title: Three-dimensional shape measurement of non-full-field reflective surfaces.
abstract: We describe a technique for the measurement of non-full-field reflective surfaces by using phase-stepping profilometry. We explain the principles of phase demodulation and discuss three-dimensional (3-D) height reconstruction in the case of measuring surfaces with reflective properties such as plain glass and mirrored glass. A number of required calibration algorithms are described to obtain surface slopes and reconstructed 3-D heights of the whole surface. Masking for non-full-field objects and the surface reconstruction procedure are demonstrated mathematically and algorithmically. Several experimental results are given for glass with different shapes and defects. Measurement of a spherical mirror with a known radius has also allowed us to show the performance of the proposed technique. This allows for the possibility to compare 3-D data from the known object with data taken from the measurement system.
authors.affiliation: General Engineering Research Institute, Liverpool John Moores University, James Parsons Building, Byrom Street, Liverpool L3 3AF, UK. oskydan@hotmail.com
authors.forename: Oleksandr A
authors.initials: OA
authors.lastname: Skydan
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Lalor
authors.forename: David R
authors.initials: DR
authors.lastname: Burton