LINEAR-PHASE RETRIEVAL FOR WAVE-FRONT SENSING

Phase retrieval from one or more intensity measurements is a potential ly powerful and appealing technique for real-time adaptive-optics wave -front sensors. Under the assumption of small wave-front phase excursi ons, one is able to derive an exact solution to the inverse problem gi ven three or more intensity measurements with known phase offsets. App lications include a high-order wave-front sensor to correct for residu al aberrations in an adaptive-optics system in tandem with a low-resol ution Hartmann-Shack wave-front sensor. The formula can also furnish m athematical insights into the full nonlinear phase-retrieval task. (C) 1998 Optical Society of America.