Terahertz light beam expansion uniformizing device

The invention relates to a terahertz light beam expansion uniformizing device. The front end of the uniformizing device is provided with a terahertz light source, and the uniformizing device further comprises a light expander, an integrator and an imaging focal plane, the beam expander is arranged between the terahertz light source and the integrator, the focal plane is arranged behind the integrator, the light expander comprises a second convex lens and a first convex lens between the second convex lens and the terahertz light source, the integrator comprises two lens arrays, a lens and a condensing lens, the two lens arrays are fixedly arranged in the front and back sides of the lens respectively, the lens is arranged in front of the condensing lens, the imaging focal plane is arranged at the real focal point of the condensing lens, and the photocenters of the first and second convex lenses and the condensing lens and the center of the terahertz light source are in the same straight line. The terahertz light beam expansion uniformizing device is simple in structure, and can be used to obtain large-area flat terahertz light spots with uniform energy distribution.