Practical issues of feedback interferometry for adaptive optics

The idea of feedback interferometry for aberration correction was proposed by the author. Conventional adaptive optics (AO) systems usually use separate subsystems to perform wavefront sensing and correction, which involve large matrix manipulation. In a feedback interferometer, the intensity of the interference pattern is used to control the wavefront corrector, thus combining the two subsystems together. To develop a practical system for use in real turbulent environments, there are several issues that need to be considered. There are concerns in the control algorithm as well when try to use the system in practice. Scintillation and frequency response are the major issues. The frequency response determines how fast the aberration that the system can track and correct. Atmospheric induced aberration might have frequency components as high as 200 Hz.