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Sorting method to extend the dynamic range of the Shack-Hartmann wave-front sensor.

Junwon Lee·Roland V Shack·Michael R Descour
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Abstract

We propose a simple and powerful algorithm to extend the dynamic range of a Shack-Hartmann wave-front sensor. In a conventional Shack-Hartmann wave-front sensor the dynamic range is limited by the f-number of a lenslet, because the focal spot is required to remain in the area confined by the single lenslet. The sorting method proposed here eliminates such a limitation and extends the dynamic range by tagging each spot in a special sequence. Since the sorting method is a simple algorithm that does not change the measurement configuration, there is no requirement for extra hardware, multiple measurements, or complicated algorithms. We not only present the theory and a calculation example of the sorting method but also actually implement measurement of a highly aberrated wave front from nonrotational symmetric optics.

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AlgorithmsEquipment DesignEquipment Failure AnalysisImage EnhancementImage Interpretation, Computer-AssistedOphthalmoscopesOphthalmoscopyRefractometryTransducersEvaluation StudyJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, U.S. Gov't, P.H.S.

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Junwon Lee, Roland V Shack, Michael R Descour. 2005-08-10. Sorting method to extend the dynamic range of the Shack-Hartmann wave-front sensor.. https://doi.org/10.1364/ao.44.004838

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