1 Scope
This part of IEC 60793‑2 is applicable to category A4 optical multimode fibres and the related sub-categories
A4a, A4b, A4c, A4d, A4e, A4f, A4g and A4h. These fibres have a plastic core and plastic
cladding and may have step-index, multi-step index or graded-index profiles. The fibres
are used in information transmission equipment and other applications employing similar
light transmitting techniques, and finally in fibre optic cables. Table 1 summarizes some of the salient characteristics and applications of these fibres.
Table 1
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Characteristics and applications of category A4 fibres
| Sub-category | A4a | A4b | A4c | A4d | A4e | A4f | A4g | A4h |
|---|---|---|---|---|---|---|---|---|
| Core diameter (µm) | See Note 1 | See Note 1 | See Note 1 | See Note 1 | ≥ 500 | 200 | 120 | 62,5 |
| Cladding diameter (µm) | 1 000 | 750 | 500 | 1 000 | 750 | 490 | 490 | 245 |
| Numerical aperture Naff | 0,50 | 0,50 | 0,50 | 0,30 | 0,25 | 0,190 | 0,190 | 0,190 |
| Operating wave- length (s) (nm) |
650 See Note 2 |
650 | 650 | 650 | 650 | 650
850 1 300 |
650
850 1 300 |
850 1 300 |
| Applica-tions | Digital audio interface, automobile, industrial, sensor and data transmission | Indus- trial and sen-sor | Sen-sor | Digital audiovisual interface and data transmission | Digital audiovisual interface and data transmission | Industrial and mobile; compatible with A3 transmission equipment | Data transmission | Data transmission; primarily used in ribbon structures |
NOTE 1 Typically 15 µm to 35 µm smaller than the cladding diameter.
NOTE 2 Other potential wavelengths for A4a fibre are described in Annex J.
In addition to the applications shown in Table 1, other applications for A4 fibres include, but are not restricted to, the following:
support for short reach, high bit-rate systems in telephony, distribution and local
networks, carrying data, voice and/or video services and on-premises intrabuilding
and interbuilding fibre installations, including LANs, PBXs, video, various multiplexing
uses and miscellaneous related uses, such as consumer electronics and industrial and
mobile networks.
Three types of requirements apply to A4 fibres:
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• general requirements, as defined in IEC 60793‑2;
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• specific requirements common to category A4 multimode fibres covered in this standard and which are given in Clause 3;
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• particular requirements applicable to individual fibre sub-categories and implementations or specific applications which are defined in this standard, in the normative family specification annexes.