Abstract: The field of the invention is that of optical fibers for use in wavelength division multiplex transmission networks.

Abstract: A chromatic dispersion-compensating fiber adapted to compensate the chromatic dispersion of an SMF or an NZ-DSF having positive chromatic dispersion presents chromatic dispersion which is negative and greater than or equal to −150 ps/(nm.km) at a wavelength of 1550 nm, and a theoretical cutoff wavelength longer than 1800 nm. At 1550 nm, the fiber presents a ratio of chromatic dispersion over chromatic dispersion slope lying in the range 30 nm to 500 nm. The fiber can present a rectangle or a trapezium profile together with a buried trench and a ring. It can be used in a line or in a module to compensate the chromatic dispersion and the chromatic dispersion slope in transmission systems in which the line fiber is an SMF or an NZ-DSF having positive chromatic dispersion.

Abstract: An optical fiber exhibiting monomode behavior in-cable over a range from 1300 nm to 1625 nm and having, at a wavelength of 1550 nm: a dispersion from 5 to 11 ps/(nm.km); a ratio between dispersion and dispersion slope from 250 nm to 370 nm; a derivative of effective surface area with respect to wavelength less than or equal to 0.14%/nm; a chromatic dispersion cancellation wavelength &lgr;0 less than or equal to 1370 nm; and an effective surface area greater than or equal to 50 &mgr;m2. The proposed criteria limit variations in non-linear effects in the fiber over a wide range of wavelengths and limit the dispersion to be compensated; also, the fiber can be compensated in a transmission system by chromatic dispersion compensating fiber used conventionally for stepped index fiber. The limit on the effective surface area slope avoids the need to treat individually the various wavelengths used in the transmission system.

Abstract: The invention proposes an optical fiber presenting a reference index profile having more than six steps. At a wavelength of 1550 nm it presents chromatic dispersion that is positive, and a ratio of the square of effective area over chromatic dispersion slope that is greater than 100,000 &mgr;m4.nm2.km/ps. The invention makes it possible to improve the propagation characteristics of prior art fibers by optimizing index profile. It can be implemented using conventional techniques for building up preforms by VAD or by MCVD.

Abstract: The fiber is adapted to compensate chromatic dispersion and chromatic dispersion slope of a positive chromatic dispersion optical fiber in the U band from 1625 nm to 1675 nm. In that band it has negative chromatic dispersion, negative chromatic dispersion slope, and a chromatic dispersion over chromatic dispersion slope ratio from 100 nm to 600 nm. At a wavelength of 1650 nm it has bending losses less than 100 dB/m with the fiber wound around a 10 mm radius former and bending losses less than 5×10−3 dB with 100 turns of the fiber wound around a 30 mm radius former. The dispersion compensating fiber can be used to produce broadband transmission systems for signals with wavelengths up to 1675 nm.

Abstract: A chromatic dispersion-compensating fiber adapted to compensate the chromatic dispersion of a step index monomode fiber in band S presents chromatic dispersion of less than −40 ps/(nm.km) around 1475 nm, chromatic dispersion slope of less than −0.16 ps/(nm2.km), and an effective area greater than or equal to 14 &mgr;m2 around said wavelength value. The fiber is monomode at 1475 nm. The fiber can present a rectangle profile with a buried trench and a ring. It serves to compensate chromatic dispersion and chromatic dispersion slope for transmission systems in band S using a step index monomode fiber as the line fiber.

Abstract: 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: C g C g ′ × 1 1 + C cum / ( L g · C g

Abstract: An optical fiber in which propagation is monomode propagation when incorporated into a cable has, at a wavelength of 1 550 nm, a chromatic dispersion from 3 ps/(nm.km) to 14 ps/(nm.km) and an absolute value of chromatic dispersion slope less than 0.014 ps/(nm2.km), and, at a wavelength of 1 625 nm, bending losses measured for a 10 mm radius less than 400 dB/m. The proposed criteria allow use of the fiber over a wide band of wavelengths in a wavelength division multiplex transmission system. The low chromatic dispersion slope simplifies the management of chromatic dispersion in the transmission system.

Abstract: The invention provides a step index optical fiber which presents cladding having an index lower than the index of silica and a core with an index higher than the index of silica. The fiber is obtained by drawing a preform made by chemical vapor deposition using a deposition tube of index lower than the index of silica. Inner cladding of index substantially equal to the index of the deposition tube, and then a core of index higher than the index of the inner cladding are deposited in succession therein. The invention makes it possible to obtain a fiber having a large effective area, reduced attenuation, and suitable for being fabricated at low cost by chemical vapor deposition.

Abstract: A chromatic dispersion-compensating fiber adapted to compensate the chromatic dispersion of an SMF or an NZ-DSF having positive chromatic dispersion presents chromatic dispersion which is negative and greater than or equal to −150 ps/(nm.km) at a wavelength of 1550 nm, and a theoretical cutoff wavelength longer than 1800 nm. At 1550 nm, the fiber presents a ratio of chromatic dispersion over chromatic dispersion slope lying in the range 30 nm to 500 nm. The fiber can present a rectangle or a trapezium profile together with a buried trench and a ring. It can be used in a line or in a module to compensate the chromatic dispersion and the chromatic dispersion slope in transmission systems in which the line fiber is an SMF or an NZ-DSF having positive chromatic dispersion.

Abstract: At a wavelength of 1 550 nm an optical fiber has a chromatic dispersion from −12 to −4 ps/(nm.km) and a ratio of chromatic dispersion to chromatic dispersion slope from 250 to 370 nm. Its index profile comprises a rectangle or trapezium with a buried trench and a ring. An optical fiber transmission system uses this kind of fiber to compensate cumulative chromatic dispersion in a line fiber that has at a wavelength of around 1 550 nm a chromatic dispersion from 5 to 11 ps/(nm.km) and a ratio of chromatic dispersion to chromatic dispersion slope from 250 to 370 nm.

Abstract: 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: 1 C g C g ′ × 1 1 + C cum / ( L g · C g ′ · Δ ⁢   ⁢ λ ) ≤ C C ′ ≤ C g C g ′ × 1 1 - C cum / ( L g · C g ′ · Δ ⁢   ⁢ λ ) ( 1 ) &LeftBracketingBar; C ′ C ′′ &RightBracketingBar; ≥ Max ⁡ ( Δ ⁢   ⁢ λ 2 × ( C · C g ′ C ′ · C g × ( 1 ± C cum L g · C g ′ · Δ ⁢   ⁢ λ ) - 1 ) - 1 ) ( 2 )

Abstract: A chromatic dispersion-compensating fiber adapted to compensate the chromatic dispersion of a step index monomode fiber in band S presents chromatic dispersion of less than −40 ps/(nm·km) around 1475 nm, chromatic dispersion slope of less than −0.16 ps/(nm2·km), and an effective area greater than or equal to 14 &mgr;m2 around said wavelength value. The fiber is monomode at 1475 nm. The fiber can present a rectangle profile with a buried trench and a ring. It serves to compensate chromatic dispersion and chromatic dispersion slope for transmission systems in band S using a step index monomode fiber as the line fiber.

Abstract: An optical fiber exhibiting monomode behavior in-cable over a range from 1300 nm to 1625 nm and having, at a wavelength of 1550 nm: