MXPA01002562A

MXPA01002562A - Positive dispersion low dispersion slope fiber

Info

Publication number: MXPA01002562A
Application number: MXPA/A/2001/002562A
Authority: MX
Inventors: Daiping Ma; David K Smith
Original assignee: Corning Incorporated; Daiping Ma; David K Smith
Priority date: 1998-09-11
Filing date: 2001-03-09
Publication date: 2001-11-21

Abstract

Disclosed is a single mode optical waveguide having a segmented core of at least two segments. The relative refractive index, the index profile and the radial dimensions of the core segments are selected to provide an optical waveguide fiber having properties suitable for a high performance telecommunication system operating in the wavelength window of about 1530 nm to 1570 nm. Embodiments of the invention having two, three and four segments are described. To eliminate non-linear effects, such as FWM and SPM, which occur in a high performance, high rate systems, the effective area of the waveguide is made to be greater than about 60&mgr;m2, more preferably greater than 65&mgr;m2, and most preferably greater than 70&mgr;m2. The total dispersion is preferably positive and equal to at least 2 ps/nm-km at 1530 nm. This total dispersion together with a total dispersion slope less than about 0.1 ps/nm2-km insures a minimum FWM effect over the wavelength window.

Description

FIBER OF INCLINATION PE LOW DISPERSION. POSITIVE DISPERSION CROSS REFERENCE TO RELATED REQUESTS This application claims the benefit of the provisional patent application of E.U.A. No. 60 / 099,979, filed on 9/11/98 and the provisional patent application of E.U.A. No.60 / 103,080, filed on 10/5/98 and the provisional patent application of E.U.A. No.60 / 130,652, filed on 04/23/99.

BACKGROUND OF THE INVENTION This invention is directed to a single-mode optical waveguide fiber, more particularly to a waveguide fiber in which the total dispersion remains positive over the entire fiber length. In addition, the effective area is high and the total dispersion inclination is kept at a low value. Due to the high information rates and the need for long regenerator space, the search for high performance optical waveguide fibers designed for long-range and high-bitrate telecommunications has been intensified. An additional requirement is that the waveguide fiber be compatible with optical amplifiers, which typically show an optimal gain curve on the 1530 nm wavelength scale at 1570 nm. The potential to expand the usable wavelength in the L-band scale from about 1570 nm to 1700 nm, most preferably in the range of about 1570 nm to 1625 nm, is also considered. In cases where the waveguide information capacity is increased by wavelength division multiplexing (WDM) technology, an additional waveguide fiber property becomes important. For WDM, high bit rate systems, the waveguide must have an exceptionally low total dispersion, but not zero, thus limiting the non-linear dispersion effect of four wave mixing. Another non-linear effect that can produce unacceptable dispersion in systems that have a high power density, i.e., a high power per unit area, is the autophase modulation. The autophase modulation can be controlled by designing a waveguide core that has a large effective area, thus reducing the power density. An alternative approach is to control the sign of the total dispersion of the waveguide so that the total dispersion of the waveguide serves to counteract the dispersive effect of the autophase modulation. A waveguide that has a positive dispersion, where positive means that shorter wavelength signals travel at a higher speed than those of the longer wavelength, will produce a scatter effect opposite to that of the autophase modulation. , thus substantially eliminating the scattering of autophase modulation.

Said waveguide fiber is described in the patent application of E.U.A. 08 / 559,954. The novel profile of the present invention improves fiber 08 / 559,954 by increasing the effective area. In addition, the waveguide of this description has a total dispersion over the operation wavelength window that is positive everywhere and has a lower limit greater than about 2.0 ps / nm-km to further reduce the error margin of power due to the mixing of four waves. Therefore, there is a need for an optical waveguide fiber which: - is in a single mode on at least the wavelength scale 1530 nm to 1570 nm; - have a dispersion wavelength of zero outside the 1530 nm to 1570 nm scale; - have a positive total dispersion on the wavelength scale 1530 nm at 1570 nm which is not less than about 2.0 ps / nm-km but which is low enough to avoid a margin of error of considerable linear dispersion power; - have a usable transmission window on the scale of approximately 1570 nm to 1625 nm; and - retains the usual high performance waveguide characteristics such as high resistance, low attenuation and acceptable resistance to loss induced by bending.

