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Chapter 2
Windowed Fourier
Transforms
Jingang Zhong
Department of Optoelectronic Engineering
Jinan University
Guangzhou, China
Jiawen Weng
College of Science
South China Agricultural University
Guangzhou, China
2.1 INTRODUCTION
Phase demodulation techniques, as automatic analysis techniques for
fringe signals in optical metrology, have been widely used for applica-
tions such as three-dimensional (3-D) shape measurement [1,2], vibra-
tion analysis [3], and strain analysis [4]. Fourier transform (FT) methods
[2] and phase-shiing methods [5,6] are typical techniques for phase
demodulation. In practice, the fringe signals may be nonsinusoidal sig-
na