Polishing of the edges of the optical connector ferrules determines in many respects the quality of the optical connection. That's why, it is very important to examine the quality of polishing by means of a microscope. Check for microscratches and the glue residues on the ferrule and fiber. Fiber shift, deep shearing or, vice versa, the insufficiently processed edge may be observed. If polishing is performed well, a uniformly dark (or uniformly light) inner circle may be seen in the microscope.
Good quality of polishing | |
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Satisfactory quality of polishing | ||
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| Glue residues and dirt may be seen | Glue residues may be seen; the fiber core is inconsiderably damaged | |
Inadequate quality of polishing | ||
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| Alcohol stains may be seen clearly | The fiber is shifted to the edge of the glue channel (glue crescent from the left) | |
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| Numerous scratches resulting from overpolishing using coarse polishing paper | A shearing at the fiber core | |
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| Dirt may be seen | Excess adhesive, scratches | |
