Suppression of Laser Output Fluctuation in THz Scanning Transmission Imaging

THz laser can penetrate a wide range of materials which are opaque to visible and near infrared light. So THz imaging has been an important research direction nowadays. When using the THz imaging methods of point-by-point scanning transmission, the laser output power’s fluctuation has a big influence on the imaging quality, which is the main source of the imaging noise. In this paper, the influence of THz laser output power’s fluctuation on the imaging quality is analyzed. The homomorphic filtering algorithm is introduced to the transmission imaging model, which is used to estimate and suppress the noise. Also the average power in each row and the imaging model are used to reconstruct the image. The two methods above can achieve good results in the real THz image processing.