coated fiber includes an optical fiber a first polymer coating generally concentrically surrounding the optical fiber and a second polymer coating generally concentrically surrounding the first polymer coating wherein the first polymer coating includes substantially no coefficient of thermal expansion stresses when the optical fiber is placed at a lower end of the temperature range application_number US 25146202 A description referring to fig1 and 2 there is shown an apparatus 10 for manufacturing a coated optical fiber having a plurality of polymer coatings disposed concentrically about the fiber core as shown in fig1 an optical fiber 12 provided with a first photopolymerizable coating disposed concentrically about the fiber core is exposed to actinic radiation e g ultraviolet or visible radiation from a lamp 14 to polymerize the coating examples of suitable materials for the first coating include relatively flexible polymers such as acrylate functional silicone polymers the particular type of actinic radiation and the exposure conditions are selected based upon the particular photopolymerizable coating employed once polymerization is complete the coated optical fiber may be cooled at a cooling station 16 by exposing the coated fiber to a chilled stream of gas preferably the gas is inert with respect to the coated fiber a number of gases can be used including helium nitrogen argon carbon dioxide and combinations thereof because helium has a high thermal conductivity it is particularly effective for cooling the coated fiber the gas may be cooled e g by running it through a coil of copper tubing submerged in a dry ice propanol bath cooling the coated fiber prior to application of the second photopolymerizable coating.