title: Simultaneous acquisition of 3D shape and deformation by combination of interferometric and correlation-based laser speckle metrology.
abstract: A metrology system combining three laser speckle measurement techniques for simultaneous determination of 3D shape and micro- and macroscopic deformations is presented. While microscopic deformations are determined by a combination of Digital Holographic Interferometry (DHI) and Digital Speckle Photography (DSP), macroscopic 3D shape, position and deformation are retrieved by photogrammetry based on digital image correlation of a projected laser speckle pattern. The photogrammetrically obtained data extend the measurement range of the DHI-DSP system and also increase the accuracy of the calculation of the sensitivity vector. Furthermore, a precise assignment of microscopic displacements to the object's macroscopic shape for enhanced visualization is achieved. The approach allows for fast measurements with a simple setup. Key parameters of the system are optimized, and its precision and measurement range are demonstrated. As application examples, the deformation of a mandible model and the shrinkage of dental impression material are measured.
authors.affiliation: Department of Prosthetic Dentistry and Biomaterials, University of Münster, Waldeyerstraße 30, 48149 Münster, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Dekiff
authors.affiliation: Department of Prosthetic Dentistry and Biomaterials, University of Münster, Waldeyerstraße 30, 48149 Münster, Germany.
authors.forename: Philipp
authors.initials: P
authors.lastname: Berssenbrügge
authors.affiliation: Biomedical Technology Center of the Medical Faculty, University of Münster, Mendelstraße 17, 48129 Münster, Germany.
authors.forename: Björn
authors.initials: B
authors.lastname: Kemper
authors.affiliation: Institute of Applied Physics, University of Münster, Corrensstraße 2, 48149 Münster, Germany.
authors.forename: Cornelia
authors.initials: C
authors.lastname: Denz
authors.affiliation: Department of Prosthetic Dentistry and Biomaterials, University of Münster, Waldeyerstraße 30, 48149 Münster, Germany.
authors.forename: Dieter
authors.initials: D
authors.lastname: Dirksen
keywords: (030.6140) Speckle; (100.0100) Image processing; (120.0120) Instrumentation, measurement, and metrology; (120.2880) Holographic interferometry; (120.4290) Nondestructive testing; (150.0150) Machine vision