We experimentally demonstrate a camera whose primary optic is a cannula/needle (
Over the last decade, the vector-apodizing phase plate (vAPP) coronagraph has been developed from concept to on-sky application in many high-contrast imaging systems on 8 m class telescopes. The vAPP is a geometric-phase patterned coronagraph that is inherently broadband, and its manufacturing is enabled only by direct-write technology for liquid-crystal patterns. The vAPP generates two coronagraphic point spread functions (PSFs) that cancel starlight on opposite sides of the PSF and have opposite circular polarization states. The efficiency, that is, the amount of light in these PSFs, depends on the retardance offset from a half-wave of the liquid-crystal retarder. Using different liquid-crystal recipes to tune the retardance, different vAPPs operate with high efficiencies (
- NSF-PAR ID:
- 10227783
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Applied Optics
- Volume:
- 60
- Issue:
- 19
- ISSN:
- 1559-128X; APOPAI
- Page Range / eLocation ID:
- Article No. D52
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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