From Event: SPIE Optical Engineering + Applications, 2016
An extension to zonal wavefront reconstruction estimation algorithms is proposed for irregular and discontinuous apertures. Many applications in astronomy and directed energy feature wavefront reconstruction over apertures partially obscured by a secondary mirror and its supports. In the worst case, these obscurations can separate the aperture into multiple discontinuous regions. The method proposed uses integration equations derived from the Taylor theorem assuming missing slope data. These integration equations are included in the least-squares solution of the wavefront and provide constants of slope integration which minimize the error introduced by the discontinuities. The equations can be included in any zonal estimation scheme. Several algorithms with and without the additional integration equations are evaluated against wavefronts gathered in recent optical flight tests. Finally, an evaluation of the noise-induced error is given for the same set of algorithms.
Joel Lau and Donald J. Wittich, "Wavefront reconstruction over discontinuous apertures by inclusion of additional integration equations," Proc. SPIE 9982, Unconventional Imaging and Wavefront Sensing XII, 99820B (Presented at SPIE Optical Engineering + Applications: August 31, 2016; Published: 19 January 2017); https://doi.org/10.1117/12.2238069.
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