Paper
28 August 2014 Experimental study of a low-order wavefront sensor for high-contrast coronagraphic imagers: results in air and in vacuum
Author Affiliations +
Abstract
For the technology development of the mission EXCEDE (EXoplanetary Circumstellar Environments and Disk Explorer)—a 0.7 m telescope equipped with a Phase-Induced Amplitude Apodization Coronagraph (PIAA- C) and a 2000-element MEMS deformable mirror, capable of raw contrasts of 10−6 at 1.2 λ/D and 10−7 above 2 λ /D — we developed two test benches simulating its key components, one in air, the other in vacuum. To achieve this level of contrast, one of the main goals is to remove low-order aberrations, using a Low-Order WaveFront Sensor (LOWFS). We tested this key component, together with the coronagraph and the wavefront control, in air at NASA Ames Research Center and in vacuum at Lockheed Martin. The LOWFS, controlling tip/tilt modes in real time at 1 kHz, allowed us to reduce the disturbances in air to 10−3 λ/D rms, letting us achieve a contrast of 2.8×10−7 between 1.2 and 2 λ/D. Tests are currently being performed to achieve the same or a better level of correction in vacuum. With those results, and by comparing them to simulations, we are able to deduce its performances on different coronagraphs— different sizes of telescopes, inner working angles, contrasts, etc. — and therefore study its contribution beyond EXCEDE.
© (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Julien Lozi, Ruslan Belikov, Sandrine J. Thomas, Eugene Pluzhnik, Eduardo Bendek, Olivier Guyon, and Glenn Schneider "Experimental study of a low-order wavefront sensor for high-contrast coronagraphic imagers: results in air and in vacuum", Proc. SPIE 9143, Space Telescopes and Instrumentation 2014: Optical, Infrared, and Millimeter Wave, 914322 (28 August 2014); https://doi.org/10.1117/12.2056735
Lens.org Logo
CITATIONS
Cited by 5 scholarly publications.
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Cameras

Coronagraphy

Cooling systems

Temperature metrology

Wavefront sensors

Space telescopes

Sensors

Back to Top