Patent Document ID: 8463077
Application ID: 13430309
Patent Status: 1

Claim One:
1. A method for generating an unwrapped phase map, wherein the method comprises: generating interferograms of an object image; generating a wrapped phase map of the object image from the interferograms by application of a phase-shift algorithm; detecting phase jumps and noise in the wrapped phase map; considering a first phase jump position, a second phase jump position, a third phase jump position and a fourth phase jump position, all corresponding to one of a column (or a row) of the wrapped phase map; classifying a first phase value of a first phase comprising phase values, the noise and holes at the left of the second phase jump position, and classifying a second phase value of a second phase comprising phase values, the noise and holes between the third phase jump position and the fourth phase jump position; calculating a first row center from the first phase and a second row center from the second phase; interpolating a first phase center of the first row center position based on the first row center position and neighboring integral row pixels thereof; interpolating a second phase center of the second row center position based on the second row center position and neighboring integral row pixels thereof; generating a third phase by performing a first relative rotation of the first phase around the first phase center by a first angle so as to preserve the phase values, the noise and holes of the first phase, and generating a fourth phase by performing the first relative rotation of the second phase around the second phase center by a second angle to preserve the phase values, the noise and holes of the second phase; generating a fifth phase by performing a second relative rotation of the third phase around the first phase center by a third angle without changing a position of the fourth phase; generating a resultant phase by shifting the fifth phase and performing a stitching process in which a sixth phase is generated by stitching the resultant phase and the fourth phase; wherein the sixth phase is free from phase jumps between the first phase jump position and the fourth phase jump position; repeating cycles of the first relative rotation, the second relative rotation and the stitching process to obtain a seventh phase corresponding to one of a column (or a row) of the two-dimensional phase map obtained from application of the cycles; wherein the sixth phase of present said cycle is said first phase of next said cycle; wherein the seventh phase is free from phase jumps corresponding to the column (or the row) of the two-dimensional phase map; generating a first three-dimensional unwrapped phase map by performing a first absolute rotation of the seventh phases corresponding to all columns (or rows) of the two-dimensional phase map; and generating a second three-dimensional unwrapped phase map by performing a second absolute rotation of phases obtained corresponding to the seventh phases after application of the first absolute rotation; wherein the second three-dimensional unwrapped phase map has a prescribed phase distribution and is free from noise error, shifting error and hole error, wherein the second three-dimensional unwrapped phase map having a prescribed phase distribution that can be inspected at a human vision scale.