Low-reflection-loss special optical fiber and preparation method thereof

Abstract

The invention discloses a low-reflection-loss special optical fiber and a preparation method thereof, the special optical fiber comprises a fiber core, a cladding and a coating layer which are sequentially arranged from inside to outside, a heat conduction layer is arranged on the peripheral side of the coating layer, the heat conduction layer comprises heat conduction wires wound on the peripheral side of the coating layer, and a gap is reserved between every two adjacent turns of heat conduction wires to form a heat conduction space; at least one reinforcing strip is arranged on the peripheral side of the heat conduction layer, extends in the length direction of the fiber core and is fixedly connected with the heat conduction wires. The low-reflection-loss special optical fiber provided by the invention can quickly exchange heat with the ambient environment when the ambient temperature changes, so that local tiny bending caused by non-uniform thermal expansion and cold contraction due to different internal and external temperatures of the optical fiber main body is avoided, and the reflection loss is further avoided.

Description

Technical Field

[0001] The invention relates to the field of optical fibers, in particular to a low reflection loss special optical fiber and a preparation method thereof. Background Art

[0002] Optical fiber is the abbreviation of optical fiber. It is a fiber made of glass or plastic. It transmits light through the principle of total reflection of light, thereby realizing the function of transmitting information. In practical applications, it is difficult for optical fiber to transmit light truly losslessly. Many factors will cause light loss and attenuation in the optical fiber. For example, when there is a local slight bend in the optical fiber, the incident angle of the light at the junction of the core and the cladding will change, which will lead to the failure to meet the total reflection condition, causing part of the light to scatter through the cladding and coating layer, resulting in light loss. These losses caused by the inability to maintain total reflection can be called reflection loss. There are many situations that can cause local slight bends in optical fibers, including limited processing accuracy or complex application environment. One of the factors is the change in the temperature of the environment in which the optical fiber is located, because optical fibers usually have a protective layer to increase the strength of the optical fiber, and the protective layer causes the heat transfer speed between the inside and the outside to be slow, resulting in different thermal expansion and contraction trends inside and outside the optical fiber due to different temperatures, which in turn causes local deformation of the optical fiber and reflection loss. Summary of the invention

[0003] In order to address the deficiencies in the prior art, the present invention provides a low reflection loss special optical fiber and a preparation method thereof, which can quickly exchange heat with the surrounding environment when the ambient temperature changes, thereby avoiding local micro-bending caused by uneven thermal expansion and contraction of the optical fiber body due to different internal and external temperatures, thereby avoiding reflection loss.

[0004] In order to achieve the above object, the specific scheme adopted by the present invention is: A low reflection loss special optical fiber comprises a core, a cladding and a coating layer which are sequentially arranged from the inside to the outside, a heat conducting layer is arranged on the circumference of the coating layer, the heat conducting layer comprises a heat conducting wire wound on the circumference of the coating layer, and a gap is left between two adjacent turns of the heat conducting wire to form a heat conducting space, at least one reinforcement bar is arranged on the circumference of the heat conducting layer, the reinforcement bar extends along the length direction of the core, and the reinforcement bar is fixedly connected to the heat conducting wire.

[0005] Preferably, the cross section of the heat conductive wire is polygonal, and when the heat conductive wire is attached to the coating layer, there is surface contact between the heat conductive wire and the coating layer.

[0006] Preferably, the cross-section of the heat conductive wire is a regular hexagon.

[0007] Preferably, the heat conductive wire comprises a plurality of positive helical segments and a plurality of reverse helical segments, the positive helical segments and the reverse helical segments are both wound on the coating layer, and the positive helical segments and the reverse helical segments are staggered.

[0008] Preferably, adjacent positive helical segments and negative helical segments are connected via a transition segment, and the transition segment extends along the length direction of the fiber core and is attached to the coating layer.

[0009] Preferably, the transition section is fixed on the coating layer by a ring sleeved on the coating layer.

[0010] Preferably, the collar extrude the reinforcement strip to form a plurality of recessed portions on the reinforcement strip, and the recessed portions are located between adjacent positive helical segments and negative helical segments.

[0011] Preferably, the reinforcement strips are provided in plurality, and the plurality of reinforcement strips are evenly distributed along the circumferential direction of the fiber core.

[0012] Preferably, the reinforcement strip is provided with a protrusion extending toward the circumferential side, and the width of the protrusion is smaller than the width of the reinforcement strip.

[0013] Preferably, the method for preparing the optical fiber comprises the following steps: preparing an optical fiber body consisting of the core, the cladding and the coating layer; Winding the heat-conducting wire on the optical fiber body, and leaving a gap between two adjacent turns of the heat-conducting wire to form the heat-conducting space; The reinforcing strip is fixedly connected to the heat conducting wire.

