تاثير نصف قطر الانحناء على قياس الانكسار الثنائي النمطي لليف البصري احادي النمط

The curvature of radius effect on modal birefringence for single- mode optical fiber has been stndeed and were taken outer radius (105 m) coiled on a former for different radii ranging (29 ,40,70 mm) to induced weakly birefringence in fiber with different turns number of optical fiber optic. Show The result has been obtained from research has showed that when the curvature of radius increased, the modal birefringence magnitude decreased. The relationship between the bend of length and the bending Birefringence was linear for the same radii .Also , the relationship between the reciprocal square of the bend radius and the bend of birefringence has been studied was linear for large bend radii and the slight deviation from linearity for the small bend radii.