Abstract: There is provided an apparatus and method for fabricating a holey optical fiber. An optical fiber with air holes of a predetermined size and shape along the length of the optical fiber is drawn by supplying nitrogen gas into air holes through one end of a holey optical fiber preform while heating the other end of the preform.

Abstract: An optical fiber for maximizing residual mechanical stress and an optical fiber grating fabricating method using the optical fiber are provided. The optical fiber includes a core formed of silica, for propagating light, and a cladding formed of boron-doped silica, surrounding the core. Alternatively, the optical fiber includes a core formed of phosphorous-doped silica and a cladding formed of silica, surrounding the core.

Abstract: Disclosed is an apparatus for measuring a residual stress and a photoelastic effect of an optical fiber, which includes: a light source; a rotary type optical diffuser distanced from the light source in a predetermined distance for suppressing the spatial coherence of a light radiated in the light source; an optical condenser for condensing the radiated light passed through the optical diffuser into a spot where the optical fiber is located; a polarizer for polarizing the light passed through the optical condenser into a 45° linear polarized light from an axis of the optical fiber; a polarization analyzer, installed at 90° angle with respect to the polariscope and attached closely with the optical fiber, to prevent the penetration by the background image of the optical fiber; an optical fiber strain unit including a strain sensor for straining the optical fiber on the polarization analyzer toward a longitudinal direction and measuring the strain on the optical fiber; an object lens for magnifying the

Abstract: Disclosed is a photonic crystal-fiber coupler that can distribute light while maintaining the inherent optical properties of photonic crystal fibers. The inventive photonic crystal-fiber coupler comprises at least two photonic crystal fibers and at least one coupling region longitudinally formed along the part of each photonic crystal fiber. Each photonic crystal fiber has a core portion and a cladding portion and includes a plurality of longitudinal holes formed in such a manner to surround the core portion.

Abstract: There is provided an apparatus and method for fabricating a holey optical fiber. An optical fiber with air holes of a predetermined size and shape along the length of the optical fiber is drawn by supplying nitrogen gas into air holes through one end of a holey optical fiber preform while heating the other end of the preform.

Abstract: There is provided an apparatus and method for fabricating a holey optical fiber. An optical fiber with air holes of a predetermined size and shape along the length of the optical fiber is drawn by supplying nitrogen gas into air holes through one end of a holey optical fiber preform while heating the other end of the preform.

Abstract: An apparatus and method for measuring residual stress and photoelastic effect of an optical fiber is disclosed.

Abstract: Disclosed is an apparatus for measuring a residual stress and a photoelastic effect of an optical fiber, which includes: a light source; a rotary type optical diffuser distanced from the light source in a predetermined distance for suppressing the spatial coherence of a light radiated in the light source; an optical condenser for condensing the radiated light passed through the optical diffuser into a spot where the optical fiber is located; a polarizer for polarizing the light passed through the optical condenser into a 45° linear polarized light from an axis of the optical fiber; a polarization analyzer, installed at 90° angle with respect to the polariscope and attached closely with the optical fiber, to prevent the penetration by the background image of the optical fiber; an optical fiber strain unit including a strain sensor for straining the optical fiber on the polarization analyzer toward a longitudinal direction and measuring the strain on the optical fiber; an object lens for magnifying the

Abstract: Disclosed is an apparatus for measuring a residual stress and a photoelastic effect of an optical fiber, which includes: a light source; a rotary type optical diffuser distanced from the light source in a predetermined distance for suppressing the spatial coherence of a light radiated in the light source; an optical condenser for condensing the radiated light passed through the optical diffuser into a spot where the optical fiber is located; a polarizer for polarizing the light passed through the optical condenser into a 45° linear polarized light from an axis of the optical fiber; a polarization analyzer, installed at 90° angle with respect to the polariscope and attached closely with the optical fiber, to prevent the penetration by the background image of the optical fiber; an optical fiber strain unit including a strain sensor for straining the optical fiber on the polarization analyzer toward a longitudinal direction and measuring the strain on the optical fiber; an object lens for magnifying the

Abstract: A dispersive optical fiber having variable core-cladding refractive index differences depending on wavelength is provided. The dispersive optical fiber includes a core made of silica doped with a first dispersive material, and a cladding made of silica doped with a second dispersive material, wherein the refractive indices of the first and the second dispersive materials cross each other at a predetermined cross wavelength. The first and second dispersive materials include boron and fluorine. The dispersive optical fiber is attained by doping each dispersive material into the core and the cladding, respectively, thereby minimizing transmission loss, and is capable of being coupled to general optical fibers.

