JP2011002508A - Optical jumper unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical jumper unit having a jumper optical fiber cord which is excellent in bending loss characteristics, and for avoiding communication shutoff due to catch or the like.SOLUTION: The optical jumper unit includes: a first connector 23 disposed in a case 21 so that optical connection from outside the case 21 is performed; an optical splitter 24 to multiplex/demultiplex signals, disposed in the case 21, whose multiplexing side is connected to the first connector 23 through an optical fiber 34; and single mode optical fiber cords 31, one end of each of which is connected to the demultiplexing side of the optical splitter 24, and the other end of each of which is connected to the second connector 32; wherein an optical fiber cord composed of a hole-assisted fiber is used as the optical fiber cord 31.

Description

  The present invention relates to a high-density / high-reliability optical jumper unit provided in, for example, an in-house optical wiring facility (in-house wiring rack) of a communication company.

  With the rapid spread of optical access services against the backdrop of the realization of 20 million optical accesses in 2010, the era of mass service of optical services has been entered, and accordingly, in-house optical facilities have increased rapidly (for example, Non-Patent Document 1, 2). In the next-generation in-house optical equipment, it is expected that the increasing optical equipment will be accommodated in a limited space. Therefore, there is a possibility that space saving by higher density than before is required. However, as the density increases, there is a concern that optical cords, optical cables, etc. will become congested, making maintenance and management difficult. Therefore, in the next-generation in-house optical equipment, there is a demand for in-house optical wiring and management technology having both safety and certainty corresponding to higher density (for example, see Non-Patent Documents 1 to 7).

  FIG. 2 is an explanatory diagram illustrating a conventional in-house optical wiring facility. In FIG. 2, 11 is a communication company building, 12 is an in-house optical cable, 13 is an identification tag, 14 is an outside optical cable, OLT (Optical Line Terminal) is a transmission device, IDM-A, IDM-B (IDM: Integrated Distribution Module). Is a dedicated wiring rack.

  That is, the in-house optical wiring facility of the telecommunications company building 11 is connected to the transmission device OLT that provides the IP service or the like through the in-house optical cable 12 and the identification tag 13, and the dedicated wiring rack IDM-B It is connected to the dedicated wiring rack IDM-A via the in-house optical cable 12 and the identification tag 13. A customer home 15 is connected to the dedicated wiring rack IDM-A. In this case, efficient optical wiring accommodation is realized by installing dedicated racks IDM-A and IDM-B on the customer's home 15 side and the transmission device OLT side, respectively, and dividing the function (for example, non-patent References 3-6.)

  As described above, the current in-house optical wiring has a configuration that is considered for the purpose of high efficiency operation and easy workability. However, it is expected that higher density will be required for next-generation in-house optical wiring equipment. Therefore, as an issue that may occur during optical wiring, optical cords and optical cables may be accidentally hooked during work such as new installation or abolition. As a result, bending loss may increase and communication may be interrupted. In particular, the jumper work is very frequent, so the above-mentioned problems are likely to occur, and high reliability is expected for the jumper optical fiber cord that is a part of the optical jumper unit.

H. Shinohara, “Overview of Japan FTTH market and NTT's strategies for the full full scale FTTHera,” presented at the 32nd Europe. O. Yamauchi, “Trends in optical access network technologies tower '30 million optical subscribers by 2010 ',” NTT Technical Review 4, 21. M Tachikura, K Mine, H Izumita, S Uruno, M .; Nkamura, “Newly developed optical fiber distribution system and cable management in central office,” Proc. 50th IWCS, pp. 98-105. Shigenori Uruno, Fumi Izumida, Satoshi Nakamura, “Economic MU Connector Technology in In-House Optical Wiring Management System,” NTT Technical Journal, vol. 15, no. 10, pp. 12-15, 2003 Shigenori Uruno, Masao Tatekura, Fumi Izumida, Tsuneji Mine, Nobuo Tomita “Integrated Wiring Module in In-House Optical Wiring Management System (Design of IDM”, Shingaku Sodai, B-10-25, 2000 Koji Mine, Yoshitaka Enomoto, Hisashi Izumita, M .; Tachikura, N .; Tomita, J.M. Yamaguchi, K .; Sasakura and K.K. Kaneko, “Automatic Cross-connecting Fiber Termination Module,” APCC / OECC'99, vol. 1, pp. 267-269, 1999 Masato Mizukami, Mitsuhiro Makihara, Shuichiro Inagaki, Kunihito Sasakura “Development of Automatic Optical Wiring Switching Device”, NTT Technical Journal, vol. 16, no. 9, pp. 43-46, 2004.

  The present invention has been made in view of the above circumstances, and in addition to being excellent in bending loss characteristics to the jumper optical fiber cord and capable of avoiding communication interruption due to hooking, etc., has compatibility with existing equipment, equivalent to existing equipment The objective is to provide an optical jumper unit that achieves the basic characteristics, economy, and storage of the projector.

