Transmitted single frequency terahertz two-dimensional scanning imaging system is designed by LabVIEW. A terahertz source with a fundamental frequency of 140 GHz is selected to emit continuous terahertz waves. Call LabVIEW functions of translation stage driver and phase-locked amplifier to realize the point-by-point two-dimensional movement and amplitude data reading of terahertz signal of sample for imaging. Image reconstruction and gray processing are carried out for the location of samples and corresponding amplitude information. Design of terahertz 2D scanning imaging is achieved. In order to verify effectiveness and feasibility of the imaging effect of the system

two-dimensional imaging experiments are carried out on two samples

mesh steel plate and cross plate

using 140 GHz and triple frequency of 420 GHz as terahertz imaging source. The experimental results show that

the imaging resolution of the 420 GHz is higher. The imaging resolution is mainly related to the scanning step of the sample and the terahertz source wavelength.