Method and arrangement for tracking movement relative to a surface

摘要

In an embodiment, a method of tracking movement relative to a surface involves comparing at least some data elements of a first array with at least some of data elements of a second array if it is determined, from an examination of the first array of data elements, that a characteristic condition does not exist in the first array of data elements, wherein the characteristic condition is related to the uniformity of at least a majority of the data elements of the first array.