Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
Definition
The Snellen chart is a tool used in eye examinations to measure visual acuity, featuring rows of letters that decrease in size. It helps determine the smallest letters a person can read from a standardized distance of 20 feet.
Related terms
Visual Acuity: The clarity or sharpness of vision, often measured by the ability to identify letters or numbers on a standardized eye chart from a specific viewing distance.
Optometrist: A healthcare professional who specializes in examining the eyes for vision and health problems and prescribing corrective lenses.
Nerves that emerge directly from the brain (including the optic nerve, involved in vision), part of what is assessed during a comprehensive neurological exam