The concept of adding structure to the waveguide fiber core by core segments, which have different profiles to provide flexibility in the waveguide fiber design, is fully described in the U.S. patent. 4,715,679, Bhagavatula. The concept of a segmented core can be used to obtain unusual combinations of waveguide fiber properties, such as those described herein.

Definitions The following definitions are in accordance with the common usage in the art. - The refractive index profile is the ratio between the refractive index and the waveguide fiber radius. A segmented core is one that has at least one first and second waveguide fiber core radio segments. Each radio segment has a respective refractive index profile. - Radii of the core segments are defined in terms of the initial and final points of the segments of the refractive index profile. Figure 1 illustrates the definitions of radius used in the present. The radius of the central index segment 10, is the length 2 extending from the central waveguide line to the point at which the profile becomes the a-profile of segment 12, that is, the selected point to start the calculation of the relative index using the a-profile equation. The radius of segment 12 extends from the center line to the radial point at which the extrapolated descending portion of the a-profile crosses the extrapolated extension of profile segment 14. The radius of segment 14 extends from the centerline to the radius point in which the%? is half the maximum value of%? of segment 16. The width of segment 16 is measured between the percentage values of half of%? of segment 16. The radius of segment 16 extends from the centerline to the midpoint of the segment. It is clear that many alternative definitions of segment dimensions are available. The definitions set forth herein were used in a computer model that predicts waveguide properties given a refractive index profile. The model can also be used to provide a family of refractive index profiles that will have a preselected series of functional properties. - The effective area is Aeff = 2p (ÍE2 r dr) 2 / (/ E4 r dr), where the integration limits are 0 to oo, and E is the electric field associated with the propagated light. An effective diameter, Derf can be defined as, - The profile volume is defined as 2Ír.r2%? r dr. The internal profile volume extends from the central waveguide line, r = 0, to the crossing radius. The external profile volume extends from the crossing radius to the last point of the core. The units of the profile volume are% μm2 because the relative index has no dimensions. The profile volume units,% μm2, will simply be called units throughout this document. - The crossing radius is found from the power distribution dependence on the signal as signal wavelength changes. On the internal volume, the signal strength decreases as the wavelength increases. On the external volume, the signal strength increases as the wavelength increases. - The initials WDM represent wavelength division multiplexing. - The initials SPM represent autophase modulation, a nonlinear optical phenomenon where a signal having a power density above a specific power level will travel at a different speed in the waveguide relative to a signal below that power density. SPM causes signal dispersion comparable to that of the linear dispersion that has a negative sign. - The initials FWM represent mixed four waves, the phenomenon where two or more signals in a waveguide interfere to produce signals of different frequencies. - The term,% ?, represents a relative measure of the refractive index defined by the equation,%? = 100x (n2-nc2) / 2n¡2, where n¡ is the maximum refractive index in region i, unless specify something else and nc is the refractive index of the coating region unless otherwise specified. - The term alpha profile, a-profile, refers to a profile of refractive index, expressed in terms of%? (b), where b is radius, which follows the equation,%? (b) =? (b0) (1- [l b-b0l / (b? -b0)] a), where b0 is the maximum point of the profile and i is the point at which%? (b) is zero and b is on the scale b¡ <; b < bf, where delta is defined above, bi is the starting point of the a-profile, bf is the endpoint of the a-profile, and a is an exponent that is a real number. The start and end points of the a-profile are selected and entered into the computer model. As used here, if an a-profile is preceded by a step-by-step index profile, the starting point of the a-profile is the intersection of the a-profile and the step profile. The diffusion at this intersection is not taken into account in the model. Therefore, when assigning an initial point of an a-profile to a profile that includes diffusion, the form of the a-profile and the index profile form by steps are extrapolated to find their point of intersection. A final point of an a-profile for the case where the a-profile is followed by a step-by-step index profile is found in an analogous way. In the model, in order to cause a continuous union of the a-profile with the profile of the adjacent profile segment, the equation is rewritten as:%? (B) =? (Ba) + [? (B0) -? (Ba )]. { (1 - [| b-b0 | / (b b0)] a.}., Where ba is the first point of the adjacent segment.

