Abstract: An optical fiber having excellent strength that can be manufactured at low cost, as well as a method for making such optical fiber, is provided. An optical fiber 1 is a silica-based optical fiber comprising a core 11, an optical cladding 12 surrounding the core 11, and a jacketing region 13 surrounding the optical cladding 12 and having a uniform composition throughout from the internal circumference to the outer circumference. A compressive strained layer having a residual compressive stress is provided at the outermost circumference of the jacketing region 13.

Abstract: An optical splicer 2 according to an embodiment of the present invention has a plurality of optical fibers 6, and an optical splice member 8 having a plurality of fiber holes 14 in each of which a portion including one end 6a of each fiber 6 is inserted, and a mode field diameter W1 in one end 6a of optical fiber 6 is enlarged relative to a mode field diameter W2 in the other portion of optical fiber 6.

Abstract: An optical splicer 2 according to an embodiment of the present invention has a plurality of optical fibers 6, and an optical splice member 8 having a plurality of fiber holes 14 in each of which a portion including one end 6a of each fiber 6 is inserted, and a mode field diameter W1 in one end 6a of optical fiber 6 is enlarged relative to a mode field diameter W2 in the other portion of optical fiber 6.

Abstract: An optical splicer 2 according to an embodiment of the present invention has a plurality of optical fibers 6, and an optical splice member 8 having a plurality of fiber holes 14 in each of which a portion including one end 6a of each fiber 6 is inserted, and a mode field diameter W1 in one end 6a of optical fiber 6 is enlarged relative to a mode field diameter W2 in the other portion of optical fiber 6.

Abstract: An optical device 1 has a substrate 2, whereas bare fibers 5 exposed from a coated optical fiber tape 3 by removing a coating 4 from its middle part are secured to the upper face part of the substrate 2. In the substrate 2, a transverse groove 8 is formed obliquely with respect to an axis of the bare fibers 5 so as to traverse core parts 5a of the bare fibers. An optical member 9 for reflecting a part of signal light transmitted through the bare fibers 5 is inserted in the transverse groove 8. A support member 10 is provided on the upper side of the bare fibers 5, whereas a support surface 10a of the support member 10 is provided with photodetectors 11 for detecting light reflected by the optical member 9. The support surface 10a of the support member 10 is inclined with respect to the upper face of the substrate 2, whereby the light entrance surface 13 of each photodetector 11 is inclined by a predetermined angle with respect to the upper face of the substrate 2.

Abstract: An optical device 1 comprises a substrate 2, whereas bare fibers 5 exposed from a coated optical fiber tape 3 by removing a coating 4 from its middle part are secured to the upper face part of the substrate 2. In the substrate 2, a transverse groove 8 is formed obliquely with respect to an axis of the bare fibers 5 so as to traverse core parts 5a of the bare fibers. An optical member 9 for reflecting a part of signal light transmitted through the bare fibers 5 is inserted in the transverse groove 8. A support member 10 is provided on the upper side of the bare fibers 5, whereas a support surface 10a of the support member 10 is provided with photodetectors 11 for detecting light reflected by the optical member 9. The support surface 10a of the support member 10 is inclined with respect to the upper face of the substrate 2, whereby the light entrance surface 13 of each photodetector 11 is inclined by a predetermined angle with respect to the upper face of the substrate 2.

Abstract: This invention relates to an optical fiber grating and a method of manufacturing the same. According to the method, a hydrogen doping process is performed before ultraviolet irradiation in order to obtain a sufficient photoinduced refractive index change. In particular, a target for the hydrogen doping process of the method is characterized by a coated fiber obtained by covering the outer surface of the bared fiber having a core region and a cladding region with the resin. After the coated fiber is exposed in a hydrogen atmosphere in a predetermined pressurized state for a predetermined period of time, the resin is partially removed. An ultraviolet ray is irradiated on the predetermined area of the bared fiber from which the resin is removed, thereby forming a reflection grating in the core region. The method is also characterized in that the pressure of the hydrogen atmosphere is reduced from the pressurized state while adjusting the pressure reducing rate.