METHOD AND APPARATUS FOR PRODUCING OPTICAL FIBER PREFORM

摘要

A method and a device (100) for fabricating a single mode fiber preform (20) can reduce time for completing the collapsing of the barrier tube (28) by applying vacuum (206) to an annular gap formed between the barrier tube (28) and the core (22) during heating, and can enhance the optical properties by introducing a gas or a mixture of gases (108) into the annular gap prior to the vacuum application. The apparatus comprises a glass lathe (112) for holding and rotating the core rod/barrier tube combination, at least one heater (118) for uniformly heating he combination, and a gas and/or vacuum introducing device (209) to the space formed between the core (22) and the barrier tube (28).