Optical fibres - Measurement methods and test procedures. Beat length Ingestion-build-183098 When this guide was circulated

When this guide was circulated to interested parties some regulatory authorities commented that they would have greater confidence in the use of symbols to replace text if the best practices set out in the Guide were in a standards document

The standard also specifies how to monitor performance

It is applicable to both periodic measurements and the calibration of automated measuring systems permanently installed on stacks

BS 4481-2 is the second part of the BS 4481 multi-series that discusses bonded abrasive products

ISO/IEC 15693-3 is the third part of an international multi-series standard that deals with cards and security devices for personal identification

Optical fibres - Measurement methods and test procedures. Beat length Ingestion-build-183098 When this guide was circulated1 Scope This part of IEC 60793 defines test methods for both the phase beat length, and the group beat length. These two parameters are defined differently, and will give different results depending on the type of polarization maintaining (PM) fibre. The phase beat length is the relevant parameter for the fibres ability to maintain a high extinction ratio. This is described in more details in Annexes A and B.