Spatially filtered wave-front sensor for high-order adaptive optics
- 1 May 2004
- journal article
- Published by Optica Publishing Group in Journal of the Optical Society of America A
- Vol. 21 (5), 810-819
- https://doi.org/10.1364/josaa.21.000810
Abstract
Adaptive optics (AO) systems take sampled measurements of the wave-front phase. Because in the general case the spatial-frequency content of the phase aberration is not band limited, aliasing will occur. This aliasing will cause increased residual error and increased scattered light in the point-spread function (PSF). The spatially filtered wave-front sensor (SFWFS) mitigates this phenomenon by using a field stop at a focal plane before the wave-front sensor. This stop acts as a low-pass filter on the phase, significantly reducing the high-spatial-frequency content phase seen by the wave-front sensor at moderate to high Strehl ratios. We study the properties and performance of the SFWFS for open- and closed-loop correction of atmospheric turbulence, segmented-primary-mirror errors, and sensing with broadband light. In closed loop the filter reduces high-spatial-frequency phase power by a factor of to In a full AO-system simulation, this translates to a reduction by up to 625 times in the residual error power due to aliasing over a specific spatial frequency range. The final PSF (generated with apodization of the pupil) has up to a 100 times reduction in intensity out to
Keywords
This publication has 6 references indexed in Scilit:
- The Structure of High Strehl Ratio Point‐Spread FunctionsThe Astrophysical Journal, 2003
- Experimental validation of Fourier-transform wave-front reconstruction at the Palomar ObservatoryOptics Letters, 2003
- Speckle Decorrelation and Dynamic Range in Speckle Noise–limited ImagingThe Astrophysical Journal, 2002
- Ground‐based Coronagraphy with High‐Order Adaptive OpticsThe Astrophysical Journal, 2001
- Phasing the mirror segments of the Keck telescopes II: the narrow-band phasing algorithmApplied Optics, 2000
- Characteristics of Phase-Aberrated Nondiffraction-Limited Laser BeamsApplied Optics, 1974