High-contrast imager for Complex Aperture Telescopes (HiCAT): 3. first lab results with wavefront control

Abstract

HiCAT is a high-contrast imaging testbed designed to provide complete solutions in wavefront sensing, control and starlight suppression with complex aperture telescopes. The pupil geometry of such observatories includes primary mirror segmentation, central obstruction, and spider vanes, which make the direct imaging of habitable worlds very challenging. The testbed alignment was completed in the summer of 2014, exceeding specifications with a total wavefront error of 12nm rms over a 18mm pupil. The installation of two deformable mirrors for wavefront control is to be completed in the winter of 2015. In this communication, we report on the first testbed results using a classical Lyot coronagraph. We also present the coronagraph design for HiCAT geometry, based on our recent development of Apodized Pupil Lyot Coronagraph (APLC) with shaped-pupil type optimizations. These new APLC-type solutions using two-dimensional shaped-pupil apodizer render the system quasi-insensitive to jitter and low-order aberrations, while improving the performance in terms of inner working angle, bandpass and contrast over a classical APLC.

12 pages, 10 figures, Proceedings of the SPIE, Volume 9605, id. 96050I 12 pp. (2015)

References in corpus (5)

• Wide-Field InfrarRed Survey Telescope-Astrophysics Focused Telescope Assets WFIRST-AFTA 2015 Report
• Theoretical Limits on Extrasolar Terrestrial Planet Detection with Coronagraphs
• Apodized Pupil Lyot Coronagraphs for Arbitrary Apertures. IV. Reduced Inner Working Angle and Increased Robustness to Low-Order Aberrations
• High-contrast imager for Complex Aperture Telescopes (HiCAT): 1. Testbed design
• Deformable mirror interferometric analysis for the direct imagery of exoplanets

Cited by in corpus (10)

• Active correction of aperture discontinuities - optimized stroke minimization II: optimization for future missions
• Active correction of aperture discontinuities - optimized stroke minimization I: a new adaptive interaction matrix algorithm
• High-contrast imager for complex aperture telescopes (HiCAT): 5. first results with segmented-aperture coronagraph and wavefront control
• Capabilities of ACAD-OSM, an active method for the correction of aperture discontinuities
• High-contrast imager for complex aperture telescopes (HiCAT): 8. Dark zone demonstration with simultaneous closed-loop low-order wavefront sensing and control
• Experimental validation of active control of low-order aberrations with a Zernike sensor through a Lyot coronagraph
• High-contrast imager for complex aperture telescopes (HiCAT): 11. System-level demonstration of the Apodized Pupil Lyot Coronagraph with a segmented aperture in air
• Correcting for the effects of pupil discontinuities with the ACAD method
• Dark zone maintenance results for segmented aperture wavefront error drift in a high contrast space coronagraph
• Estimating low-order aberrations through a Lyot coronagraph with a Zernike wavefront sensor for exoplanet imaging