Tom Nugent, president of LaserMotive, shows us an example of his company's laser power beaming technology, which transmits energy with lasers instead of wires. The demo involved a micro-helicopter flying with no batteries on board. The system would fly for at most 10 minutes with batteries, but powered by a laser, it can fly all day long without ever needing to land.
Nugent walks us through how the system works... A diode laser puts out somewhere in the range of 10 to 15 W of near-infrared light, which is then expanded and collimated by an optics train (behind laser safety glass). The beam hits some specialized photovoltaics on the bottom of the helicopter, which are hardwired into the helicopter's motor. If the laser is turned off, the motor stops, and the helicopter falls out of the sky. When the laser is turned back on, the helicopter takes right off again.