- The pin bend bend test is used to compare the relative strength of waveguide fibers to bending. To perform this test, the loss of attenuation is measured when the waveguide fiber is arranged so that loss due to induced bending does not occur. This waveguide fiber is then woven around the pin arrangement and the attenuation is measured again. The loss induced by bending is the difference between the two attenuation measurements. The pin arrangement is a series of ten cylindrical pins arranged in a single row and held in a fixed vertical position on a flat surface. The separation of pins is 5 mm, from center to center. The diameter of the pins is 0.67 mm. The waveguide fiber is caused to pass on opposite sides of adjacent pins. During the test, the waveguide fiber is placed under a tension just enough to make the waveguide conform to a portion of the periphery of the pins.

BRIEF DESCRIPTION OF THE INVENTION The novel single mode waveguide fiber described herein meets the requirements listed above and, moreover, lends itself to reproducible manufacturing. The novel single-mode fiber has a segmented core of at least two segments, each segment characterized by a refractive index profile, a relative index%, and a radius. The characteristics of the core segment are selected to provide a particular series of properties suitable for a telecommunications system designed to operate in the 1550 nm window, typically in the range of about 1530 nm to 1570 nm. A preferred scale has an operating wavelength window extending to approximately 1625 nm. The system may include optical amplifiers, WDM operation, and relatively high signal amplitudes. To substantially eliminate non-linear effects, such as FWM and SPM, which occur in high-speed and high-performance systems, the effective area of the waveguide is made to be greater than about 60 μm2, preferably greater than 65 μm2, and most preferably greater than 70 μm2. The total dispersion is preferably positive and equal to at least 2 ps / nm-km at 1530 nm. This total dispersion together with a total dispersion slope of less than about 0.1 ps / nm2-km ensures a minimum FWM effect on the wavelength window. The mode field diameter over the wavelength band 1530 nm at 1570 nm and up to 1625 nm is large, on the scale of about 8.8 μm to 10.6 μm to provide ease in dividing the fibers. Fiber profiles having an attenuation of less than 0.25 dB / km both at 1550 nm and 1625 nm have been made according to the invention. In a novel waveguide fiber embodiment, in addition to each of the segments being characterized by a refractive index profile, a radial extension, and a positive relative index percentage, at least one of the segments has an a -profile. A coating glass layer surrounds and is in contact with the core. The modalities of the novel waveguide include, but are not limited to, those that have two, three and four segments. The particular characteristics of these modalities are shown in the tables and examples that appear later. In the embodiment series illustrated in Figures 5 and 6, the novel waveguide fiber has an a-profile on the scale of about 0.8 to 3.3, and most preferably on the scale of 0.95 to 3.16. The relative index%? it is higher in the segment that has an a-profile shape, and is lower on the step index form that joins the a-profile. The outermost segment has a%? between that of the central and second segments. Also included are embodiments having desired dispersion and field diameter at 1625 nm. In particular, at 1625 nm, the waveguide fiber has a total dispersion less than about 13 ps / nm-km and preferably less than about 11.5 ps / nm-km. The present invention also relates to optical fiber performas, and methods for manufacturing such optical fiber performas, having a refractive index profile such that, when the optical fiber preform is stretched on a waveguide fiber, The waveguide fiber includes a segmented core having at least two segments, each of the segments having a radius r, a refractive index profile and a relative refractive index percentage,%, where i is equal to the number of segments and a coating layer that surrounds and is in contact with the core, the coating layer having a refractive index nc; wherein, the r,%, and the refractive index profiles originate fibers having the properties and characteristics that are also described herein. Such fiber optic preforms can be manufactured using any of the techniques known in the art, including chemical vapor deposition techniques such as OVD, IV, MCVD, and VAD. In a preferred embodiment, a soot preform is fabricated using an OVD technique having the desired refractive index profile. This soot preform is then consolidated and stretched in a waveguide fiber.

