Simple feed-through for coupling optical fibres into high pressure and temperature systems

A best practice guide for assembling and testing a simple and inexpensive system feeding an optical fibre into a high pressure and temperature environment is presented. A standard Swagelok-type connector is tested together with different ferrule materials and a PEEK capillary tube as feed-through. The system proved to seal an optical fibre during several pressure and temperature cycling experiments up to 500 bar and 180 °C.