It’s not quite the enemy.By Alex Schwartz

Blue light glasses claim to block wavelengths of light that are harmful to our eyes—but how harmful is that light to begin with?

The latest trend in eyewear is actually to see less—by filtering out certain parts of the visible light spectrum, particularly blue light. Countless brands offer supposed blue light-blocking glasses, mainly to folks who spend most of their days looking at screens. These products are cheap and you can even get them without a prescription, though at some eyewear outlets you can opt to have this coating added to your prescription lenses. Whatever the method, these glasses bank on the idea that blue light is harmful to our eyes. The only problem is, no one’s really sure that’s true.

Blue light, which makes up the highest-energy portion of the visible light spectrum, has shorter wavelengths than low-energy red light. These two wavelengths, and everything in between, is what the human eye can register as color. But there’s a lot more light beyond this spectrum that we can’t see. Ultraviolet (UV) radiation, for example, exists past the blue end of the spectrum, and is known to cause some nasty eye conditions like cataracts and macular degeneration with overexposure—that’s why we wear sunglasses when we’re outside….

Read more: https://www.popsci.com/blue-light-blocking-glasses-science#page-2

Source: Popular Science

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