TIA TIA-455-177-A

This part of IEC 60793 establishes uniform requirements for measuring the numerical aperture of optical fibre, thereby assisting in the inspection of fibres and cables for commercial purposes.

The numerical aperture (NA) of category A1 graded-index multimode fibre is an important parameter that describes a fibre′s light-gathering ability. It is used to predict launching efficiency, joint loss at splices, and micro/macrobending performance.