Results from smartphone-based Snellen charts, which are eye charts used to measure visual acuity, are not consistent with results from standard Snellen visual acuity chart tests, according to a study ...

The term "20/20 vision" refers to how sharp your eyes are when you look at a standard eye chart (Snellen chart) from a distance of 20 feet (or 6 meters)—depending on where you live. In the United ...

Critics say Vision Research's tests are a waste of money. Florida taxpayers are paying millions of dollars for an Alabama company with a spotty track record to test the vision of hundreds of thousands ...