Abstract:
The present invention embraces an amplifying optical fiber having a central core adapted to convey and amplify an optical signal and a cladding that surrounds the central core to confine the optical signal conveyed in the central core. The central core is formed of a core matrix in which nanoparticles are present. The nanoparticles themselves include a nanoparticle matrix and rare-earth-dopant elements. The core matrix may also include one or more additional dopants (i.e., in addition to nanoparticles). The amplifying optical fiber possesses a small numerical aperture and is suitable for use in high-pump-power applications without a degraded gain shape.
Abstract:
An apparatus and method for compensating for mode-profile distortions caused by bending optical fibers having large mode areas. In various embodiments, the invention micro-structures the index of refraction in the core and surrounding areas of the inner cladding from the inner bend radius to the outer bend radius in a manner that compensates for the index changes that are otherwise induced in the index profile by the geometry and/or stresses to the fiber caused by the bending. Some embodiments of an apparatus and method include a fiber having a plurality of substantially parallel cores, the fiber including a straight section and a curved section; guiding signal light primarily in a second core in the straight section; guiding the signal light from the second core into a first core between the straight section and the curved section; and guiding the signal light primarily in the first core in the curved section.
Abstract:
A glass preform manufacturing method includes: generating glass fine particles by hydrolyzing a source gas in an oxyhydrogen flame; depositing the generated glass fine particles to form a torous glass preform; immersing the porous glass preform in an additive solution including an additive solvent in which a compound containing a desired additive is dissolved to impregnate the additive solution into the porous glass preform; first replacing of replacing the additive solvent remaining in the porous glass preform with the replacement solvent by immersing the porous glass preform in which the additive solution remains in a replacement solvent in which a solubility of the additive is lower than that in the additive solvent and having miscibility with the additive solvent; drying the porous glass preform after the first replacing; and sintering the dried porous glass preform to transparently vitrify the dried porous glass preform.
Abstract:
A rare earth-doped core optical fiber of the present invention includes a core comprising a silica glass containing at least aluminum and ytterbium, and a clad provided around the core and comprising a silica glass having a lower refraction index than that of the core, wherein the core has an aluminum concentration of 2% by mass or more, and ytterbium is doped into the core at such a concentration that the absorption band which appears around a wavelength of 976 nm in the absorption band by ytterbium contained in the core shows a peak absorption coefficient of 800 dB/m or less.
Abstract:
As a jig material to use under plasma reaction for producing semiconductors, the present invention provides a quartz glass having resistance against plasma corrosion, particularly corrosion resistance against fluorine-based plasma gases, and which is usable without causing anomalies to silicon wafers; the present invention furthermore provides a quartz glass jig, and a method for producing the same. A quartz glass containing 0.1 to 20 wt % in total of two or more types of metallic elements, said metallic elements comprising at least one type of metallic element selected from Group 3B of the periodic table as a first metallic element and at least one type of metallic element selected from the group consisting of Mg, Ca, Sr, Ba, Sc, Y, Ti, Zr, Hf, lanthanoids, and actinoids as a second metallic element, provided that the maximum concentration of each of the second metallic elements is 1.0 wt % or less.
Abstract:
A first step, in which P2O5-containing glass is deposited inside a silica glass pipe, and a second step, in which a Cl2-containing gas is introduced into the pipe and the P2O5-containing glass is dehydrated by heating the pipe, are repeated alternately. A third step, in which glass that does not contain P2O5 is deposited on the inside of the silica glass pipe, may further be provided such that the first step, the second step, and the third step are repeatedly performed in this order. A rare-earth-doped optical fiber, which has a attenuation of 15 dB/km or less at a wavelength of 1200 nm, comprises a core region and a cladding region enclosing the core region, wherein the core region includes phosphorus of 3 wt % or more, aluminum of 0.3 wt % or more, a rare-earth element of 500 wtppm or more, and chlorine of 0.03 wt % or more, and the cladding region has a refractive index that is lower than the refractive index of the core region.
Abstract:
The glass fiber for an optical amplifier has a matrix glass core, a first glass cladding, and a second glass cladding. The matrix glass core has a composition, in mol %, of Bi2O3, 30-60; SiO2, 0.5-40; B2O3, 0.5-40; Al2O3, 0-30; Ga2O3, 0-20; Ge2O3, 0-25 ; La2O3, 0-15; Nb2O5, 0-10; SnO2, 0-30; alkali metal oxides, 0-40; and Er2O3, 0.05-8. The glass claddings have the same composition as the core, except that a transition metal compound is included as an absorbent. The refraction index of the matrix glass is > about 1.85, the refraction index of the first glass cladding is less than that of the core, and the refraction index of the second glass cladding is higher than that of the first.
Abstract:
As a jig material to use under plasma reaction for producing semiconductors, the present invention provides a quartz glass having resistance against plasma corrosion, particularly corrosion resistance against fluorine-based plasma gases, and which is usable without causing anomalies to silicon wafers; the present invention furthermore provides a quartz glass jig, and a method for producing the same. A quartz glass containing 0.1 to 20 wt % in total of two or more types of metallic elements, said metallic elements comprising at least one type of metallic element selected from Group 3B of the periodic table as a first metallic element and at least one type of metallic element selected from the group consisting of Mg, Ca, Sr, Ba, Sc, Y, Ti, Zr, Hf, lanthanoids, and actinoids as a second metallic element, provided that the maximum concentration of each of the second metallic elements is 1.0 wt % or less.
Abstract:
The invention relates to a method for doping material, the method being characterized by depositing at least one dopant deposition layer or a part thereof on the surface of the material and/or on a surface of a part or parts thereof with the atom layer deposition (ALD) method, and further processing the material coated with a dopant in such a manner that the original structure of the dopant layer is changed to obtain new properties for the doped material. The material to be doped is preferably glass, ceramic, polymer, metal, or a composite material made thereof, and the further processing of the material coated with the dopant is a mechanical, chemical, radiation, or heat treatment, whereby the aim is to change the refraction index, absorbing power, electrical and/or heat conductivity, colour, or mechanical or chemical durability of the doped material.
Abstract:
A preform for a low loss fiber optic cable and method and apparatus for fabricating such a preform is provided. The method includes providing AlCl3 and CVD precursors and locally doping CaCl3. Alkali and/or alkaline earth fluxing agents can be introduced. The alkali and/or alkaline earths are doped along with the aluminum into the silica glass core.