In this work two-beam, multiple-beam and manual variable wavelength
(VAWI) interferometric techniques were applied to study the dispersion
properties and structural deformation of polymer fibres. These
techniques are used to measure the refractive indices, refractive index
profiles and birefringence for deformed and un-deformed fibres. The
fibre drawing devices attached with interference microscopes and systems
are used to investigate and detect various types of deformations
associated with stretched polymer fibres.