Abstract:
A blank made of titanium-doped silica glass for a mirror substrate for use in EUV lithography is provided. The blank includes a surface portion to be provided with a reflective film and having an optically used area (CA) over which a coefficient of thermal expansion (CTE) has a two-dimensional inhomogeneity (dCTE) distribution profile averaged over a thickness of the blank. A maximum inhomogeneity (dCTEmax) of less than 5 ppb/K is defined as a difference between a CTE maximum value and a CTE minimum value. The dCTEmax is at least 0.5 ppb/K. The CA forms a non-circular area having a centroid. The dCTE distribution profile is not rotation-symmetrical and is defined over the CA, such that straight profile sections normalized to a unit length and extending through the centroid of the area yield a dCTE family of curves forming a curve band with a bandwidth of less than 0.5×dCTEmax.
Abstract:
A method for forming an optical fiber preform and fibers drawn from the preform. The method includes forming a soot cladding monolith, inserting a consolidated core cane into the internal cavity, and processing the resulting core-cladding assembly to form a preform. Processing may include exposing the core-cladding assembly to a drying agent and/or dopant precursor, and sintering the core-cladding assembly in the presence of a reducing agent to densify the soot cladding monolith onto the core cane to form a preform. The preform features low hydroxyl content and low sensitivity to hydrogen. Fibers drawn from the preform exhibit low attenuation losses from absorption by the broad band centered near 1380 nm.
Abstract:
A manufacturing method according to an embodiment of the invention includes a step of calculating Pj0.1 satisfying (62.6×JOH+1175)×Pj=0.1, where Pj is an optical power ratio at the wavelength 1383 nm of a portion corresponding to a cladding material of an MCF after drawn, and an outer diameter ratio Pcc0.1 of core portions to core rods to obtain Pj0.1. The core rods have an outer diameter 2R0.1 satisfying the condition that a ratio Pcc is not less than the ratio Pcc0.1, and the cladding material has holes formed in a diameter larger by C (not less than 0.15 mm and not more than 1.5 mm) than the outer diameter of the core rods.
Abstract:
Methods for producing an optical fiber by elongating a silica glass blank or a coaxial group of silica glass components, on the basis of which a fiber is obtained that comprises a core zone, an inner jacket zone enclosing the core zone and a ring zone surrounding the inner jacket zone, are known. In order to provide, proceeding from this, a method, a tubular semi-finished product and a group of coaxial components for the cost-effective production of an optical fiber, which is characterized by a high quality of the boundary between the core and jacket and by low bending sensitivity, according to the invention, the silica glass of the ring zone is provided in the form of a ring zone tube made of silica glass having a mean fluorine content of at least 6000 weight ppm and the tube has an inner tube surface and an outer tube surface, wherein via the wall of the ring zone tube, a radial fluorine concentration profile is adjusted which has an inner fluorine depletion layer with a layer thickness of at least 1 μm and no more than 10 μm, in which the fluorine content decreases toward the inner tube surface and is no more than 3000 weight ppm in a region close to the surface which has a thickness of 1 μm.
Abstract:
Disclosed is a method of producing a synthetic quartz glass for excimer laser by depositing on a target silica particulates obtained by subjecting a silica raw material to vapor-phase hydrolysis or oxidative decomposition in an oxyhydrogen flame in a vacuum sintering furnace to form a porous silica base material, vitrifying the porous silica base material, and subjecting the vitrified material to hot forming, an annealing treatment and a hydrogen doping treatment, wherein the vitrification of the porous silica base material includes: (a) a step of holding a vacuum pressure at or below 20.0 Pa in a temperature range from 400° C., inclusive, to 900° C., exclusive; (b) a step of holding a vacuum pressure at or below 10.0 Pa in a temperature range from 900° C., inclusive, to 1100° C., exclusive; and (c) a step of holding a vacuum pressure at or below 3.0 Pa in a temperature range from 1100° C. to a transparent-vitrification temperature.
Abstract:
The following method steps are known for producing cylindrical components from synthetic quartz glass containing fluorine: producing a SiO2 soot body, removing hydroxyl groups from the soot body, loading the soot body with fluorine, post-chlorinating the soot body loaded with fluorine, and vitrifying the soot body to form the cylindrical component. In order to achieve distributions in particular of fluorine that are especially reproducibly homogeneous axially and radially, according to the invention it is proposed that a concentration of hydroxyl groups in the range of 1 to 300 weight ppm is set in the soot body upon the drying and an average fluorine content of at least 1500 weight ppm is set upon the loading with fluorine, and that loading with chlorine occurs during the post-chlorination, which loading results in an average chlorine content of at least 50 weight ppm in the synthetic quartz glass after the vitrification, under the further stipulation that the weight ratio of the contents of fluorine and chlorine is less than 30.
Abstract:
Provided is an inexpensive low-loss optical fiber suitably used in an optical transmission network. An optical fiber includes a core, an optical cladding, and a jacket. The core has a relative refractive index difference between 0.2% and 0.32% and has a refractive index volume between 9%·μm2 and 18%·μm2. The jacket has a relative refractive index difference between 0.03% and 0.20%. Glass constituting the core has a fictive temperature between 1400° C. and 1560° C. Stress remaining in the core is compressive stress. A cutoff wavelength measured on a fiber having a length of 2 m is 1300 nm or more and a cutoff wavelength measured on a fiber having a length of 100 m is 1500 nm or less. An effective area at a wavelength of 1550 nm is 110 μm2 or more. A attenuation at a wavelength of 1550 nm is 0.19 dB/km or less.
Abstract:
A known refraction-sensitive optical fiber comprises a core zone with an index of refraction nK, a jacket zone surrounding the core zone, said jacket zone having an index of refraction nM, and an annular zone made of quartz glass doped with fluorine, said annular zone surrounding the jacket zone and having an index of refraction nF, where nF
Abstract:
A method of making a silica glass having a uniform fictive temperature. The glass article is heated at a target fictive temperature, or heated or cooled at a rate that is less than the rate of change of the fictive temperature, for a time that is sufficient to allow the fictive temperature of the glass to come within 3° C. of the target fictive temperature. The silica glass is then cooled from the target fictive temperature to a temperature below the strain point of the glass at a cooling rate that is greater than the relaxation rate of the glass at the target fictive temperature. The silica glass has a fictive temperature that varies by less than 3° C. after the annealing step. A silica glass made by the method is also described.
Abstract:
The present invention relates to a method for manufacturing a preform for optical fibers, wherein deposition of glass-forming compounds on the substrate takes place. The present invention furthermore relates to a method for manufacturing optical fibers, wherein one end of a solid preform is heated, after which an optical fiber is drawn from said heated end.