IEC 60793-1-41:2010 describes three methods for determining and measuring the modal bandwidth of multimode optical fibres (see IEC 60793-2-10, IEC 60793-30 series and IEC 60793-40 series). The baseband frequency response is directly measured in the frequency domain by determining the fibre response to a sinusoidaly modulated light source. The baseband response can also be measured by observing the broadening of a narrow pulse of light. The calculated response is determined using differential mode delay (DMD) data. The three methods are: – Method A – Time domain (pulse distortion) measurement – Method B – Frequency-domain measurement – Method C – Overfilled launch modal bandwidth calculated from differential mode delay (OMBc). The main change with respect to the previous edition is the addition of a third method for determining modal bandwidth based on DMD data and to improve measurement procedures for A4 fibres. This standard should be read in conjunction with IEC 60793-1-1 and IEC 60793-1-2, which cover generic specifications.<\/p>\n
| PDF Pages<\/th>\n | PDF Title<\/th>\n<\/tr>\n | ||||||
|---|---|---|---|---|---|---|---|
| 6<\/td>\n | English CONTENTS <\/td>\n<\/tr>\n | ||||||
| 8<\/td>\n | 1 Scope 2 Normative references <\/td>\n<\/tr>\n | ||||||
| 9<\/td>\n | 3 Terms and definitions 4 Apparatus 4.1 Radiation source <\/td>\n<\/tr>\n | ||||||
| 10<\/td>\n | 4.2 Launch system <\/td>\n<\/tr>\n | ||||||
| 12<\/td>\n | 4.3 Detection system 4.4 Recording system Figure 1 \u2013 Mandrel wrapped mode filter <\/td>\n<\/tr>\n | ||||||
| 13<\/td>\n | 4.5 Computational equipment 4.6 Overall system performance 5 Sampling and specimens 5.1 Test sample 5.2 Reference sample 5.3 End face preparation <\/td>\n<\/tr>\n | ||||||
| 14<\/td>\n | 5.4 Test sample packaging 5.5 Test sample positioning 6 Procedure 6.1 Method A \u2013 Time domain (pulse distortion) measurement <\/td>\n<\/tr>\n | ||||||
| 15<\/td>\n | 6.2 Method B \u2013 Frequency domain measurement 6.3 Method C \u2013 Overfilled launch modal bandwidth calculated from differential mode delay (OMBc) <\/td>\n<\/tr>\n | ||||||
| 16<\/td>\n | 7 Calculations or interpretation of results 7.1 -3 dB frequency, f3 dB Table 1 \u2013 DMD weights for calculating overfilled modal bandwidth (OMBc) from DMD data for 850 nm only <\/td>\n<\/tr>\n | ||||||
| 17<\/td>\n | 7.2 Calculations for optional reporting methods 8 Length normalization 9 Results 9.1 Information to be provided with each measurement 9.2 Information available upon request <\/td>\n<\/tr>\n | ||||||
| 18<\/td>\n | 10 Specification information <\/td>\n<\/tr>\n | ||||||
| 19<\/td>\n | Annex A (normative) Intramodal dispersion factor and the normalized intermodal dispersion limit Table A.1 \u2013 Highest expected dispersion for commercially available A1 fibres <\/td>\n<\/tr>\n | ||||||
| 22<\/td>\n | Annex B (normative) Fibre transfer function, H(f), power spectrum, |H(f)|, and f3 dB <\/td>\n<\/tr>\n | ||||||
| 24<\/td>\n | Annex C (normative) Calculations for other reporting methods <\/td>\n<\/tr>\n | ||||||
| 25<\/td>\n | Annex D (normative) Mode scrambler requirements for overfilled launching conditions to multimode fibres <\/td>\n<\/tr>\n | ||||||
| 26<\/td>\n | Figure D.1 \u2013 Two examples of optical fibre scramblers <\/td>\n<\/tr>\n | ||||||
| 30<\/td>\n | Bibliography <\/td>\n<\/tr>\n<\/table>\n","protected":false},"excerpt":{"rendered":" Optical fibres – Measurement methods and test procedures. Bandwidth<\/b><\/p>\n |