Seen here is a quadrocopter, a small helicopter powered by beamed lasers. It was said to set a world record by staying aloft for more than 12 hours.

Law enforcement officials may be able to monitor crowds with low-flying cameras for more than 12 hours, thanks to what could be record-breaking laser beam-powered technology.

Two companies, Germany's Ascending Technologies and Seattle's LaserMotiv, say they set a new standard for flying time for what's called a quadrocopter, a small electric-powered helicopter.

While the concept of a camera mounted on a quadrocopter has been around for some time, the companies said in a release today that until now, law enforcement had not been able to use them for more than 20 minutes.

But Ascending Technologies and LaserMotiv say they fashioned a 1-kilogram quadrocopter called the "AscTec Pelican," which was powered by a laser beam and special photovoltaic cells and was able to stay aloft for about 12 hours and 27 minutes.

The principle behind the laser and photovoltaic cells is known as power beaming, and in this manifestation of the technology, the two companies set up a directed laser beam and coordinated it with a high-speed tracking system that is designed to power objects like a quadrocopter over distances of up to several kilometers. The AscTec Pelican was also outfitted with a battery pack that allowed the quadrocopter to fly autonomously for up to five minutes.

This technology is similar to one being proposed by a start-up known as Escape Dynamics--albeit at a much different scale. Escape Dynamics hopes to be able to power a full-scale rocket launch with ground-based beamed microwaves within 7 to 10 years. The system being used by Ascending Technology and LaserMotiv is obviously much less ambitious, though it is already working today. Indeed, the companies said that LaserMotiv was the winner of a 2009 NASA-sponsored contest known as the Power Beaming Competition.