Northwestern Engineering’s Cheng Sun and his team have used metamaterials and 3D printing to develop a novel lens that works with terahertz frequencies. It has better imaging capabilities than common lenses and opens the door for more advances in the mysterious realm of the terahertz. “Terahertz is somewhat of a gap between microwaves and infrared,” says Sun. “People are trying to fill in this gap because this spectrum carries a lot of information.” Terahertz scanners can discover concealed weapons, biological weapons such as anthrax, and plastic explosives. The lens was manufactured with a 3D printing technique called projection micro-stereo-lithography. The technique enables a scalable, rapid, and inexpensive way to produce the tiny features that are needed for the lens to operate at the terahertz frequency band. The printing technology allowed the researchers to fabricate the metamaterial to precisely fit their designs. In this video, Sun’s team prints a stent with the same technology used to print the terahertz lens.