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.
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Explore optical properties of corrective lenses and interpret typical eyeglass prescriptions.
Get information about an eyeglass prescription:
Calculate the change in eyeglass prescription due to the tilt of lenses:
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.
Simulate a vision deficiency:
Get images of objects as seen through a dog's eyes.
Apply dog vision to an image: