Light-emitting diodes are front and center for many of our digital experiences. Every modern phone and tablet you look at uses LEDs in its display. It’s worth knowing how these work. In short, LEDs ...

They look otherworldly — like a Star Wars Stormtrooper’s helmet — and promise to give you clearer, smoother-looking skin. LED light masks are exactly what they sound like: devices illuminated by LED ...

At-home light-emitting devices are all the rage, promising Oscar-winning radiance, but do LED face masks really work or are they just sci-fi fantasy? And, are they safe? Consumer Reports sheds light ...