Adaptive Optics Correction of the Wavefront Distortions Induced by   Segments Misalignment in Extremely Large Telescope
  The capability of the adaptive optics to correct for the segmentation error is analyzed in terms of the residual wavefront RMS and the power spectral density of the phase. The analytical model and the end-to-end simulation give qualitatively equal results justifying the significance of the geometrical matching between segmentation geometry and the actuators/subaperture distribution of the adaptive optics. We also show that the design of the wavefront sensor is rather critical. 
Natalia Yaitskova and Christophe Verinaud