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International audience; In the domain of 3D measurement for inspection purposes, standard systems based on triangulation approaches, can be limited by the nature of the observed surface. When the surface is not lambertian, i.e. highly reflective or transparent, other strategies to ease the measurement need to be developed. The idea of using the polarization property of the light is one of them. This was explored to be a complementary modality, in triangulation or shape from distortion methods, or used in a standalone system through the concept of "shape from polarization". In this paper we propose a short state of the art of the usage of polarimetric imaging for the study of surface and the measurement of 3D data. We focus on recent development applied to the industrial domain, or the health domain.

Two measurement systems based on electronic imagers for attitude determination of light and low-cost airborne vectors in clear weather condition are presented. Both the devices are based on the following scheme: a binarized sky line image is selected as referential, then each shot, after binarization is segmented in two parts whose mean values are subtracted to the corresponding data computed from referential image. From this comparison analogical or digital values are deduced that give way to estimating the roll and pitch variation angles. The first system is made of off-the-shelf devices: black and white CMOS camera and processing unit made of a dedicated electronic. A second proposition is presented. It makes use of a CMOS retina, developed by our team, dedicated to real time, analogical intercorrelation computing. A simple external processing implemented in a microcontroller completes the system. A model for the embarked imaging system and an equation for an ideal horizon image with respect to rolling and pitch angles are proposed. The method for estimating these angles from the image and errors induced by the various approximations of the model are then presented. A series of experimental results obtained from real images confirms the previous propositions. The last section is dedicated to a presentation of the retinal imager solution, experimental results are also provided in this part.