[0014] When the special optical fiber of the present invention is used, the core, cladding and coating constitute the optical fiber body, and the heat-conducting layer serves as a heat exchange medium between the optical fiber body and the surrounding environment. When the temperature of the surrounding environment changes, the temperature of the optical fiber body and the surrounding environment can be quickly balanced through the heat-conducting layer to ensure that the temperature of the optical fiber body can match the temperature of the surrounding environment, thereby avoiding the uneven thermal expansion and contraction of the optical fiber body due to the different internal and external temperatures, resulting in local micro-bending, thereby avoiding the increase of reflection loss due to the appearance of local micro-bending, achieving the characteristic of low reflection loss, and ensuring the stability of information transmission. Because the heat-conducting wire is wound on the optical fiber body, the heat exchange between the optical fiber body and the surrounding environment can be achieved at different positions and directions of the optical fiber body, ensuring the heat exchange effect. And there is a gap between two adjacent turns of the heat-conducting wire, which can form a heat-conducting space on the one hand, thereby expanding the heat exchange area of ​​the heat-conducting wire and improving the heat exchange efficiency. On the other hand, it can also avoid the heat-conducting layer completely covering the optical fiber body, resulting in an increase in the minimum bending radius of the optical fiber body, thereby ensuring the flexibility of the optical fiber and being easy to lay when in use. In addition, by setting up reinforcement strips, various positions of the thermal wire can be connected, thereby improving the stability of the thermal wire shape and preventing the thermal wire from shifting due to twisting, thereby ensuring that the thermal wire can smoothly achieve heat exchange between the optical fiber body and the surrounding environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 is a schematic cross-sectional view of the special optical fiber of the present invention; Figure 2 It is a schematic diagram of the structure of the thermal wire; Figure 3 is a schematic cross-sectional view of the thermal wire; Figure 4 It is a schematic diagram of the structure of the ring.

[0017] Figure numerals: 1-fiber core, 2-cladding, 3-coating layer, 4-heat conducting layer, 5-reinforcement strip, 6-protrusion, 7-ring, 8-heat conducting space, 9-heat conducting wire, 10-positive helical section, 11-reverse helical section, 12-transition section. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] like Figure 1 As shown, a low reflection loss special optical fiber includes a core 1, a cladding 2 and a coating layer 3 arranged in sequence from the inside to the outside, a heat-conducting layer 4 is arranged on the circumferential side of the coating layer 3, the heat-conducting layer 4 includes a heat-conducting wire 9 wound on the circumferential side of the coating layer 3, and a gap is left between two adjacent turns of the heat-conducting wire 9 to form a heat-conducting space 8, at least one reinforcement strip 5 is arranged on the circumferential side of the heat-conducting layer 4, the reinforcement strip 5 extends along the length direction of the core 1, and the reinforcement strip 5 is fixedly connected to the heat-conducting wire 9.

[0020] When the special optical fiber of the present invention is used, the core 1, the cladding 2 and the coating 3 form the optical fiber body, and the heat-conducting layer 4 is used as the heat exchange medium between the optical fiber body and the surrounding environment. When the temperature of the surrounding environment changes, the temperature of the optical fiber body and the surrounding environment can be quickly balanced through the heat-conducting layer 4 to ensure that the temperature of the optical fiber body can match the temperature of the surrounding environment, thereby avoiding the uneven thermal expansion and contraction of the optical fiber body due to the different internal and external temperatures, resulting in local micro-bending, thereby avoiding the increase of reflection loss due to the appearance of local micro-bending, achieving the characteristics of low reflection loss, and ensuring the stability of information transmission. Because the heat-conducting wire 9 is wound on the optical fiber body, the heat exchange between the optical fiber body and the surrounding environment can be achieved at different positions and directions of the optical fiber body, ensuring the heat exchange effect. And there is a gap between the two adjacent turns of the heat-conducting wire 9, which can form a heat-conducting space 8 on the one hand, thereby expanding the heat exchange area of ​​the heat-conducting wire 9 and improving the heat exchange efficiency. On the other hand, it can also avoid the heat-conducting layer 4 completely covering the optical fiber body, resulting in an increase in the minimum bending radius of the optical fiber body, thereby ensuring the flexibility of the optical fiber and easy to lay when in use. In addition, by providing the reinforcing strip 5, the various positions of the thermal wire 9 can be connected, thereby improving the stability of the shape of the thermal wire 9 and preventing the thermal wire 9 from shifting due to twisting, thereby ensuring that the thermal wire 9 can smoothly achieve heat exchange between the optical fiber body and the surrounding environment.

