Advances in Terahertz Imaging

  • Arijit SahaEmail author


Since the discovery of photography in the mid-1820s, imaging technology has moved far beyond the visible wavelength range. On one hand x-ray radiography is such an imaging technique which uses subatomic wavelengths, whereas on the other hand radars employ waves with wavelengths of several metres. However, it is seen that in last several years the field of terahertz imaging technology has become an area of interest, due to its various advantages. Actually discovery of new technologies in generation and detection of terahertz radiation have revolutionized this field. Promising applications for terahertz imaging, spectroscopy and sensing have generated much of this interest. By terahertz, generally the electromagnetic spectrum within frequency range of 0.1-10 THz is meant, which corresponds to 3000-30 μm. Terahertz waves are non-ionizing and non-invasive and hence have no risk for living organisms. Also they can provide images which are comparable to x-ray images. Though some of the techniques of THz imaging have been borrowed from well-established techniques like x-ray computed tomography, synthetic aperture radar etc., but several techniques have been exclusively developed for terahertz imaging. Compared to microwaves the THz radiation has much smaller wavelengths and thus provides higher image resolution. However, due to long wavelengths of THz radiation compared to visible wavelengths, far-field imaging using THz radiations has low resolution compared to optical systems. It is found that THz imaging has tremendous potential in applications like security screening, inspection of foods, inspection of semiconductors, pharmaceutical inspection, 2D and 3D imaging, including medical diagnosis to name a few.


THz-TDS Reflection spectroscopy Transmission spectroscopy THz pulsed imaging 


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Copyright information

© Springer Nature Singapore Pte Ltd. 2020

Authors and Affiliations

  1. 1.Department of Electronics and Communication EngineeringB. P. Poddar Institute of Management and TechnologyKolkataIndia

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