par Delplancke, Françoise 
Référence Proceedings of SPIE - The International Society for Optical Engineering, 3121, page (454-464)
Publication Publié, 1997
Référence Proceedings of SPIE - The International Society for Optical Engineering, 3121, page (454-464)
Publication Publié, 1997
Article révisé par les pairs
| Résumé : | The characteristics and performances of a new Mueller-matrix scatterometer will be described. Applications and results on industrial samples will be presented. The device measures the angular distribution of the 16 Mueller-matrix elements, characterizing completely the light polarization modifications induced by any sample, transparent or scattering, in reflexion or in transmission. The measurement is made in less than 1 s., with an accuracy higher than 95 %, for any angle of incidence and any scattering angle in the range of 0° (forward scattering) to 175° (near backscattering). The instrument is using electro-optical polarization modulation techniques for polarization generation, a 4-detector photo-polarimeter for polarization detection, and Fast Fourier Transform (FFT) for the analyzis of the 4 signals. The interest of Mueller-matrix analyzis is that, compared to simple scatterometric measurements, this method can give information about the non-ideality of the analyzed samples: shape of the particles in suspensions, multiple reflexions, presence of contaminants, roughness shape of surfaces, porosity, presence of thin surface films. This information is very valuable for complex industrial samples. The applicxations include testing of transparent, non-scattering elements (liquid crystal devices), characterization of scattering translucent samples (suspensions in chemical industries), and inspection of rough surfaces covered or not by thin films (e.g. steel or aluminum sheets on production lines, electrochemical deposits). A future developement of the methjod for imaging Mueller-matrix polarimetry-scatterometry will also be described. |
