Figure 5
From: Massive individual orbital angular momentum channels for multiplexing enabled by Dammann gratings
Principle of DOVG for OV beam combination and detection. (a) A Gaussian beam with a planar phase front is diffracted and encoded into OAM states by the DOVG. (b) Gaussian beams incident from the diffraction angles are combined into an OV beam with multiple OAM states in the zeroth order direction. (c) An OAM beam is diffracted and converted back into a Gaussian beam in the corresponding direction by an identical DOVG. DOVG, Dammann optical vortex grating; OAM, orbital angular momentum; OV, optical vortex.
