Vision is a fundamental physiological function, allowing us to detect and interpret the surrounding environment. A variety of tests are performed in the health-care setting to assess eye function, including visual acuity and color vision. Use Wolfram|Alpha to interpret typical eyeglass prescriptions, including correction power measured in diopters, or explore how individuals with certain vision deficiencies see the world.
Visual acuity is the ability of the eye to perceive fine details. Normal visual acuity is indicated as 20/20, meaning that one can discern what a person with normal vision can see from a distance of 20 feet.
Color blindness is common, and there are different types of color vision defects. The vision deficiency simulator in Wolfram|Alpha helps you experience how people with a particular condition see normal color images.