This standard is applicable to optical fibre types described in Table 1. These fibres are used for the intraconnections within or between components or photonic systems or subsystems. While the fibres are normally sold in lengths on the scale of kilometres, they are normally cut into short lengths for use in these intraconnections. While the fibres could be overcoated or buffered for the purpose of making protected pigtails, they may be used without overcoating. They may, however, be colour coded.
The general requirements defined in IEC 60793-2 apply to these fibres. Specific requirements that are common to these fibres are found in the body of this text. Particular requirements for individual fibre types or applications are defined in the normative Family specification annexes. The Family Specifications are distinguished based on optimum transmission wavelengths and nominal mode field diameter (MFD), which affects splice loss.
For each Family Specification, there are two sub-categories that are distinguished on the basis of the cladding diameter and other related attributes. The conventional nominal cladding diameter of 125 µm is augmented with the reduced cladding type product with a nominal diameter of 80 µm. These are distinguished with the suffixes: "_125" or "_80." For example C1 fibre can be selected as either C1_125 or C1_80. The transmission characteristics of the two cladding diameter choices should be the same.
For each Family Specification except C1, there are two sub-categories that are distinguished on the basis of transmission characteristics that relate to MFD. To denote these subcategories, a "_a" or "_b" suffix is added, for lower or higher MFD. In general, the fibres can be optimised for either splice loss or macrobend loss using MFD as a main variable. A C2 fibre with 80µm cladding diameter and lower MFD is designated as C2_80_a.
Fibres for the C1_125 Family Specification can be selected from Category B1.1 or B1.3 single-mode fibres and are suitable for use with any category B single-mode fibre at wavelengths from 1280 nm to 1625 nm. Fibres for the C2 and C3 Family Specifications are optimized at 1310 nm and 1550 nm windows respectively for connection to any category B single-mode fibre. Fibres for the C4 Family Specification are optimized for transporting optical amplifier pump light at 980 nm or higher.