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arXiv · 1709.09897

Patterned liquid-crystal optics for broadband coronagraphy and wavefront sensing

David S. Doelman·Frans Snik·Nathaniel Z. Warriner·Michael J. Escuti
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Abstract

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 $\mu m$ with a 360-degree dark hole and a decreased leakage term of $\sim 10^{-4}$. We report a new liquid-crystal design used in a grating-vAPP for SCExAO that operates from 1-2.5$\mu m$. 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.

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David S. Doelman, Frans Snik, Nathaniel Z. Warriner, Michael J. Escuti. 2017-09-28. Patterned liquid-crystal optics for broadband coronagraphy and wavefront sensing. https://doi.org/10.1117/12.2273406

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