Year: 2014
Type: conference-paper
Abstract: In recent years, new coronagraphic schemes have been proposed, the most promising being the optical vortex phase mask coronagraphs. In our work, a new scheme of broadband optical scalar vortex coronagraph is proposed and characterized experimentally in the laboratory. Our setup employs a pair of computer generated phase gratings (one of them containing a singularity) to control the chromatic dispersion of phase plates and achieves a constant peak-to-peak attenuation below 1:1000 over a bandwidth of 120 nm centered at 700 nm. An inner working angle of λ/D is demonstrated along with a raw contrast of 11.5magnitudes at 2λ/D. A more compact setup achieves a peak-to-peak attenuation below 1:1000 over a bandwidth of 60 nm with the other results remaining the same.
DOI: 10.1117/12.2054875
Authors: Ronnie Errmann, Stefano Minardi, Thomas Pertsch
Institution: Friedrich Schiller University Jena
Language: German
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2008536825