Non-phosphor white LED

Now, this is interesting.

Most of you know that white LEDs aren't actually white. They are a blue LED with a phosphor blend applied to downconvert the blue light to green, yellow, and red, producing what we see as white light. Well, there have been some attempts to create a white LED that doesn't use phosphors.


It's a bit of an old article, but it's interesting none the less, and begs the question if this is being persued today for white LEDs.

Without getting into the nitty gritty, the researchers basically modified the typical InGaN (Indium, Gallium, Nitride for those not in the know) structure of the LED by stressing it (creating voids in the indium layer). At low currents, the indium produces yellow light. As the current increases, blue light is created in the voids in the indium layer, and the effect of white light is created. The color temperature increases as the current increases. Sadly, the output is very low (at least when this article was released), and not much use for our reefs, but as an incandescent bulb replacement, it could be useful, and the shift in color temperature with current mimics the change in color temperature in incandescent bulbs.

Cool stuff.