Tool for inspecting faults from incorrectly cleaved fiber ends and contaminated optical fiber connector end surfaces

We investigated and analyzed faults in field installable connection due to incorrectly cleaved fiber ends and manufactured physical contact (PC)-type connectors with contaminated end surfaces in optical access fiber networks. The insertion and return losses of fiber connections using incorrectly cleaved fiber ends might be at worst more than 40 dB and less than 30 dB, respectively. With PC-type connectors whose end surfaces are contaminated, the insertion and return losses might be at worst 8.7 and 27 dB, respectively. We developed an inspection tool for cleaved fiber ends and connector end surfaces as a countermeasure. The proposed tool has a simple structure and does not require focal adjustment. It can be used to inspect and clearly determine whether a fiber has been cleaved correctly and whether there is contamination or scratches on the connector end surfaces. The tool requires a slight increase of 11% in operation time compared to conventional fiber end preparation and assembly procedures. The proposed tool provides a simple and cost-effective way to inspect cleaved fiber ends and connector end surfaces and is suitable for field use.