Visual acuity—the ability to discern letters, numbers, and objects from a distance—is essential for many tasks, from recognizing a friend across a room to driving a car. Researchers previously assumed ...

What does 20/20 vision mean? When you visit your doctor or an eye care professional, you may be asked to read an eye chart. You may be told you have normal 20/20 vision. What does that really mean? An ...

At least once in your life, you must have squinted at the eye chart at the doctor’s office or DMV, trying to make out the blurry bottom line. The test seems simple enough, right? Read a random string ...