BRIEF DESCRIPTION OF THE FIGURES Figure 1 illustrates a core profile according to the invention showing the dimensions of the radios used in computer model calculations. Figure 2 is a graph of the relative index percentage against the core radius that illustrates a two-segment mode. Figure 3 is a graph of the percentage of relative index versus core radius illustrating a three-segment modality.

Figure 4 is a graph of the percentage of relative index versus core radius illustrating a four-segment modality. Figure 5 is another example of the percentage of relative index against the core radius that illustrates a three-segment modality. Figure 6 is the percentage of relative index versus core radius of an optical fiber manufactured in accordance with the objective form of Figure 5.

DETAILED DESCRIPTION OF THE INVENTION The novel waveguide fiber comprises a family of segmented core designs that produce a very particular series of desired functional parameters. The family of core designs includes, but is not limited to, modalities that have two, three, and four segments. The desired characteristics include a lower dispersion zero wavelength than the operation window which is on the scale of about 1530 nm to 1570 nm, called the C-band and may include wavelengths at about 1625 nm which is found in the upper end of the L-band, which refers to a wavelength scale of about 1570 nm to 1625 nm. The total dispersion is preferably not less than about 2 ps / nm-km in the operation window and the dispersion inclination is low, less than about 0.10 ps / nm2-km, to ensure a limited power margin of error due to linear dispersion. The low tilt provides a total dispersion at 1625 nm no greater than approximately 13 ps / nm-km. The total dispersion at 1625 nm of less than 10 ps / nm-km has been achieved. The total dispersion of non-zero effectively eliminates FWM and the positive sign of the total dispersion shifts the signal degradation due to SPM. Tables 1, 2 and 3, which are discussed below, define the novel family of waveguide fibers that have these properties. It will be noted in the examples that follow, that the attenuation is quite low and the losses induced by bending are acceptable. Referring to Figure 2, a graph of%? against core radio in microns, it is seen that the segmented core has two segments. This is a special case of the waveguide fiber described in Table 1 below, in which the second and third segments are equal% ?. Segment 18 is an alpha profile that has an alpha of about 1. The second segment 20 is a step index profile, which has an external radius determined from the width and external radius given in table 2. This external radius is the mid-point radius defined above. It is drawn at the midpoint of the width of the third segment. Compensation has been made for spreading of central line impurifier by increasing the rate of flow of dopant during placement of the central portion of the preform. The amount of the doping increase is preferably determined empirically by adding different amounts of doping agent to the centerlines of various preforms, then processing the preforms through the waveguide fiber. The curved portions 22 and 24 of the profile result from the diffusion of doping material. In general, the radios included in the model calculations do not take this diffusion into account, because the diffusion effect such as that shown in Figure 2 in the profile portions 22 and 24 is small. In any case, diffusion can be compensated by making adjustments to other portions of the refractive index profile.

EXAMPLE 1 Profile of three segments A fiber was modeled according to Figure 3 and had the following configuration. Counting the segments consecutively, starting with 1 in the center line, and using the definitions provided above, the core design was%? I approximately 0.70%, ri approximately 0.39 μm,%? 2 approximately 0.74, r2 approximately 2.84 μm, %? 3 about 0.05% and rz, drawn from the center line to the midpoint of step 20, approximately 5.09 μm. The width of segment 3 was approximately 4.5 μm. The percentage of relative index in the center line was approximately 0.7 and extended to a radius of approximately 0.39 μm, at which point the a-profile began. The a is approximately 1.

This waveguide fiber had the predicted properties: - zero dispersion wavelength,? 0, of 1501 μm; - total dispersion at 1540 nm of 3.11 ps / nm-km; - total dispersion at 1560 from 4.71 ps / nm-km; - total dispersion inclination 0.08 ps / nm2-km; - cutting wavelength,? c, 970 nm measured in the fiber; - effective area, Aeff, 72.7 μm2; and, - attenuation at 1550 nm of 0.196 dB / km. The loss due to bending of the pin arrangement was 87 dB. A section of the waveguide was weighted laterally and it was found that the loss by bending was 0.72 dB / m at 1550 nm.

