WO2024040737A1

WO2024040737A1 - Ring-sprayed optical fiber, and optical cable

Info

Publication number: WO2024040737A1
Application number: PCT/CN2022/127615
Authority: WO
Inventors: 贺言; 乐梦龙; 李罗; 张磊; 余次龙; 罗文勇; 何茂友
Original assignee: 烽火通信科技股份有限公司
Priority date: 2022-08-25
Filing date: 2022-10-26
Publication date: 2024-02-29
Also published as: CN115437059A

Abstract

A ring-sprayed optical fiber, and an optical cable. The ring-sprayed optical fiber is a single-mode optical fiber, and comprises a natural-color optical fiber (1) and an ink-jet identifier (2), which is provided on the outer wall of the natural-color optical fiber (1), wherein the ink-jet identifier (2) comprises several ink dots (20), which are periodically distributed at intervals in the axial direction of the natural-color optical fiber (1); and an ink dot period of the ink dots (20) is Λ ≤ 350 μm or Λ ≥ 650 μm. By means of controlling the ink dot period of the ink dots (20) to be Λ ≤ 350 μm or Λ ≥ 650 μm, an additional attenuation loss caused by the presence of the ink-jet identifier (2) can be reduced, such that the occurrence of a grating effect in the ring-sprayed optical fiber can be reduced or even prevented to the greatest possible extent, thereby guaranteeing the transmission performance within a transmission wavelength range.

Description

A kind of spray ring optical fiber and optical cable

Technical field

The present application relates to the field of optical fiber technology, and in particular to a spray ring optical fiber and an optical cable.

Background technique

Fiber grating is a passive filtering optical device formed by axial periodic modulation of the refractive index of the fiber core. Fiber gratings are generally manufactured by UV writing methods and mechanical stress methods. Among them, the most widely used method is the ultraviolet writing method. This method uses the photosensitivity of the fiber core material silica (the refractive index of the fiber core is permanently changed by incident photons from the outside) to form a spatial phase grating in the fiber core. , so that the optical fiber has filtering characteristics. The mechanical stress method applies radial inward stress to the optical fiber through various forms of mechanical external forces outside the optical fiber, thereby inducing the grating effect and forming a fiber grating.

In some related technologies, a fiber grating and a manufacturing method thereof are disclosed, which are characterized by providing hard inlays evenly spaced along the axial direction between the fiber coating and the colored coating. , causing the optical fiber core to be subject to periodic internal stress, causing periodic changes in the core density, thereby producing a grating effect and forming a fiber grating.

In the communication optical cable industry, a technology called fiber spray ring has been widely used. This spray ring technology is used to form a color ring on the optical fiber, so that different optical fibers in the same casing unit can be identified and distinguished. Especially when a large number of optical fibers are accommodated in the same casing unit, for example, 24 cores, 36 cores or even 48 cores are accommodated in the same casing unit.

However, when this kind of color ring is attached to the optical fiber, because the color ring also has a certain thickness, the color ring is similar to the above-mentioned hard inlay, which may cause the fiber core to be subject to radial inward periodic stress. This causes periodic changes in the fiber core density, which in turn produces a grating effect. This grating effect will increase the attenuation of the optical fiber and affect the transmission performance of the optical fiber itself.

Contents of the invention

Embodiments of the present application provide a spray-ring optical fiber and an optical cable, which can reduce or even avoid the grating effect in the spray-ring optical fiber as much as possible, ensuring transmission performance within the transmission wavelength range.

In a first aspect, a spray ring optical fiber is provided. The spray ring optical fiber is a single-mode optical fiber, which includes a natural color optical fiber, and an inkjet mark provided on the outer wall of the natural color optical fiber;

The inkjet mark includes a plurality of ink dots distributed periodically along the axis of the natural optical fiber;

The ink dot period Λ of the ink dot is ≤350 μm or ≥650 μm.

In some embodiments, the ink dot period Λ is ≤300 μm or ≥700 μm.

