The Effect Of Wavefront Sensor Characteristics And Spatiotemporal Coupling On The Correcting Capability Of A Deformable Mirror

By modeling a wavefront sensor and deformable mirror system as a high pass spatial and temporal frequency filter, its correcting ability in terms of a transfer function can be determined. Since the characteristics of a particular sensor/mirror system, as well as the uncorrected incident wavefront, affect the form of the transfer function, both must be used to describe the system's correcting ability. In this paper a mathematical formalism is presented that is based upon a linear systems approach and which relates the transfer function to the characteristics of a deformable mirror system. Three methods of introducing system characteristics into the filtering process to correct for random and deterministic errors are presented. In situations where spatiotemporal coupling becomes important, a three dimensional filter in frequency space is employed.