Abstract

Dispersive differences between B₂O₃ and SiO₂ constituents make nonparabolic profiles optimal equalizers of intermodal group delays in fibers with graded B₂O₃–SiO₂ cores and uniform B₂O₃–SiO₂ cladding. Pulse dispersion measurements were correlated with profile shapes in a systematic study of multimode fibers with near power law gradients. Far field spatial ray filters were used to diagnose impulse response shapes so that new fibers could be fabricated with closer-to-optimal profile gradients. One of the fibers had an α ≈ 1.77 power law exponent that was nearly optimal for λ = 907.5-nm wavelength and caused 2σ = 0.26-nsec/km full rms output pulse spreading. When expected material dispersion effects were deconvolved from the output pulse spreading, the resultant pulse width was approximately 75 times less than the result expected for a comparable step-index fiber. This is the largest pulse width reduction reported yet.

© 1976 Optical Society of America

Graded index fiber waveguides with borosilicate composition: fabrication techniques

W. G. French, G. W. Tasker, and J. R. Simpson
Appl. Opt. 15(7) 1803-1807 (1976)

Pulse separating in transmission characteristics of multimode graded index optical fibers

Masahiro Ikeda and Haruo Yoshikiyo
Appl. Opt. 15(5) 1307-1312 (1976)

Pulse broadening in graded-index optical fibers

Robert Olshansky and Donald B. Keck
Appl. Opt. 15(2) 483-491 (1976)

Binary silica optical fibers: refractive index and profile dispersion measurements

H. M. Presby and I. P. Kaminow
Appl. Opt. 15(12) 3029-3036 (1976)

Pulse delay measurements in the zero material dispersion wavelength region for optical fibers

L. G. Cohen and Chinlon Lin
Appl. Opt. 16(12) 3136-3139 (1977)