Comment Already done. Nearly 20 years ago. (Score 1) 559
The reason this works is that the surface is modified at the nanoscale to suppress emissions in the infrared spectrum where most of the energy of an incandescent light bulb is wasted. Guess what? This has already been done nearly 20 years ago.
U.S. Patent 5,123,868 describes a filament with nanoscale tuned resonant cavities that suppress the emission of infrared. No fancy femtosecond lasers - it was manufactured using centuries-old metalworking techniques of repeatedly drawing wires to make them thinner, followed by acid etching. It works. It improves the efficiency about twofold. Unfortunately, nanostructures can't withstand these high temperatures very long, even when made of tungsten. They deteriorate in less than 100 hours and efficiency drops to that of a conventional bulb. I'm pretty sure happens here, too.