But infrared light is invisible to the human eye, and not useful for any sort of indication or lighting. The first visible-spectrum LED ... anyone from building a white LED was putting all these ...

For white light, however, two or more wavelengths are required to generate a broad spectrum of light ... photonic crystals into the LED 15. White-light sources based on LEDs have a promising ...

Blast a high-intensity monochromatic laser down one end, and white light comes ... visible spectrum. It’s great to see projects like this that leverage low-cost, easy-to-source equipment to ...