A purple wave of faulty streetlights has swept across the USA, generating incorrect theories, bad lighting and fans of an accidental aesthetic.

In this method, the blue LED is used in conjunction with a yellow phosphor coating. The idea is to have part of the blue light converted into yellow light and leave a part of it in its original ...

or use a blue LED and cover it with yellow phosphor that filters blue wavelengths and ultimately produces a bright white light. The thickness of that layer determines the warmth of the light ...

The advantage to using a blue LED and a yellow phosphor is its high theoretical efficacy, which is attractive for the creation of a cheap, bright white-light source. However, this benefit comes at ...

"When the electricity flows, light is emitted directly from the surface of the LED," McGowan says. The coating on the LED, called a phosphor, can be manipulated to produce white light or colors by ...

What color are the street lights in your town? While an unfortunate few still suffer under one of the awful colors offered by vapor discharge lamps, like the pink or orange of sodium or the ...