Apparatus for cooling an optical fibre drawn from a preform

摘要

Embodiments of the invention include an apparatus and method for drawing optical waveguide fiber. The apparatus includes a furnace for heating an optical waveguide preform passing therethrough and a cooling chamber coupled to the furnace for cooling optical waveguide fiber drawn from the preform after it passes through the furnace. The cooling chamber is configured to allow passage therethrough of a glob of molten glass formed by the molten end of the heated preform prior to the formation of optical waveguide fiber. Alternatively, the apparatus also includes a transitional cooling tube for additional cooling of the drawn waveguide fiber and for coupling an annealer to the cooling chamber that likewise is configured to allow passage of the formed glob of softened glass. The method for drawing optical fiber comprises heating an optical fiber preform in a furnace as the preform passes therethrough, drawing optical waveguide fiber from the heated preform, and cooling optical waveguide fiber as it exits the furnace by passing it through a cooling chamber extending downward from the furnace. Unlike conventional cooling chambers, the cooling chamber is configured to allow passage therethrough of the glob of molten glass formed by the molten end of the heated preform prior to formation of optical waveguide fiber.