QUESTION:
Is there a solution for getting LC/PC for return loss more than 60 dB? If it depends on final polishing film, is Ultimas final polishing film suitable? What kind of films will work? Is there a special polishing method?
ANSWER:
Unfortunately, there isn’t a special final film that produces 60 dB on UPC connectors. Our film is the most likely to get you there, but many other factors need to be considered including test leads on the RL meter. However, I dare say getting 60 dB with a decent yield, may not be doable without considerable scrap. Also, ultra-low return loss degrades with multiple mates, so you need to get it under the first test. Consider that you may test -60.5 dB on the first test with ‘fresh’ test leads, but if the customer tests the next time with the best test leads, it may be -59 dB, then -57 dB, then finally settle somewhere below that.
Here are a few additional comments:
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In terms of polishing process, there’s not much more that can be done with current state of lapping films.
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To tweak out the last few dB’s, you need to focus on core alignment (highest concentricity ferrules and fibers, and most precise adapter split-sleeves) that can be found.
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RL values are not a characteristic of the connector itself, but of the mated pair. A RL limit of 60 dB in production will mean you’ll need to constantly replacing test leads. The end user will likely not be able to correlate results.
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If end user truly needs 60’s, APC’s are the way to go.
ADDITIONAL CONTENT & RESOURCES:
- Category Resource: FOC Film Page
- Find More Information in this Blog: Polishing Tips and Best Practices for Single Fiber Connectors
- Find More Information in this Blog: Why Do Scratches Appear After Using the Final Film?
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