The direct-write technology for liquid-crystal patterns allows for manufacturing of extreme geometric phase patterned coronagraphs that are inherently broadband, e.g. the vector Apodizing Phase Plate (vAPP). We present on-sky data of a double-grating vAPP operating from 2-5 μm with a 360-degree dark hole and a decreased leakage term of ∼10−4. We report a new liquid-crystal design used in a grating-vAPP for SCExAO that operates from 1-2.5μm. Furthermore, we present wavelength-selective vAPPs that work at specific wavelength ranges and transmit light unapodized at other wavelengths. Lastly, we present geometric phase patterns for advanced implementations of WFS (e.g. Zernike-type) that are enabled only by this liquid-crystal technology.
@article{arxiv.1709.09897,
title = {Patterned liquid-crystal optics for broadband coronagraphy and wavefront sensing},
author = {David S. Doelman and Frans Snik and Nathaniel Z. Warriner and Michael J. Escuti},
journal= {arXiv preprint arXiv:1709.09897},
year = {2017}
}