Phase retrieval from one or more intensity measurements is a potentially powerful and appealing technique for real-time adaptive-optics wave-front sensors. Under the assumption of small wave-front phase excursions, one is able to derive an exact solution to the inverse problem given three or more intensity measurements with known phase offsets. Applications include a high-order wave-front sensor to correct for residual aberrations in an adaptive-optics system in tandem with a low-resolution Hartmann–Shack wave-front sensor. The formula can also furnish mathematical insights into the full nonlinear phase-retrieval task.
© 1998 Optical Society of America
Walter J. Wild, "Linear phase retrieval for wave-front sensing," Opt. Lett. 23, 573-575 (1998)