Novel branch cuts’placement based on the outline of the modulation in phase unwrapping

In order to retrieve the nature phase of the tested objects in optical three dimensional sensing based on phase measuring profilometry,a new phase unwrapping method,which connects the residue pairs by branch cuts based on the outline of modulation of the measured object,was presented.The new algorithm employs Laplacian edge detection to extract the outline of modulation,used to guide the branch cuts setting.Then,adopting diamond phase-unwrapping algorithm,the wrapped phase of the measured object can be retrieved accurately.The experimental results show that this new method,combining with the advantages of the reliability of modulation and the rapidity of branch cut algorithm,can effectively remain the accuracy of the measurement and fast retrieve the nature phase of the tested objects under the condition of a steep-shape.It is three times faster than the reliabilityguided phase unwrapping algorithm.