Optical transport fibre and method for producing same
An optical fiber for transmitting laser beams includes at least one fiber core, at least one fiber jacket, a sheath encompassing the fiber jacket, an interlayer between the fiber jacket and the sheath, in which the refractive index of the interlayer is lower than a refractive index of the corresponding fiber jacket that is in contact with the interlayer, and an outputting means for outputting leakage radiation from the fiber.
1. An optical fiber comprising:
at least one fiber core;
a first fiber jacket;
a sheath encompassing the first fiber jacket;
an interlayer between the first fiber jacket and the sheath, wherein a refractive index of the interlayer is lower than a refractive index of the first fiber jacket;
a plug positioned near an end of the optical fiber, the plug being arranged around a contact spot on the optical fiber and being connected to the optical fiber by an adhesive that contacts the interlayer along a longitudinal direction of the optical fiber,
wherein the interlayer prevents radiation from escaping the fiber at the contact spot; and
at least one outputting means device for outputting radiation out of the first fiber jacket.
2. An optical fiber according to claim 1 , wherein the at least one outputting device comprises a tarnished portion of the fiber, and wherein the interlayer is removed in the area of the tarnished portion of the fiber.
3. An optical fiber according to claim 1 , wherein a thickness of the interlayer is less than 20 μm.
4. An optical fiber according to claim 3 , wherein the thickness of the interlayer is in a range between 5 to 10 μm.
5. An optical fiber according to claim 1 , wherein the fiber comprises a second jacket that is in contact with the first fiber jacket and arranged around the first fiber jacket.
6. An optical fiber according to claim 1 , wherein the fiber is a single-mode fiber.
7. An optical fiber according to claim 1 , wherein the fiber comprises a plurality of fiber cores.
8. An optical fiber according to claim 1 , wherein the outputting device is located at a position on the fiber before the contact spot with respect to a propagation direction of the light along the fiber.
9. A method for manufacturing an optical fiber, the method comprising:
forming a fiber core;
forming at least one fiber jacket around the fiber core;
forming a sheath arranged around the at least one fiber jacket;
forming an interlayer, the interlayer being located between the at least one fiber jacket and the sheath and at a contact spot of the optical fiber, the interlayer having a refractive index that is lower than a refractive index of the at least one fiber jacket,
wherein the interlayer prevents radiation from escaping the optical fiber at the contact spot;
arranging a plug around the contact spot near an end of the optical fiber; and
connecting the plug to the optical fiber through an adhesive that contacts the interlayer along a longitudinal direction of the optical fiber.
10. A method according to claim 9 , further comprising forming an outputting device on the fiber for outputting leakage radiation from the at least one fiber jacket.
11. A method according to claim 10 , wherein forming the outputting device comprises etching away the interlayer.
12. A method according to claim 9 , further comprising:
removing a portion of the sheath at the contact spot such that a part of the interlayer forms an exposed surface of the fiber; and
arranging the adhesive around the exposed part of the interlayer.
13. A method according to claim 12 , wherein the portion of the sheath is removed such that, during bonding, the sheath protrudes into the contact spot.