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How do glasses help us see?
Today, glasses help millions of people with poor vision be able to see clearly. But how? Andrew Bastawrous and Clare Gilbert help unravel the answer by explaining refraction — the ability of a transparent medium, like glass, water, or the eye, to change the direction of light passing through it.

What are those floaty things in your eye?
Sometimes, against a uniform, bright background such as a clear sky or a blank computer screen, you might see things floating across your field of vision. What are these moving objects, and how are you seeing them? Michael Mauser explains the visual phenomenon that is floaters.

Additional references

The Claim: Sitting Too Close to the TV Is Bad for Your Eyes - The New York Times
It was more than 70 years ago that television sets first went on sale in the United States, and perhaps it was just as long ago that a cautious mother, noticing a son or daughter propped in front of that mesmerizing new invention, snapped and barked the words that generations of children would grow up hearing: "Don't sit so close; you'll ruin your eyesight!" Now, scientists can say with certainty that the age-old warning is outdated.

Does Sitting Too Close to the TV Really Ruin Your Eyesight? - LiveScience
The myth got its start in the late 1960s, when General Electric sold television sets that emitted levels of radiation as much as 100,000 times more than what federal health experts considered safe. To its credit, GE quickly recalled and repaired its hazardous TVs. But there was a danger even before GE's big blunder.

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