Light fantasticThe 60W bulb has had its day. Welcome to the age of the 'white' LED. It's more efficient, it lasts longer and its price is falling rapidly. Charles Arthur tests a bright young thing 12 November 2003 Here's a conundrum: how can a product that can't emit white light produce white light? Answer: by cheating a little. That's the technique behind the new "white light" LEDs (a slight tautology, as LED stands for "light-emitting diode") that are now appearing in lights overhead and, if you're feeling flush, in torches near you. And if you're wondering why you should care...