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Department of Engineering, ICT and Technologies for Energy and Transport Patent Title Procedure and system for the three-dimensional reconstruction of formations dispersed in a matrix material, in particular inclusions in crystalline matrices. Ref. CNR 10177 Assignee(s): CNR CNR Institute: IMEM Main Inventor: Andrea Zappettini Countries: IT Priority date: 05/09/2012 Abstract It is highly desirable to characterize the presence of inclusions in the matrix CdTe / CdZnTe, because these are detrimental to X-ray detector applications. The standard methods for the detection of inclusions do not allow a 3D reconstruction of the position of the inclusions in the crystalline matrix. For this reason, a technique was developed for the analysis of images collected by an optical microscope which allows to 1) identify the inclusions 2) count the inclusion number in the whole volume of the sample 3) determine the inclusion size 4) determine the inclusion disribution in 3D. The technique can be implemented on any existing optical microscope, allow using with standard personal computers for data processing, and exploiting open source software. The technique can also be used for surface reconstruction imaging and surface roughness measurements. Background Nowadays the commercial microscopy systems allow counting inclusions in a transparent matrix using the technique so called “extended focus”. However, this technique does not allow to determine the in depth position of the inclusions and therefore gives no information on the actual distribution of these in 3D. In addition, the count is an underestimate, because in the case of stacked inclusions, only the first one is counted. Technology The system was developed on a standard optical microscope in transmission. So any optical microscope in transmission can be adapted for the purpose. The system was equipped with a video camera and a silicon acquisition PC. The heart of the invention is an analytical procedure that allows the PC to process the image collected with extreme rapidity. Advantages and Applications The advantages of a fully 3D reconstruction of the distribution of inclusions in a matrix are obvious, such as the ability to grasp the existence of ordered structures (see figure). The system works perfectly in the case of tellurium inclusions in crystals of CdTe / CdZnTe, but it works in any case of any opaque inclusions in any transparent matrix. It can also be used to study surface morphology and determine surface roughness. Development stage A fully functional prototype of the invention is in use in IMEM-CNR laboratories. The systems automatically 2 scans samples 10x10 cm large and with thickness up to 3 cm. We are currently developing procedures for faster analysis or for the study of surfaces and in particular for the analysis of surface roughness. 47