تأثير طول الليف على قياس الانكسار الثنائي النمطي داخل الليف البصري أحادي النمط

Abstract

In this research the intrinsic modal birefringence has been measured for single- mode optical fiber without any extrinsic effect .It was taken a single- mode optical fiber ,the diameter of core material was (5µm) and the total diameter was (210µm) for different lengths of this fiber. Show the result has been obtained from research which the magnitude of model birefringence of this fiber (B=5.74×10-7 deg.m-1), beat length (Lb=1.09m) and the value of the difference in the propagation constants between the two axis the fast and the slow (Δ β=328 deg.m-1).