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Chapter 9
Uncertainty in Phase
Measurements
Erwin Hack
Electronics/Metrology/Reliability Laboratory
EMPA-Materials Science and Technology
Dubendorf, Switzerland
9.1 INTRODUCTION
An electromagnetic signal is described by its amplitude, state of phase,
and state of polarization. Such signals are found in very dierent branches
of science, such as electronics, telecommunication, interferometry, ultra-
sound, and phase-contrast x-ray tomography. Although the amplitude of
the signal is easily accessible through the measurement of the intensity with
a power detector or camera, retrieving the phase from intensity measure-
ments (images) is more involv ...