A priori Information and Off-axis Measurement in Terahertz Tomography

By means of ray tracing, we incorporate a priori information about the sample geometry in the reconstruction process of terahertz computed tomography to improve imaging performance. We acquire radiation diverted by the sample instead of considering only transmission data from straight beam paths. The additional data and the beam path simulations are taken into account in an iterative two-step reconstruction process. To test the developed method experimentally, measurements on two representative samples are performed and evaluated.