122results about "Optical fibre with desired dispersion" patented technology

Disclosed is an improved, single-mode optical fiber possessing a novel coating system. When combined with a bend-insensitive glass fiber, the novel coating system according to the present invention yields an optical fiber having exceptionally low losses.The coating system features (i) a softer primary coating with excellent low-temperature characteristics to protect against microbending in any environment and in the toughest physical situations and, optionally, (ii) a colored secondary coating possessing enhanced color strength and vividness. The secondary coating provides improved ribbon characteristics for structures that are robust, yet easily entered (i.e., separated and stripped).The optional dual coating is specifically balanced for superior heat stripping in fiber ribbons, with virtually no residue left behind on the glass. This facilitates fast splicing and terminations. The improved coating system provides optical fibers that offer significant advantages for deployment in most, if not all, fiber-to-the-premises (FTTx) systems.

Disclosed is an improved optical fiber that employs a novel coating system. When combined with a bend-insensitive glass fiber, the novel coating system according to the present invention yields an optical fiber having exceptionally low losses. The coating system features (i) a softer primary coating with excellent low-temperature characteristics to protect against microbending in any environment and in the toughest physical situations and, optionally, (ii) a colored secondary coating possessing enhanced color strength and vividness. The improved coating system provides optical fibers that are useful in relatively thin-walled, low-modulus buffer tubes (i.e., “flextubes”) that can be readily accessed without special tools.

Disclosed is an improved optical fiber that employs a novel coating system. When combined with a bend-insensitive glass fiber, the novel coating system according to the present invention yields an optical fiber having exceptionally low losses.The coating system features (i) a softer primary coating with excellent low-temperature characteristics to protect against microbending in any environment and in the toughest physical situations and, optionally, (ii) a colored secondary coating possessing enhanced color strength and vividness.The improved coating system provides optical fibers that are useful in buffer tubes and cables having relatively high filling coefficients and fiber counts.

Disclosed is an improved, single-mode optical fiber possessing a novel coating system. When combined with a bend-insensitive glass fiber, the novel coating system according to the present invention yields an optical fiber having exceptionally low losses.The coating system features (i) a softer primary coating with excellent low-temperature characteristics to protect against microbending in any environment and in the toughest physical situations and, optionally, (ii) a colored secondary coating possessing enhanced color strength and vividness. The secondary coating provides improved ribbon characteristics for structures that are robust, yet easily entered (i.e., separated and stripped).The optional dual coating is specifically balanced for superior heat stripping in fiber ribbons, with virtually no residue left behind on the glass. This facilitates fast splicing and terminations. The improved coating system provides optical fibers that offer significant advantages for deployment in most, if not all, fiber-to-the-premises (FTTx) systems.

Disclosed is an improved optical fiber that employs a novel coating system. When combined with a bend-insensitive glass fiber, the novel coating system according to the present invention yields an optical fiber having exceptionally low losses.The coating system features (i) a softer primary coating with excellent low-temperature characteristics to protect against microbending in any environment and in the toughest physical situations and, optionally, (ii) a colored secondary coating possessing enhanced color strength and vividness.The improved coating system provides optical fibers that are useful in all-dielectric self-supporting (ADSS) cables.

The invention is directed to a dispersion-compensating optical fiber which can compensate for the chromatic dispersion and dispersion slope of a non-zero dispersion-shifted optical fiber by a short length. The dispersion-shifted optical fiber constitutes an optical transmission line together with a dispersion-compensating optical fiber fusion-spliced thereto. The dispersion-compensating optical fiber has, at a wavelength of 1550 nm, a chromatic dispersion DDCF of -40 ps / nm / km or less and a ratio (DDCF / SDCF) of dispersion slope SDCF to the chromatic dispersion DDCF of 0.005 / nm or more.

A high performance dispersion compensating optical fiber is provided. In one embodiment, the optical fiber includes a core layer and a cladding layer surrounding the core layer. The core layer includes five core sublayers wherein the □% of the first core sublayer is positive, and the □% of at least one of the other core sublayers is negative, the radius ranges of the respective core sublayers beginning outwardly from the first core sublayer are 0.6 to 0.8 μm, 1.0 to 1.2 μm, 1.6 to 2.0 μm, 5.0 to 6.0 μm, and 7.0 to 8.0 μm, respectively; the ranges of □% of the respective sublayers beginning outwardly from the first core sublayer are about 1.8 to 2.1%, 1.2 to 1.4%, 0.6 to 1%, −0.4 to −0.6% and 0.2 to 0.4%, and the cladding layer is a pure Silicon Dioxide glass layer.

