Towards real-time multi-spectral millimeter-wave imaging with dual frequency combs

Millimeter-wave and terahertz hyperspectral imaging is expected to play an important role in many applications, from industrial product inspection to security. However, current systems suffer from various limitations in different aspects of their performance that prevent them from having a noticeable impact on our lives. Here we present the first direct multi-spectral dual-comb imaging system operating in the millimeter-wave frequency range in which both spatial and spectral information are retrieved simultaneously. This technique can address many of the currently existing technological weaknesses by providing accurate and high-resolution spectral measurements, maximum adaptability for application-tailored operation and real-time operation capabilities. Several proof-of-concept demonstrations validate the instrument's ability to provide spectro-imaging characterizations on various materials with noteworthy performance levels.