EXAMPLE 2 Profile of three segments A second three-segment core waveguide was modeled according to the refractive index profile shown in Figure 3. In this case, the a-profile 26 started at the center line and had%? I of 0.63,? of 3.69 μm. The second segment 28 had a step profile and%? 2 of 0.018. The third segment 30 had a step profile and%? 3 of 0.12%, r3, the midpoint radius defined above, 8.2 μm and a width of 4.23 μm. This waveguide fiber had the predicted properties: - zero dispersion wavelength,? 0, of 1495 μm; - total dispersion at 1540 nm of 3.37 ps / nm-km; - total dispersion at 1560 of 4.88 ps / nm-km; - Total dispersion inclination 0.075 ps / nm2-km; - cutting wavelength,? c, 1648 nm measured in the fiber; and - effective area, Aeff, 72.8 μm2. The loss by doubling of pin arrangement was 15.3 dB. A section of the waveguide was weighted laterally and it was found that the loss by bending was 0.75 dB / m at 1550 nm. In this case the properties are excellent and the loss by bending is greatly improved over the design of example 1. Stripe lines 32 and 34 in Figure 3 are included to illustrate alternative three-segment core designs. It will be understood that the design of Figure 3 includes index profiles where segments 28 and 30 deviate slightly from a stepwise index configuration. For example, the segments could have a small positive or negative inclination. Although the diffusion of doping agent is shown in the segment boundaries in Figure 3, the model calculations did not include this diffusion. The same is true of all model calculations contained therein.

EXAMPLE 3 Profile of four segments A waveguide fiber with a profile was modeled according to Figure 4. The first segment 36 had a relative index on the centerline of 0.23, λi of 0.28 at the radius of the outer segment n, as defined above, which was 1.36 μm. The a-profile 38 had an a of 0.388,% 2 of 1.73, and an outer segment radius r2 of 3.17 μm. The step index portion 40 had%? 3 of 0.17 and the index portion by steps 42 had%? 4 of 0.17, r4 of 7.3 μm and a width of 3.50 μm. This waveguide fiber had the predicted properties: - zero dispersion wavelength,? 0, of 1496 μm; - total dispersion at 1540 nm of 3.47 ps / nm-km; - total dispersion at 1560 of 5.06 ps / nm-km; - total dispersion inclination 0.08 ps / nm2-km; - cutting wavelength,? c, 1750 nm, measured in the fiber; - effective area, Aeff, 72.7μm2, and, attenuation at 1550 nm, A1550, of 0.212 dB / km. The loss by doubling of pin arrangement was 6.16 dB. A section of the waveguide was weighted laterally and it was found that the loss by bending was 0.74 dB / m at 1550 nm. In this example the properties are again excellent and the resistance to bending especially good.

The examples indicate a major interchange between the simplicity of the index profile versus the resistance to bending, the resistance to bending improving as the complexity of the profile increases. To find the extent of parameter variation that could occur in the profile while continuing to provide the desired properties, the model calculations were made to a series of points in a space that has an axis corresponding to each profile variable. Tables 1 to 3 illustrate preferred waveguide functional parameters of arrangements according to the invention which result in obtaining the desired properties. The parameters are illustrated in Table 1 for a first three-segment design, Table 2 for a second three-segment design, and Table 3 for the four-segment design. These tables set forth the refractive index profile limits of waveguide fiber, that is, limits on radii and relative index%, as well as the properties that are derived from them.

EXAMPLE 4 Three segment design Another example of the three-segment design was modeled and produced excellent results. Referring to figure 5, segment 46, an a-profile with a of 1.33, it has%? I of 0.64, n of 3.72 μm, segment 48, a step index, it has%? 2 of 0.008, z of 4.5 μm , segment 50, a step index, has%? 3 of 0.14, midpoint radius r is 7.43 μm and the width of segment 50 is 4.49 μm. The central line diffusion compensation provided in segment 44 has a relative center line index of 0.7 that extended to a radius of 0.39 μm. This waveguide fiber has the predicted properties: - zero dispersion wavelength,? 0, of 1501 μm; - total dispersion at 1530 nm of 2.53 ps / nm-km; - total dispersion at 1565 of 5.47 ps / nm-km, - total dispersion inclination 0.084 ps / nm2-km; - cut-off wavelength,? c, 1280 nm, measured in wired form; - effective area, ATff, 72.5 μm2; and, - attenuation at 1550 nm of 0.195 dB / km - mode field diameter, 9.8 μm - internal volume, 1.61 units, and, - external volume 4.90 units.

