Vol. 8, issue 03, article # 3
pdf Sanchez L. J., Leonardo J., Petrov R. G. About the optimization of partially correcting adaptive optics. // Atmospheric and oceanic optics. 1995. V. 8. No. 03. P. 347-355.Copy the reference to clipboard
Abstract:
At visible wavelengths, the long exposure point spread function (PSF) of large telescopes or interferometers can be only partially corrected by adaptive optics (AO). For system designed to compensate at infrared wavelengths, the element size or actuator spacing rЕ is equal to about 5 times the Fried parameter r0 in the visible. This is largely outside the range for which the normally used least–squares fits are optimum. Here we present some one dimension numerical experiments confirming that in the case of partially correcting AO, there exists an optimal compensation (here obtained by simulated annealing) that maximizes the Strehl ratio. To evaluate the effects of the atmospheric wave front temporal evolution on the corrected image quality, we calculated the resultant corrected long exposure PSF shape, as a function of the time delay existing between the wave front used for the computation of the correction and the wave front to which the correction is applied. In order to obtain a significant gain using the simulated annealing technique, this optimized correction must be applied within a delay smaller than half the speckle lifetime τ0.