ABSTRACT
Imaging is generally understood as the measurement and replication of the intensity distribution of an active source emitting an electromagnetic wave or the backscattering profile of a passive object or scene [1]. The functionality of imaging can be greatly extended by incorporating spectroscopic techniques in the imaging system. For example, organic functional groups in the specimen can be identified and imaged by their select pattern of absorption wavelength [2]. Depending on what electromagnetic radiation is employed, imaging has been historically categorized as microwave imaging or optical imaging. The application of microwave and optical imaging to basic research and everyday life situations has been extremely successful. Compared with the long history of microwave and optical imaging, terahertz (THz) wave imaging based on optoelectronic THz time domain spectroscopy is in its infancy, emerging only in 1995 [3].
