Measuring high phase differences in samples

摘要

A process and installation are for an automatic and contact-free measurement of high phase differences of birefractive and transparent samples (3) on the basis of senarmont fibres, filaments, films and surface structures in particular. The materials can show false colours in white light. The process involves determining the equatorial intensity distributions for at least two characteristic wave lengths simultaneously. On the basis of this determination, the senarmont angle and the phase differences are announced simultaneously. Subsequently, the absolute difference of the phase differences between each two adjacent wave lengths is determined across a range of several arrays. The absolute minimum of the absolute difference for each wave length pair is indicated, together the right array and subsequently the phase difference for each characteristic wave length.