FLEXIBLE FIBER OPTIC TAPE AND OPTICAL CABLE.
Patent Information
- Authority / Receiving Office
- MX · MX
- Patent Type
- Patents
- Current Assignee / Owner
- FIBERHOME TELECOMMUNICATION TECHNOLOGIES CO LTD
- Filing Date
- 2023-06-19
- Publication Date
- 2026-06-12
AI Technical Summary
Conventional flexible fiber optic ribbons suffer from poor flatness and are prone to damage when bent due to the use of resin connections, leading to uneven stress distribution and increased microbending attenuation.
A flexible fiber optic ribbon design featuring a double-sided cladding structure with unclosed buffer cavities between connecting units, allowing air to escape when bent, reducing stress concentration and improving flexibility and flatness.
The design enhances the flexibility and flatness of the fiber optic ribbon, reducing microbending attenuation and improving communication transmission performance while facilitating easy splicing and increasing packaging density.
Smart Images
Figure MX435020B0
Abstract
Description
FLEXIBLE FIBER OPTIC TAPE AND OPTICAL CABLE FIELD OF INVENTION This application relates to the technical field of fiber optic communication, in particular to a flexible fiber optic ribbon and an optical cable. Background of the Invention In recent years, with the rapid advancement of all-optical network construction, traditional underground access network construction has faced new challenges. Based on the need to fully utilize existing underground infrastructure, the demand for ultra-large core and high-density core optical cables is increasing. Finding ways to increase the number of cores in optical cables while maintaining the original outer diameter has become a key area of exploration in the industry. Existing flat optical fiber ribbons have received particular attention due to their high density, high integration, light weight, and ease of multi-fiber splicing, and are widely used in ultra-long core-count optical cables.However, limited by the size of existing flat fiber optic ribbon cables, the size of optical cables with the same number of cores is also relatively large, which has not allowed for a more reasonable and effective use of existing pipes and space. Flexible optical fiber tape is a new type of compact optical fiber tape. Compared to traditional flat optical fiber tape, this new fiber optic cable with flexible optical fiber tape can significantly increase optical fiber density. In the current scenario of maintaining the same outer diameter of the optical cable, the optical cable with flexible optical fiber tape can effectively solve the key problem of expanding the number of optical fiber cores in traditional optical fiber access networks. Flexible optical fiber tape can be wound and arranged flexibly and quickly separated due to the non-continuous, fixed state between each optical fiber, allowing for more optical fiber cores to be accommodated within the same outer diameter of the optical cable. However, many shortcomings still exist in current conventional flexible fiber optic ribbons. For example, when the fiber optic ribbon is bent along its width, the resin used to bond the fibers together is easily damaged, resulting in disadvantages such as poor flatness. Therefore, it is urgent to develop a new structure to meet these technical requirements. SUMMARY OF THE INVENTION The implementation of this application provides a flexible optical fiber tape and optical cable to solve the problem in the related art of the poor flatness of an optical fiber tape caused by the resin used to connect the optical fibers to form the optical fiber tape, which is prone to damage when the optical fiber tape is bent in the width direction. In a first aspect, a flexible optical fiber ribbon is provided, comprising a plurality of core ribbon groups, wherein the core ribbon groups are configured in parallel, and each core ribbon group comprises three optical fiber units; the three optical fiber units of each core ribbon group are configured in parallel, each of the optical fiber units located on two sides comprises one optical fiber, and the optical fiber unit located in the middle comprises at least one optical fiber, which is configured to be parallel and connected; two adjacent core ribbon groups and two adjacent optical fiber units in each core ribbon group are connected respectively by means of a plurality of first connecting parts, which are arranged at intervals in one direction along the length of the optical fibers;and taking as a reference plane a plane passing through the axes of two adjacent optical fibers, each of the first connecting parts comprises two connecting units located respectively above and below the reference plane: and a damping cavity is formed between two adjacent optical fibers and between the two connecting units above and below the reference plane. In some embodiments, some ends of the two connecting units of the first connecting part are connected together to form a closed end of the damping cavity, and the other ends of the two connecting units of the first connecting part are separated from each other to form an open end of the damping cavity; or the intermediate parts of the two connecting units of the first connecting part are connected together to form a closed end of the damping cavity, and the ends of the two connecting units of the first connecting part located on the same side of the closed end are separated from each other to form an open end of the damping cavity. In some embodiments, in the first connection part between each two groups of adjacent core tapes, or in the first connection part between each two adjacent optical fiber units in the core tape group, a distance L1 between two adjacent first connection parts is greater than a length L2 of the first connection part in the direction of the optical fiber length. In some embodiments, a distance L1 between each two adjacent first connection parts and a length L2 of the first connection part in the direction of the optical fiber length satisfy L1 :L2 > 2:1. In some embodiments, along the width direction of the flexible optical fiber ribbon, each pair