Fibre characterisation has been a part of my career since I joined York Technology in 1983. York had developed the FCm 1000, the first automatic fibre characterisation machine. This mighty machine could measure all of the fibre’s critical parameters, including end face geometry, mode field diameter and refractive index profile, as well as perform optical time-domain reflectometer (OTDR) testing, spectral attenuation measurements and, for multimode fibres, find the modal dispersion.

As data rates increase across fibre networks, optical loss budgets are being driven down - attenuation through the system must be lower than ever because there is less tolerance for overall loss of light.