EXAMPLE 5 Manufacturing results A large number of fibers were manufactured according to the model profile of Figure 5. The refractive index profile as measured is shown in Figure 6. The target values of the fiber parameters were as follows. The slit in the center line had a%? lower of 0.55% a radius of 0.39 μm. The a-profile had an a of 1,335, a%? of 0.64%, and a radius of 3.72 μm. He % ? of the second segment was 0.008. He % ? of the third segment was 0.137, the midpoint radius was 7.43, and the segment width was 4.49 μm. The average properties of the fibers were tabulated as follows.

These are excellent results that meet or exceed the desired waveguide fiber properties. The attenuation 1625 nm for this waveguide fiber was also less than 0.25 dB / km. The following tables effectively define the family of refractive index profiles that produce the desired waveguide fiber function. Are the% exposed? maximum and minimum of each segment in particular, as well as corresponding radii r, for each segment. The cases in which radio measurements are taken at the midpoint of a segment are marked in the header of the table. All other radii are the external radii of a given segment as well as the minimum internal radii of the next adjacent segment, where the segments are counted starting at 1 in the center and continuing outward. These other radii are measured at the intersection extrapolated between segment profiles. The width refers to the width of the segment whose radius is measured at its midpoint.

TABLE 1 TABLE 2 TABLE 3 Although particular examples of the novel waveguide have been described herein, the invention is, however, limited only by the following claims.

