1. Context

The growing interest of scientific communities in the millimeter-wave (30 to 300 GHz) and submillimeter-wave (300 GHz to 10 THz) domains augurs well for the development of innovative applications in high-speed electronics and optics. In this context, terahertz spectro-imaging 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 more, the very high penetrating power of these waves makes it possible to visualize objects that are invisible on the surface, in volume or opaque in the visible. We propose to review the various approaches to tomographic imaging in the terahertz band. Physical and technological limitations will be discussed. Finally, illustrations in non-destructive...