Atmospheric turbulence corrupts astronomical images formed by ground-based telescopes. Adaptive optics systems allow the effects of turbulence-induced aberrations to be reduced for a narrow field of view corresponding approximately to the isoplanatic angle
. For field angles larger than
, the point spread function (PSF) gradually degrades as the field angle increases.
We present a technique to estimate the PSF of an adaptive optics telescope as function of the field angle, and use this information in a space-varying image reconstruction technique. Simulated anisoplanatic intensity images of a star field are reconstructed by means of a block-processing method using the predicted local PSF. Two methods for image recovery are used:
matrix inversion with Tikhonov regularization, and the Lucy–Richardson algorithm. Image reconstruction results obtained using the space-varying predicted PSF are compared to space invariant deconvolution results obtained using the on-axis PSF. The anisoplanatic reconstruction technique using the predicted PSF provides a significant improvement of the mean squared error between the reconstructed image and the object compared to the deconvolution performed using the on-axis PSF.
© 2007 Optical Society of America
(010.1080) Atmospheric and oceanic optics : Active or adaptive optics
(100.3010) Image processing : Image reconstruction techniques
(110.6770) Imaging systems : Telescopes
Original Manuscript: April 2, 2007
Manuscript Accepted: June 13, 2007
Published: August 10, 2007
Mathieu Aubailly, Michael C. Roggemann, and Timothy J. Schulz, "Approach for reconstructing anisoplanatic adaptive optics images," Appl. Opt. 46, 6055-6063 (2007)