Methods of curing optical fiber coatings
AssigneeAT&T Bell Laboratories
InventorsBob J. Overton, Carl R. Taylor
Life of this patent
Estimating the term…
Abstract
Drawn optical fiber is provided with at least one layer of a coating material. The coating material typically is a UV curable material and provides the optical fiber with mechanical and environmental protection. It has been found that the temperature at which the optical fiber is cured has a pronounced effect on the modulus of the cured coating material. In order to provide a coated optical fiber of which the coating material has a desired modulus, the temperature of the coating material during cure is controlled by controlling the amount of energy of infrared wavelength which impinges on the coating material.
Claims11
A method of making an optical fiber having a layer of coating material thereon, said method including the steps of:
- drawing an optical fiber from a preform;
- applying a curable coating material to the drawn optical fiber;
- exposing the curable coating material to radiant energy to cure the coating material, the radiant energy ranging from infrared through ultraviolet frequencies with a portion thereof being effective to cure the coating material and with portions thereof having frequencies outside the range of frequencies which are used to cure the coating material and which are absorbed by said coating material thereby causing heating of the coating material;
- controlling said step of exposing the curable coating material to the radiant energy to modulate those portions of the radiant energy which are outside the useful curing range and which cause heating of the curable coating material and thereby to control the energy influx into and the heating profile of the coating material during its cure and thereby cause the modulus of cured material to be a desired value;
- and
- taking up the drawn, coated optical fiber.
The method of claim 4, wherein an infrared radiation absorbing gas also is flowed between the source of ultraviolet radiation and the tube.
A method of controlling the modulus of a curable material which is cured by exposure to ultraviolet radiation, said method including the steps of:
- exposing a curable coating material to radiant energy to cure the coating material, the radiant energy ranging from infrared through ultraviolet frequencies with a portion thereof being effective to cure the coating material and with portions thereof having frequencies outside the range of frequencies which are used to cure the coating material and which are absorbed by said coating material thereby causing heating of the coating material;
- and
- controlling said step of exposing the curable coating material to the radiant energy to modulate those portions of the radiant energy which are outside the useful curing range and which cause heating of the curable coating material and thereby to control the energy influx into and the heating profile of the coating material during its cure and thereby cause the modulus of the cured material to be a desired value.
Dependencies are inferred from the claim text.