Patent ID: 7041334

Claim:
An optical fiber drawing method for drawing an optical fiber using an optical fiber drawing apparatus, the optical fiber drawing apparatus comprising a first resin coating apparatus and a second resin coating apparatus, the first resin coating apparatus comprising a first optical fiber drawing die and a coating cup, the second resin coating apparatus comprising a second optical fiber drawing die, the method comprising the steps of: calculating an interfacial shear rate for a drawing speed of at least 20 m/sec in accordance with a pressure value of resin inside the coating cup; forming a resin-coated optical fiber, the act of forming comprising applying a resin coat to the optical fiber using the first resin coating apparatus at the interfacial shear rate and at the drawing speed of at least 20 m/sec, wherein the interfacial shear rate of the optical fiber to the resin is within a range of −1.5×10 5 to 0 sec −1 ; calculating a second interfacial shear rate of the resin-coated optical fiber to the resin in accordance with a diameter of the resin coat; and applying a second resin coat to the resin-coated optical fiber using the second resin coating apparatus at the second interfacial shear rate and at the drawing speed of at least 20 m/sec, wherein the second interfacial shear rate is within a range of −3×10 5 to 2×10 5 sec −1 .