Claims

NOVELTY OF THE INVENTION CLAIMS 1. - A single-mode optical waveguide fiber comprising: a segmented core having at least two segments, each of the segments having a radius?, A refractive index profile and a percentage of positive relative refractive index ,%? ¡, Where i is equal to the number of segments, and a coating layer that surrounds and is in contact with the core, the coating layer having a refractive index nc; wherein, r,%, and the refractive index profiles are selected to provide: zero dispersion wavelength on the scale of about 1465 nm to 1530 nm; Total dispersion at 1530 nm > 2 ps / nm-km; total dispersion inclination < 0.1 ps / nm2-km on the wavelength scale 1530 nm at 1570 nm; effective area > 60 μm2; and, mode field diameter, on the wavelength scale from 1530 nm to 1570 nm, on the scale of about 8.8 μm to 10.6 μm. 2. The single-mode optical fiber according to claim 1, further characterized in that the total dispersion at 1625 nm is not greater than about 13 ps / nm-km. 3. The single-mode optical fiber according to claim 1, further characterized in that at least one of the segments has an a-profile. 4. - The single-mode optical fiber according to claim 3, further characterized in that the core has a central line and at least three segments, a first segment starting at approximately the center line and having an a-profile with a value of of about 1, a second segment joining the first segment and having a step index profile, and a third segment joining the second segment and having a step index profile. 5. The single-mode optical fiber according to claim 4, further characterized in that the internal volume of the core is in the range of approximately 1.21 units to 1.68 units, the external volume is in the range of approximately 1.65 units to 5.95. units, and the ratio of the internal volume to the external volume is on the scale of approximately 0.25 to 0.76. 6. The single-mode optical fiber according to claim 4, further characterized in that the first segment has a% ?? on the scale of about 0.7 to 1.07, a radius n on the scale of about 2.4 to 4.17 μm, the second segment has a% 2 on the scale of about 0.00 to 0.14%, and the third segment has a%? 3 on the scale from about 0.06 to 0.16, a midpoint radius on the scale of about 3.95 to 10.11 μm and a width on the scale of about 3.10 to 6.52 μm. 7. The single-mode optical fiber according to claim 3, further characterized in that the core has a central line and at least three segments, a first segment starting at the center line and having an a-profile with 1 a value from a on the scale of approximately 0.97 to 3.16, a second segment that joins the first segment and that has a step-by-step index profile, and a third segment that joins the second segment and that has a step-by-step index profile. 8. The single-mode optical fiber according to claim 7, further characterized in that the internal volume of the core is in the range of approximately 1.36 units to 1.84 units, the external volume is in the range of approximately 2.17 units to 6.10. units, and the ratio of internal volume to external volume is on the scale of approximately 0.24 to 0.70. 9. The single-mode optical fiber according to claim 7, further characterized in that the first segment has a% ?? on the scale of about 0.54 to 0.83, a radius n on the scale of about 2.73 to 3.82 μm, the second segment has a% 2 on the scale of about 0.08 to 0.14%, and the third segment has a%? 3 on the scale of approximately 0.06 to 0.09, a half point radius r $ on the scale of about 5.76 to 10.25 μm and a width on the scale of about 1.36 to 9.32 μm. 10. The single-mode optical fiber according to claim 7, further including a relative index slit in the center line, the slit being no more than about 0.20%? less than? -i, and the radius of the slit not being greater than about 0.4 μm. 11. The optical waveguide fiber according to claim 9 or 10, further characterized in that the total dispersion at 1625 nm is not greater than about 13 ps / nm-km. 12. The single-mode optical fiber according to claim 4, further characterized in that the core has a central line and four segments, a first segment starting at the center line and having an index profile having a first delta value in the center line and a second delta value in its radius, where the index profile is a curve, the curve being determined by an interpolation curve adjustment based on the first and second delta values, a second segment that joins the first segment and having an a-profile with a value a on the scale of approximately 0.22 to 0.394, a third segment that joins the second segment and that has an index profile by steps, and a fourth segment that joins the third segment and that has an index profile by steps. 13. The single-mode optical fiber according to claim 12, further characterized in that the internal volume of the core is in the range of approximately 1.27 units to 1.89 units, the external volume is in the range of approximately 2.05 units to 5.87. units, and the ratio of internal volume to external volume is on the scale of approximately 0.25 to 0.77. 14. - The single-mode optical fiber according to claim 12, further characterized in that the first segment has a% ?? on the scale of about 0.12 to 0.72 and a relative index on the center line on the scale of about 0.23 to 0.24, a radius n on the scale of about 1.13 to 1.39 μm, the second segment has a% 2 on the scale of approximately 1.68 to 2.38%, a radius on the scale of approximately 2.25 to 3.29 μm, the third segment has a%? 3 on the scale of approximately 0.00 to 0.12, and, the fourth segment has a%? 