MPO (Multi-Fiber Push-On) polishing process - Lapping Film Manufacturer XYT

The MPO (Multi-Fiber Push-On) polishing process is a critical procedure to ensure optimal performance of fiber optic connectors by minimizing insertion loss and back reflection. Below is a structured overview of the process, including key steps, considerations, and best practices:

MPO Polishing Process Overview

1. Purpose
   Achieve smooth, defect-free end faces on MPO ferrules to ensure reliable optical connections with low signal loss and reflectance.
2. Key Steps
   Inspection:
   Use a microscope (200x–400x) or video probe to check for scratches, pits, or contamination.
   Replace damaged ferrules before polishing.
   Cleaning:
   Clean ferrule end faces with lint-free wipes and isopropyl alcohol (IPA) to remove debris.
   Polishing Film Selection:
   Progressively finer grits: Start with SC15B Silicon Carbide coarse (15 µm) for material removal, then SC3D Silicon Carbide Intermediate polishing 3 µm, SC1A Silicon Carbide fine (1 µm) for finishing and fiber height adjust, and CE0.5B final polishing ultra-fine 0.5 µm.
   Machine Setup:
   Secure MPO connector in a fixture aligned to the polishing machine.
   Ensure even pressure distribution across all fibers (typically 1–2 lbs).
   Polishing Stages:
   Coarse Polish: Remove bulk defects (e.g., epoxy).
   Intermediate Polish: Refine surface with medium grit.
   Fine Polish with Fiber Height Adjust: Refine surface with fine grit and adjust the fiber height. Final Polish: Achieve optical-quality finish.
   Clean thoroughly between stages to avoid cross-contamination.
   Final Inspection:
   Use microscopy to check for scratches (per IEC 61300-3-35 standards).
   Test geometry (radius of curvature, apex offset) with an interferometer.
   Measure insertion loss (<0.5 dB) and return loss (>50 dB for APC) with an optical loss test set.
3. Critical Considerations
   Pressure/Time Control: Over-polishing causes undercutting; under-polishing leaves scratches.
   Contamination Avoidance: Work in a clean environment to prevent particle embedding.
   Ferrule Material: Ceramic ferrules may require diamond films; softer materials polish faster.
   APC vs. PC: Angled (APC) connectors need angled fixtures (8°) to reduce back reflection.
4. Common Issues & Solutions
   Undercutting: Reduce pressure/time; check fixture alignment.
   Scratches: Use fresh films and proper grit progression.
   Contamination: Replace worn pads and maintain a dust-free workspace.
5. Quality Standards
   Geometry: Radius of curvature (10–25 mm), apex offset (<50 µm).
   Surface Defects: No scratches exceeding Telcordia GR-326 or IEC standards.
   Performance: Insertion loss <0.5 dB, return loss >50 dB (APC).
6. Tools & Environment
   Automated polishing machine, interferometer, inspection microscope.
   Cleanroom or laminar flow bench for single-mode applications.
7. Safety & Training
   Handle fiber fragments carefully; use PPE with chemicals.
   Train operators on machine setup, defect recognition, and standards.

Summary

The MPO polishing process combines precise mechanical abrasion, rigorous cleaning, and meticulous inspection to produce connectors that meet high-performance standards. Proper execution ensures reliable high-speed data transmission in telecom and datacom networks.

For more information on XYT's high-quality lapping films, visit our website at polishingfilm.com or contact us at sales@xytbrands.com | +8615702088819.