Focal plane wavefront sensing on SUBARU/SCExAO

Focal plane wavefront sensing is an elegant solution for wavefront sensing since near-focal images of any source taken by a detector show distortions in the presence of aberrations. Non-Common Path Aberrations and the Low Wind Effect both have the ability to limit the achievable contrast of the finest coronagraphs coupled with the best extreme adaptive optics systems. To correct for these aberrations, the Subaru Coronagraphic Extreme Adaptive Optics instrument hosts many focal plane wavefront sensors using detectors as close to the science detector as possible. We present seven of them and compare their implementation and efficiency on SCExAO. This work will be critical for wavefront sensing on next generation of extremely large telescopes that might present similar limitations

Comparative theoretical and experimental study of a Shack-Hartmann and a Phase Diversity SENSOR, for high-precision wavefront sensing dedicated to Space Active Optics

International audienceThe RASCASSE project was commissioned by the french spatial agency (CNES) to study a critical element of the next-generation of Earth-imaging satellites: the wavefront sensor, which is a key subsystem of active optics. The project involved ONERA and Thales Alenia Space (TAS) to study the analyzers, and LAM to design and implement the experiment.At ONERA, we first performed end-to-end simulations of a Shack-Hartmann and a Phase Diversity wavefront sensor on both a point source and extended scenes, with realistic wavefronts supplied by TAS. Then we studied the sensitivity of the sensors and the optimization of their design as a function of several parameters, such as: the strength and the type of aberrations, the image subsampling, the aperture shape, the signal-to-noise ratio, the spectral bandwidth, the type of scene, etc..Finally, we performed experimental measurements on the bench at lam, where both analyzers were run concurrently. The precision we achieved was better than 1 nm rms per measured Zernike mode, for both types of analyzers

Experimental assessment of various optical communication chains for high-capacity optical feeder links

Optical feeder links (OFL) are expected to become part of future Very High Throughput Satellite (VHTS) systems in response to the growing demand for higher capacity and lower costs. H2020 VERTIGO (Very High Throughput Satellite Ground Optical Link) project was set to prove key optical communication technologies and to address: 1) Throughput increase with high spectral and power efficiencies. 2) Higher optical power generation and delivery. 3) Atmospheric turbulence mitigation by optical and digital processing

Focal Plane Wavefront Sensing on SUBARU/SCExAO

Focal plane wavefront sensing is an elegant solution for wavefront sensing since near-focal images of any source taken by a detector show distortions in the presence of aberrations. Non-Common Path Aberrations and the Low Wind Effect both have the ability to limit the achievable contrast of the finest coronagraphs coupled with the best extreme adaptive optics systems. To correct for these aberrations, the Subaru Coronagraphic Extreme Adaptive Optics instrument hosts many focal plane wavefront sensors using detectors as close to the science detector as possible. We present seven of them and compare their implementation and efficiency on SCExAO. This work will be critical for wavefront sensing on next generation of extremely large telescopes that might present similar limitations.Comment: SPIE proceeding : Astronomical Telescopes + Instrumentation 2020. arXiv admin note: text overlap with arXiv:1912.1017

Focal plane wavefront sensing on SUBARU/SCExAO

Focal plane wavefront sensing is an elegant solution for wavefront sensing since near-focal images of any source taken by a detector show distortions in the presence of aberrations. Non-Common Path Aberrations and the Low Wind Effect both have the ability to limit the achievable contrast of the finest coronagraphs coupled with the best extreme adaptive optics systems. To correct for these aberrations, the Subaru Coronagraphic Extreme Adaptive Optics instrument hosts many focal plane wavefront sensors using detectors as close to the science detector as possible. We present seven of them and compare their implementation and efficiency on SCExAO. This work will be critical for wavefront sensing on next generation of extremely large telescopes that might present similar limitations. © 2020 SPIE.This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]