196 results about "Zero-dispersion wavelength" patented technology

An optical waveguide fiber having a high threshold for stimulated Brillouin scattering. The optical fiber preferably has large optical effective area, and further preferably has a low zero dispersion wavelength.

Disclosed is an optical fiber having a silica-based core comprising an alkali metal oxide a silica-based core, said core comprising an alkali metal oxide selected from the group consisting of K₂O, Na₂O, LiO₂, Rb₂O, Cs₂O and mixtures thereof in an average concentration in said core between about 10 and 10000 ppm by weight, and a silica-based cladding surrounding and directly adjacent the core, the cladding including a region having a lower index of refraction than the remainder of such cladding. By appropriately selecting the concentration of alkali metal oxide dopant in the core and the cladding, a low loss optical fiber may be obtained which exhibits a cable cutoff less than 1400 nm chromatic dispersion at 1550 nm between about 13 and 19 ps/nm/km, and a zero dispersion wavelength less than about 1324 nm.

A single-mode optical fiber has a cut-off wavelength of 1260 nm or less, a zero-dispersion wavelength in the range of 1300 nm to 1324 nm, a zero-dispersion slope of 0.093 ps/nm²/km or less, a mode field diameter at a wavelength of 1310 nm in the range of 5.5 μm to 7.9 μm, and a bending loss of 0.5 dB or less at a wavelength of 1550 nm, the bending loss being produced when the fiber is wound around a 10-mm radius for 10 turns.

The present invention provides an optical fiber of which a zero dispersion wavelength falls within a range of between 1,250 nm and 1,350 nm inclusive, transmission loss at 1,550 nm is equal to or less than 0.185 dB/km, chromatic dispersion at 1,550 nm is within the range of 19±1 ps/nm·km, a dispersion slope at 1,550 nm is equal to or less than 0.06 ps/nm²·km, an effective area A_eff is equal to or more than 105 μm², a cable cutoff wavelength λ_cc is equal to or less than 1,530 nm, polarization mode dispersion is equal to or less than 0.1 ps/km^1/2, and a loss when the optical fiber is wound on a mandrel having an outer diameter of 20 mm is equal to or less than 10 dB/m.

A pulse laser apparatus includes a laser configured to generate a pulse of a laser beam, a fiber amplifier, and a pulse compressor. The fiber amplifier includes a rare-earth doped fiber that exhibits normal dispersion at a wavelength of the laser beam generated from the laser. The pulse laser apparatus further includes a unit configured to give a loss to energy portions in a wavelength region corresponding to a zero-dispersion wavelength of the rare-earth doped fiber and/or a wavelength region longer than the zero-dispersion wavelength within a wavelength spectrum of the laser beam having been chirped in the fiber amplifier.

This invention relates to a bending-insensitive single module optics fiber and its process method. Its wave-guide structure comprises core layer and cover layer. Its process adopts PCVD work that the materials are burned solid without the oxygen and Freon with different proportions to get the fiber. The fiber bending consumption lies between 1310nm wavelength and 1550nm wavelength relative to regular 0.652 fibers and its fiber module field diameter is 7í‚0.8ª–m and its zero color diffusion wavelength is near 1310nm.

An optical fiber, which has a zero-material dispersion wavelength equal to or greater than 2 μm, and a high nonlinear susceptibility χ³ equal to or greater than 1×10⁻¹² esu, and uses tellurite glass having sufficient thermal stability for processing into a low loss fiber, employs a PCF structure or HF structure having strong confinement into a core region. This enables light to propagate at a low loss. The size and geometry of air holes formed in the core region, and the spacing between adjacent air holes make it possible to control the zero dispersion wavelength within an optical telecommunication window (1.2-1.7 μm), and to achieve large nonlinearity with a nonlinear coefficient γ equal to or greater than 500 W⁻¹ km⁻¹.

An optical waveguide fiber having a high threshold for stimulated Brillouin scattering. The optical fiber preferably has large optical effective area, and further preferably has a low zero dispersion wavelength.

A supercontinuum light emitting device comprises an effectively CW light source producing light of wavelength λ₁ within a specified bandwidth and a nonlinear fiber optically coupled to the light source. The nonlinear fiber has a plurality of fiber segments with different zero dispersion wavelengths λo_i, where each successive fiber segment has zero dispersion wavelength λo_i which is larger than the zero dispersion wavelength of the preceding fiber and the zero dispersion wavelength of the first fiber segment is within ±20 nm of λ₁.

