High-contrast imager for Complex Aperture Telescopes (HiCAT): 1. Testbed design

Abstract

Searching for nearby habitable worlds with direct imaging and spectroscopy will require a telescope large enough to provide angular resolution and sensitivity to planets around a significant sample of stars. Segmented telescopes are a compelling option to obtain such large apertures. However, these telescope designs have a complex geometry (central obstruction, support structures, segmentation) that makes high-contrast imaging more challenging. We are developing a new high-contrast imaging testbed at STScI to provide an integrated solution for wavefront control and starlight suppression on complex aperture geometries. We present our approach for the testbed optical design, which defines the surface requirements for each mirror to minimize the amplitude-induced errors from the propagation of out-of-pupil surfaces. Our approach guarantees that the testbed will not be limited by these Fresnel propagation effects, but only by the aperture geometry. This approach involves iterations between classical ray-tracing optical design optimization, and end-to-end Fresnel propagation with wavefront control (e.g. Electric Field Conjugation / Stroke Minimization). The construction of the testbed is planned to start in late Fall 2013.

Proc. of the SPIE 8864, 10 pages, 3 figures, Techniques and Instrumentation for Detection of Exoplanets VI

Cited by in corpus (9)

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• James Webb Space Telescope Optical Simulation Testbed I: Overview and First Results
• High-contrast imager for complex aperture telescopes (HiCAT): 5. first results with segmented-aperture coronagraph and wavefront control
• High-contrast imager for Complex Aperture Telescopes (HiCAT): 2. Design overview and first light results
• Experimental validation of active control of low-order aberrations with a Zernike sensor through a Lyot coronagraph
• Experimental validation of coronagraphic focal-plane wavefront sensing for future segmented space telescopes
• High-contrast Imager for Complex Aperture Telescopes (HiCAT): 6. Software Control Infrastructure and Calibration
• Estimating low-order aberrations through a Lyot coronagraph with a Zernike wavefront sensor for exoplanet imaging