Under CopyrightWerling, S.S.WerlingBalzer, J.J.BalzerBeyerer, J.J.Beyerer2022-03-101.9.20152007https://publica.fraunhofer.de/handle/publica/35469610.24406/publica-fhg-354696This contribution focusses on the regularization of the ill-posed deflectometry problem, in which the reconstruction of a specular object from the modulation of the reflected scene is desired. In the case where a single surface point is known, existence and uniqueness of solution can be proven considering the underlying system of quasilinear partial differential equations. Otherwise, additional information has to be utilized to resolve the ambiguity. Two examplary methods are presented under review and experimental assessment, namely specular stereo and the Shape-from-Shading approach for partially specular surfaces.en004conference paper