Figure 2. Refractive index profile of multimode fiber with low DMD, optimized for operation under VCSEL (λ=850nm) excitation with central launch

From

Design of Refractive Index Profile for Multimode Optical Fibers with Low Differential Mode Delay

Anton V. Bourdine

Journal of Optoelectronics Engineering. 2013, 1(1), 5-13 doi:10.12691/joe-1-1-2