In some embodiments, the distance L ₁ between two adjacent inkjet marks ranges from 35 to 500 mm.

In some embodiments, the number of ink dots included in the inkjet mark is 5 to 20.

In some embodiments, the transmission wavelength range of the single-mode optical fiber is 1200nm ~ 1650nm.

In some embodiments, the ink dot period Λ is the sum of the length of the ink dot along the axis of the natural optical fiber and the distance between two adjacent ink dots.

In some embodiments, the following formula is used to calculate the ink dot period Λ:

Λ＝(D ₁ -d ₁ )/[N(m ₁ -1)]+(D ₂ -d ₂ )/[N(m ₂ -1)]+...+(D _i -d _i )/ [N(m _i -1)]+...+(D _N -d _N )/[N(m _N -1)]

Wherein, N is the number of inkjet marks on a segment of the spray ring optical fiber, N≥2;

D _i is the length of the i-th inkjet mark along the axis of the natural optical fiber, i=1,...,N;

d _i is the length of any ink dot in the i-th inkjet mark along the axis of the natural optical fiber;

m _i is the number of ink dots contained in the i-th inkjet mark.

In some embodiments, the spray ring optical fiber further includes a colored coating layer, the colored coating layer covers the outer wall of the natural color optical fiber, and the inkjet mark is located between the natural color optical fiber and the colored coating layer between;

And/or, the natural optical fiber includes a core, a cladding and an optical fiber coating layer arranged sequentially from inside to outside along the warp direction;

And/or, the inkjet mark is a single ring, or includes at least two single rings spaced apart along the axis direction of the natural optical fiber;

And/or, the inkjet mark has an opening in a cross-section perpendicular to the axial direction of the natural optical fiber.

In a second aspect, a spray ring optical fiber is provided, which includes a natural color optical fiber and an inkjet mark provided on the outer wall of the natural color optical fiber;

The ink dot period Λ of the ink dot is configured such that the additional attenuation loss caused by the presence of the inkjet mark within the transmission wavelength range of the spray ring optical fiber is no higher than a preset value.

In a third aspect, an optical cable is provided, which includes the spray ring optical fiber as described in any one of the above.

The beneficial effects brought by the technical solution provided by this application include:

The embodiment of the present application provides a spray ring optical fiber and optical cable. By controlling the ink dot period Λ ≤ 350 μm or ≥ 650 μm, the additional attenuation loss caused by the presence of the inkjet mark can be reduced, thereby reducing or even minimizing the loss. Avoid the grating effect in the spray ring fiber as much as possible to ensure the transmission performance within the transmission wavelength range.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without exerting creative efforts.

Figure 1 is a schematic diagram of the spray ring fiber attenuation generation provided by the embodiment of the present application;

Figure 2 is a schematic diagram of the manufacturing of the spray ring optical fiber provided by the embodiment of the present application;

Figure 3 is a schematic cross-sectional view of the spray ring optical fiber provided by the embodiment of the present application;

Figure 4 is an enlarged view of the inkjet mark in the spray ring optical fiber provided by the embodiment of the present application;

Figure 5 is a schematic diagram of the spray ring optical fiber provided by the embodiment of the present application (single ring);

Figure 6 is a schematic diagram of the spray ring optical fiber (double ring) provided by the embodiment of the present application;

Figure 7 is the additional attenuation spectrum of the spray ring optical fiber with an ink dot period of 250 μm provided by the embodiment of the present application;

Figure 8 is the additional attenuation spectrum of the spray ring optical fiber with an ink dot period of 350 μm provided by the embodiment of the present application;

Figure 9 is the additional attenuation spectrum of the spray ring optical fiber with an ink dot period of 450 μm provided by the embodiment of the present application;

Figure 10 is the additional attenuation spectrum of the spray ring optical fiber with an ink dot period of 550 μm provided by the embodiment of the present application;

Figure 11 is an additional attenuation spectrum of the spray ring optical fiber with an ink dot period of 650 μm provided by the embodiment of the present application.

