There has long been interest in reducing or circumventing the limitations imposed by atmospheric turbulence on optical imaging systems. Recent studies have shown that irradiance or speckle interferometry, or real-time atmospheric compensation, may be used to regain diffraction-limited performance. In this paper, the relationship between real-time phase compensation and the optimum channel-matched filter compensator is developed, with emphasis on the fundamental limits imposed by the propagation medium. In particular, the effects of uncompensated amplitude fluctuations and finite isoplanatic diameter are evaluated. It is shown that the former does not usually present any limitation on imaging performance, whereas the latter may severely limit the field of view over which diffraction-limited imaging can be realized. Results are presented for both coherently and incoherently illuminated objects.
© 1976 Optical Society of AmericaPDF Article