Tracer Products says its Cobra-4 and Cobra-6 multipurpose borescopes feature interchangeable blue- and white-light LED flashlights that enable technicians to inspect and leak-check hard-to-see ...

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.

What is blue light? “All the light we see is made up of different wavelengths of light,” says Vivienne Sinh Hau, MD, an ophthalmologist at Kaiser Permanente in Riverside, California. “Certain ...