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We have over 60 years of combined experience with film and the polishing process. We work closely with our customers to develop and resolve process control issues.

Diamond for coarse grinding and refining

  • Prevent unacceptable fiber height as it removes material and fiber at the same rate

66P Diamond Lapping Films are designed to provide consistent high-quality surface finishes in lapping applications for hard surfaces. This product series is particularly suitable for metallography sample preparation but also finds use in lapping and superfinishing of other hard materials including ceramics, semiconductors, glass, metals, and stone. To ensure high quality and reliable performance, 66P Lapping Films are made by precision-coating tightly graded diamond particles onto a 3-mil polyester substrate.

***Available in discs, sheets, and rolls, with or without pressure-sensitive adhesive (PSA).


Superfinishing, precision lapping, and fining of hard materials, including hard metal alloys, ceramics, glass, semiconductors, stone, and other hard materials.

Regardless of the connector type, most polishing sequences begin with aggressive materials, including silicon carbide, to remove epoxy and diamond lapping films for beginning and intermediate polishing. These remove both surrounding material and fiber at the same rate. The last polishing step, however, requires a less aggressive material, such as silicon dioxide, to attack only the fiber. Using material for final polishing that is too aggressive could lead to excessive undercut. The wrong final-polish material also could cause excessive protrusion, leading to fiber chipping and cracking during the connector mating process.

Tips for limiting fiber protrusion and undercut

Cleanliness also can affect yield. Thorough cleaning of connectors between processing steps, as well as rapid changing of polishing plates, can help reduce cross-contamination and subsequent back-reflection problems.

End-users must select film type, make, and particle size. Excessively aggressive films can destroy a 125-μm fiber, as well as the end-face radius.

Epoxy removal is also essential to contamination-free polishing. Some epoxies can be removed more easily with specific grades of silicon-carbide polishing films. The films to use in this step depend on the epoxy type and the size of the epoxy bead mounted on the connector end face. Epoxies will have varying hardness levels; some will be tacky, some firm. Films with coarser particle sizes (20 and 30 μm) remove hard epoxies easily, while films with smaller particles (9 and 5 μm) are better suited to softer epoxies.

Importance of Controlling Undercut & Protrusion

Film – Polishing Process – Geometry – epoxy removal


  • Causes Back reflections
  • Internal connector reflections can cause spurious modulations and noise Feedback.
  • Reflection noise is an important concern in analog video


  • Submicron measurements of differential height by reflecting monochromatic light off a surface and combining with light reflecting off a standard to form constructive and destructive interference patterns.
  • Causes Fiber Pushback and affects long-term performance

Interferometry Helps

Submicron measurements of differential height by reflecting monochromatic light off a surface and combining with light reflecting off a standard to form constructive and destructive interference patterns

PC Polish

Fibers meet in intimate optical contact (no air gap)

Fibers compress until ferrule contact

Fiber takes a majority of the Compressive Force

Why Use Interferometry

  • Quality Control of connectors
  • Inspect for scratches
  • Measure light loss
  • Back reflection if necessary
  • Interferometry checks 3D polish geometry.
  • Assures consistency
  • Assures long-term performance
  • Detailed information = more control over the process
    • Effects to consider:
    • Temperature cycling
    • Contact pressure
    • Vibration

Again, we offer a polishing film that is cost-effective and works.  Create a FREE CHAT and/or set up a FREE CALL to discuss your application.  All of our support TEAM has been working with polishing, film, and/or interferometry since the ’90s.  *We provide FREE evaluation sample Film when available for Polishing Process evaluation and confirmation. 

The basic polishing process involves these steps:

  1. Epoxy Removal
  2. Geometry
  3. Final Step: finishing the optical surface
  4. assembly

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