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 wafer including a glass substrate is provided. The glass substrate includes a first surface defining a plane and including a surface roughness R.sub.a of approximately 0.3 nm in an outer via region and a second surface. The glass substrate defines a plurality of vias extending from the first surface. The plurality of vias each include an entrance defined by the first surface.

Synthetic quartz glass substrates are prepared by furnishing a synthetic quartz glass block, coating two opposed surfaces of the glass block with a liquid having a transmittance of at least 99.0%/mm at a birefringence measuring wavelength, measuring a birefringence of the glass block by directing light thereacross, determining a slice thickness on the basis of the birefringence measurement and the dimensions of the substrate, and slicing the glass block at the determined slice thickness.

An article including a glass having that includes SiO.sub.2, Al.sub.2O.sub.3, and B.sub.2O.sub.3 and least one of Li.sub.2O, Na.sub.2O, K.sub.2O, MgO, CaO, SrO, BaO, SnO.sub.2, ZnO, La.sub.2O.sub.3, F, and Fe.sub.2O.sub.3, wherein the glass includes a dielectric constant of about 10 or less and/or a loss tangent of about 0.01 or less, both as measured with signals at 10 GHz.

The present invention is an annealed quartz glass cloth that has an SiO.sub.2 content of 99.5 mass % or more, a dielectric loss tangent of less than 0.0010 at 10 GHz, and a tensile strength of 1.0 N/25 mm or more per cloth weight (g/m.sup.2). This provides an annealed quartz glass cloth that has a low dielectric loss tangent and that is also excellent in tensile strength; and a method for manufacturing an annealed quartz glass cloth by which strength recovers after a high-temperature heat treatment.

An optical fiber according to an embodiment includes a core and a cladding. The average value n1_ave of the refractive index of the core, the minimum value nc_min of the refractive index of the cladding, and the refractive index n0 of pure silica glass satisfy relationships of n1_ave>nc_min and nc_min<n0. The cladding contains fluorine. The fluorine concentration in the cladding is adjusted to be minimum in the outermost portion of the cladding including the outer peripheral surface of the cladding.

A transparent β-quartz glass ceramic is provided. The glass ceramic includes a primary crystal phase including a β-quartz solid solution, a secondary crystal phase including tetragonal ZrO.sub.2, and a lithium aluminosilicate amorphous phase. The glass ceramic may be ion exchanged utilizing molten nitrate salt baths. Methods for producing the glass ceramic are also provided.

A method of manufacturing a scintillator material includes providing a substrate made of a quartz glass and having a recess formed therein; filling the recess with a raw material powder obtained by mixing an iodide raw material and SiO.sub.2 fine particles; after filling the recess, disposing a lid on the substrate to cover the recess; and after disposing the lid, heating the substrate, thereby forming a nanocomposite layer in which an iodide phosphor is introduced into a cristobalite structure.

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.

A resin composition for coating an optical fiber comprises: a base resin containing a photopolymerizable compound and a photopolymerization initiator; and hydrophobic inorganic oxide particles, wherein the photopolymerizable compound comprises urethane (meth)acrylate and aliphatic epoxy (meth)acrylate, and the content of the aliphatic epoxy (meth)acrylate is 1.0% by mass or more and 45% by mass or less based on the total amount of the photopolymerizable compound.