November 19, 2005

Butterfly wings that are "identical in design to the LED."

BBC reports:
This slab of hollow air cylinders in the wing scales is essentially mother nature's version of a 2D photonic crystal.

Like its counterpart in a high emission LED, it prevents the fluorescent colour from being trapped inside the structure and from being emitted sideways.

The scales also have a type of mirror underneath them to upwardly reflect all the fluorescent light that gets emitted down towards it. Again, this is very similar to the Bragg reflectors in high emission LEDs.

"Unlike the diodes, the butterfly's system clearly doesn't have semiconductor in it and it doesn't produce its own radiative energy," Dr Vukusic told the BBC News website "That makes it doubly efficient in a way.

"But the way light is extracted from the butterfly's system is more than an analogy - it's all but identical in design to the LED."...

"When you study these things and get a feel for the photonic architecture available, you really start to appreciate the elegance with which nature put some of these things together," he said.
No, I'm not trying to restart the Intelligent Design debate. I just think it's cool.


Paul said...

Definitely cool. Even more amazing when you stop to think these butterflies start life as caterpillars. Mind-boggling.

PatCA said...

Very cool, and humbling. Maybe the reason we "discovered" LED technology was that it works, and has worked for millions of years, in nature.

The insect world is waaay ahead of us. Who again is at the top of the evolutionary dogpile? :)

amba said...

Did the inventor(s) of LED study the butterfly wing, or is it independent discovery?

ATMX said...

This is an poorly written and titled article that is extermely misleading. The butterfly wings don't work like LEDs. LEDs (light emitting diodes) are electrically power semiconductor devices that generate light. The wings do not generate light in the same manner, as the light emission requires external ultraviolet light to excite fluorophores in the wing. What is special about the wings is the microstructure of the fluorescent part of the wings directs light out of the structure that would in a directional manner reducing light losses from nondirectional emission and absorption in the wing. This is apparently similar to the physical structure that the MIT team used to increase the amount of light that escapes the diode, but has nothing to with the diode itself. Diode technology was discovered decades ago, and has little to do with any natural biological phenomenon that I am aware of.

This article seems to be a puff piece by the BBC promoting the work (which is admittedly interesting) of some British scientists in a British science journal (which is admittedly one of the top two science journals in the world).

Greg D said...

Given the order of operations (after all, the butterfly came first), shouldn't the claim be that high-output LEDs act like butterflies?