Fiber Optic Feedthrough

A company contacted BCE to design a fiber optic feedthrough for their new assembly. They required (4) x 100 inch single mode coupler fibers to reach a narrow area within their assembly. The customer had a difficult time finding a compatible solution due to the specific thread type and the long fiber length so they approached BCE to create a custom feedthrough. Due to the sensitive nature of fiber optic cable, a BCE Epoxy Feedthrough was the optimal solution.

REQUIREMENTS:

4x single mode Acrylate coated fibers
¾”-16 threaded 316 SS fitting
Helium leak test: 5 x 10-8 atm-cc/s or better
Temperature range: 0°C - 65° C
Long lead length ~100”

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OUTCOME

The small outer diameter (245 µm with an 8 µm core) of the fibers and the long length, required the addition of Hytrel furcation tubing to prevent breakage by reducing the bend radius. This created a robust feedthrough to withstand a wide range of vacuum and temperature conditions. The fiber optic feedthrough exceeded expectations and achieved a 10 x 10-10 atm cc/s helium leak rate.

For more information, contact BCE. Call them at 510-274-1990 or visit their web site at https://bcemfg.com.