Side-detecting optical fiber doped with Tb3+ for ultraviolet sensor application

Abstract

In the article a novel construction of a side-detecting luminescent optical fiber for an UV sensor application has been presented. In the fiber, structure phosphate glass doped with 0.5 mol% Tb3+ ions was used as a UV sensitive core/ribbon. The luminescence spectrum of glass and the optical fiber was measured under UV excitation using a deuterium lamp. It was found that large energy gap between upper (metastable) and lower (ground) levels of terbium ions incorporated in phosphate matrix leads to the effective emission at wavelengths of 489, 543, 586 and 621 nm, which correspond to 5D4 → 7FJ, (J = 3, 4, 5, 6) transitions respectively. Phosphate glass doped with optimal (the strongest VIS emission) concentration of Tb3+ (0.5 mol%) was used as the active core/ribbon in the construction of UV side-detecting optical fiber.