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Ency. home > Test > V > Visual acuity

Visual acuity    See images

Overview | Risks | Results

Alternative names:

Vision Testing

Definition:

The visual acuity test measures the smallest letters that you can read on a standardized chart at a distance of 20 feet. 

How the Test is Performed

This test may be done in a health care provider's office, a school, a work place, or elsewhere. Stand behind a line 20 feet from the eye chart. Remove glasses or contacts. Keep both eyes open and gently cover one eye with the palm of your hand, a piece of paper, or a paper cup while you read out loud the smallest line of letters that you can read on the chart.

If you are not sure of the letter, you may guess. This is repeated with the other eye. Repeat the procedure while wearing glasses or contacts.

How to Prepare for the Test

Adults:
No special preparation is necessary for this test.

Children:
The physical and psychological preparation you can provide for this or any test or procedure depends on your child's age, interests, previous experiences, and level of trust. For specific information regarding how you can prepare your child, see the following topics as they correspond to your child's age:

How the Test will Feel

There is no discomfort.

Why the Test is Performed

The test is performed when there are problems or changes in vision. In children, the test is performed to screen for any visual problems.

Ency. home > Test > V > Visual acuity

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