The technology is so sensitive that it could be used to detect a 100W light bulb at a distance of 800,000 km: the distance of a journey to the Moon and back.
The non-intrusive screening method has been touted for use in detecting illegal border crossings. It could be used to detect if people are hiding in crates, and even if they are carrying any weapons.
Developed by teams at security firm Sequestim and Cardiff University, the high-precision scanners can create an image based on human body heat in real time.
"For truck scanning, this reveals people even if they are hiding inside a packing crate," said Dr Sam Rowe, one of the inventors from Cardiff University. "We can even detect the shadow of concealed weapons hidden beneath the clothes of people inside trucks."
According to Sequestim, the scanner uses Terahertz technology, and does not emit any radiation, making it "completely safe". The hardware is small enough to be concealed in a trailer or van, scanning vehicles up to 30 times faster than existing methods.
Scientists trialled the technology at Cardiff Airport in December, using it as a security scanner to locate threatening objects carried by passengers.
"The camera detects millimetre-waves, which are just like visible light but at a wavelength more than one thousand times longer," said Ken Wood, sales and marketing director of Sequestim. "Any items concealed beneath clothing show up very clearly as a shadow because the human body, by dint of its heat, acts like a light bulb at these wavelengths. Unlike the scanners currently in use, our system only needs a few seconds to do its work."
"We plan to make the world a safer place, but we will also make the security processes quicker and less of an imposition."
Last year E&T looked at whether existing technologies could be used at the Irish border after the UK leaves the EU.
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