In the picture: 1. Natural color optical fiber; 10. Core; 11. Cladding; 12. Optical fiber coating; 2. Inkjet marking; 20. Ink dots; 3. Colored coating; 4. Pay-off unit; 5 , Inkjet coding equipment; 6. Colored ink coating mold; 7. Colored ink curing oven; 8. Take-up unit.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments These are part of the embodiments of this application, but not all of them. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of this application.

During the research on spray-ring optical fibers, the applicant inadvertently conducted attenuation spectrum tests on natural optical fibers and spray-ring optical fibers. When comparing the additional attenuation spectra of the two, it was found that within the transmission wavelength range of the optical fiber, certain wavebands appeared. The phenomenon of increased attenuation.

As for the phenomenon of attenuation found in spray-ring optical fibers, the applicant then read a large number of documents and books, but failed to find anyone in this field or industry mentioning this phenomenon, let alone explaining this phenomenon and how to avoid it. an attenuation phenomenon.

Subsequently, the applicant conducted more in-depth research on the above phenomenon, combined with the principle of fiber grating, and clarified the cause of the above attenuation. Refer to Figure 1 for details. The ink dots 20 located under the colored coating layer 3 are due to the existence of A certain thickness, coupled with the fact that the ink dots 20 are periodically distributed, cause the optical fiber core to be subject to radially inward uneven periodic stress, which in turn causes changes in the refractive index of the optical fiber core, thereby triggering the grating effect and affecting the Transmission attenuation of spray ring fiber.

After finding the cause of the increase in attenuation, the applicant aimed its research at how to reduce or even avoid the impact of this increase in attenuation on the transmission performance of the spray ring optical fiber.

Since the spray ring on the spray ring optical fiber is used to identify and distinguish different optical fibers in the same casing unit, in order to avoid the increase in attenuation caused by the spray ring, the simplest solution is to not use the spray ring directly and replace it with Another way to identify and distinguish. However, this solution still fails to fundamentally solve the above problem, that is, how to use a spray ring to identify and distinguish different optical fibers in the same casing unit, and at the same time It can also reduce or even avoid the impact of the increased attenuation caused by the spray ring on the transmission performance of the spray ring optical fiber.

After a lot of research, the applicant found that in the spray ring fiber optic technology, among the process parameters related to the spray ring such as ink dot period, the number of ink dots in a single ring, the number of rings, the spacing, etc., the applicant found that the ink dot period It has an impact on whether the grating effect will appear within the transmission band of the spray ring optical fiber.

That is to say, the impact of the increased attenuation caused by the spray ring on the transmission performance of the spray ring optical fiber can be reduced or even avoided by controlling the ink dot period.

In view of this, referring to Figures 2, 3, 4, 5 and 6, embodiments of the present application provide a spray ring optical fiber. The spray ring optical fiber is a single-mode optical fiber, which includes a natural optical fiber 1 and a device. Inkjet mark 2 on the outer wall of the natural optical fiber 1; the natural optical fiber 1 usually includes a core 10, a cladding 11 and an optical fiber coating 12 arranged sequentially from the inside to the outside along the meridional direction; outside the optical fiber coating 12, there are also A layer of colored coating layer 3 will be coated, so that the inkjet mark 2 is located between the natural color optical fiber 1 and the colored coating layer 3; as can be seen from Figure 3, the inkjet mark 2 is in the direction perpendicular to the axis of the natural color optical fiber 1 The shape of the cross section has an opening, that is to say, after being covered by the colored coating layer 3, the inkjet mark 2 becomes an arc shape, like an open ring. Of course, it may also be covered into a closed ring, due to the inkjet mark 2. Mark 2 is only used for marking. During inkjet printing, as shown in Figure 2, it will be sprayed on one side, so it is usually a split ring as shown in Figure 3.

