GRIN-rod lenses, ball lenses, and plano-convex rod lenses are currently proposed for fiber-optic devices. From analyses of the aberrations of these lens types it turned out that equivalent lenses in a well-designed coupling have nearly the same aberration. We derive valuable relations between the coupling efficiency and the optimal lens parameters. For each above-mentioned lens type, coupling efficiencies of 95% (0.2-dB insertion loss) can be obtained if typical communication fibers are incorporated. We also present a lens connector that has been fabricated in a factory-type production line. Its performance reaches the theoretical limits. Finally the influence of misalignments in the lens coupling system is investigated.
© 1981 Optical Society of America
A. Nicia, "Lens coupling in fiber-optic devices: efficiency limits," Appl. Opt. 20, 3136-3145 (1981)