Ultraviolet curing system and bulb

Abstract

The present invention is an apparatus for curing an article that is passing through the apparatus, wherein the article is being cured by ultraviolet radiation curing. The present invention most commonly applies to the field of fiber optics, and the manufacture of optical fibers and fiber optic cables or ribbons. The present invention comprises a hollow tubular UV light emitting device (bulb) and a UV transparent tube where the bulb is disposed around the tube creating a space between the tube and the bulb. The article to be cured passes through the center of the tube along with an inert gas, where the inert gas is either cooled or heated depending on the application of the apparatus. A UV transparent cooling medium is passed through the space between the tube and the bulb to provide cooling for the apparatus, preventing heat damage from the bulb. Shielding coatings are employed on either the surface of the tube or the inner surface of the bulb to prevent harmful and unwanted radiation from the bulb from reaching the article to be cured. Further, a dichroic reflector is employed outside of the bulb to reflect UV radiation back into the bulb while allowing other radiation emitted by the bulb to escape, while the exterior of the bulb is being cooled by an additional cooling medium passing over the exterior of the bulb. The present invention greatly improves temperature control and operational efficiency of the UV curing process over prior art devices.