Among them, the inkjet mark 2 includes a number of ink dots 20 periodically distributed along the axial direction of the natural color optical fiber 1. The shape of the ink dots 20 is generally an approximately elliptical shape spread on the circumferential surface of the optical fiber, and has a certain thickness; its color is generally Black or a color that contrasts sharply with the colored coating layer 3 and the optical fiber coating layer 12 is visible to the naked eye on the surface of the optical fiber; and the ink dot period Λ of the ink dot 20 is ≤ 350 μm or ≥ 650 μm.

As shown in Figure 2, the natural color optical fiber 1 is paid out through the pay-out unit 4 on the coloring equipment, passes through the inkjet coding equipment 5, the coloring ink coating mold 6, the coloring ink curing furnace 7, and finally passes through the take-up unit 8 on the coloring equipment. Collect it on a special tray to form a spray ring fiber.

Among them, the inkjet mark 2 in the inkjet ring optical fiber is mainly formed by the inkjet coding equipment 5 . The inkjet coding equipment 5 dissolves extremely fine carbon black particles in an organic solvent, and uses a crystal oscillator element to disperse them into small charged droplets with a diameter of microns. Finally, the small carbon black droplets are controlled by a deflection plate with an electric field. The falling trajectory makes it fall on the surface of the natural optical fiber 1 at certain intervals along the axial direction of the optical fiber.

In actual production, by linking the inkjet coding equipment 5 with the coloring equipment and matching the falling interval of the carbon black droplets with the linear speed of the optical fiber coloring production, the morphological characteristics of the ink dots 20 and the inkjet marks 2 in the spray ring optical fiber can be controlled.

Therefore, by controlling the falling interval of the ink dots 20 and the linear speed of the optical fiber coloring production, the ink dot period Λ of the ink dots 20 can be controlled to reduce the additional attenuation loss caused by the presence of the inkjet mark, and ultimately reduce or even eliminate it. Avoid the grating effect in the spray ring fiber as much as possible to ensure the transmission performance within the transmission wavelength range.

As shown in Figure 5, the inkjet mark 2 can be a single ring. As shown in Figure 6, the inkjet mark 2 can also be a multi-ring, that is, it includes at least two single rings spaced apart along the axial direction of the natural color optical fiber 1.

The shapes of spray-ring optical fibers with other ring numbers can be referred to Figure 5 and Figure 6 and so on.

The morphological and structural characteristics of a single inkjet mark in the spray ring optical fiber are shown in Figure 4. An inkjet mark 2 in the large dotted box is composed of 8 single ink dots 20. The length of an ink dot 20 in the small dotted box along the axis of the natural color optical fiber 1 is the same as the length between two adjacent ink dots 20. The spacing together constitutes an ink dot period Λ.

According to the long period fiber grating theory, there is the following first formula:

λ _n =(n _core ⁽⁰¹⁾ -n _clad ⁽ⁿ⁾ )*Λ ₀

Among them, λ _n is the wavelength of light coupled from the fundamental mode to the n-order cladding mode, that is, the wavelength affected by the grating effect; n _core ⁽⁰¹⁾ and n _clad ⁽ⁿ⁾ are the core fundamental mode and n-order cladding mode respectively. The refractive index of the mode, Λ ₀ is the grating period.

When the ink dot period Λ is used to replace the grating period Λ ₀ in the above first formula, and combined with the refractive index of the fiber core and cladding, the above first formula can be used to calculate the theoretical value of the transmission wavelength affected by different ink dot periods.

Through further experiments, the applicant analyzed the impact of different ink dot periods on the attenuation spectrum of the wavelength of 1200nm to 1650nm of ordinary single-mode optical fiber. It was found that when the ink dot period is less than or equal to 300 μm or greater than or equal to 700 μm, it will not have a significant impact on the attenuation of the wavelength of 1200nm to 1650nm. When the ink dot period is between 300 μm and 700 μm, it will cause a certain wavelength in the range of 1200nm to 1650nm. The phenomenon of increased attenuation occurs in some wavebands, and the specific affected wavebands are directly related to the ink dot period, which has a negative impact on the transmission performance of the optical fiber.