[0021] In order to further improve the heat transfer efficiency of the heat conductive wire 9, the cross section of the heat conductive wire 9 is polygonal. When the heat conductive wire 9 is attached to the coating layer 3, the heat conductive wire 9 and the coating layer 3 are in surface contact. By making the heat conductive wire 9 and the coating layer 3 in surface contact, the heat transfer speed between the optical fiber body and the heat conductive wire 9 can be accelerated, thereby achieving the effect of improving the heat transfer efficiency of the heat conductive wire 9. The specific shape of the cross section of the heat conductive wire 9 can be determined according to actual needs, for example, Figure 3As shown, in one embodiment of the present invention, the cross-section of the heat-conducting wire 9 is a regular hexagon, which makes it easier to attach the heat-conducting wire 9 to the coating layer 3 while ensuring that the heat-conducting wire 9 can be in surface contact with the optical fiber body.

[0022] like Figure 2 As shown, the specific structure of the heat conductive wire 9 is as follows: the heat conductive wire 9 includes a plurality of positive helical segments 10 and a plurality of reverse helical segments 11, and both the positive helical segments 10 and the reverse helical segments 11 are wound on the coating layer 3, and the positive helical segments 10 and the reverse helical segments 11 are staggered. By decomposing the heat conductive wire 9 into a plurality of positive helical segments 10 and a plurality of reverse helical segments 11, it is possible to avoid the heat conductive wire 9 as a whole completely turning into a spring structure, which in turn causes the optical fiber to be unable to be bent smoothly due to the rebound of the heat conductive wire 9 when the optical fiber needs to be bent, thereby fully ensuring the flexibility of the optical fiber when in use.

[0023] Furthermore, the adjacent positive helical segments 10 and reverse helical segments 11 are connected by a transition segment 12, which extends along the length direction of the fiber core 1 and is attached to the coating layer 3. By providing the transition segment 12, the adjacent positive helical segments 10 and reverse helical segments 11 can be separated to avoid mutual influence that makes it difficult to wind the heat conductive wire 9 onto the optical fiber body. At the same time, attaching the transition segment 12 to the optical fiber body can ensure that the adjacent positive helical segments 10 and reverse helical segments 11 also have good thermal conductivity.

[0024] The heat conducting wire 9 is fixed on the optical fiber body in the following manner: the transition section 12 is fixed on the coating layer 3 by a sleeve ring 7 sleeved on the coating layer 3, and the sleeve ring 7 has a structure as shown in FIG. Figure 4 As shown. By fixing the transition section 12 on the coating 3, it is not necessary to connect the positive helical section 10 and the reverse helical section 11 to the coating 3. Then, when the heat-conducting wire 9 is wound on the optical fiber body, the distance between the two adjacent turns in the positive helical section 10 and the reverse helical section 11 can be adjusted as needed. When the optical fiber is partially susceptible to impact, the distance between the two adjacent turns in the positive helical section 10 and the reverse helical section 11 can be reduced, so that the heat-conducting wire 9 is used to form protection on the peripheral side of the optical fiber body, and the optical fiber body, especially the core 1 and the cladding 2, is protected to prevent the optical fiber body from cracking or even breaking due to impact, thereby ensuring the stability of information transmission. It should also be noted that when reducing the distance between the two adjacent turns in the positive helical section 10 and the reverse helical section 11, it is still necessary to ensure that a heat-conducting space 8 can be formed between the two adjacent turns. In addition, the transition section 12 is fixed to the coating 3 using the sleeve ring 7, and the fixing effect is better. Even if the transition section 12 is offset, it will not be completely separated from the coating 3.

[0025] Furthermore, the collar 7 squeezes the reinforcing strip 5 to form a plurality of recessed portions, and the recessed portions are located between adjacent positive helical segments 10 and reverse helical segments 11. The collar 7 is used to form recessed portions on the reinforcing strip 5, and the recessed portions are located between adjacent positive helical segments 10 and reverse helical segments 11. The collar 7 can be used to limit the adjacent positive helical segments 10 and reverse helical segments 11, ensuring that the positive helical segments 10 and reverse helical segments 11 are distributed uniformly enough, thereby ensuring the heat exchange efficiency of the heat conductive wire 9.

[0026] In order to enhance the effect of the reinforcement strip 5 in reinforcing the heat conducting wire 9 , a plurality of reinforcement strips 5 are provided, and the plurality of reinforcement strips 5 are evenly distributed along the circumferential direction of the fiber core 1 .

