System construction and imaging experiment of a focused 300G terahertz FMCW systems

Abstract

We built a 300G terahertz (THz) frequency modulated continuous wave(FMCW) imaging system. This paper describes the construction and imaging experiment of a FMCW system with a sweep bandwidth of 275~325GHz. Quasi-optical module of the system can focus the spot radius of the system from 16.35 mm to 7.61 mm. The signal-to-noise ratio and resolution of the system were greatly improved. At the same time, the cage structure design of industrial application-grade lens group is implemented, which greatly increases its applicability. We conducted both one-sided and three-dimensional imaging experiments on the built imaging experimental system. The results show that the resolution of the designed imaging system can reach 3 mm, which is of tremendous value for the application of THz nondestructive testing.