Phase detection for continuous terahertz wave

In this paper we proposed a method of phase extraction for continuous terahertz wave. Firstly, we study the mathematical relationship of phase between the electro-optic sampling signal and terahertz wave in the theory, and then build the platform of continuous terahertz wave, using BWO as the source of terahertz radiation and Fs-laser as the detection of pulse. After using differential circuit and the principle of electro-optic sampling, we detect the polarization properties of optical signal and transform it into electric signal. With the filter amplifying circuit for signal processing, we obtain the phase of continuous THz wave at 0.2 THz. This method of phase extraction provides a potential way to the continuous THz wave coherent imaging, which is of great significance to the further study on continuous THz wave coherent imaging.