METHOD OF MAKING BIREFRINGENT MICROSTRUCTURED OPTICAL FIBRE Russian patent published in 2011 - IPC G02B6/02 

FIELD: physics.

SUBSTANCE: according to the method, at least 4 grooves which are pairwise symmetric about a plane which passes through the longitudinal axis of rotation of the workpiece rod are obtained on the entire length of the workpiece rod. The structure of a fibre core, dimensions of which are determined by dimensions of an inscribed elllipse, is obtained in the cross-section. The workpiece rod and a quartz tube are fused in a non-working region and drawn into a pre-workpiece. The pre-workpiece is cut into pieces in which inner channels are etched. The inner and outer surfaces are washed and dried and then welded up on both ends. The pieces of the pre-workpieces are collected with a capillary quartz tube having a welded tubular holder. Pieces of the pre-workpiece and the capillary tube are fused on the side opposite the tubular holder. A preform is obtained as a result, which is drawn into an optical fibre coated with a protective reinforcing coating.

EFFECT: obtaining optical fibre with high birefringence and wide range of geometric shapes of the core of the optical fibre.