Terahertz spectral imaging using correlation processing

Terahertz (THz) reflection spectroscopy has the potential to extract unique spectral signatures from various materials of interest, but these signatures can be distorted by rough surface scattering, low signal strength, and alignment errors. One method of addressing these challenges and increasing gain is to coherently combine information across frequency bands. This method, called correlation processing, uses both phase and magnitude information to provide concurrent 3D images and chemical mapping. This paper provides examples from pressed pellets that show the increased ability to distinguish materials with strong spectral signatures from other compounds.