When polishing an MT ferrule, it is virtually impossible to polish an array of fibers to EXACTLY the same heights. There will always be some deviation in height between fibers in the array. But, when the fibers and ferrule are mated and under load, they undergo a degree of compression/distortion that allows for sufficient fiber-to-fiber contact to be achieved, as long as the fiber height variation is not TOO much.
How much fiber height variation is “too much”? This is (among other characteristics) what the standards bodies attempt to define (see IEC 61755-3-31:2015). Originally, the fiber height variation specifications set forth by IEC involved only max-min heights of all fibers, and the height differences between adjacent fibers. Recently, Minus Coplanarity was added to the specification.
Additional resources from the FOC team include:
- Category Resource: FOC Polish Page
- Glossary, Acronyms, Military Specifications for Connectors: http://bit.ly/2a2EFn8
- Q&A Resource: email technical questions to AskFOC@focenter.com
Have questions about this FOC Tip?
Contact FOC with questions at: (800) 473-4237 / 508-992-6464 or email: FiberOpticCenter@focenter.com and we will respond ASAP.