of adjacent first connection parts are spaced in the direction of the optical fiber length. In some embodiments, along the width direction of the flexible optical fiber ribbon, a distance L3 between each pair of adjacent first connection parts in the direction of the optical fiber length is greater than or equal to 0. In some embodiments, when the optical fiber unit located in the middle comprises a plurality of optical fibers, the optical fibers are arranged in parallel, and every two adjacent optical fibers are connected by means of a second connecting part, and along the direction of the length of the optical fiber, the second connecting part extends from one end of the optical fiber to the other end. In some implementations, the first connecting part is made of photocurable resin. In some embodiments, a linear expansion coefficient of the light-cured resin at normal temperature is less than 8*10-4 / °C, and an elongation at break is greater than 60%. Secondly, an optical cable is provided comprising: an outer sheath: and a plurality of flexible optical fiber ribbons as described in any of the above, wherein the outer sheath receives the flexible optical fiber ribbons. The beneficial effects of the technical solution provided in this application are as follows: The implementation of this application provides a flexible optical fiber ribbon and an optical cable, which are connected by means of the first connecting part, and. at the same time, the first connecting part comprises two connecting units, so that the coating points on the optical fiber are in a double-sided coating state, so that the optical fiber ribbon can be wound freely in both directions of the upper and lower surfaces, which effectively solves the uneven distribution of surface coating tension in the joint area of the two optical fibers caused by single-sided resin coating, and can reduce the risk of potential stress concentration of the optical fiber ribbon, reduce micro-bending attenuation and improve communication transmission performance. Due to the double-sided coating structure, the tensile force of the connecting units in both directions of the upper and lower surfaces of the flexible optical fiber tape is constant, which can ensure that the flatness of the cross-section of the optical fiber tape after unfolding is good and convenient for subsequent batch fusion splicing. Due to the double-sided coating structure, it can also ensure that after the connecting unit on one side breaks under tension, the optical fiber ribbon can still remain in a connected state and is not easily dispersed, thus facilitating the recovery of a straight state for batch termination. Through the damping cavity, the flexibility and damping performance of the first connection part can be improved, thus preventing the first connection part from being unintentionally damaged and preventing the optical fiber tape from having poor flatness due to damage to the first connection part. The present application adopts an open damping cavity, so that the damping cavity communicates with the outside atmosphere, and when the optical fiber ribbon is bent along the width direction, the air in the damping cavity is expelled, ensuring the flexibility and damping of the first connection part, preventing the first connection part from being damaged and making the optical fiber ribbon have better flatness after recovery. Furthermore, the volume of the first connection part is compressed, which is beneficial for increasing the packing density of the optical fiber; in addition, the buffer cavity is deformed during the compression process, which can effectively absorb radial pressure, thus reducing the risk of potential stress concentration of the optical fiber ribbon such as microbending attenuation, and improving communication transmission performance. BRIEF DESCRIPTION OF THE DRAWINGS To better illustrate the technical solution in the embodiments of the present application, the necessary drawings in the description of the embodiments will be briefly presented below, and it is evident that the drawings in the following description are part of the embodiments of the present application; for those skilled in the art, other drawings based on these drawings can also be obtained without any inventive effort. FIG. 1 is a structural diagram of a flexible optical fiber ribbon as specified in this application: FIG. 2 is a view in direction AA of FIG. 1; FIG. 3 is a schematic diagram of a buffer cavity formed by an optical fiber and a first connecting part in the implementation of the present application (single open end); FIG. 4 is a schematic diagram of a buffer cavity formed by an optical fiber and a first connecting part in the implementation of the present application (double open end): FIG. 5 is a schematic diagram of a force transmission direction of an optical fiber ribbon when bent in the performance of the present application. In the Figs.: reference plane A; 1-core tape group; 2-optical fiber unit; 3-optical fiber; 4-first connection part; 40-connection unit; 5-buffering cavity; 50-closed end; 51-open end; 6-second connection part. DETAILED DESCRIPTION OF THE ACHIEVEMENTS In order to clarify the purpose, technical solutions, and advantages of the embodiments covered by this application, the technical solutions in said embodiments shall be clearly and completely described in conjunction with the drawings in said embodiments. Obviously, the described embodiments are only a portion of the embodiments covered by this application, not all of them. Based on the embodiments covered by this application, all other embodiments obtained by a person skilled in the art without inventive effort shall fall within the scope of protection of this application. The implementation of this application provides a flexible optical fiber tape and optical cable, which can solve the problem in the related art of the poor flatness of an optical fiber tape caused by the resin used to connect the optical fibers to form the optical fiber tape, which is prone to damage when the optical fiber tape is bent in the width direction. As shown in FIG. 1 and FIG. 2, the implementation of the present application provides a flexible optical fiber tape, the flexible optical fiber tape comprising a plurality of core tape groups 1, the core tape groups 1 are configured in parallel, and each core tape group 1 comprises three optical fiber units 2. The three optical fiber units 2 of each core tape group 1 are configured in parallel, each of the optical fiber units 2 located on two sides comprises one optical fiber 3, and the optical fiber unit 2 located in the middle comprises at least one optical fiber 3, which is configured to be in parallel and connected. Two adjacent core ribbon groups 1 are connected by a plurality of first connecting parts 4, which are arranged at intervals in a direction along the length of the optical fibers 3, and two adjacent optical fiber units 2 in each core ribbon group 1 are also connected by means of a plurality of first connecting parts 4, which are arranged at intervals along the length of the optical fibers 3. Taking a plane passing through the axes of two adjacent optical fibers 3 as reference plane A, each of the first connecting parts 4 comprises two connecting units 40 located respectively above and below reference plane A and are connected by means of the first connecting part 4. At the same time, the first connecting part 4 comprises two connecting units 40, so that the coating points of the optical fiber 3 are in a double-sided coating state, so that the optical fiber ribbon can be wound freely in both directions of the upper and lower surfaces, effectively solving the uneven distribution of surface coating stress in the joint area of the two optical fibers 3 caused by single-sided resin coating, and can reduce the risk of potential stress concentration of the optical fiber ribbon.It reduces microbending attenuation and improves communication transmission performance. Due to the double-sided coating structure, the tensile force of the 40 connecting units in both directions of the upper and lower surfaces of the flexible optical fiber tape is constant, which can ensure that the flatness of the cross-section of the optical fiber tape after unfolding is good and convenient for subsequent batch fusion splicing. Due to the double-sided coating structure, after the 40-connecting unit on one side breaks under tension, it can be ensured that the optical fiber tape can still remain in a connected state and is not easily dispersed, thus facilitating the recovery of a straight state for batch termination. As shown in FIG. 2, a damping cavity 5 is formed between two adjacent optical fibers 3 and between the two connecting units 40 above and below the reference plane A, and through the damping cavity 5, the flexibility (foldability) and damping (relaxation) of the first connecting part 4 can be improved, thus preventing the first connecting part 4 from being unintentionally damaged and avoiding poor flatness of the optical fiber ribbon due to damage to the first connecting part. After extensive and long-term research, the applicant found that when manufacturing the first connection part 4, if some closed air bubbles are generated in the first connection part 4 to form the damping cavity 5, the flexibility and damping of the first connection part 4 can be improved to some extent, but new problems will arise: on the one hand, there is still gas in the air bubbles, and when the optical fiber ribbon is bent along the width direction, the air bubbles will be compressed, and the greater the degree of bending, the greater the gas pressure in the air bubbles, and the greater the force required, which does not lead to the bending operation: and, on the other hand, this pressure resists bending in the radial direction, creating a risk of potential stress concentration for the optical fiber ribbon. Therefore, in order to resolve the aforementioned defects, the present application adopts an open damping cavity, so that the damping cavity communicates with the outside atmosphere, and when the optical fiber ribbon is bent along the width direction, the air in the damping cavity is expelled, ensuring the flexibility and damping of the first connection part, preventing damage to the first connection part 4 and making the optical fiber ribbon have better flatness after recovery.Furthermore, the volume of the first part of connection 4 is compressed, which is beneficial for increasing the packing density of the optical fiber: in addition, the buffer cavity 5 is deformed during the compression process, which can effectively absorb radial pressure, thus reducing both the risk of potential stress concentration of the optical fiber ribbon and micro-bending attenuation, and improving communication transmission performance. When the optical fiber ribbon returns to its straight state, the buffer cavity 5 fills with air. The buffer cavity 5 then recovers to form an effective support, further ensuring the flatness of the optical fiber after the flexible optical fiber ribbon returns to its straight state, to facilitate batch fusion splicing. The unclosed damping cavity has several forms, such as a single open-ended form and a double open-ended form. As shown in FIG. 3, in a preferred embodiment, the shape of the single open end is adopted, specifically, some ends of the two connecting units 40 of the first connecting part 4 are connected together to form a closed end 50 of the damping cavity 5, and the other ends of the two connecting units 40 of the first connecting part 4 are separated from each other to form an open end 51 of the damping cavity 5. As shown in FIG. 3, in a preferred embodiment, the double open-end form is adopted, specifically, the intermediate parts of the two connecting units 40 of the first connecting part 4 are connected together to form a closed end 50 of the damping cavity 5, and the ends of the two connecting units 40 of the first connecting part 4 located on the same side of the closed end 50 are separated from each other to form an open end 51 of the damping cavity 5. In some preferred embodiments, as shown in FIG. 1, in the first connection part 4 between each two groups of adjacent core ribbons 1, or in the first connection part 4 between each two adjacent optical fiber units 2 in the core ribbon group 1, a distance L1 between two adjacent first connection parts 4 is greater than a length L2 of the first connection part 4 in the direction of the optical fiber length 3. The purpose of making the distance L1 of the first connection part 4 greater than the length L2 of the first connection part 4 is twofold: 1) Under the premise of using high-modulus curable resin to ensure connection strength, increasing the overall proportion of the unconnected portion leads to high flexibility of the optical fiber tape and facilitates winding. Generally, to ensure strength, the lower the L2 value, the better, and L2 should be as close to 0 as possible. 2) The amount of resin used can also be reduced to decrease costs. In some preferred embodiments, the distance L1 between each two adjacent first connection parts 4 and the length L2 of the first connection part 4 in the direction of the optical fiber length 3 satisfy L1 :L2>2:1. In some preferred embodiments, as shown in FIG. 1, along the width direction of the flexible optical fiber tape, each pair of adjacent first connecting parts 4 are spaced apart along the length direction of the optical fiber 3, primarily to increase the overall proportion of unconnected parts in the same section of the optical fiber tape, thereby improving the overall winding capability of the optical fiber tape. In some preferred embodiments, as shown in FIG. 1, along the width direction of the flexible optical fiber tape, a distance L3 between each pair of adjacent first connecting parts 4 along the length direction of the optical fiber 3 is greater than or equal to 0, preferably L3 = (L1 - L2) / 2. In some preferred embodiments, as shown in FIG. 1 and FIG. 2, when the optical fiber unit 2 located in the middle comprises a plurality of optical fibers 3, the optical fibers 3 are arranged in parallel, and every two adjacent optical fibers 3 are connected by means of a second connecting part 6, and along the direction of the length of the optical fiber 3, the second connecting part 6 extends from one end of the optical fiber 3 to the other end. The plurality of optical fibers 3 comprised in the optical fiber unit 2 in the middle are in a fully connected structure, and combined with the interval connection of the first connecting part 4, the optical fiber ribbon is in a partially connected + fully connected structure, which can better ensure the flatness of the optical fiber after the flexible optical fiber ribbon returns to its straight state. When the flexible optical fiber ribbon is bent, compared to the fully connected structure, the partially connected part (i.e., the first connecting part 4) can use the damping cavity 5 and the closed end 50 to migrate the radial pressure generated by the bending of the beam towards the axial direction to play the role of a force component, effectively reducing the risk of stress concentration that can be caused by winding and reducing micro-bending attenuation, as shown in FIG. 5. In FIG., the direction of the arrow is the direction of force transmission. In some preferred embodiments, the first part of connection 4 is made of photocurable resin. In some preferred embodiments, a linear expansion coefficient of the light-cured resin at normal temperature is less than 8><10-4 / °C, and an elongation at break is greater than 60%. The implementation of this application further provides an optical cable, the optical cable comprising an outer sheath; and a plurality of flexible optical fiber ribbons provided in the embodiments mentioned above, the outer sheath receiving the flexible optical fiber ribbons. In the description of this application, it should be noted that the orientation or positional relationship indicated by the terms "upper," "lower," etc., is based on the orientation or positional relationship shown in the drawings. This is solely for the convenience of describing this application and to simplify the description, rather than to indicate or imply that the device or element referred to must have a specific orientation, be configured, and be operated in a specific orientation. Therefore, it cannot be construed as a limitation of this application. Unless clearly specified and limited otherwise, the terms "installation," "connected," and "connection" should be understood in a broad sense.For example, it may be a fixed connection, a removable connection, or an integral connection; it may also be a mechanical or electrical connection; it may be connected directly, or indirectly through an intermediate medium, or it may be internal communication between two components. For those skilled in the art, the specific meanings of the terms mentioned above in this application may be understood according to specific circumstances. It should be noted that the relational terms such as "first" and "second" are used only to distinguish one entity or transaction from another in this application and do not necessarily require or imply any actual relationship or order between these entities or transactions. Furthermore, the terms "include," "comprise," or any other variant thereof, are intended to cover non-exclusive inclusion, such that a process, method, article, or device comprising a set of elements not only comprises those elements but also includes those not explicitly listed or further comprises elements inherent to the process, method, article, or device. Without further restrictions, the elements defined by the phrase "comprising a..." do not preclude the existence of other such elements of the process, method, article, or device comprising those elements. The foregoing are merely embodiments of this application, intended to enable those skilled in the art to understand or implement it. For those skilled in the art, various modifications to these embodiments will be obvious, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not limited to the embodiments shown herein, but is subject to the broader scope consistent with the novel principles and features applied herein.
