Shape from polarization in the far IR applied to 3D digitization of transparent objects

This paper presents an application of ``shape from polarization'' method in the far Infrared range with applications for three-dimensional reconstruction of transparent objects. Shape from polarization is a recent application of more general polarization imaging technique having the aim to digitize the shape of the observed object. The principle is to evaluate the normal on each observed point followed by an integration procedure. The technique is well developed in the visible domain, but not in the far infrared domain due to the requirement of telecentric optics. We propose here a complete setup in the 8-13 micrometer spectral band with an appropriate source and a reconstruction method including the pinhole camera model in order to use standard optics for the camera. We present primary results of threedimensional digitization of transparent objects.