Iterative design of multiple-input-single-output structures for THz signal multiplexing

Two different diffractive approaches for multiple-input-single-output design are presented and compared. The first one is obtained from the modified Ping-pong algorithm by enforcing two input sources and a single output spot. The second is combined from two separate structures (one for each input) to form a single element in the form of interlaced stripes. Designed structures have been simulated, manufactured by 3D printing, and experimentally tested.