| 摘要 |
PURPOSE: To suppress the fluctuation in a wire diameter in a longitudinal direction by subjecting a plastic optical fiber perform to a pretreatment to heat this perform to a prescribed temp. prior to a drawing stage, then melting the perform by heating and drawing the perform. CONSTITUTION: A drawing device 10a for the plastic optical fiber is composed of a drawing furnace 12, an outside diameter monitor 14 and a winding means 16. This method includes a step for the pretreatment to heat the plastic optical fiber perform 26 including a core part and a clad part having the refractive index lower than the refractive index of the central part of the core to a prescribed temp. and a step for drawing to draw the plastic optical fiber perform by heating and melting. This prescribed temp. is >=100 deg.C. The unreacted monomer-component slightly remaining in the perform is evaporated and is completely removed from the perform by heating the perform in such a manner. Then, the drawing is executable without deforming a neck-down part even if the perform is heated to >=200 deg.C for the purpose of heating and melting. |