Disclosed is a wide-band dispersion controlled optical fiber. The optical fiber enables the use of optical signals in various wavelength regions in a wavelength division multiplexing mode communication network by controlling the position of the zero dispersion wavelength, and enables long distance transmission by controlling dispersion slope and bending loss. Furthermore, there is an advantage in that the optical fiber enables not only short distance transmission but also middle/long distance transmission using a single type of optical fiber because the optical fiber is controlled to have negative dispersion values in the O-band wavelength region and positive dispersion values with small deviations in the C-band and L-band wavelength regions.

An apparatus and methods for generating a substantially supercontinuum-free widely-tunable multimilliwatt source of radiation characterized by a narrowband line profile. The apparatus and methods employ nonlinear optical mechanisms in a nonlinear photonic crystal fiber (PCF) by detuning the wavelength of a pump laser to a significant extent relative to the zero-dispersion wavelength (ZDW) of the PCF. Optical phenomena employed for the selective up-conversion in the PCF include, but are not limited to, four-wave mixing and Cherenkov radiation. Tunability is achieved by varying pump wavelength and power and by substituting different types of PCFs characterized by specified dispersion properties.

An optical amplifier includes an optical gain fiber into which signal light and pump light are input and at least one relative phase shifter is inserted. Preferably, the relative phase shifter is inserted so that the relative phase in the lengthwise direction of the optical gain fiber falls within a predetermined range containing 0.5 Π. Preferably, the optical gain fiber is a highly non-linear optical fiber having a non-linearity constant of at least 10/W/km. Preferably, the dispersion of the optical gain fiber is within the range from −1 ps/nm/km to 1 ps/nm/km in an amplification band. Preferably, the absolute value of the dispersion slope of the optical gain fiber at a zero dispersion wavelength is no greater than 0.05 ps/nm²/km.

An optical waveguide fiber having a zero-dispersion wavelength less than 1450 nm, a dispersion slope at a wavelength of 1550 of less than 0.06 ps/nm²/km nm, and attenuation at a wavelength of 1550 nm less than 0.190 dB/km. Optical fibers are disclosed that exhibit an effective area at a wavelength of 1550 nm of greater than 50 μm², and dispersion at a wavelength of 1550 nm between 5 and 15 ps/nm-km.

There is disclosed an optical fiber wherein an absolute value of the fourth order dispersion β₄ of fourth derivative β₄ of propagation constant β with respect to angular frequency ω at a mean zero dispersion wavelength λ₀ in an overall length is not more than 5×10⁻⁵⁶ s⁴/m and wherein a fluctuation of a zero dispersion wavelength along a longitudinal direction is not more than ±0.6 nm.

An optical fiber for an optical network is disclosed. The optical fiber includes a core having a core region having a first refractive index N₁, and a refractive index depressed region surrounding the core region and having a second refractive index N₂ that is lower than the first refractive index. A clad surrounds the core and having a third refractive index N₄. The optical fiber has a zero-dispersion wavelength that is not less than 1555 nm and positioned in a wavelength range which does not exceed L-band. The optical fiber has negative dispersion values in C-band and positive dispersion values in L-band.

The invention relates to a low dispersion slope dispersion-shifted single-mode fiber for large capacity transmission comprising a core and a cladding. Said fiber is characterized in that said core has three to five core segments having different refractive index profiles, and said cladding has four to six cladding segments. The total dispersion slope of said fiber at 1550 nm is less than 0.060 ps/nm²·km, the zero dispersion wavelength is less than 1420 nm, the effective area ranges from 55 μm² to 65 μm², and the dispersion in the region of 1530 nm˜1565 nm ranges from 5.0 ps/nm²·km to 12.0 ps/nm²·km. The fiber has low dispersion slope, moderate dispersion, low attenuation, and excellent bend resistance performance. It is suitable for a high-speed (10 Gbits/s and 40 Gbits/s), large capacity, and long distance DWDM system. Therefore, not only the non-linear problem that fazes high-speed communication is solved effectively, but also the DWDM transmission at 10 Gbits/s can be realized within a wider wavelength range. In addition, low dispersion slope is advantageous for comprehensive management of dispersion, so that the requirement for long distance non-electric relay can be fulfilled.

In a wavelength division multiplexed optical transmission system wherein the zero dispersion wavelength of the optical fiber transmission path 224 is in the 1550 nm region, among multiplexed optical signals, the wavelengths of either of at least two optical signals are allocated between 1450 nm and 1530 nm, or between 1570 mn and 1650 nm.