FIBER DRAWING TENSION MEASURING METHOD OF OPTICAL FIBER AND ITS DEVICE AND FIBER DRAWING TENSION CONTROL DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a fiber drawing tension measuring method and a device and a tension control device capable of heightening control reliability of an automatic control operation and guaranteeing stable production of a highest- quality optical fiber, by enabling accurate detection of a natural frequency peak value and by enabling accurate drawing out by using a tension having a calculated optimum drawing condition different in each base material. ;SOLUTION: In this fiber drawing tension measuring method of an optical fiber for measuring a vibration waveform of the optical fiber which is just being drawn by a vibration measuring means and for obtaining the tension of the optical fiber from a natural frequency peak of the vibration waveform, the vibration waveform of the optical fiber 3 which is just being drawn is measured by the noncontact-type vibration measuring means 11, and frequency analysis of the vibration waveform is executed by using a maximum entropy method, and a distinguished peak frequency is taken as the natural frequency peak.;COPYRIGHT: (C)2001,JPO