Design and Performance Considerations for Single-Fiber Multichannel Environmental Connectors

An eight-channel circular environmentally sealed fiberoptic connector has been developed for small diameter (125 µm) single fibers using a number 18 plug and receptacle shell from the Amphenol® Merlin^TMIII series. A brief explanation of the factors that effect coupling efficiency is offered. A loss budget is established that includes the cable-related losses associated with fiber dimensional tolerances and numerical aperture and the connector-related losses related to fiber end separation, axial and angular alignment, and Fresnel reflection. The connector design is outlined and unique features described that minimize insertion loss. The contact assembly using a MS crimp tool and a MS insertion/removal tool and the epoxy, grind, and polish procedure are outlined. Initial test results have shown a maximum insertion loss of 1.5 dB as contrasted to a maximum loss budget of 2.0 dB.