Abstract: A relay circuit board includes: a plurality of first pads arranged in parallel in a first direction; a plurality of second pads arranged in parallel in a second direction; and wirings connecting the plurality of first pads and the plurality of second pads, respectively. The second direction is inclined at a predetermined angle with respect to the first direction, and the predetermined angle is greater than 0 degree and smaller than 90 degrees.

Abstract: A wire and mold-member assembly (11, 12, 13) includes a plurality of differential transmission wires (20a to 20f) and a mold member (160, 260) situated at an end of the plurality of differential transmission wires and configured to bundle the plurality of differential transmission wires together. The mold member has a first face (160A, 260A) and a second face (160B, 260B) each intersecting with the plurality of differential transmission wires, and the second face is inclined at an angle greater than 0 degrees and less than 90 degrees relative to the first face.

Abstract: A wire and mold-member assembly (11, 12, 13) includes a plurality of differential transmission wires (20a to 20f) and a mold member (160, 260) situated at an end of the plurality of differential transmission wires and configured to bundle the plurality of differential transmission wires together. The mold member has a first face (160A, 260A) and a second face (160B, 260B) each intersecting with the plurality of differential transmission wires, and the second face is inclined at an angle greater than 0 degrees and less than 90 degrees relative to the first face.

Abstract: A relay circuit board includes: a plurality of first pads arranged in parallel in a first direction; a plurality of second pads arranged in parallel in a second direction; and wirings connecting the plurality of first pads and the plurality of second pads, respectively. The second direction is inclined at a predetermined angle with respect to the first direction, and the predetermined angle is greater than 0 degree and smaller than 90 degrees.

Abstract: A method of splicing optical fibers is provided to reduce the splicing loss of the first and second optical fibers having different MFDs from each other. In a pre-fusion heating step, the MFD at the adjacent end face of the optical fiber having larger MFD is enlarged by heating a portion including the adjacent end face thereof so as to diffuse a dopant. After the pre-fusion heating step, fusion-splicing of the first and the second optical fibers is performed. Thereafter, during the post-fusion heating step, the dopant is diffused by heating a portion including the fusion-spliced part between the first and the second optical fibers.

Abstract: The present invention relates to an optical fiber transmission line having a structure offering superior connection loss characteristics at the fusion-spliced position between optical fibers. This optical fiber transmission line has at least first and second optical fibers that are fusion-spliced. Each of these first and second optical fibers has a core region doped with 10 mol % or more of Ge and has a mode field diameter with a minimum value of 7 &mgr;m or less at the wavelength of 1550 nm. The difference between the minimum mode diameter of the first optical fiber and that of the second optical fiber is 1 &mgr;m or less.

Abstract: There is disclosed a dispersion compensator for compensating for a chromatic dispersion and dispersion slope of an optical fiber transmission line, the dispersion compensator comprising a plurality of dispersion-compensating optical fibers connected to each other, the dispersion-compensating optical fibers each having a dispersion slope compensation ratio of at least 60% with respect to the optical fiber transmission line at a predetermined wavelength, one of said plurality of dispersion-compensating optical fibers having a dispersion slope compensation ratio of at least 80%, another of said plurality of dispersion-compensating optical fibers having a dispersion slope compensation ratio within the range of 60% to 100%.

Abstract: An optical fiber has a core region and a cladding region surrounding the core region. The core region and the cladding region are made of a base material containing silica glass as a principal component. A plurality of holes extending along an axial direction are arranged at least in the cladding region. In the optical fiber, the base material has a hydroxyl mole fraction of not less than 10 ppm, or a fluorine content of not less than 0.2% by weight.

Abstract: An optical fiber (1) which does not readily suffer influences of side pressures and can realize superior transmission characteristics, having a glass part (2, 3) having a core (2) and at least one cladding (3) and at least one covering layer (4a, 4b) formed around the glass part (2, 3), characterized in that the Young's modulus at 23° C. of the covering layer (4) without the glass part (2, 3) is not greater than 400 MPa. The Young's modulus measurement of the covering layer (4) is obtained by removing the glass part (2, 3) from the optical fiber (1) and putting the covering layer (4) to a tensile test.

Abstract: An optical fiber has a core region and a cladding region surrounding the core region. The core region and the cladding region are made of a base material containing silica glass as a principal component. A plurality of holes extending along an axial direction are arranged at least in the cladding region. In the optical fiber, the base material has a hydroxyl mole fraction of not less than 10 ppm, or a fluorine content of not less than 0.2% by weight.

Abstract: The present invention relates to an optical fiber transmission line having a structure offering superior connection loss characteristics at the fusion-spliced position between optical fibers. This optical fiber transmission line has at least first and second optical fibers that are fusion-spliced. Each of these first and second optical fibers has a core region doped with 10 mol % or more of Ge and has a mode field diameter with a minimum value of 7 &mgr;m or less at the wavelength of 1550 nm. The difference between the minimum mode diameter of the first optical fiber and that of the second optical fiber is 1 &mgr;m or less.

Abstract: A method of splicing optical fibers is provided to reduce the splicing loss of the first and second optical fibers having different MFDs from each other. In a pre-fusion heating step, the MFD at the adjacent end face of the optical fiber having larger MFD is enlarged by heating a portion including the adjacent end face thereof so as to diffuse a dopant. After the pre-fusion heating step, fusion-splicing of the first and the second optical fibers is performed. Thereafter, during the post-fusion heating step, the dopant is diffused by heating a portion including the fusion-spliced part between the first and the second optical fibers.

Abstract: There is disclosed a dispersion compensator for compensating for a chromatic dispersion and dispersion slope of an optical fiber transmission line, the dispersion compensator comprising a plurality of dispersion-compensating optical fibers connected to each other, the dispersion-compensating optical fibers each having a dispersion slope compensation ratio of at least 60% with respect to the optical fiber transmission line at a predetermined wavelength, one of said plurality of dispersion-compensating optical fibers having a dispersion slope compensation ratio of at least 80%, another of said plurality of dispersion-compensating optical fibers having a dispersion slope compensation ratio within the range of 60% to 100%.