A decoupling control algorithm for Woofer-Tweeter adaptive optics system in generalized irregular pupil region
We proposed a decoupling control algorithm to accomplish the application of woofer-tweeter (W-T) adaptive optics system in generalized irregular pupil region. This algorithm firstly modifies the response matrix of woofer and tweeter by setting corresponding value at some sub-apertures of Shack-Hartmann(S-H) sensor to zero and constructs a slope-based orthogonal basis used to distribute different spatial frequency aberration to dual deformable mirrors (DMs). Then a limited condition is used to calculate the pseudo-inverse matrix of modified response matrix of dual DMs through single value decomposition. Finally, to restrain tweeter generating cross-coupling shape with woofer, a constraint matrix used to reset control vector of tweeter is constructed with the slope-based orthogonal basis and modified response matrix of tweeter. Numeral simulation of W-T adaptive optics system is built to verify the performance of this algorithm and results demonstrate that this algorithm has a good performance to control the W-T adaptive optics system in generalized irregular pupil region, and achieve better performance to suppress the cross-coupling between woofer and tweeter than Zernike decomposition algorithm. At the same time, the experimental results for the W-T AO system demonstrated that this algorithm is practical for the AO system with dual DMs in generalized irregular pupil region.