0000000000660576
AUTHOR
Mathias Ferraton
Optimization of a polarization imaging system for 3D measurements of transparent objects
This paper presents a multispectral imaging system for 3D reconstruction of transparent objects based on "shape from polarization" technique. The originality of this work relies on a multispectral active lighting system which enables to cope with the two ambiguities on the zenith angle and azimuth angle. A calibration step allows optimising the polarimetric measurements. Example of a reconstructed transparent object is presented.
Surface Reconstruction of Transparent Objects by Polarization Imaging
This paper focuses a method to acquire the surface of transparent objects for 3D measurement. The technique relies on the so called ?Shape from Polarization? technique. The principle of this polarization imaging technique is as follows: after being reflected, an unpolarized light becomes partially linearly polarized. The surface normals can be evaluated by analyzing their polarization parameters and by knowing the refractive index of the object to be controlled. Finally, the 3D shape is obtained by integrating the normals field. After an introduction to expose the problematic, section 2 exposes the principles of polarization technique. The third and the last section deal with the polarimetr…
Active Lighting Applied to Shape from Polarization
We present a new way of solving the ambiguity that appears in the shape from polarization method. This ambiguity, concerning the normals orientation of the surface, was previously solved thanks to a propagation algorithm. In this paper, the ambiguity is solved thanks to a special active lighting. This method is less time computing and is more robust to noise acquisition. We first demonstrate how to compute the right normals on the whole surface. Then, we show an application on the 3D reconstruction of a specular metallic object made by stamping and polishing.
Shape from polarization: a method for solving zenithal angle ambiguity
International audience; We report a multispectral based method that permits the evolution of shape from polarization setup applied to 3D shape estimation of transparent objects. The setup is based on a polarization imaging technique which is a recent imaging method based on the analysis of the polarization state of the light in the observed scene. The technique has rapidly evolved with the development of electro-optic components and some polarization cameras are now available on the market. Shape from polarization consists in measuring the azimuthal and zenithal angles characterizing the normal of each point of the observed surface. We focus on the ambiguity in the measurement of the zenith…