Phase discrepancy induced from least squares wavefront reconstruction of wrapped phase measurements with high noise or large localized wavefront gradients

摘要

Adaptive optics is used in applications such as laser communication, remote sensing, and laser weapon systemsto estimate and correct for atmospheric distortions of propagated light in real-time. Within an adaptive opticssystem, a reconstruction process interprets the raw wavefront sensor measurements and calculates an estimatefor the unwrapped phase function to be sent through a control law and applied to a wavefront correctiondevice. This research is focused on adaptive optics using a self-referencing interferometer wavefront sensor,which directly measures the wrapped wavefront phase. Therefore, its measurements must be reconstructedfor use on a continuous facesheet deformable mirror. In testing and evaluating a novel class of branch-point-tolerant wavefront reconstructors based on the post-processing congruence operation technique, an increase inStrehl ratio compared to a traditional least squares reconstructor was noted even in non-scintillated fields.To investigate this further, this paper uses wave-optics simulations to eliminate many of the variables from ahardware adaptive optics system, so as to focus on the reconstruction techniques alone. The simulation resultsalong with a discussion of the physical reasoning for this phenomenon are provided. For any applications usinga self-referencing interferometer wavefront sensor with low signal levels or high localized wavefront gradients,understanding this phenomena is critical when applying a traditional least squares wavefront reconstructor.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.