4 on the scale of approximately 0.06 to 0.18, a midpoint radius r4 on the scale of about 5.29 to 7.39 μm and a width on the scale of about 3.38 to 8.03 μm. 15. An optical waveguide fiber preform comprising: a central core region having a refractive index profile, said core region surrounded by and in contact with a coating layer, characterized in that said fiber preform Optics is stretched to form a waveguide fiber, said preform core region profile being configured to provide a waveguide fiber that includes: a segmented core having at least two segments, each of the segments having a radius r, a refractive index profile and a relative refractive index percentage,%? ¡, where i is equal to the number of segments where%? are positive, and a coating layer that surrounds and is in contact with the core, the coating layer having a refractive index nc; wherein, r,%, and the refractive index profiles are selected to provide: zero dispersion wavelength on the scale of about 1465 nm to 1530 nm; Total dispersion at 1530 nm > 2 ps / nm-km; total dispersion inclination < 0.1 ps / nm2-km on the wavelength scale 1530 nm at 1570 nm; effective area > 60 μm2; and, mode field diameter, on the wavelength scale from 1530 nm to 1570 nm, on the scale of about 8.8 μm to 10.6 μm. 16. The optical fiber guide fiber preform according to claim 15, further characterized in that the total dispersion of the waveguide fiber at 1625 nm is not greater than about 13 ps / nm-km. 17. The optical fiber guide fiber preform according to claim 15, further characterized in that at least one of the waveguide fiber segments has an a-profile. 18. The fiber optic guide fiber preform according to claim 17, further characterized in that all% ?? fiber waveguide are positive. 19. The optical waveguide fiber preform according to claim 18, further characterized in that the waveguide fiber core has a center line and at least three segments, a first segment starting at approximately the center line and having an a-profile with a value of about 1, a second segment that joins the first segment and that has a step-by-step index profile, and a third segment that joins the second segment and that has an index profile per Steps. 20. The optical waveguide fiber preform according to claim 19, further characterized in that the internal volume of the waveguide fiber core is in the range of approximately 1.21 units to 1.68 units, the external volume is in the scale of approximately 1.65 units to 5.95 units, and the ratio of the internal volume to the external volume is on the scale of approximately 0.25 to 0.76. 21. The optical waveguide fiber preform according to claim 19, further characterized in that the first segment of the waveguide fiber core has a%? I on the scale of about 0.7 to 1.07, a radius of on the scale of approximately 2.4 to 4.17 μm, the second segment has a%? 2 on the scale of approximately 0.00 to 0.14%, and the third segment has a%? 3 on the scale of about 0.06 to 0.16, and a midpoint radius r3 on the scale of about 3.95 to 10.11 μm and a width on the scale of about 3.10 to 6.52 μm. 22. The optical waveguide fiber preform according to claim 18, further characterized in that the waveguide fiber core has a center line and at least three segments, a first segment starting at the centerline and having an a-profile with a value a on the scale of approximately 0.97 to 3.16, a second segment that joins the first segment and that has an index profile by steps, and a third segment that joins the second segment and that has a index profile by steps. 23. The optical waveguide fiber preform according to claim 22, further characterized in that the internal volume of the waveguide fiber core is in the range of approximately 1.36 units to 1.84 units, the external volume is in the scale of approximately 2.17 units to 6.10 units, and the ratio of internal volume to external volume is on the scale of approximately 0.24 to 0.70. 24. The optical waveguide fiber preform according to claim 22, further characterized in that the first segment of the waveguide fiber has a%? I on the scale of about 0.54 to 0.83, a radius ri in the scale of approximately 2.73 to 3.82 μm, the second segment has a%? 2 on the scale of approximately 0.08 to 0.14%, and the third segment has a%? 3 on the scale of approximately 0.06 to 0.09, a midpoint radius r3 on the scale of about 5.76 to 10.25 μm and a width on the scale of about 1.36 to 9.32 μm. 25. The optical waveguide fiber preform according to claim 22, further including in the waveguide fiber a slit of relative index in the center line, the slit being no more than about 0.20%? less than? -i, and the radius of the slit being no greater than about 0.4 μm. 7. The optical waveguide fiber preform according to claim 24 or 25, further characterized in that the total dispersion of the waveguide fiber at 1625 nm is not greater than about 13 ps / nm-km. 27. The single-mode fiber optic preform according to claim 18, further characterized in that the waveguide fiber core has a central line and four segments, a first segment starting at the center line and having a profile of index having a first delta value in the center line and a second delta value in its radius, where the index profile is a curve, the curve being determined by an interpolation curve adjustment based on the first and second values index delta, a second segment that joins the first segment and that has an a-profile with a value a on the scale of approximately 0.22 to 0.394, a third segment that joins the second segment and that has an index profile per steps, and a fourth segment that joins the third segment and that has an index profile by steps. 28.- The single-mode fiber optic preform according to claim 27, further characterized in that the internal volume of the waveguide fiber core is in the range of approximately 1.27 units to 1.89 units, the external volume is in the scale of approximately 2.05 units to 5.87 units, and the ratio of internal volume to external volume is on the scale of approximately 0.25 to 0.77. 29. The single-mode optical fiber preform according to claim 27, further characterized in that the first waveguide fiber segment has a%? I on the scale of about 0.12 to

1. 72, and a relative index in the center line on the scale of approximately 0. 23 to 0.24, a radius n on the scale of approximately 1.13 to 1.39 μm, the second segment has a%? 2 on the scale of approximately 1.68 a

2. 38%, a radius on the scale of approximately 2.25 to 3.29 μm, the third segment has a%? 3 on the scale of approximately 0.00 to 0.12, and, the fourth segment has a%? 4 on the scale of approximately 0.06 to 0.18 , a radius of midpoint r on the scale of about 5.29 to 7.39 μm and a width on the scale of about 3.38 to 8.03 μm.