Disclosed is an optical transmission system and module which includes a negative dispersion, dispersion compensating optical fiber coupled to a micro-structured optical fiber (such as band gap fiber, photonic crystal fiber or holey fiber) for compensating for the accumulated dispersion in a transmission fiber. The optical transmission system and module in accordance with the invention provides substantially equal compensation of total dispersion over an operating wavelength band, reduced overall system length, and lower insertion loss.

An apparatus for transporting an optical signal is provided. The apparatus includes sections of optical fiber span with at least one section negative dispersion, negative slope fiber positioned at a distance from the output. A pump light emitting device optically coupled to the optical fiber span near the output is provided for generating an amplification signal.

In order to provide a dispersion-compensating optical fiber able to be applied over a broad wavelength band, having a large effective area, and as a result, suppressing the occurrence of non-linear effects, the present invention comprises a dispersion-compensating optical fiber that compensates chromatic dispersion of a 1.3 mum single-mode optical fiber over the entire wavelength range of 1.53-1.63 mum characterized in that, chromatic dispersion at a wavelength of 1.55 mum is -50 ps / nm / km or less, the dispersion slope is negative over the entire wavelength range of 1.53-1.63 mum, a cutoff wavelength is provided at which there is substantially single-mode propagation, bending loss is 30 dB / m or less, effective area is 20 mum<2 >or more, and the absolute value of chromatic dispersion during compensation of the chromatic dispersion of a 1.3 mum single-mode optical fiber serving as the target of compensation is 0.5 ps / nm / km or less.

An optical fiber capable of compensating in the L-band both the chromatic dispersion and dispersion slope of a positive-dispersion optical fiber, an optical transmission line incorporating the optical fiber, and an optical communications system incorporating the optical transmission line. An optical communications system 1 comprises an optical transmission line 10, an optical transmitter 20, and an optical receiver 30. The optical transmission line 10 comprises an optical fiber 11 and an optical fiber 12 that are mutually fusion-spliced. The optical fiber 12 has at a wavelength of 1,590 nm a chromatic dispersion, D2, and a dispersion slope, S2, that satisfy the formulae −200 ps / nm / km≦D2≦−50 ps / nm / km, and 0.009 / nm≦S2 / D2.

In an optical fiber including a core region and cladding regions of not less than three layers which surrounds the core region in order, each of said cladding regions has a mean refractive index different from those of the adjacents regions,at least one of the cladding regions has a lower mean refractive index than both adjacent regions, and at least one cladding region is provided with a plurality of sub medium regions each having a refractive index lower than a main medium constituting this cladding region.

The invention proposes providing an optical fiber transmission system with a dispersion compensating fiber 12l to 12n to compensate the chromatic dispersion and chromatic dispersion slope of the line fiber 6l to 6n; the dispersion compensating fiber satisfies the following criteria:where C, C' et C'' are the chromatic dispersion, the chromatic dispersion slope and the first derivative of the chromatic dispersion slope of the dispersion compensating fiber, Cg and C'g are the chromatic dispersion and the chromatic dispersion slope of the line fiber, Ccum is the upper limit of the modulus of the cumulative chromatic dispersion in the transmission system, Lg is the length of a line fiber section, and DELTAlambd is half the bandwidth of the transmission system.The invention also proposes optical fibers verifying the above criteria and suitable for compensating the chromatic dispersion of step index or dispersion shifted line fiber.The proposed criteria compensate chromatic dispersion and chromatic dispersion slope in wideband transmission systems, e.g. in C band and L band transmission systems, for wavelengths from 1530 to 1620 nm.

A dispersion compensating fiber, which has a negative dispersion slope with a large absolute value while maintaining the absolute value of the chromatic dispersion, and which has sufficient dispersion slope compensation properties even for the non-zero dispersion shifted optical fiber requiring a large RDS for dispersion compensation. In this dispersion compensating fiber, the radius of a ring core region (3) is set in a range from 6.7 mu m to 10.7 mu m, the radius ratio of a depressed core region (2) relative to a central core region (1) is set in a range from 2.0 to 3.0, and the radius ratio of the ring core region (3) relative to the depressed core region (2) is set in a range from 1.3 to 2.0, the relative refractive index difference of the central core region (1) relative to the cladding (4) is set in a range from +1.00% to +1.80%, the relative refractive index difference of the depressed core region (2) relative to the cladding (4) is set in a range from -1.20% to -1.50%, and the relative refractive index difference of the ring core region (3) relative to the cladding (4) is set in a range from +0.20% to +0.50%.