The LED-crazed kids at Rensselaer Polytechnic Institute are at it again. In a paper published in this week's Science, they talk about how LED's not only will save huge amounts of energy (they don't yet but theoretically can) but can be used in much more sophisticated ways. Because different colours can be so easily mixed, they see opportunities galore:
-lights that change colour through the day to adjust to our bodies circadian rhythm-"According to a basic physics definition, this light has a high color temperature, while evening light has a far lower color temperature. Lighting that offers the ability to adjust color temperature could benefit human health, mood, and productivity"
-brake lights that can communicate with the brakes of the car following too closely;
-controlling the spectral composition of grow lamps to improve the out-of-season production of fruits and vegetables. (and will be a hit in head shops)
They admit that there is a lot of work to be done, and LED's in other frequencies have to be developed. (Read Wired here about the backlash against blue LED's) nonetheless, people have not rushed to changing to compact flourescents because they are not an improvement over incandescents functionally (if cost of operation is not relevant to you). LED's offer the possibility of being a dramatic functional improvement. ::PhysOrg