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Hier finden Sie wissenschaftliche Publikationen aus den FraunhoferInstituten. Efficient phaseunwrapping algorithm by using phase blocks
 Wen, T.d.: 3rd International Symposium on Test and Measurement, ISTM/99. Conference proceedings Beijing: International Academic Publishers, 1999 ISBN: 7800034410 S.630633 
 International Symposium on Test and Measurement (ISTM) <3, 1999, Xi'an> 

 Englisch 
 Konferenzbeitrag 
 Fraunhofer IPT () 
 phase unwrapping by blocks; cellular automata; pathdependant phase unwrapping 
Abstract
Phase unwrapping is extensively used in optical measurements where phaseshifting technique is employed. For removing 2 piphase jumps resulted from phase computation, pathdependent and pathindependent (cellular automata) algorithms for phaseunwrapping are usually employed. The method described in this paper is the phase unwrapping by blocks which combines the advantages of both the pathdependent and the cellular automata algorithms. It determines unwrapping strategy according to the fringe distributions of wrapped phase map, divides the phase map into phase blocks of different sizes and unwraps them by using either pathdependent or cellular automata algorithms. The unwrapped phase maps blocks are then connected into a complete phase map with one line or column of each neighboring block overlapped. A criterion for block divisions and for marking inconsistent data (bad points) is given. The proposed phaseunwrapping method is of high speed in unwrapping as compared with the conventional pathdependent and the path independent unwrapping rnethods. Computer memories can be saved by use of this method and the method is therefore especially suitable for unwrapping largesized phase maps.