Why do we need a DMD test report?

OM3 optical fiber testing method in compliance with ISO/IEC 11801 and EIA/TIA 2017-aaac-DMD Testing

Problem:

Is it necessary to verify that the 50 μm laser-optimized Optical Fiber meets the OM3 Specification through a DMD test?

Answer:

Yes. The requirements for testing methods are clearly defined in the requirements for OM3 optical fiber at 850nm with a 2000 MHz-km effective mode bandwidth of 50 µm optical fiber. The following points can fully demonstrate that the differential mode delay DMD measurement is required to demonstrate whether it meets the requirements of ISO/IEC OM3 and TIA/EIA laser-optimized multimode optical fiber.

1. ISO/IEC 11801 Ed. 2-2002 Information Technology-user building generic cabling in table 27 sets out the DMD testing method and is implemented on OM3 optical fibers. Reference: "The effective laser emission bandwidth is determined based on the differential mode delay DMD defined in IEC/PAS 60793-1-49 ."

2. IEC/PAS 60793-1-49 is now published as IEC 60793-1-49 Ed.1.0 Optical Fiber-Chapter 1-49: measurement methods and test procedures-differential mode latency.

3. for 850-nm laser optimization, the detailed specification of 50/125 μm gradient refraction Multimode Optical Fiber TIA/EIA 2017-aaac-2002 specifies the use of TIA/EIA-455-220 (FOTP-220) multimode optical fiber differential mode delay measurement, in order to prove the bandwidth characteristics of the mode and implement the specifications of the DMD according to the measurement. According to Clause 4.4.9 of table 3-AAAC: "At 850nm, The FOTP-220 test program is used to test the latency of the differential mode, and the effective mode bandwidth reaches 492 MHz • km performance level is confirmed ."

4. IEC 60793-1-49 is an international standard document equivalent to TIA/EIA-455-220. Therefore, all reference values must comply with the same DMD measurement requirements.

5. the IEEE 802.3ae Standard Optical Fiber for 10 Gbit/s Ethernet refers to the optical fiber that complies with the mode bandwidth defined in the TIA/EIA-492-AAAC-2000 table 52-25 as 2000 MHz-km.