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US 2025/0066239 A1Published application
Optical fiber preform and method for producing optical fiber preform
AssigneeShin-Etsu Chemical Co., Ltd.
InventorYuhei URATA
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AssigneeShin-Etsu Chemical Co., Ltd.
InventorYuhei URATA
Estimating the term…
An optical fiber preform, when manufactured by manufacturing a core glass preform composed of a core portion and a part of a clad portion, and then providing a remaining part of the clad portion on outside of the core glass preform, is characterized in that, in the core glass preform, a radial position where a relative refractive index difference has a value which is 0.45 times the relative refractive index difference at a core center is defined as a core radial position, then there is, in a range of 5% inside the core radial position, a location where the relative refractive index difference exhibits a locally high local maximum value ΔM and a location where the relative refractive index difference exhibits a locally low local minimum value Δm, and a value of ΔM−Δm does not exceed 0.04%.
An optical fiber preform, when manufactured by manufacturing a core glass preform composed of a core portion and a part of a clad portion, and then providing a remaining part of the clad portion on outside of the core glass preform, characterized in that, in the core glass preform, a radial position where a relative refractive index difference has a value which is 0.45 times the relative refractive index difference at a core center is defined as a core radial position, then there is, in a range of 5% inside the core radial position, a location where the relative refractive index difference exhibits a locally high local maximum value ΔM and a location where the relative refractive index difference exhibits a locally low local minimum value Δm and a value of ΔM−Δm which does not exceed 0.04%.
A manufacturing method for an optical fiber preform by manufacturing a core glass preform composed of a core portion and a part of a clad portion, and then providing a remaining part of the clad portion on outside of the core glass preform, characterized in that, in the core glass preform, a radial position where a relative refractive index difference has a value which is 0.45 times the relative refractive index difference at a core center is defined as a core radial position, then there is, in a range of 5% inside the core radial position, a location where the relative refractive index difference exhibits a locally high local maximum value ΔM and a location where the relative refractive index difference exhibits a locally low local minimum value Δm, and the remaining part of the clad portion is provided on outside of the core glass preform having a value of ΔM−Δm which does not exceed 0.04%.
Dependencies are inferred from the claim text.