Patent attributes
Described are a multiple channel interferometric surface contour measurement system and methods of determining surface contour data for the same. The measurement system includes a multiple channel interferometer projector, a digital camera and a processor. Fringe patterns generated by spatially separate channels in the projector are projected onto an object surface to be measured. The digital camera acquires images of the fringe patterns and the processor determines surface contour data from the fringe patterns. More specifically, fringe numbers are determined for points on the object surface based on image data. The fringe numbers are modified according to collinear adjustment values so that the modified fringe numbers correspond to a common, collinear axis for the interferometer projector. After unwrapping the modified fringe numbers, the unwrapped values are modified by the collinear adjustment values to obtain accurate fringe numbers for the pixels in each interferometer channel.