[0027] Furthermore, the reinforcing strip 5 is provided with a protrusion 6 extending toward the circumferential side, and the width of the protrusion 6 is smaller than the width of the reinforcing strip 5. Through this arrangement, the reinforcing strip 5 can reduce the weight while keeping the surface area unchanged, thereby reducing the weight of the optical fiber as a whole. The reinforcing strip 5 can also be set to be the same material as the thermal conductive wire 9, so that the heat exchange efficiency between the optical fiber body and the surrounding environment can be improved by using the reinforcing strip 5 and the thermal conductive wire 9. The reinforcing strip 5 and the thermal conductive wire 9 can be fixed by bonding, and at least one turn in a positive helical segment 10 and a reverse helical segment 11 is connected to the reinforcing strip 5, and the rest of the parts can directly contact the reinforcing strip 5 to achieve heat transfer.

[0028] In one embodiment of the present invention, the optical fiber body is a conventional structure of an optical fiber, and its material and production process are not described in detail here. The heat conductive wire 9 can be made of metal, such as copper, and correspondingly, the reinforcing strip 5 is also made of copper, and the sleeve 7 can be made of PVC. The transition section 12 is pressed against the optical fiber body by heating and shrinking to fix the heat conductive wire 9.

[0029] The above-mentioned method for preparing a low reflection loss special optical fiber includes S1 to S3.

[0030] S1. Prepare an optical fiber body consisting of a core 1, a cladding 2 and a coating 3.

[0031] S2, winding the heat-conducting wire 9 on the optical fiber body, and leaving a gap between two adjacent turns of the heat-conducting wire 9 to form a heat-conducting space 8.

[0032] S3, fixing and connecting the reinforcing strip 5 and the heat conducting wire 9.

[0033] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0034] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A low reflection loss special optical fiber, comprising a core (1), a cladding (2) and a coating (3) arranged in sequence from the inside to the outside, characterized in that: A heat-conducting layer (4) is arranged on the circumferential side of the coating layer (3), the heat-conducting layer (4) comprises a heat-conducting wire (9) wound on the circumferential side of the coating layer (3), and a gap is left between two adjacent turns of the heat-conducting wire (9) to form a heat-conducting space (8), and at least one reinforcement strip (5) is arranged on the circumferential side of the heat-conducting layer (4), the reinforcement strip (5) extends along the length direction of the fiber core (1), and the reinforcement strip (5) is fixedly connected to the heat-conducting wire (9).

2. A low reflection loss special optical fiber as claimed in claim 1, characterized in that: The cross section of the heat-conducting wire (9) is polygonal, and when the heat-conducting wire (9) is attached to the coating layer (3), the heat-conducting wire (9) and the coating layer (3) are in surface contact.

3. A low reflection loss special optical fiber as claimed in claim 2, characterized in that: The cross section of the heat conducting wire (9) is a regular hexagon.

4. A low reflection loss special optical fiber as claimed in claim 1, characterized in that: The heat conductive wire (9) comprises a plurality of positive helical segments (10) and a plurality of reverse helical segments (11), wherein the positive helical segments (10) and the reverse helical segments (11) are both wound on the coating layer (3), and the positive helical segments (10) and the reverse helical segments (11) are distributed in an alternating manner.

5. A low reflection loss special optical fiber as claimed in claim 4, characterized in that: The adjacent positive helical segments (10) and reverse helical segments (11) are connected via a transition segment (12), and the transition segment (12) extends along the length direction of the fiber core (1) and is attached to the coating layer (3).

6. A low reflection loss special optical fiber as claimed in claim 5, characterized in that: The transition section (12) is fixed on the coating layer (3) by means of a sleeve ring (7) sleeved on the coating layer (3).

7. A low reflection loss special optical fiber as claimed in claim 6, characterized in that: The collar (7) presses the reinforcement strip (5) so that the reinforcement strip (5) forms a plurality of recessed portions, and the recessed portions are located between adjacent positive helical segments (10) and negative helical segments (11).

8. The low reflection loss special optical fiber according to claim 1, characterized in that: The reinforcement strips (5) are arranged in plurality, and the plurality of reinforcement strips (5) are evenly distributed along the circumferential direction of the fiber core (1).

9. A low reflection loss special optical fiber as claimed in claim 8, characterized in that: The reinforcement strip (5) is provided with a protrusion (6) extending toward the circumferential side, and the width of the protrusion (6) is smaller than the width of the reinforcement strip (5).

10. A method for preparing a low reflection loss special optical fiber, applicable to a low reflection loss special optical fiber as claimed in any one of claims 1 to 9, characterized in that: The method for preparing the optical fiber comprises the following steps: Preparing an optical fiber body consisting of the fiber core (1), the cladding (2) and the coating layer (3); Winding the heat-conducting wire (9) on the optical fiber body, and leaving a gap between two adjacent turns of the heat-conducting wire (9) to form the heat-conducting space (8); The reinforcing strip (5) is fixedly connected to the heat conducting wire (9).

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