Blue light has a powerful effect on your body clock, ... It changes the background from white to black. Install blue light-filtering apps on smartphones, tablets, and computer screens.

Key Background. Blue is one of seven colors in the visible light spectrum. ... Blue light glasses are made to block and filter out blue light, reducing its potentially harmful effects.

Blue light usually comes from the sun but also from digital screens and LED lights. Some experts believe artificial sources may be causing eye damage in humans, but animal studies are inconclusive.

Think blue light is hurting your sleep cycle? A new study suggests it can actually improve the overall sleep quality of older adults — but only if they time it right.

Adding a blue light-filter to your eyeglasses won’t ease computer eye strain or protect your sleep, according to a new review, but other actions can help.