A Photonic Crystal Fiber (PCF) a method of its production and a supercontinuum light source comprising such PCF. The PCF has a longitudinal axis and includes a core extending along the length of said longitudinal axis and a cladding region surrounding the core. At least the cladding region includes a plurality of microstructures in the form of inclusions extending along the longitudinal axis of the PCF in at least a microstructured length section. In at least a degradation resistant length section of the microstructured length section the PCF includes hydrogen and/or deuterium. In at least the degradation resistant length section the PCF further includes a main coating surrounding the cladding region, which main coating is hermetic for the hydrogen and/or deuterium at a temperature below T.sub.h, wherein T.sub.h is at least about 50? C., preferably 50? C.<T.sub.h<250? C.

An optical sensor device includes an optical waveguide portion having a core, the core having a first refractive index, and a functional material layer coupled to the optical fiber portion, the functional material layer being made of a metal oxide material, the functional material layer being structured to have a second refractive index, the second refractive index being less than the first refractive index. The functional material layer may be a nanostructure material comprising the metal oxide material with a plurality of holes or voids formed therein such that the functional material layer is caused to have the second refractive index.

The invention relates to a method for producing an optical waveguide (1), the surface of which is at least partly coated with a coating material. The coating material contained in a target (4) is removed using laser radiation (6) of a processing laser or converted into another aggregate state. The coating material is then deposited on the surface of the waveguide (1) and forms a coating thereon, said coating modifying the light guidance. It is the object of the present invention to provide an improved method for producing optical waveguides, in which guidance of undesired electromagnetic radiation and/or guidance of radiation in undesired areas of the waveguide is avoided. To this effect, the present invention proposes that the laser radiation (7) reflected from the target (4) or transmitted through the target heats-up the waveguide (1), said laser radiation (6) being polarized and impinging the target (4) at a specified angle () between 10 and 80 relative to the surface normal.

An optical fiber having a core comprising silica and greater than 1.5 wt % chlorine and less than 0.5 wt % F, said core having a refractive index .sub.1MAX, and a inner cladding region having refractive index .sub.2MIN surrounding the core, where .sub.1MAX>.sub.2MIN.

A Photonic Crystal Fiber (PCF) a method of its production and a supercontinuum light source comprising such PCF. The PCF has a longitudinal axis and includes a core extending along the length of said longitudinal axis and a cladding region surrounding the core. At least the cladding region includes a plurality of microstructures in the form of inclusions extending along the longitudinal axis of the PCF in at least a microstructured length section. In at least a degradation resistant length section of the microstructured length section the PCF includes hydrogen and/or deuterium. In at least the degradation resistant length section the PCF further includes a main coating surrounding the cladding region, which main coating is hermetic for the hydrogen and/or deuterium at a temperature below T.sub.h, wherein T.sub.h is at least about 50? C., preferably 50? C.<T.sub.h<250? C.

Disclosed are a method and a device for preparing a single-crystal cladding. The method may include preparing an amorphous material; melting the amorphous material to form an amorphous melt; submerging an optical fiber in the amorphous melt; forming an amorphous cladding around a periphery of the optical fiber; and obtaining the single-crystal cladding by performing a crystallization process on the amorphous cladding. The device may include an amorphous material preparation component configured to prepare an amorphous material; an amorphous cladding preparation component configured to melt the amorphous material to form an amorphous melt, submerge an optical fiber in the amorphous melt, and form an amorphous cladding around a periphery of the optical fiber based on the amorphous melt and the optical fiber; and a single-crystal cladding preparation assembly configured to perform a crystallization process on the amorphous cladding to obtain a single-crystal cladding.

The invention concerns a Photonic Crystal Fiber (PCF) a method of its production and a supercontinuum light source comprising such PCF. The PCF has a longitudinal axis and comprises a core extending along the length of said longitudinal axis and a cladding region surrounding the core. At least the cladding region comprises a plurality of microstructures in the form of inclusions extending along the longitudinal axis of the PCF in at least a microstructured length section. In at least a degradation resistant length section of the microstructured length section the PCF comprises hydrogen and/or deuterium. In at least the degradation resistant length section the PCF further comprises a main coating surrounding the cladding region, which main coating is hermetic for the hydrogen and/or deuterium at a temperature below Th, wherein Th is at least about 50? C., preferably 50? C.<Th<250? C.

A flame retardant optical fiber is provided. The flame retardant optical fiber includes a glass core, a cladding surrounding the glass core and a primary coating adhered to the cladding. The flame retardant optical fiber also includes a secondary coating surrounding the primary coating, wherein the secondary coating is formed from a coating composition that is substantially free of an oligomeric component and that comprises a flame retardant composition including a flame retardant material.

An all-glass cladding mode stripper comprises a plurality of high refractive index, small diameter glass beads disposed along an exposed portion of the inner cladding region of an optical fiber. The unwanted low NA signal light (as well as any other type of stray light) propagating within the cladding layer is removed by refracting into the adjacent beads, where this captured light then scatters away from the optical fiber.

An optical sensor device includes an optical waveguide portion having a core, the core having a first refractive index, and a functional material layer coupled to the optical fiber portion, the functional material layer being made of a metal oxide material, the functional material layer being structured to have a second refractive index, the second refractive index being less than the first refractive index. The functional material layer may be a nanostructure material comprising the metal oxide material with a plurality of holes or voids formed therein such that the functional material layer is caused to have the second refractive index.