Imaging devices based on terahertz waves are most widely known for the bulky equipment use for security screening at airports. Terahertz rays also show promise for non-invasive imaging of human tissues, providing that difficulties in reproducing the curved contours of 3D objects are overcome.

Scan of a human hand as seen by the device.Researchers at Tokyo Institute of Technology used arrays of carbon nanotubes (CNTs) to design a terahertz scanning system that can image curved 3D surfaces.

The flexible scanner integrates 23 CNT detector elements into a portable, wearable device without the need for planar antennas since the CNT films absorb electromagnetic radiation over a broad terahertz range.

The device was used for active imaging of flat and curved samples, multiview scanning of cylindrical samples, and passive wearable imaging of a human hand (see video).

Applications are expected to include noninvasive inspections in pharmaceutics, food quality control, and medical monitoring.