In actual manufacturing, the inkjet coding equipment 5 has limited accuracy in controlling the falling of small carbon black droplets, and the measured value of the ink dot period Λ will fluctuate within a certain range. Therefore, using the above L ₂ and L ₃ to calculate the ink dot period Λ will There is a certain error. In order to reduce the error as much as possible, the average ink dot period is used as the ink dot period in the calculation, that is, the average of multiple ink dot periods is taken.

The specific method is: first, strip the optical cable from any part of the optical cable, expose any section of optical fiber, take a section of spray ring optical fiber containing multiple consecutive inkjet marks 2, and clean its surface. Then the first inkjet mark 2 is placed under a high-precision optical microscope, and the length d of the inkjet mark and the number of ink dots m are measured; and by analogy, the length d and the number of ink dots m of all inkjet marks are measured. Finally, the following second formula is used to calculate the ink dot period Λ:

Among them, N is the number of inkjet marks 2 on the selected section of spray ring optical fiber, N≥2;

d _i is the length of the i-th inkjet mark 2 along the axis of the natural fiber 1, i=1,...,N;

d _i is the length of any ink dot 20 in the i-th inkjet mark 2 along the axis of the natural color optical fiber 1;

m _i is the number of ink dots 20 included in the i-th inkjet mark 2.

According to the first formula, calculating the critical dot period for the grating effect in conventional single-mode optical fiber in the transmission window range of 1200nm to 1650nm requires knowing the difference in refractive index between the core fundamental mode and the n-order cladding mode. However, considering that different manufacturers , the difference is difficult to obtain for optical fibers produced by different processes, and there are certain differences in this difference at different wavelengths. Therefore, the applicant used relevant literature ("Design and Manufacturing of Optical Fibers and Cables" ("Design and Manufacturing of Optical Fibers and Cables") in the actual test Fourth Edition), written by Chen Bingyan, Zhejiang University Press, 2020.6, P167, Figure 1-5, refractive index profile diagram of full-wave optical fiber) Typical refractive index difference between the core and cladding of G.652D single-mode fiber The value is 0.48% for rough calculation, which is used to guide the setting of the critical value of the average ink dot period in the experiment.

According to calculations, the theoretical ink dot period for the grating effect to appear at 1200nm is 250μm, and the theoretical ink dot period for the grating effect to appear at 1650nm is 344μm. Therefore, a spray ring experiment was designed for a conventional G.652D optical fiber according to the following parameters:

样品编号Sample serial number	平均墨点周期Average dot period	墨点数量Number of ink dots	间距spacing
1#1#		250μm250μm	10～1110～11	4.8～5.3mm4.8～5.3mm
2#2#		350μm350μm	10～1110～11	4.8～5.3mm4.8～5.3mm
3#3#		450μm450μm	10～1110～11	4.8～5.3mm4.8～5.3mm

4#4#		550μm550μm	10～1110～11	4.8～5.3mm4.8～5.3mm
5#5#		650μm650μm	10～1110～11	4.8～5.3mm4.8～5.3mm

Subsequently, the 1#~5# spray ring optical fiber samples and the natural fiber samples before the spray ring were sampled to test the attenuation spectrum, and the attenuation loss values were subtracted to obtain the additional attenuation loss caused by the presence of the inkjet mark, and then obtained The additional attenuation spectra of 1#~5# spray ring optical fibers are shown in Figure 7~Figure 11 (the value of the ordinate × 10 ^-2 ). It can be seen that:

When the average ink dot period is 250μm, there is no obvious additional loss in the wavelength range of 1200~1650nm;

When the average ink dot period is 350μm, there is an obvious additional loss peak at the wavelength of 1260nm;

When the average ink dot period is 450μm, there is an obvious additional loss peak at the wavelength of 1440nm;

When the average ink dot period is 550μm, there is an obvious additional loss peak at the wavelength of 1590nm;

When the average ink dot period is 650μm, there is no obvious additional loss in the wavelength range of 1200~1650nm;

It can be seen that under the above experimental conditions, the critical average ink dot period for the grating effect to appear is about 350 μm and 650 μm. Taking into account the experimental accuracy and the difference in the refractive index difference between the core and cladding of natural optical fibers produced by different manufacturers and processes, this critical value should be appropriately extrapolated to cover the situation of mainstream single-mode optical fibers, so the preferred ink dot period The critical values are 300μm and 700μm.

