Abstract: To provide an optical fiber cable having a protective structure of an optical fiber connecting part that allows easy fabrication of a protective structure part having a decreased diameter without use of a metal rod and a heat-shrinkable tube, and a method for manufacturing the same.

Abstract: To provide an optical fiber cable having a protective structure of an optical fiber connecting part that allows easy fabrication of a protective structure part having a decreased diameter without use of a metal rod and a heat-shrinkable tube, and a method for manufacturing the same.

Abstract: Provided is an optical coupler, which can allow the light to be branched off by the required amount when necessary, and a method of branching light using the optical coupler. Optical coupler 1 has optical fiber 10 that has small-diameter part 12, which is formed so as to have a relatively small outer diameter at a portion in the longitudinal direction, and that branches off the transmitted light by small-diameter part 12; and output optical fiber 20 that receives the light branched off from input optical fiber 10. Small-diameter part 12 of input optical fiber 10 is caused to contact with linear small-diameter part 22 of output optical fiber 20; a coupling length, which is the length along which small-diameter part 12 of input optical fiber 10 and small-diameter part 22 of output optical fiber 20 are made to contact with each other, or a propagation constant of the optical fibers is varied; and thus, branching ratio S of the light branched off from input optical fiber 10 into output optical fiber 20 is varied.

Abstract: To provide a tapered optical fiber having a good outer diameter accuracy and a high reproducibility, a manufacturing method of the tapered optical fiber, and a manufacturing system of the tapered optical fiber. The above-mentioned problem is solved by manufacturing system 1 of a tapered optical fiber comprising: shifter 11, 12 which reciprocates optical fiber 10 mounted at positions having a prescribed distance therebetween in the longer direction X of optical fiber 10 (the direction of the optical axis); and heating device 13 which heats the reciprocating optical fiber 10 at fixed position O, wherein shifter 13 includes a broadening unit which can increase the mounting distance (L1+L2) of the optical fiber while reciprocating the optical fiber. Shifter 11, 12 has at least two mounting unit which fix the optical fiber 10, and serves as a broadening unit controlling the two mounting unit independently or interlockingly.

Abstract: To provide a tapered optical fiber having a good outer diameter accuracy and a high reproducibility, a manufacturing method of the tapered optical fiber, and a manufacturing system of the tapered optical fiber. The above-mentioned problem is solved by manufacturing system 1 of a tapered optical fiber comprising: shifter 11, 12 which reciprocates optical fiber 10 mounted at positions having a prescribed distance therebetween in the longer direction X of optical fiber 10 (the direction of the optical axis); and heating device 13 which heats the reciprocating optical fiber 10 at fixed position O, wherein shifter 13 includes a broadening unit which can increase the mounting distance (L1+L2) of the optical fiber while reciprocating the optical fiber. Shifter 11, 12 has at least two mounting unit which fix the optical fiber 10, and serves as a broadening unit controlling the two mounting unit independently or interlockingly.

Abstract: While clamped by a clamping jig 100, polarization-maintaining fiber cables 11 and 12 are automatically oriented with an orientation adjusting unit 200 and then heated by a heater 105 for curing thermoset resins.

Abstract: While clamped by a clamping jig 100, polarization-maintaining fiber cables 11 and 12 are automatically oriented with an orientation adjusting unit 200 and then heated by a heater 105 for curing thermoset resins.

Abstract: While clamped by a clamping jig 100, polarization-maintaining fiber cables 11 and 12 are automatically oriented with an orientation adjusting unit 200 and then heated by a heater 105 for curing thermoset resins.

Abstract: While clamped by a clamping jig 100, polarization-maintaining fiber cables 11 and 12 are automatically oriented with an orientation adjusting unit 200 and then heated by a heater 105 for curing thermoset resins.

Abstract: The end face of an optical fiber assembly consisting of an optical fiber s and a ferrule f is polished to form a conical surface with oblique faces Fp1 and Fp2 such that, central axis Ap of the conical surface makes an inclination of 8.degree. with respect to the optical axis L of the optical fiber s, top Ft of the conical surface coincides with the optical axis L of the optical fiber s, and has a taper angle of 2.degree.. Thereafter, the optical fiber assembly is further polished to form an oblique convex spherical surface at the end face such that, the central axis of the oblique convex spherical surface makes an inclination of 8.degree. with respect to the optical axis L of the optical fiber s. Due to this, insertion loss and light reflected back to the source is stabilized and minimized.

Abstract: End face of a ferrule 100 is polished to form a conical surface 3 such that, central axis Ap of said conical surface 3 makes an inclination of 8.degree. with respect to central axis L of optical fiber insertion hole 4, top 3t of said conical surface 3 coincides with said central axis L and has a taper angle of 2.degree.. Because of this, while polishing an end of a optical fiber inserted and fixed inside said optical fiber insertion hole 4, a well balanced oblique spherical surface can be formed and the non-coincidence of the center of said oblique convex surface with the point where said oblique convex surface intersect with the optical axis of said optical fiber can be prevented.