Fibre Optics in Metrology.

The article presents information on Fibre Optics in Metrology. Since the mid--1960s the idea of communication through optical fibres has developed into a vital branch of electro-optics. From the viewpoint of optical metrology, optical fibres are an attractive alternative for the guiding of light. An even more important reason for studying optical fibres is their potential for making new types of sensors. Another construction than the step-index (SI) fibre sketched is the so-called graded-index (GRIN) fibre. It has a core material whose refractive index varies with distance from the fibre axis. The light rays bend gradually and travel through a GRIN fibre in the oscillatory fashion.