WEBINAR: Insertion Loss and Return Loss Testing of Complex Cable Assemblies

In this webinar, we explore simple test setups to accurately measure IL and RL for various non-standard and emerging cable assemblies including: hybrid patch cords, unibody duplex (SN and MDC), shuffles, loopbacks, and expanded beam connectors. We will also look at the new 3M expanded beam EBO connector in detail and show features that make it optimal for connectivity and installation.

Skip ahead to:
Testing Hybrid Cables 5:21sec
Mini Duplex Unibody Connectors 11:01sec
Fiber Optic Loopback Components 16:52sec
Testing Loopback Assemblies 17:41sec
MPO Loopback Testing 19:33sec
Shuffle Testing 22:29sec
Expanded Beam Connectors 27:28sec

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Does swapping the OPM adapters during the hybrid cord test affect the reference?

For the most part, no. Swapping adapters purchased from the same manufacturer, and intended for the same purpose, from one OPM to the next does not invalidate the reference. Be cautious when using adapters acquired from different manufacturers. 

With the large cord method, does the "zero loss contribution" apply to both IL and RL?

When we say “zero loss contribution” from the large core method, this is specific to IL. Back reflection does occur when mating to the large core receive cable. With a pulse based RL measurement, the reflection from the back connector does not contribute to the RL measurement of the front connector if they are an appropriate distance apart. With the CW method, the reflection from the back connector will affect the RL. 

Is there a multifiber (MPO/MTP/...) reference on the market and is it standardized?

There is currently no standard, but there are suggested geometry standards, as well as recommended IL and RL performance for reference cords. Contact OptoTest for more information. Contact OptoTest for more information.

For RL measuring, what is considered a reference connector? Is it a connector with a known RL?

This depends on the manufacturer of the connector in question, as they typically have their own requirements. 

How is polarity validated with the large area detector using the de-shuffle test method?

If the de-shuffle is constructed properly, the output power is only read by the OPM if the mapping of the shuffle is correct. With that said, the de-shuffle method cannot identify what the mapping is. In other words, verification is possible but not identification. 

Are there single channel versions of the EBO ferrule?

There is no single channel version of the EBO ferrule.

How do you keep the TIR mirror surface clean?

There is a film that covers the TIR surface.

Should the MM receive cord be made of BIMMF or non-BIMMF fiber?

We generally recommend that non-BIMMF cables be used, particularly with regards to launch conditions and total link loss measurements. If the sole consideration is for the large core receive cable, the main thing is to ensure a large enough core size and NA regardless of fiber type.

What large core receive fiber is recommended for a 62.5 µm DUT?

We recommend 100/140 µm graded index for the receive cable. There is a standard 100/140 µm GI fiber with 0.29 NA. 

Do the EBO connectors have the same performance at 1310nm and 1550nm when using 9 µm SM fiber?

The performance is similar. IL at 1550nm may be 0.1–0.15dB higher but very similar overall. RL is also similar. 

Why does a larger NA result in zero loss when mating to the large core receive cable?

By using the larger core with higher NA, the acceptance angle range on the receive side is larger than the angle range of light transmitting from the DUT connector. This large range of acceptable angles on the receiving side allows all the light coming from the DUT connector to be absorbed. 

What is the difference between the integrating sphere and the large area detector for this application?

With the large area detector, light shines directly onto the detector. With the integrating sphere, the light is scattered uniformly within the sphere cavity and then absorbed by the OPM.