Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Robust Wrapping-free Phase Retrieval Method Based on Weighted
  Least-square Method   For many profilometry techniques, phase unwrapping is one of the most
challenging process. In order to sidestep the phase unwrapping process,
Perciante et. al [Appl Opt 2015; 54(10):3018-23] proposed a wrapping-free
method based on the direct integration of the spatial derivatives of the
patterns to retrieve the phase. But it is only applicable for the case of the
phase continuity for the tested object, which means it may fail to handle
fringe patterns containing complicated singularities, such as noise, shadow,
shears and surface discontinuity. In view of this problems, a robust
wrapping-free phase retrieval method is proposed in this paper, which is based
on combined Perciante's method and weighted least-squares method. Two partial
derivatives of the desired phase is obtained from the fringe patterns,
meanwhile the carrier is eliminated using direct phase difference method. The
phase singularities are determined using derivative variance correlation map
(DVCM), and the weighting coefficient is obtained from the binary mask of the
reverse DVCM. Simulations and experiments are conducted to prove the validity
of the proposed method. Results are analyzed and compared with those of
Perciante's method, demonstrating that the proposed method can be available for
measuring objects with some kinds of singularities sources.

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The categories of this paper are: math
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The categories of this paper are: bayes-an
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The categories of this paper are: cond-mat
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The categories of this paper are: solv-int
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The categories of this paper are: nlin
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The categories of this paper are: eess
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The categories of this paper are: quant-ph
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The categories of this paper are: dg-ga
31
The categories of this paper are: ao-sci
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The categories of this paper are: q-alg
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-th
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The categories of this paper are: funct-an
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The categories of this paper are: atom-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: patt-sol