...A completely novel invention, called a Photonic Fence, detects mosquitoes flying at a distance and shoots them down with lasers. Although this approach may sound high-tech (and indeed some of the inventors are veterans of the antiballistic missile program), the basic components needed for such a system largely exist already in inexpensive consumer electronics, such as laser printers, Blu-ray disc writers, camcorders, and video game consoles. The working prototype at Intellectual Ventures Lab was constructed almost entirely from parts purchased second-hand on eBay and similar websites.
The system would create a virtual fence made out of light— we call it a “Photonic Fence.” Light Emitting Diode (LED) lamps on each fence post would beam infrared light at adjacent fence posts up to 100 feet (30 meters) away; the light would then hit strips of retroreflective material (similar to that used on highway signs) and bounce straight back toward the illuminator. A camera on each fence post monitors the reflected light for shadows cast by a hapless insect flying through the vertical plane of light.
When an invading insect is detected, our software identifies it by training a nonlethal laser beam on the bug and using that illumination to estimate the insect’s size and also to measure how fast its wings are beating. Using this method, the system can not only distinguish among mosquitoes, butterflies, and bumblebees, but it can even determine whether a mosquito is male or female! (Females are significantly larger than males and have slower wingbeats.) This is useful because only female mosquitoes bite humans.
Our software is able to track a mosquito in flight once it establishes that it is a valid target. After running safety checks to ensure no unintended object is in view, the system activates a second, more powerful laser that zaps the mosquito, causing death either by damage to its DNA (an unconfirmed hypothesis) or by overheating. The energy levels and light frequencies used are not capable of damaging human tissue, but even so, we’ve built in safeguards that ensure that the system doesn’t fire when anything much larger than a mosquito is in the photonic fence.