemic.

1. Our front door will be locked at all times. We will be allowing only 1 person at a time in the office and by appointment only, so please enter alone, or with no more than l other person accompanying you. Others may wait in the car.

2. Masks will be required for both patients and us while in our office.

3. Upon entering, we will be checking your temperature and screen you for COVID symptoms or possible exposure. If your temperature is 100 F or higher, or you have symptoms or may have recently been exposed to COVID, we will reschedule you.

4. We will need you to respect the 6 feet personal distancing while outside the exam room

5. We will have you wash your hands for 20 seconds or use hand sanitizer when you enter. We will be using hand washing and hand sanitizer constantly and will be disinfecting everything you and we touch. Please don't touch anything that isn't absolutely necessary.

6. For frame selection or picking out glasses, please let us help you, and don't just browse and try on frames by yourself. We have to disinfect the frames every time they are touched or worn, and we need to know which frames need to be disinfected.

We are doing all these things to protect you and all of our other patients as best we can. We will need and depend on your cooperation on this during this very difficult time. Doing so will protect your fellow patients-many of whom are at extremely high risk if they contract COVID - and to protect us. All healthcare providers are putting themselves in harm's way every day during this pandemic - the more we all cooperate and take appropriate precautions, the better off we all will be.

We are all in this together. Thank you for your patience, understanding, and cooperation.

Please stay safe.

Dr. Jim Hutchins and staff