Patent ID: 11966079
Assignee: HITACHI ENERGY LTD
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 12:
13. The spliced optical fiber according to claim 1, wherein the spliced optical fiber is formed by connecting two polarization-maintaining optical fibers, against mechanical stress and/or moisture, the splice of the spliced optical fiber protected by a process comprising:
step a) positioning the spliced optical fiber into the protection tube, wherein the protection tube has such a length that the splice is located inside it at least at the predefined minimum distance from a first end and a second end of the protection tube;
step b) sealing the first end of the protection tube around the spliced optical fiber by applying heat to a first outer dual-shrink sleeve arranged around a portion of the first end of the protection tube and a portion of the spliced optical fiber, thereby shrinking the first outer dual-shrink sleeve onto said portions; and subsequently
step c) sealing a capillary sleeve around a portion of the spliced optical fiber in an area of the second end of the protection tube, wherein the capillary sleeve is positioned at least partially inside the protection tube, by applying heat to an inner dual-shrink sleeve arranged around a portion of that end of the capillary sleeve, which is nearest to the splice, and around a portion of the spliced optical fiber; and
step d) sealing the second end of the protection tube around the spliced optical fiber by applying heat to a second outer dual-shrink sleeve arranged around a portion of a second end of the protection tube and a portion of the spliced optical fiber, thereby shrinking the second outer dual-shrink sleeve onto said portions;
or:
leaving out step b) and applying the sealing steps c) and d) at both the first end and the second end of the protection tube,
or:
leaving out steps b), c) and d) and instead injecting an adhesive material into the protection tube at both the first end and the second end of the protection tube.