Laser Sensor For Process Tomography Study

Process Tomography involves using tomography imaging method to manipulate data from remote sensor in order to obtain object field distribution information from inaccessible location. And the laser PT technique discussed here is a novel industrial process tomography based on a transilluminated mode, which employs the principles of light absorption and scattering together with image reconstruction from projection to reconstruct the spatial distribution data of measured object via measuring light data modulated by it on the background of medical CT. It, as a non-invasive, non-contact and non-contaminative measurement, shows great advantages in industrial application such as industrial process imaging, biological issues imaging, atmosphere pollution monitoring, material surface crack detecting and so on. At present, this technique becomes one of international hot research items.In this paper, the characteristics of many sensor arrays and the varied algorithms of image reconstruction are studied by means of simulating first, based on the basic principle of laser sense tomography. Next, the experiment researches are brought into execution through self-made experiment equipments, mainly including:1. Fundamental, present development situation, sixty-four-dollar questions and difficulties of Optical PT.2. Analysis of optical model, sensing principle of laser sensors and mathematics model of image reconstruction from projections.3. Several kinds of sensors array have been brought forward and designed. Characters, especially sensitivity characters of their optical sensitivity fields have been also discussed in detail.4. Simulation researches on several image reconstruction algorithms corresponded to sensors structures in MATLAB have been performed to analyze the reconstruction capability of these algorithms. The best algorithm in various desires and conditions are decided through the comparison among the algorithms.5. In experiment research, control of parallel and serial drive mode of laser sensors,multiplex A/D transform and dynamic image reconstruction, display and saving for replaying are realized with soft aiming at the key questions of laser PT. And reconstructed images and analysis results of system capability are successfully obtained. Furthermore, the identify on line of flow model and relationship of quality flux and light projections have been elementarily found through plenty of experiments on quartz particles flow fields. This approved laser PT is applicable to flow quantity measurement in two-phase flow of gas and solid.