In actual manufacturing, the distance L ₁ between two adjacent inkjet marks 2 can be adjusted as needed, but is generally controlled within 35 to 500 mm. When the spacing L ₁ is less than 35mm, the inkjet marks 2 are too dense in the axial direction of the optical fiber. Even if no grating effect occurs, the ink dots 20 located under the colored coating layer 3 may cause dense micro-bending of the optical fiber, thereby increasing the length of the optical fiber. Transmission loss in the wavelength window (near the 1650nm side); when the spacing _L1 exceeds 500mm, it may affect the splicing operation during optical cable construction. This is because during the construction of optical cables, the length generally used to connect optical fibers is 0.5 to 1m. If the distance _L1 exceeds 500mm, it means that the inkjet mark 2 is sparser on the surface of the optical fiber, and it may be difficult to identify the inkjet ring optical fiber during splicing.

In actual manufacturing, the number of ink dots 20 can be adjusted as needed, but is generally controlled within the range of 5 to 20. When the number of ink dots 20 in a single inkjet mark 2 is less than 5, the length of the inkjet mark 2 is too short, which will affect the legibility of the inkjet mark 2 on the inkjet ring optical fiber. Therefore, generally the number of ink dots 20 is generally greater than 5. when the number of ink dots 20 is 10 to 15, the inkjet mark 2 can have better recognition; when the number of ink dots 20 in a single inkjet mark 2 exceeds 20, the ink dots 20 in the axial direction of the optical fiber The number may be too dense, and the ink dots 20 located under the colored coating layer 3 may cause dense micro-bending of the optical fiber, thereby increasing the transmission loss in the long wavelength window of the optical fiber (near the 1650nm side).

This application also provides a spray ring optical fiber, which includes a natural color optical fiber 1 and an inkjet mark 2 provided on the outer wall of the natural color optical fiber 1; the inkjet mark 2 includes a number of ink dots periodically spaced along the axis of the natural color optical fiber 1. 20; The ink dot period Λ of the ink dot 20 is configured such that the additional attenuation loss caused by the presence of the inkjet mark within the transmission wavelength range of the spray ring optical fiber is not higher than the preset value. It can be seen that this application can reduce or even avoid the grating effect in the spray ring fiber as much as possible, ensuring the transmission performance within the transmission wavelength range.

As an example, in this embodiment, the spray ring optical fiber can be a single-mode optical fiber. At this time, its dot period Λ≤350 μm or ≥650 μm. The transmission wavelength range of the single-mode optical fiber is 1200 nm to 1650 nm. For the preset value , can be set according to the actual transmission performance requirements of the optical fiber. The purpose is to determine whether there is obvious additional attenuation loss caused by the presence of inkjet markings to meet the transmission performance requirements, as shown in Figures 7 to 11. That way, for example, as an example, it can be seen from the above-mentioned figures 7 to 11 that the default value is set to 0.2dB/km. If the additional attenuation loss caused by the presence of the inkjet mark is within the entire transmission wavelength range, If it does not exceed 0.2dB/km, it means there is no obvious additional loss. Otherwise, there will be obvious additional loss.

As an example, in this embodiment, the spray ring optical fiber can also be other types of optical fibers, such as multi-mode optical fibers. At this time, the dot period Λ can be obtained by repeating the above-mentioned acquisition principle of the ink dot period of single-mode optical fiber. According to the above Calculate and obtain the ink dot period of single-mode fiber, and we will not do detailed calculations here.

This application also provides an optical cable, which includes the spray ring optical fiber provided in the above embodiment.

