Abstract

Germanium-doped optical fibers and preforms are found to fluoresce at a wavelength near 420 nm when excited by UV radiation at a wavelength below 350 nm. The UV absorption spectrum of a preform sample was measured and found to exhibit a strong and relatively broad peak in the vicinity of 240 nm. Experimental results of the application of this effect to the refractive-index profiling of multimode optical fiber preforms is presented. In this application the preform is excited transversely to its axis by a He–Cd laser emitting at a wavelength of 325 nm. The resulting fluorescent radiation is detected by a video camera to give the concentration profile directly. The effects of boron and phosphorous dopants on the profile are also shown.

© 1981 Optical Society of America

Fluorescence profiling of single-mode optical fiber preforms

Herman M. Presby
Appl. Opt. 20(3) 446-450 (1981)

Ultraviolet analysis of graded-index lightguide preforms

Nicole Levy
Appl. Opt. 20(3) 460-464 (1981)

Refractive-index profiling of single-mode optical fibers and performs

Herman M. Presby, Dietrich Marcuse, and William G. French
Appl. Opt. 18(23) 4006-4011 (1979)

Preform core diameter measurement by fluorescence

Herman M. Presby and Dietrich Marcuse
Appl. Opt. 20(24) 4324-4328 (1981)

Ultraviolet absorption studies of germanium silicate glasses

M. Josephine Yuen
Appl. Opt. 21(1) 136-140 (1982)