Bright idea

WorldChanging mentions a new, simpler approach to making white-light (as opposed to single-wavelength) LEDs using very small (smaller than the wavelength of light!) cadmium selenide crystals. Similar crystals could also be used to absorb sunlight in photovoltaic systems. According to Vanderbilt's press release: The white-light quantum dots, by contrast, produce a smoother distribution of wavelengths in the visible spectrum with a slightly warmer, slightly more yellow tint, reports Michael Bowers, the graduate student who made the quantum dots and discovered their unusual property. As a result, the light produced by the quantum dots looks more nearly like the “full spectrum” reading lights now on the market which produce a light spectrum closer to that of sunlight than normal fluorescent tubes or light bulbs.