Dispersion flattened fiber with high negative dispersion and method for the manufacture thereof
AssigneeKorea Telecom
InventorsJeong U. Jeon, Young Tark Lee
Life of this patent
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Abstract
The invention relates to a dispersion flattened fiber (DFF) with high negative dispersion and a manufacturing method thereof. The dispersion flattened fiber comprises a central core; ring-type cores and low refractive regions alternately formed outside the central core; a cladding surrounding outside the ring-type cores and low refractive regions; and a coating outside the cladding. Since the dispersion flattened fiber has the dispersion of −20 to −60, it has a wide range of application and can be used for various purposes in the field of optical telecommunication.
Claims12
A manufacturing method of a dispersion flattened fiber with high negative dispersion ranging from about −20 ps/nm/km to about −60 ps/nm/km, comprising the steps of:
- (a) preparing a silica tube;
- (b) cleaning the silica tube;
- (c) forming a cladding on an inner peripheral surface of the silica tube;
- (d) forming a first ring-type core on an inner peripheral surface of the cladding;
- (e) forming a first low refractive region on an inner peripheral surface of the first ring-type core, wherein the refractive index of the first low refractive region is lower than that of the cladding;
- (f) forming a second ring-type core on an inner peripheral surface of the first low refractive region;
- (g) forming a second low refractive region on an inner peripheral surface of the second ring-type core, wherein the refractive index of the second low refractive region is lower than that of the cladding;
- (h) forming the a central core on an inner peripheral surface of the second low refractive region;
- (i) heating the silica tube, thereby forming a preform of the dispersion flattened fiber;
- and
- (j) extracting the dispersion flattened fiber from the perform.
Dependencies are inferred from the claim text.