Patent ID: 7428056

Claim:
A method for analyzing a surface of a test object, the method comprising: using an interferometry system comprising a broadband light beam to scan the surface of the test object and to thereby generate an interferometry signal comprising a time domain signal; wherein using the interferometry system to scan the surface of the test object comprises vertically scanning a position on the surface of the test object and generating the interferometry signal and the time domain signal at selected unique times during the vertical scanning; applying multiple windows to the interferometry signal to obtain a windowed interferometry signal; dividing the time domain signal into a plurality of time-differentiated segments; dividing the frequency domain signal into a plurality of time differentiated segments corresponding to the plurality of time differentiated segments of the time domain signal; and characterizing the surface of the test object using the windowed interferometry signal, wherein characterizing the surface of the test object comprises using the plurality of time differentiated segments of the frequency domain signal and the plurality of time differentiated segments of the time domain signal to characterize the surface of the test object.