In order to meet the wavefront processing requirements of liquid crystal adaptive optics system which match 4 m astronomy telescope
a wavefront processor (LCWP) based on multi-GPU is developed. First
the liquid crystal adaptive optics wavefront processing method is described. The numbers of hartmann detector's microlenses
Zernike modes and liquid crystal corrector's drive unit are analyzed
which need to match 4 m telescope. Then the wavefront processing methods based on multi-GPU are discussed in detail: single GPU method is used to calculate slope; block-column distribution method is used to fit Zernike coefficient; Zernike polynomial symmetry algorithm and block-row distribution method are used to compute gray map of liquid crystal corrector. Finally
the transfer function of liquid crystal adaptive optics system for matching 4 m telescope is analyzed and magnitude of the residual error transfer function is simulated. The latency of slope calculation is 18
s
the latency of Zernike coefficient fitting is 39
s and the latency of computing gray map is 114
s. The total computing latency is 109
s and temporal band width in our liquid crystal adaptive optics system is 53 Hz. It is shown that our LCWP based on multi-GPU has the ability to match 4 m astronomy telescope.
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references
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