Birefringence optical fibers (OF) appeared in 1978–1983 together with the technologies of thermoelastic inserts in the workpieces for drawing optical fibers. This article deals with two basic methods of measurement of embedded BOFs: spectral method and elastic twisting method. Three OFs types, drawn from the workpieces with embedded linear birefringence are taken as objects of study: HiBi or also PM- (polarization maintaining) fibers; fibers, drawn from the same workpieces, but with the rotation of the workpiece – ​spun-fiber; LoBi-fibers, which by the method are referred to as spun-fibers. The technique of measuring the beat length of the embedded BOFs is described in detail.
The paper analyzes two known methods for measuring the characteristics of an embedded birefringence of special optical fibers. The features of beat length measurement of the embedded birefringence for each method and different types of special fibers are shown. Advantages, disadvantages and limitations for each of the methods are pointed.


Разработка: студия Green Art