What does a visual acuity measurement primarily assess?

• A. The ability to read letters on a chart at a specific distance
• B. Color vision
• C. Intraocular pressure
• D. Depth perception

Answer: (A)

Visual acuity measures how clearly the eye can resolve fine detail. A test for this purpose asks you to read letters or symbols on a standardized chart from a fixed distance, determining the smallest details you can reliably identify. This focuses on sharpness of vision at distance, not on color vision, eye pressure, or depth perception. Color vision is tested with color plates, intraocular pressure with tonometry, and depth perception with stereo tests that assess three-dimensional judgment. The acuity score (like 20/20) reflects what a person can see at the chart distance compared to a person with normal vision, and is typically performed with or without correction at a standard distance.