What is the Feinbloom chart used for?

• A. Diagnosing glaucoma
• B. Evaluating color vision
• C. Very poor acuity, and patients that have difficulty with eccentric viewing
• D. Measuring visual field

Answer: (D)

The Feinbloom chart is a low-vision acuity measure designed for people with very poor vision who often rely on eccentric viewing. Its letters are large and high-contrast, so individuals with limited central vision can still identify shapes and read enough to estimate their functional acuity. This makes it especially useful when standard charts (like Snellen) can’t be read, helping clinicians quantify acuity for planning rehabilitation, magnification needs, and goals. It’s not used to diagnose glaucoma, not a test of color vision, and not a measure of the visual field; those functions are assessed with other tools.