Patent ID: 7561771

Claim:
A method of installing a double ended distributed sensing optical fiber assembly within a guide conduit, the method comprising: providing a distributed sensing optical fiber assembly having a first elongate section with a first proximal end and a first distal end, and second elongate section with a second proximal end and a second distal end; providing a nose section, which interconnects the first proximal end to the second proximal end such that light transmitted along the length of one section of fiber optical cable is transmitted via the nose section into the other section of fiber optical cable; inserting the nose section into the guide conduit such that the nose section moves through the guide conduit ahead of the first elongate section and second elongate section; and connecting the first distal end and second distal end to a light transmission and receiving unit; wherein the nose section has an outer width which is less than 1 cm and the nose section, the first elongate section, and the second elongate section are formed from a single fiber optical cable that which is bent into a U-shaped configuration in a region of the nose section and the fiber optical cable is stretched in the region of the nose section such that the fiber optical cable has a smaller width in the region of the nose section than in most other parts of the fiber optical cable; and wherein the fiber optical cable is heated when it is stretched and the bent section of stretched fiber optical cable is embedded in a nose-shaped body of material having a lower light reflection index than the stretched fiber optical cable embedded therein.