| 摘要 |
The present invention is directed at a lightguide, at a method of making the lightguide, and at a method of using the lightguide for stable transmission of UV light. The lightguide includes a core, a cladding overlying the core, and a resistive element overlying the cladding for elevating the temperature of the fiber. The resistive element has sufficient resistance to produce heat when conducting electric current. Alternatively, the fiber can be heated by irradiating the core with IR light at an OH absorption wavelength. Both these means for heating the lightguide can be enhanced if the cladding consists of a microporous silica layer. Moreover, the UV transmission properties of the fiber are further enhanced by impregnating the microporous silica layer with hydrogen or deuterium gas. A preferred embodiment of the invention also uses a hermetic coating over the microporous silica layer to retard the diffusion of the gas from the fiber. <IMAGE> |
