Fast thickness measurement based on high-speed broadband terahertz frequency sweeping

Recently, we reported an experimental implementation of THz frequency sweeping with a kHz sweep rate and a THz sweep range using a wavelength-swept laser and a distributed feedback laser in THz photomixing. Frequency-domain THz interferograms can be rapidly measured by combining the THz frequency sweeping and coherent homodyne detection. We present fast thickness measurement based on this measurement method.