Preferably, doctors and airport security personnel would scan your body with devices that balance difference, resolution and penetration ability—and that don’t kill you after protracted contact. And while X-rays do a pretty good job, a new moveable scanner for medical imaging and refuge screening suggests we may soon have a better option: T-rays.

Terahertz radiation is a band that lies between microwaves and infrared, with a short wavelength that gives it better declaration than microwave imaging. critically, it also carries much a smaller amount energy than X-rays. “It’s a form of ‘non-ionizing’ emission, which means it doesn’t have sufficient energy to thump an electron off when it hits an atom,” explains Ulrich Whelp, a materials scientist at Argonne National Laboratory. That wholly eliminates the long-term cancer risk associated with X-rays, he says.

Whelp and his team, along with scientists from Turkey and Japan, used high-temperature superconductors to build a small prototype T-ray generator. The machine uses a small booming hollow to amplify the T-ray signal; similar to the way laser light is generated, rising hopes that that making of a moveable, battery-powered T-ray producer might not be far rotten.

The imaging properties of T-rays are slightly different than X-rays. T-ray can pass through garments and packaging just fine, but they are blocked by water, which means they can only go through about 1/4 in. deep into human bodies. This makes them ideal for skin-cancer performance and tooth-cavity detection, an submission already being pursued by Rearview, a T-ray spin-off from the University of Cambridge in Britain.

Though, existing T-ray generators are still too heavy for practical use, Welp notes: “They’re very big, and the powers they create tend to be small.” The new superconducting producer is much smaller, even though it necessitates a portable cooler to keep the superconductor colder than about minus 300 F. However, the power output remains small—less than a microwatt—and the next challenge for researchers is to add to that to practical power levels of close to a mill watt.

In the intervening time, X-rays aren’t dead just yet. Much like customer cameras earlier in the decade, X-ray imagers are slowly moving from film to digital—and the new flat-panel LCD X-ray detector that Samsung make public last week, with ultra-high 9.4-megapixel meaning, might induce a few geeky doctors to upgrade their imagers.