| 摘要 |
PURPOSE:To constantly obtain an optical fiber having uniform diameter by providing a temp. controller for a base material and a tension controller for the drawn glass fiber to the title device for drawing a fluoride optical fiber base material. CONSTITUTION:The optical fiber glass base material 1 consisting essentially of a fluoride such as ZrF4 is heated by a heater 5, melted, and drawn into an optical fiber 2 by a capstan 4. In this case, the temp. of the heater 5 is detected by a thermocouple 6, the detected value is inputted to the temp. controller 10 to control the power supplied to the heater 5 from a heater power source 7 through a switch 9, and the temp. of the heater 5 is kept constant. When the drawing of the glass base material 1 is started under such conditions, the switch 9 is connected to the tension controller 11 for the optical fiber 2 and the power source 7. When the diameter of the optical fiber 2 becomes higher than a specified value, the tension is detected by the displacement of a dancer pulley 3, the power source 7 for the heater 5 is controlled by the tension controller 11 to reduce the tension of the optical fiber 2 with a load cell 8 provided to the lever 3b of the pulley 3, hence the temp. of the heater 5 is increased, and the diameter of the optical fiber 2 is reduced to the specified value. |
