The key point to measure a sample and to carry out its absorption spectrum is that the whole test process is completed in very stable situations. Although the distributed setup of THz-TDS is flexible to implement kinds of experiments, slightly displacements of mirrors may occur in the system. A typical kind of disturbance exists in the system due to shifts of mirrors and accumulation of static charges in THz switch or detector, particularly in a long term test. The resulting of the disturbance is that a deviation is involved in the THz pulse. Furthermore, due to the sample and reference can't be tested simultaneously, the sample's absorption spectrum maybe goes down to negative values at some frequencies. A recovery algorithm is presented to overcome the disturbance. Some examples validate the effects of the algorithm.

Date Published: 13 March 2012
PDF: 6 pages
Proc. SPIE 8330, Photonics and Optoelectronics Meetings (POEM) 2011: Laser and Terahertz Science and Technology, 833005 (13 March 2012); doi: 10.1117/12.920957

Published in SPIE Proceedings Vol. 8330:
Photonics and Optoelectronics Meetings (POEM) 2011: Laser and Terahertz Science and Technology
Jianquan Yao; X. C. Zhang; Dapeng Yan; Jinsong Liu, Editor(s)