Polishing SC, LC, FC, and ST patch cord connectors

Polishing SC, LC, FC, and ST patch cord connectors is an essential process to ensure low insertion loss and minimal return loss, especially for high-performance fiber optic systems. Each connector type has unique geometrical requirements, but the general polishing process is similar across these connectors.

Polishing Steps for SC, LC, FC, and ST Patch Cord Connectors:

1. Epoxy Removal (Initial Stage)

• Tool: Coarse abrasive lapping film (e.g., 9µm or 15µm diamond abrasive).
• Process: Remove excess epoxy, ensuring fiber tips are aligned and the ferrule is flat.
• Goal: Level the connector end-face and prepare for finer polishing.

2. Initial Polishing

• Tool: Medium grit lapping film (e.g., 6µm or 3µm diamond).
• Process: Begin shaping the fiber tips and reducing large imperfections.
• Goal: Smooth the surface and get closer to achieving the required apex offset.

3. Fine Polishing

• Tool: Finer grit lapping film (e.g., 1µm or 0.5µm diamond).
• Process: Refine the surface to remove minor scratches and imperfections.
• Goal: Achieve smooth, flat fiber tips with the correct geometry.

4. Final Polishing (Finishing Stage)

• Tool: Final Polishing Film (e.g., ADS final polishing film, typically silicon dioxide or aluminum oxide).
• Process: Perform the final pass using super-fine polishing film to achieve the desired end-face geometry and optical quality.
• Goal: Ensure a mirror-like surface for minimal light loss and reflection. Achieve proper fiber protrusion (apex offset) for optimal performance.

Connector-Specific Considerations:

1. SC Connectors:

   • Single-fiber, square ferrule.
   • Standard polishing typically uses a flat-polish or APC (angled polish) depending on the application.

2. LC Connectors:

   • Smaller form factor, often used in high-density applications.
   • Polishing must ensure that the fiber is centered within the small ferrule for optimal performance.

3. FC Connectors:

   • Screw-on type with a metal ferrule, commonly used in high-precision applications.
   • Careful polishing is needed to avoid damage to the metal ferrule while ensuring fiber alignment.

4. ST Connectors:

   • Bayonet-style connectors with a round ferrule.
   • Polishing needs to focus on ensuring a clean, flat surface with proper fiber alignment.

Important Polishing Tips:

• Pressure & Speed: Use uniform and controlled pressure during polishing to avoid damage to the fiber and ferrule. Polishing speed also affects the consistency of the finish.
• Surface Inspection: Use an interferometer or microscope to inspect the polished end-face for imperfections, fiber protrusion, and apex offset.
• Cleaning: Always clean connectors thoroughly after polishing to avoid contamination that could affect performance.

Recommended Polishing Films for SC, LC, FC, and ST Patch Cord Cables:

• Diamond Lapping Films: Used for the initial to fine polishing stages (e.g., 9µm, 6µm, 3µm, 1µm, 0.5µm, 0.25µm).
• Final Polishing Films: Silicon dioxide or aluminum oxide for the final step, ensuring a mirror-like finish and reduced fiber damage.

Would you like specific polishing film recommendations based on the connector types or further guidance on polishing equipment and techniques? Contact sales@xytbrands.com