This coating condition detection method according to one embodiment uses a simple device structure to detect the coating condition of a resin layer of a coated fiber. Under the coating condition detection method, an imaging optical system including a reflection mirror having a guide hole through which the optical fiber passes is prepared, and the imaging optical system is disposed so as to cause an object plane conjugate with an imaging plane to intersect the optical fiber that has passed through the reflection mirror and forms an image of light released from the optical fiber on the imaging plane to detect intensity of light at each point on the imaging plane with the intensity of light associated with information on a corresponding position on the object plane.

This coating condition detection method according to one embodiment uses a simple device structure to detect the coating condition of a resin layer of a coated fiber. Under the coating condition detection method, an imaging optical system including a reflection mirror having a guide hole through which the optical fiber passes is prepared, and the imaging optical system is disposed so as to cause an object plane conjugate with an imaging plane to intersect the optical fiber that has passed through the reflection mirror and forms an image of light released from the optical fiber on the imaging plane to detect intensity of light at each point on the imaging plane with the intensity of light associated with information on a corresponding position on the object plane.

A light-diffusing optical element with efficient coupling to light sources with high numerical aperture. The light-diffusing optical element includes a higher index core surrounded by a lower index cladding. The cladding includes scattering centers that scatter evanescent light entering the cladding from the core. The scattered light exits the element to provide broad-area illumination along the element. Scattering centers include dopants, nanoparticles and/or internal voids. The core may also include scattering centers. The core is glass and the cladding may be glass or a polymer. The element features high numerical aperture and high scattering efficiency.

An eccentric state determining method which is performed by a controller and for determining a state of eccentricity of a coating of a glass fiber with respect to the glass fiber. The coating is formed around the glass fiber. The method includes acquiring measurement values for an outer diameter of the optical fiber at positions along a longitudinal direction of the optical fiber, calculating a standard deviation of the measurement values, and determining the state of the eccentricity based on the standard deviation.

An eccentric state determining method which is performed by a controller and for determining a state of eccentricity of a coating of a glass fiber with respect to the glass fiber. The coating is formed around the glass fiber. The method includes acquiring measurement values for an outer diameter of the optical fiber at positions along a longitudinal direction of the optical fiber, calculating a standard deviation of the measurement values, and determining the state of the eccentricity based on the standard deviation.

Described herein are coated optical fibers including an optical fiber portion, wherein the optical fiber portion includes a glass core and cladding section that is configured to possesses certain mode-field diameters and effective areas, and a coating portion including a primary and secondary coating, wherein the primary coating is the cured product of a composition that possesses specified liquid glass transition temperatures, such as below −82° C., and/or a viscosity ratios, such as between 25° C. and 85° C., of less than 13.9. Also described are radiation curable coating compositions possessing reduced thermal sensitivity, methods of coating such radiation curable coating compositions to form coated optical fibers, and optical fiber cables comprising the coated optical fibers and/or radiation curable coating compositions elsewhere described.

Described herein are coated optical fibers including an optical fiber portion, wherein the optical fiber portion includes a glass core and cladding section that is configured to possesses certain mode-field diameters and effective areas, and a coating portion including a primary and secondary coating, wherein the primary coating is the cured product of a composition that possesses specified liquid glass transition temperatures, such as below −82° C., and/or a viscosity ratios, such as between 25° C. and 85° C., of less than 13.9. Also described are radiation curable coating compositions possessing reduced thermal sensitivity, methods of coating such radiation curable coating compositions to form coated optical fibers, and optical fiber cables comprising the coated optical fibers and/or radiation curable coating compositions elsewhere described.

A method for manufacturing an optical fiber, the method including: a stripping step of partially stripping a coating layer of the optical fiber; a splicing step of fusion-splicing an exposed end surface of a glass fiber; and a recoating step of recoating a protective resin covering a stripped portion of the coating layer and an exposed portion of the glass fiber, in which the stripping step is a step of irradiating the coating layer with a laser light to strip the coating layer.

A system and method for treating the end of an optical fiber bundle to reduce light scattering/reflection is provided. After the end of the optical fiber bundle is formed, it has a raw end. A material is applied to the raw end to form a treated end that provides a substantially smoother surface then the raw cut end, which reduces the amount of light rays reflected from the end.

A system and method for treating the end of an optical fiber bundle to reduce light scattering/reflection is provided. After the end of the optical fiber bundle is formed, it has a raw end. A material is applied to the raw end to form a treated end that provides a substantially smoother surface then the raw cut end, which reduces the amount of light rays reflected from the end.