Patent ID: 8151601

Claim:
A method for drawing an optical fibre in a way that reduces the occurrence of optical fibre fractures, comprising: introducing an optical preform to a draw tower that comprises a draw furnace that is operating at a temperature of at least about 1900° C., the draw furnace having a carbon heating element, wherein the draw furnace has an inner surface that is contaminated with particles of silicon carbide (SiC) and/or silicon dioxide (SiO 2 ), and wherein the temperature of the draw furnace decreases upon the introduction of the optical preform; heating the optical preform; and drawing an optical fibre from the heated optical preform; wherein, during the step of introducing the optical preform to the draw tower, the temperature change in the draw furnace is limited to a maximum temperature increase or decrease of 15° C./minute to reduce the migration of contaminants from the draw furnace onto the optical preform and/or the optical fibre.