Abstract

Adaptive Optics (AO) has the capability of providing diffraction-limited images from ground-based astronomical telescopes through the turbulent atmosphere. Because of limitations in the AO system, the point spread functions (PSF’s) of the AO system suffers from incomplete compensation and variability. Depending on the observation wavelength (λ), the spatial coherence length of the atmosphere (r₀), the sub-aperture size (d), the correlation time of the atmosphere (τ₀), the sample time of the wavefront sensing (t_s), and the signal strength of the source, the Strehl ratios of the compensated images can vary considerably (between 2% – 90%). In addition, residual errors in tilt compensation due to the source signal strength can further degrade the image quality. Thus, AO compensated imaging genearally requires some post-processing to extract the maximum possible information. As long as the PSF for the imaging process is stationary, then standard deconvolution algorithms can be applied. These algorithms have been recently developed and applied to Hubble Space Telescope imaging and include maximum-likelihood, maximum-entropy and pixon-based algorithms, etc.[1].

© 1996 Optical Society of America