Minus Coplanarity is simply the distance between the lowest fiber and the “best-fit plane” through the array of fibers (also called the “fiber line”). It is a measure of fiber height variation within an array of fibers. A lower number is better, with a value of “0” indicating the theoretical ideal – all fibers are EXACTLY the same height.
The best-fit plane is a line through the array of fiber protrusions calculated by using the mathematical “least square method.”. Think of it as a straight line through the array which is the best representation of all heights. The least square method is high-school math and not extremely complicated, but it is exactly the same formula used in Excel graphs when you add a linear trendline through data points.
READ THE BLOG: MT Ferrule Geometry Specifications: Minus-Side Coplanarity in IEC 61755-3-31:2015
Additional resources from the FOC team include:
- Category Resource:
- View the Glossary, Acronyms, Military Specifications for Connectors
- 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.
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