Terahertz (THz) radiation is used today most prominently for security screening at the airport. It’s the machine you stand in with your hands up as it swings its scanning arms in front and behind you. In medicine, terahertz imaging has the potential to help diagnoze certain types of cancer and to monitor a variety of health parameters to aid in assessment of overall health. Because of the extremely short length of terahertz waves, this imaging modality has a lot of limitations, including shallow penetration into tissues, and that prevents it from being used more widely. Yet, since it’s non-ionising, it’s probably safe and may even replace dangerous X-rays for some applications.
Currently, terahertz imaging is very poor at scanning curved surfaces even though it can peer a few millimeters deep into some tissues. To overcome this, researchers at Tokyo Institute of Technology have developed a flexible and even wearable terahertz scanner that can image curved 3D surfaces such as our skin.
Made of 23 carbon nanotube detectors that work as a unified imaging array, their device can be wrapped around a finger, for example. Because carbon nanotubes are able to absorb a wide range of terahertz radiation, there’s no need for planar antennas.
Here’s one of the researchers behind the new technology explaining how it works:
From the study abstract in Nature Photonics:
We achieved room-temperature THz detection over a broad frequency band ranging from 0.14 to 39 THz and developed a portable THz scanner. Using this scanner, we performed THz imaging of samples concealed behind opaque objects, breakages and metal impurities of a bent film and multi-view scans of a syringe. We demonstrated a passive biometric THz scan of a human hand. Our results are expected to have considerable implications for non-destructive and non-contact inspections, such as medical examinations for the continuous monitoring of health conditions.
Study in Nature Photonics: A flexible and wearable terahertz scanner…