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Editors contains: "Porras-Aguilar, Rosario"

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  1. ; ; ; ; ; (, Proceedings Volume 12223, Interferometry XXI; 1222304 (2022) https://doi.org/10.1117/12.2634327 Event: SPIE Optical Engineering + Applications, 2022, San Diego, California, United States)
    North-Morris, Michael B.; Creath, Katherine; Porras-Aguilar, Rosario (Ed.)
    A novel Vision ray metrology technique is reported that estimates the geometric wavefront of a measurement sample using the sample-induced deflection in the vision rays. Vision ray techniques are known in the vision community to provide image formation models even when conventional camera calibration techniques fail. This work extends the use of vision rays to the area of optical metrology. In contrast to phase measuring deflectometry, this work relies on differential measurements, and hence, the absolute position and orientation between target and camera do not need to be known. This optical configuration significantly reduces the complexity of the reconstruction algorithms. The proposed vision ray metrology system does not require mathematical optimization algorithms for calibration and reconstruction – the vision rays are obtained using a simple 3D fitting of a line. 
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  2. ; ; (, SPIE Optical Engineering + Applications, 2020, Online Only)
    North Morris, Michael B.; Creath, Katherine; Porras-Aguilar, Rosario (Ed.)
    This work presents a stable noise-robust numerical integration technique derived from a gradient representation of the Q-Forbes polynomials for surfaces with axial symmetry. This modal-integration technique uses an orthogonalization process through the Householder reflections to obtain a numerically orthogonal set for the surface slopes that is used to reconstruct the surface shape. It is shown that for typical Deflectometry measurements, the resulting random component of the uncertainty after numerical integration has a root mean square error well below 1nm. 
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