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Chapter 4
The Spiral Phase Transform
Kieran G. Larkin
Nontrivialzeros Research
Sydney, Australia
4.1 INTRODUCTION
e spiral phase transform (SPT) is one of the simplest algorithms for
demodulation of two-dimensional (2-D) fringe patterns. In its most com-
pact form, the transform requires only two multiplication operations
(one in the spatial domain, one in the Fourier domain) and one addition.
Essential theory and practical details for implementation are presented.
4.2 THEORY
4.2.1 Demodulation in One and Two Dimensions
Given the two-dimensional (2-D) image represented by the following
equation, an intensity fringe pattern (viz. interferog ...