In the description of this application, it should be noted that the orientation or positional relationship indicated by terms such as "upper" and "lower" is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing this application and simplifying the description. It is not intended to indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be construed as a limitation on the present application. Unless otherwise clearly stated and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, It can also be an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be an internal connection between two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

It should be noted that in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply There is no such actual relationship or sequence between these entities or operations. Furthermore, the terms "comprises," "comprises," or any other variation thereof are intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus that includes a list of elements includes not only those elements, but also those not expressly listed other elements, or elements inherent to the process, method, article or equipment. Without further limitation, an element defined by the statement "comprises a..." does not exclude the presence of additional identical elements in a process, method, article, or apparatus that includes the stated element.

The above descriptions are only specific embodiments of the present application, enabling those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be practiced in other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

A spray ring optical fiber, characterized in that the spray ring optical fiber is a single-mode optical fiber, which includes a natural color optical fiber (1), and an inkjet mark (2) provided on the outer wall of the natural color optical fiber (1);

The inkjet mark (2) includes a number of ink dots (20) periodically distributed along the axial direction of the natural optical fiber (1);

The ink dot period Λ of the ink dot (20) is ≤350 μm or ≥650 μm.
The spray ring optical fiber according to claim 1, characterized in that:

The ink dot period Λ is ≤300 μm or ≥700 μm.
The spray ring optical fiber according to claim 1, characterized in that:

The distance L 1 between two adjacent inkjet marks (2) ranges from 35 to 500 mm.
The spray ring optical fiber according to claim 1, characterized in that:

The number of ink dots (20) contained in the inkjet mark (2) is 5 to 20.
The spray ring optical fiber according to claim 1, characterized in that:

The transmission wavelength range of the single-mode optical fiber is 1200nm ~ 1650nm.
The spray ring optical fiber according to claim 1, characterized in that:

The ink dot period Λ is the sum of the length of the ink dot (20) along the axial direction of the natural optical fiber (1) and the distance between two adjacent ink dots (20).
The spray ring optical fiber according to claim 1, characterized in that the following formula is used to calculate the ink dot period Λ:

Λ＝(D 1 -d 1 )/[N(m 1 -1)]+(D 2 -d 2 )/[N(m 2 -1)]+...+(D i -d i )/ [N(m i -1)]+...+(D N -d N )/[N(m N -1)]

Wherein, N is the number of inkjet marks (2) on a section of the spray ring optical fiber, N≥2;

D i is the length of the i-th inkjet mark (2) along the axis of the natural optical fiber (1), i=1,...,N;

d i is the length of any ink dot (20) in the i-th inkjet mark (2) along the axial direction of the natural color optical fiber (1);

m i is the number of ink dots (20) included in the i-th inkjet mark (2).
The spray ring optical fiber according to claim 1, characterized in that:

The spray ring optical fiber also includes a colored coating layer (3), the colored coating layer (3) covers the outer wall of the natural color optical fiber (1), and the inkjet mark (2) is located on the natural color optical fiber. Between (1) and the colored coating layer (3);

And/or, the natural optical fiber (1) includes a core (10), a cladding (11) and an optical fiber coating (12) arranged sequentially from inside to outside along the warp direction;

And/or, the inkjet mark (2) is a single ring, or includes at least two single rings spaced apart along the axial direction of the natural optical fiber (1);

And/or, the inkjet mark (2) has an opening in a cross-section perpendicular to the axial direction of the natural optical fiber (1).
A spray ring optical fiber, characterized in that it includes a natural color optical fiber (1), and an inkjet mark (2) provided on the outer wall of the natural color optical fiber (1);

The inkjet mark (2) includes a number of ink dots (20) periodically distributed along the axial direction of the natural optical fiber (1);

The ink dot period Λ of the ink dot (20) is configured such that within the transmission wavelength range of the spray ring optical fiber, the additional attenuation loss caused by the presence of the inkjet mark (2) is no greater than default value.
An optical cable, characterized in that it includes the spray ring optical fiber according to any one of claims 1 to 9.