GCN LAB IMPRESSIONS
Army developing laser-guided lightning bolts
- By Greg Crowe
- Jul 02, 2012
Engineers at the Army’s Picatinny Arsenal in New Jersey have managed to send lightning bolts down a laser beam. And they didn’t even use The Force (as far as we know).
The idea of firing targeted lightning bolts — in this case, a short 500 billion-watt burst of optical power — has been a staple of science fiction fantasies, but has been out of the reach of anyone in the real world. The Laser-Induced Plasma Channel, LIPC, could change that.
Light travels more slowly in a gas (such as our atmosphere) than in a vacuum, and gets even a little slower when the beam pulses more intensely. If the pulses are intense enough, the power output of the laser beam increases to the point that it ionizes the air surrounding it, turning it into plasma.
This sheath of plasma conducts electricity far better than the surrounding, ionized air. So a high-voltage current can be sent along the path of the laser beam and into the beam’s target. To think that people get paid to think this stuff up.
This can have many applications. Most notably, and I hope the first thing they put this to use for, it could be used to detonate unexploded devices (such as land mines or IEDs) safely from a distance. As long as the target conducts electricity better than the ground it’s sitting on, the current caused by the beam will cause it to detonate pretty reliably.
I know you’re thinking, well, why not use this application of technology to beam power everywhere? Well, a couple of things.
First, it would take a great deal of power to have a laser beam constantly ionize the surrounding air. Second, there would be nothing to stop the ionization from occurring inside a lens, or within the amplification device, so they have to send pulses down the laser beam so the electricity goes where they want it.
So, I think for now we will have to stick to the wireless power technology we have available.
A few things have to be accomplished before this can be ready for operational use in the field. Synchronizing the laser pulse with the high voltage is currently tricky at best. Also, many of the components need to be ruggedized to survive combat conditions.
But hopefully someday soon we will see it in use, saving the lives of many of our soldiers by making bomb disposal safer. You can use your imagination to figure out other potential uses.
Greg Crowe is a former GCN staff writer who covered mobile technology.