An optical fiber containing alkali metal elements or the like in which Rayleigh scattering loss can be reduced is provided. An optical fiber includes a core composed of silica glass and a cladding which surrounds the core, has a refractive index lower than a refractive index of the core, and is composed of silica glass containing fluorine. The core contains a first group of dopants and a second group of dopants having a diffusion coefficient lower than a diffusion coefficient of the first group of dopants. The difference between the maximum value and the minimum value of residual stress in the optical fiber is 150 MPa or less.

Disclosed are biodegradable glass substrates that are useful as functional elements of solid-state devices. In particular, biodegradable glass substrates having a rapidly degradable glass and a slowly degradable glass provide a structural platform that completely dissolves following a desired operational lifetime of devices such as implanted electronic devices, implanted sensor devices, and optical fibers.

An optical glass has a refractive index n.sub.d of more than 2.10 and includes at least TiO.sub.2, NbO.sub.2.5, LaO.sub.1.5, SiO.sub.2, and B.sub.2O.sub.3. The glass has the following features: a cation parameter K of 1.8<K≤2.8, wherein K=(Ti-eq.+SiO.sub.2+(BO.sub.1.5)/2)/(La-eq.), the molar fractions of Ti-eq., SiO.sub.2, BO.sub.1.5 and La-eq. in the cation parameter K being in cat %; a sum total of glass components SiO.sub.2 and B.sub.2O.sub.3 of 8.0 mol %≤(SiO.sub.2+B.sub.2O.sub.3)≤20.0 mol %, the proportion of B.sub.2O.sub.3 being >0 mol % and the proportion of SiO.sub.2>0 mol %; and a temperature T.sub.max≤1330° C.

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.

Provided is an optical fiber glass preform in which a starting rod and a dummy glass are hardly separated from each other, and a method for manufacturing the glass preform. In the optical fiber glass preform, the dummy glass is fitted into one end of the starting rod, and a part of the dummy glass and the starting rod are surrounded by a clad glass. In the manufacturing method, at the time of connecting the starting rod and the dummy glass, a shape is adjusted in such a manner that an iron is brought into contact with a connection portion and is moved from a starting rod side toward a dummy glass side with appliance of a load.

An optical fiber having an axial direction and a cross section perpendicular to the axial direction, and a method and preform for producing such an optical fiber. The optical fiber is adapted to guide light at a wavelength λ, and includes a core region, an inner cladding region surrounding said core region, and at least one of a first type of feature including a void and a surrounding first silica material. The core, the inner cladding region and the first type of feature extends along said axial direction over at least a part of the length of the optical fiber. The first silica material has a first chlorine concentration of about 300 ppm or less.

Disclosed are methods for formation of a fiber and fibers that can be formed according to the methods. Formation methods incorporate a “molten core flux method” whereby a solid primary core material is combined with a solid secondary flux material in a multi-phase preform core. In some embodiments, the multi-phase preform core has a liquidus temperature that is reduced relative to the melting temperature of at least the primary core material. A homogeneous liquid melt of the preform core can exhibit a sufficiently low vapor pressure such that a fiber preform incorporating the materials in the core can be thermally drawn. Upon cooling and solidification of the homogeneous core melt, separation of the core components can occur via recrystallization, with one phase being that of the desired primary core material. Methods can be particularly beneficial for forming fibers incorporating high vapor pressure semiconductor materials, e.g., ZnSe or GaAs, in the fiber core.

A method for adjusting an etchability of a first borosilicate glass by heating the first borosilicate glass; combining the first borosilicate glass with a second borosilicate glass to form a composite; and etching the composite with an etchant. A material having a protrusive phase and a recessive phase, where the protrusive phase protrudes from the recessive phase to form a plurality of nanoscale surface features, and where the protrusive phase and the recessive phase have the same composition.

In an example implementation, a sintering system includes optical fiber installed into a sintering furnace. A support structure inside the furnace is to support a token green object in a predetermined position and to hold a distal end of the fiber adjacent to the predetermined position. A light source is operably engaged at a proximal end of the fiber to transmit light through the fiber into the furnace. A light detector is operably engaged at the proximal end of the fiber to receive reflected light through the fiber that scatters off a surface of the token green object.

The present application provides a method for recovering and reusing quartz powder waste in an out-of-tube deposition process. The quartz powder recovered by this method meets the optical performance requirements for the preparation of an optical fiber preform rod having a functional cladding, reduces the production cost, and solves the problem of environmental pollution. Also, the present invention further provides a method for preparing an optical fiber preform rod by using the recovered quartz powder. The method reduces and simplifies the difficulty in the manufacturing of a core rod of a preform rod, and simplifies the difficulty in the manufacturing of some preform rods of special structures.