Molter, DanielDanielMolterTrierweiler, ManuelManuelTrierweilerEllrich, FrankFrankEllrichJonuscheit, JoachimJoachimJonuscheitFreymann, Georg vonGeorg vonFreymann2022-03-132022-03-132016https://publica.fraunhofer.de/handle/publica/39475710.1109/IRMMW-THz.2016.7758584Terahertz time-domain spectroscopy relies on the knowledge of the time delay between two ultrashort laser pulses. This time delay is most commonly introduced by mechanically driven delay lines, where often a linear movement or in the case of oscillation based devices a sinusoidal movement is assumed or measured only imprecisely. We present a highly accurate method to measure the real time delay by overlapping the ultrashort pulse with one optical branch of a Mach-Zehnder interferometer. The interferogram provides an exact time base for the terahertz signal and enables high-precision time-domain spectroscopy even with inherently highly inaccurate delay lines.enTerahertz SpectroscopyDelaysMach-Zehnder InterferometerOptical Delay Lines621conference paper