THz non-destructive evaluation using correlation processing

Terahertz (THz) has been well known for its unique ability to propagate through non-polar packaging material. At the same time, THz wavelengths are small enough to provide meaningful imaging resolution, leading to their large potential in non-destructive evaluation. Correlation processing is a technique that has been shown to detect phase resonances in illicit chemicals, and in this paper, is extended to detect defects in a device with THz reflection data. A small diagonal crack in a solar panel is used to demonstrate this new technique.