Abstract: An alloy-coated optical fiber and a fabricating method. In the alloy-coated optical fiber, a core is formed of a light transmitting material, a clad surrounds the outer circumferential surface of the core, and an indium-tin-silver coating layer is formed around the outer circumferential surface of the clad while maintaining the alloy temperature at substantially 5° C. above the melting point of this indium-silver alloy coat.

Abstract: An optical fiber for maximizing residual mechanical stress and an optical fiber grating fabricating method using the optical fiber are provided. The optical fiber includes a core formed of silica, for propagating light, and a cladding formed of boron-doped silica, surrounding the core. Alternatively, the optical fiber includes a core formed of phosphorous-doped silica and a cladding formed of silica, surrounding the core.

Abstract: An optical fiber for maximizing residual mechanical stress and an optical fiber grating fabricating method using the optical fiber are provided. The optical fiber includes a core formed of silica, for propagating light, and a cladding formed of boron-doped silica, surrounding the core. Alternatively, the optical fiber includes a core formed of phosphorous-doped silica and a cladding formed of silica, surrounding the core.

Abstract: There is provided a dispersion-managed fiber preform and a fabricating method thereof preform by modified chemical vapor deposition (MCVD). A core and a clad having the refractive index distribution of an optical fiber with a positive dispersion value are uniformly deposited in a glass tube. The preform with the positive dispersion value is heated at every predetermined period with a torch and the heated preform portions are etched to have a negative dispersion value. Then, the preform alternately having positions with the positive dispersion value and positions with the negative dispersion value along the length direction is collapsed.

Abstract: An apparatus and method for measuring residual stress and photoelastic effect of an optical fiber is disclosed.

Abstract: The present invention relates to a method of metal coating for an optical fiber grating with a long period. More specifically, the present invention relates to a method of using silver (Ag) as a coating material for an optical fiber through ascertaining its characteristics after silver is coated on the surface of the optical fiber using a silver mirror reaction.

Abstract: An erbium-doped optical fiber (EDF) and a fabricating method thereof The erbium-doped optical fiber has a core formed by substantially doping silica with erbium and having gratings formed therein at a predetermined period, for propagating light therethrough, and a cladding surrounding the core and having a lower refractive index than the core. Since the erbium-doped optical fiber acts as a gain flattening filter, an erbium-doped fiber amplifier formed out of the erbium-doped optical fiber obviates the need of splicing an erbium-doped optical fiber with a gain flattening filter.

Abstract: There is provided a device and method for forming optical fiber anti-symmetric long period gratings by microbending. In the optical fiber grating forming device, a laser system emits a CO2 laser beam, a lens focuses the CO2 laser beam on an optical fiber in a predetermined width, an optical fiber support fixes both ends of the optical fiber and imparts tensile strain to the optical fiber, and a controller controls the intensity of the CO2 laser beam, the focusing distance of the lens, and the tensile force applied by the optical fiber support.

Abstract: The present invention relates generally to an image tracking device in an optical communication system, and in particular, to a device and method for measuring the transverse characteristics, including the refractive index or residual stress of an optical fiber or a fiber preform.

Abstract: An image-tracking device and method for transverse measurement of an optical fiber are provided. The image tracking device includes a linear object, a light source for emitting light onto the light object; a first convex lens for projecting the light received via the linear object onto the outer circumferential surface of the optical fiber and forming a primary image of the linear object penetrating the optical fiber; a second convex lens for converging the light received via the optical fiber and forming a secondary image of the linear object; an image sensor for detecting the secondary image; and, a controller for calculating the distance between the primary image and the center of the optical fiber from the distortion degree of the detected secondary image.