Claims
1. A flexible optical fiber ribbon, wherein the flexible optical fiber ribbon comprises a plurality of core ribbon groups (1), wherein the core ribbon groups (1) are configured in parallel, and each core ribbon group (1) comprises three optical fiber units (2); the three optical fiber units (2) of each core ribbon group (1) are configured in parallel, each of the optical fiber units (2) located on two sides comprises an optical fiber (3), and the optical fiber unit (2) located in the middle comprises at least one optical fiber (3), which is configured to be in parallel and connected;Two groups of adjacent core ribbons (1) and two adjacent optical fiber units (2) in each group of core ribbons (1) are connected respectively by means of a plurality of first connecting parts (4), which are arranged at intervals in a direction along the length of the optical fibers (3): taking as a reference plane (A) a plane passing through the axes of two adjacent optical fibers (3), each of the first connecting parts (4) comprises two connecting units (40) situated respectively above and below the reference plane (A); and a buffer cavity (5) is formed between two adjacent optical fibers (3) and between the two connecting units (40) above and below the reference plane (A).
2. The flexible optical fiber ribbon according to claim 1, wherein one end of the two connecting units (40) of the first connecting part (4) is connected together to form a closed end (50) of the buffer cavity (5), and the other ends of the two connecting units (40) of the first connecting part (4) are separated from each other to form an open end (51) of the buffer cavity (5); or the intermediate parts of the two connecting units (40) of the first connecting part (4) are connected together to form a closed end (50) of the buffer cavity (5), and the ends of the two connecting units (40) of the first connecting part (4) located on the same side of the closed end (50) are separated from each other to form an open end (51) of the buffer cavity (5).
3. The flexible optical fiber tape according to claim 1, wherein in the first connecting part (4) between each two groups of adjacent core tapes (1), or in the first connecting part (4) between each two adjacent optical fiber units (2) in the group of core tapes (1), a distance L1 between two adjacent first connecting parts (4) is greater than a length L2 of the first connecting part (4) in the direction of the optical fiber length (3).
4. The flexible optical fiber tape according to claim 1, wherein a distance L1 between each two adjacent first connecting parts (4) and a length L2 of the first connecting part (4) in the direction of the optical fiber length (3) satisfy L1 :L2 > 2:
1.
5. The flexible optical fiber tape according to claim 1, wherein along the width direction of the flexible optical fiber tape, each pair of adjacent first connecting parts (4) are spaced in the length direction of the optical fiber.
6. The flexible optical fiber tape according to claim 5, wherein along the width direction of the flexible optical fiber tape, a distance L3 between each two adjacent first connecting parts (4) in the length direction of the optical fiber (3) is greater than or equal to 0.
7. The flexible optical fiber ribbon according to claim 1, wherein the optical fiber unit (2) located in the middle comprises a plurality of optical fibers (3), the optical fibers (3) are arranged in parallel, and each pair of adjacent optical fibers (3) are connected by means of a second connecting part (6), and along the length direction of the optical fiber (3), the second connecting part (6) extends from one end of the optical fiber (3) to the other end.
8. The flexible optical fiber tape according to claim 1, wherein the first connecting part (4) is made of photocurable resin.
9. The flexible optical fiber tape according to claim 8, wherein the linear expansion coefficient of the photocurable resin at normal temperature is less than 8x10-4 / °C, and the elongation at break is greater than 60%.
10. An optical cable, wherein the optical cable comprises: an outer sheath; and a plurality of flexible optical fiber ribbons according to any of claims 1 to 9, wherein the outer sheath receives the flexible optical fiber ribbons.