An E Chart, also known as a Tumbling E Chart, is an ophthalmological

Ophthalmology

Ophthalmology is the branch of medicine that deals with the anatomy, physiology and diseases of the eye. An ophthalmologist is a specialist in medical and surgical eye problems...

 chart used to measure a patient's acuity for distant vision.

Uses

This chart is useful for patients that are illiterate or too young to read but who can speak.

It contains rows of the letter "E" in various kinds of rotation. The patient is asked to state where the limbs of the E are pointing "up, down, left or right." Depending on how far the patient can read his or her visual acuity is quantified. It works on the same principle as Snellen's distant vision chart

Snellen chart

A Snellen chart is an eye chart used by eye care professionals and others to measure visual acuity. Snellen charts are named after the Dutch ophthalmologist Herman Snellen who developed the chart during 1862...

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