Figure 2
From: A compact diffractive sorter for high-resolution demultiplexing of orbital angular momentum beams
Schematic of the compact high-resolution sorter. The input OAM beam impinges on the outer annular region (A) of the diffractive optics that encodes the fan-out focusing unwrapper. Subsequently, a mirror reflects the beam towards the optical element again through its inner zone (B), where double phase-correction is performed. A Fourier lens completes the demultiplexing. A beam-splitter (BS) is used to separate input and output beams.
