Lobsters see by reflection, not refraction. The reflection is made possible by thousands of squares located in the lobster's eyes, which are near the base of the antennae. These squares are the lobster's optics. Composed entirely of straight walls and right angles, as opposed to the human eye's curved rods and cones, a lobster's eye reflects the light beams that enter at standard, very shallow angles, or "grazing angles." The consistency of these angles of reflection allows the imaging system to send all of the beams reflected by a particular object (like potential prey on the ocean floor) to the same focal point.
A new scanner in development at Physical Optics Corporation and funded by the U.S. Department of Homeland Security incorporates a lobster's reflection-based eyesight. It's called the Lobster Eye X-ray Imaging Device (LEXID), and it replicates the crustacean's optical system to a relative tee. The device consists of a low-powered X-ray generator and an optics system. The optics system is made up of thousands of metallic, highly polished squares that reflect and align the X-rays as they pass through, headed toward an object of interest (like a point on the outside of a cargo container). The beams bounce off the walls of the squares in completely predictable angles, so the system can set them moving in parallel waves. The parallel emission of the rays allows them to strike a much smaller area all at the same time, making for deeper X-ray penetration.
Instead of detecting X-rays that pass through an object, LEXID detects rays that are scattered back to the device. The optics system acquires and focuses these back-scattered rays by collecting all of the reflected beams into one focal point, instead of analyzing divergent beams at different points in the system. The ability to focus all reflected light in a smaller area makes for a more precise sensory pick-up. It's a very efficient scanning system.
LEXID can see through concrete, wood and up to 3 inches (75 mm) of steel with ease -- if not with perfect resolution. The picture isn't high-def, but it's good enough to make out what's inside a cargo container. And, because the optics can focus the X-rays more efficiently, they can be lower-powered without sacrificing visual capacity. That means the scanner can be used on human beings much more safely than current systems. The radiation exposure is much lower.
But how does this affect the world's termite population? Read on to check out the brave new world of applications for lower-power, higher-efficiency X-ray technology.