Call it the fifth generation of light—the availability of electric lights that promote health and well-being by automatically mimicking the natural cycle of light. They switch between blue-rich ...

Light-emitting diodes (LEDs) are so ubiquitous that it's easy to forget just how much society relies on these underappreciated technological wonders. Yet, the history of the LED goes back further than ...

You’ve likely heard that blue light from smartphone screens may be keeping you awake at night. While the sun is our main source of blue light, the rise of LEDs and screen use exposes us to artificial ...

It’s hard to believe that the first blue LED didn’t arrive until 1993. They look simple, but looks are deceiving (Fig. 1). 1. Image showing a blue InGaN-based LED with gold wire contacts (0.4 × 0.4 mm ...

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