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Updated: Apr 18, 2026
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Characterization of SiN Integrated Optical Phased Arrays on a Wafer-Scale Test Station
Published on: April 1, 2020
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Performance characterization of a broadband vector Apodizing Phase Plate coronagraph.
Optics Express
|January 22, 2015
Summary
A new vector-Apodizing Phase Plate (vAPP) coronagraph uses liquid crystals to suppress starlight, enabling clearer direct imaging of exoplanets. This advanced coronagraph offers broadband capabilities and improved contrast for planet detection.
Area of Science:
- * Astronomy and Astrophysics
- * Optical Engineering
Background:
- * Direct imaging of exoplanets is challenged by starlight suppression.
- * Coronagraphs are essential for blocking diffracted starlight.
- * Existing Apodizing Phase Plate (APP) coronagraphs have bandwidth and geometric limitations.
Purpose of the Study:
- * Introduce the vector-APP (vAPP) coronagraph for enhanced exoplanet detection.
- * Overcome limitations of classical APP coronagraphs.
- * Achieve broadband, high-contrast starlight suppression.
Main Methods:
- * Implemented vAPP using patterned liquid crystals for vector phase control.
- * Utilized beam-splitting based on circular polarization to create complementary point spread functions (PSFs).
- * Characterized vAPP performance through pupil-plane pattern reconstruction and PSF analysis.
Main Results:
- * Developed a prototype vAPP with a 500-900 nm bandwidth using liquid crystals.
- * Achieved a raw contrast of 10⁻³.⁸ between 2 and 7 λ/D over a 135-degree wedge.
- * Demonstrated vAPP's ability to reconstruct its optical properties and match PSF models.
Conclusions:
- * The vAPP coronagraph offers a manufacturable solution for high-contrast imaging.
- * Liquid crystal technology enables extreme phase patterns and broadband operation.
- * vAPP technology advances phase-manipulation coronagraphy for exoplanet discovery.
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