Detection of polymer degradation and metal corrosion by terahertz imaging using a quantum cascade laser and a THz camera

Recently, THz waves with frequencies from about 0.1 to 10 THz have emerged as a new scientific tool. In this paper, feasibility of locating degraded portions in polymer-insulated power cables by THz waves has been examined, using a compact system consisting of a quantum cascade laser and a THz camera with uncooled microbolometers. The degradation we examined is oxidation of cross-linked polyethylene and rust on copper. As a result, we found that the compact system is capable of detecting polymer oxidation.