Polishing Techniques

Polishing is a critical process in the production of high-performance fiber optic connectors. The technique applied in polishing directly affects the quality of the connector and its ability to meet various performance specifications.

Evolution of Polishing Techniques

Early fiber optic connectors were designed with flat end-faces, avoiding actual contact between fibers to prevent damage. However, as polishing techniques evolved, the concept of Physical Contact (PC) was developed. This involved creating spherical end-faces that allowed the fibers to make actual physical contact, eliminating air gaps and significantly improving light wave transmission.

The initial polishing process for singlemode PC connectors involved a four-step process: epoxy removal, ferrule forming, preliminary polish, and final polish. This was achieved using aggressive materials, typically diamond polishing films. Nowadays, with the advent of pre-radiused ferrules, the polishing process has been refined to avoid excessive disruption of the spherical surface. The modern process has reduced cycle time and adapted film gradations to suit current connector configurations, resulting in a streamlined and improved four-step process: epoxy removal, beginning polish, intermediate polish, and final polish.

Polishing Techniques for Singlemode and Multimode Connectors

The following outlines modern polishing techniques:

1. Epoxy Removal: Use finer grades of silicon carbide films for epoxy removal, minimizing disruption of the pre-formed radius.
2. Ferrule Polishing: Adapt the polishing film gradations to current connector configurations to maintain the spherical surface.
3. Fiber Polishing: Ensure a precise and smooth finish to optimize connector performance.

Machine Polishing

Machine polishing is essential for meeting the demands of increased performance and production. Manual polishing, while possible, requires highly skilled personnel and becomes impractical for stringent specifications such as SPC, UPC, and APC. Machines offer the precision and repeatability needed for ultra-precision tasks, making them the preferred choice.

A polishing machine should come with detailed instructions and a "recipe" for producing connectors that meet all specifications. The machine must be capable of incorporating new developments and supported by the manufacturer for optimal performance.

Polishing Tips & Process Considerations

1. Polishing Films

Polishing films are crucial in polishing operations. Quality and gradations vary among suppliers, and choosing the right film type, make, and particle size is essential. Aggressive films can damage fibers and disrupt the spherical radius.

Tip: Clean polishing films before and after each use to extend their life and reduce costs per connector Visit our website at www.polishingfilm.com to explore our full range of products or contact us at sales@xytbrands.com | +8615702088819 for more information.

2. Epoxy

Different types of epoxies require specific grades of silicon carbide polishing films for effective removal. The film choice depends on the epoxy type and bead size on the connector end-face.

Tip: Minimize the epoxy bead size before polishing to extend the life of polishing films. Experiment with different silicon carbide gradations to find the best epoxy removal film.Visit our website at www.polishingfilm.com to explore our full range of products or contact us at sales@xytbrands.com | +8615702088819 for more information.

3. Cleanliness 

A contamination-free environment is vital for an optimal polish. Essential items include deionized/filtered water, isopropyl alcohol, lint-free tissues, lint-free swabs, and canned air.

• Deionized/Filtered Water: Prevents foreign particles from damaging the polish.
• Isopropyl Alcohol: Cleans polishing films, connectors, and machines.
• Lint-Free Tissues: Used for applying alcohol and drying connector end-faces.
• Lint-Free Swabs: Clean reference meters and couplers to maintain accuracy.
• Canned Air: Removes debris from connectors, films, and workstations.

Tip: Periodically check and clean reference cable end-faces to prevent debris buildup and ensure accurate results.

4. Lubrication

Using deionized water, filtered water, and suspensions can enhance connector performance. The best solutions have small particle sizes (20-60nm) and should be half the size of the final polishing film.

Tip: Dilute solutions with 2 to 5 parts water to one part solution for improved performance.

Conclusion

Mechanical polishing machines provide an economical means for fiber cable manufacturers and OEMs to meet high production requirements while maintaining quality. Machine selection should be based on objective evidence of performance, references, and sample inspections. As connectors and processing techniques continue to evolve, it is crucial to have adaptable equipment and maintain effective communication with equipment manufacturers. Meeting high performance and economical manufacturing challenges ensures a prosperous future for fiber optics communications. Visit our website at www.polishingfilm.com to explore our full range of products or contact us at sales@xytbrands.com | +8615702088819 for more information.