1. Context

The scientific community's growing interest in the millimeter-wave (30 to 300 GHz) and submillimeter-wave (300 GHz to 3 THz) spectrum augurs well for the development of innovative applications in high-speed electronics and optics. However, this part of the spectrum remains relatively unexploited, mainly because the technology is very delicate and not always mastered. These developments and transfers to industry cannot be achieved without studying the electromagnetic behavior of the materials used at these extreme frequencies, and the validity of active imaging. In this context, terahertz spectro-imaging is the answer. It offers innovative optical contrast potential, sensitive to the vibrational and rotational levels of materials. The spectroscopic aspect in this frequency range can therefore lead to very broadband characterization and unique identification of materials or samples. What's...