LINEARISATION OF SCANNED DATA

摘要

A system for obtaining a signature a scan area on the surface of an article comprises: a signature generator that generates the signature from scattered coherent radiation detected from a plurality of regions on the surface by using relative motion between the article and a scan head comprising a coherent radiation source and photodetectors to obtain a set of data points comprising a group of data points from each region; an imaging detector that captures a sequence of images of the surface during the relative motion; and a processor that calculates the instantaneous velocity of the relative motion; whereby the signature generator uses the instantaneous velocity to linearise the groups of data point within the set of data points before generating the signature of the article from the set of data points.