Patent attributes
Interferometric methods and apparatus by which the map between pixel positions and corresponding part locations are determined in situ. The part under test, which is assumed to be a rigid body, is precisely moved from a base position to at least one other position in one to six degrees of freedom in three-dimensional space. Then, the actual displacements are obtained. The base position is defined as the position with the smallest fringe density. Measurements for the base and all subsequent positions are stored. After having collected at least one measurement for each degree of freedom under consideration, the part coordinates are calculated using the differences of the various phase maps with respect to the base position. The part coordinates are then correlated with the pixel coordinates and stored.
