This part of IEC 60793 establishes uniform requirements for measuring the cut-off wavelength of single-mode optical fibre, thereby assisting in the inspection of fibres and cables for commercial purposes.
This standard provides methods for measuring the cut-off wavelength of cable, fibre, and jumper cable.
Two methods exist for measuring cable cut-off wavelength, λ cc:
– method A: using uncabled fibre;
– method B: using cabled fibre.
There is only one method for measuring fibre cut-off wavelength, λ c.
There is only one method for measuring jumper cable fibre cut-off wavelength, λ cj.
The test method in this standard describes procedures for determining the cut-off wavelength of a sample fibre in either an uncabled condition (λ c) or in a cable (λ cc) or as a jumper cable (λ cj). Three default configurations are given here: any different configuration will be given in a detail specification. This method applies to all B fibre types.
All methods require a reference measurement. There are two reference-scan techniques, either or both of which may be used with all methods:
– bend-reference technique;
– multimode-reference technique.
