Laser Blast Makes Regular Light Bulbs Super-Efficient
guruevi writes with news that a process using an ultra-powerful laser can crank up the efficiency of everyday incandescent light bulbs. Using the same laser process covered several years ago, the tungsten filament has an array of nano- and micro-scale structures formed on the surface making the resulting light as bright as a 100-watt bulb while consuming less electricity than a 60-watt bulb and remaining much cheaper to produce. "The key to creating the super-filament is an ultra-brief, ultra-intense beam of light called a femtosecond laser pulse. The laser burst lasts only a few quadrillionths of a second. To get a grasp of that kind of speed, consider that a femtosecond is to a second what a second is to about 32 million years. During its brief burst, Guo's laser unleashes as much power as the entire grid of North America onto a spot the size of a needle point. That intense blast forces the surface of the metal to form nanostructures and microstructures that dramatically alter how efficiently light can radiate from the filament."
Laser Blast Makes Regular Light Bulbs Super-Efficient
So that whole time in Star Wars, they were just trying to make each other Super-Efficient? That's a whole lot nicer than what I was led to believe was initially going on.
LASIK makes a lot more sense now too.
I'm learning!
My work here is dung.
So, considering they are as cheap to produce as normal lightbulbs, we can expect to see these on the shelves in...2050?
But it doesn't matter (at least to those of us in the USA), because in 2014 incandescent bulbs will be banned.
End of lesson. You may press the button.
There's an app for that.
You don't seem to appreciate just how short a femtosecond is. As it is only 1e-15sec (1 millionth of a nanosecond), that means a pulse of 1e15W (1 million terawatts) would use only about 1 joule of energy.
So let's say for the sake of argument that the power and pulse length are both an order of magnitude larger. Then say it's only 10% efficient, so that the process actually takes 1kJ. This energy corresponds to all of 25 seconds at 40W. In other words, the break even lifetime is under one minute.