We discuss the potental use of spatial mode sorters as coronagraphs capable of operating near the fundamental limits at small inner working angles.
Spatial mode sorter coronagraphs
Joel Carpenter, Nicolas K. Fontaine, Barnaby R. M. Norris, and Sergio Leon-Saval
https://doi.org/10.1364/CLEOPR.2020.C...
Laguerre-Gaussian coronagraph
Joel A. Carpenter, Nicolas K. Fontaine, Sergio G. Leon-Saval
https://doi.org/10.1117/12.2560588