Marking defect on optical fiber during drawing, by stretching bare fiber, introducing bare fiber into cooling tube/intermediate tube, and injecting cooling gas into cooling tube with nominal flow/injecting inert gas into intermediate tube

摘要

The process comprises stretching a bare fiber, introducing the bare fiber into a cooling tube or an intermediate tube, injecting a cooling gas into the cooling tube with a nominal flow or injecting an inert gas into the intermediate tube with a nominal flow, modifying the flow and concentration of gas injected into the cooling tube or reducing the gas flow injected into the cooling tube when a defect is identified on the fiber, applying a first coating to the bare fiber, and temporarily increasing flow of gas injected into the cooling tube above the nominal flow after the creation of mark. The process comprises stretching a bare fiber, introducing the bare fiber into a cooling tube or an intermediate tube, injecting a cooling gas into the cooling tube with a nominal flow or injecting an inert gas into the intermediate tube with a nominal flow, modifying the flow and concentration of gas injected into the cooling tube or reducing the gas flow injected into the cooling tube when a defect is identified on the fiber, applying a first coating to the bare fiber, temporarily increasing the flow of gas injected into the cooling tube above the nominal flow after the creation of mark, and applying a second coating to the bare fiber for preserving the mark. The cooling gas injected into the cooling tube is modified, when a defect on the fiber during drawing is identified, to cause a variation in a diameter of the coating to create a mark in the coating for obtaining an optical fiber with a defect mark. The gas injected into the cooling tube is a mixture of gases. The gas flow injected into the cooling tube is reduced when a defect is identified on the fiber. Independent claims are included for: (1) a process for recognition of a mark on an optical fiber; (2) a fiber drawing installation; (3) an optical fiber winding installation; and (4) an optical fiber.