  In order to achieve the above object, the optical jumper unit of the present invention is provided in a case, and is connected to a first connector provided to be optically connectable from the outside of the case, and one end of each of the first connector, In an optical jumper unit comprising a single-core optical fiber cord having a second connector connected to the other end, an optical fiber cord comprising a hole assist fiber (HAF) is used as the optical fiber cord. It is.

  An optical jumper unit according to the present invention is provided in a case and provided with a first connector provided so as to be optically connectable from the outside of the case, and provided in the case, and an optical fiber is connected to the first connector. An optical splitter that multiplexes and demultiplexes the signal to which the multiplexing side is connected, and a single-core optical fiber cord in which one end is connected to the demultiplexing side of the optical splitter and the second connector is connected to the other end. In the optical jumper unit, an optical fiber cord made of a hole assist fiber is used as the optical fiber cord.

  According to the present invention, in the optical jumper unit, the optical fiber and the first connector have a single mode propagation characteristic.

  In the optical jumper unit, the connecting portion on one end side of the optical fiber cord and the single-mode fiber (SMF) connecting portion on the demultiplexing side of the optical splitter are revolved so as to be fused in a multi-core manner. It is characterized by being connected.

  According to the present invention, in the optical jumper unit, an optical fiber cord having a diameter of 1.1 mm or less and having a MU connector connected to the other end is used as the optical fiber cord.

  In the optical jumper unit, a single mode fiber is connected to a hole assist fiber inside a ferrule of a second connector connected to the other end of the optical fiber cord. is there.

  According to the present invention, in the optical jumper unit, as the optical fiber cord, an optical fiber cord having a colored layer that facilitates coating removal between a coating layer of the optical fiber and an overcoat layer of the optical fiber core It is characterized by using.

  Further, the present invention uses an optical fiber cord in which the outer coating of the optical fiber cord is provided with a stripe pattern decoration so as to enable discrimination of the optical fiber cord as the optical fiber cord in the optical jumper unit. It is characterized by.

  In the optical jumper unit, the optical jumper unit may use an optical fiber cord provided with a tag that can be identified by an optical fiber cord or a connector so that the optical fiber cord can be identified. It is characterized by.

  The optical jumper unit of the present invention can greatly improve the bending loss characteristics and greatly improve the reliability during wiring work by adopting the hole assist fiber as the strand of the jumper optical fiber cord. is there. In addition, since the cord diameter is reduced, high-density optical wiring can be accommodated, and since the MU connector is used, the compatibility with existing equipment is very high. Further, it can be rebonized and can be fused together with a single-mode fiber that is optically wired in an optical jumper unit, which greatly contributes to accommodation and economy. In addition, the optical fiber cord connector can be made easy and economical by using a method of fusion bonding with a single mode fiber and sealing with holes.

FIG. 3 is an explanatory diagram illustrating a configuration of an optical jumper unit according to an embodiment of the present invention. It is composition explanatory drawing which shows the conventional local optical wiring form. It is a characteristic view which shows the bending radius dependence of the bending loss which concerns on embodiment of this invention. (A) is a characteristic view showing the cord outer diameter dependence of the number of cores that can be accommodated per rack according to the embodiment of the present invention, and (b) is a jumper cord per time according to the embodiment of the present invention. It is a characteristic view which shows the code outer diameter dependence of work time. It is composition explanatory drawing which shows the sealing process of the hole of the optical fiber cord using HAF which concerns on embodiment of this invention, and a connectorization process. It is a characteristic view which shows the hole sealing distance dependence of the connection loss and the mechanical enemy strength of a hole sealing part which concern on embodiment of this invention. (A) is a characteristic view showing a histogram of connection loss according to the embodiment of the present invention, (b) is a characteristic diagram showing a histogram of reflection loss according to the embodiment of the present invention. It is sectional drawing which shows the optical fiber cord which has the colored layer which concerns on embodiment of this invention. It is a characteristic view which shows the thickness dependence of the coloring layer of the yield of the coating removal which concerns on embodiment of this invention. It is a characteristic view which shows the fiber length dependence of the ratio of the higher mode which concerns on embodiment of this invention of SMF. It is composition explanatory drawing which shows the case where a striped pattern is given to the outer coating of the optical fiber cord which concerns on embodiment of this invention, or a tag is installed.

Hereinafter, embodiments of the present invention will be described in detail.
FIG. 1 is a configuration explanatory view showing an optical jumper unit according to an embodiment of the present invention. In FIG. 1, 21 is a case of an optical jumper unit, 22 is a transmission device (OLT) that provides an IP service, 23 is a first connector, 24 is a four-branch optical splitter (× 2) that multiplexes and demultiplexes signals, 25 is a 0.25 mm fiber, 26 is a rebonized part, 27 is an 8-core batch fused part, 281 is a 0.125 mm fiber (usually SMF), 282 is a 0.125 mm fiber (HAF), and 29 is a 0.25 mm fiber. 30 is a 0.5 mm fiber core, 31 is a single 1.1 mm optical fiber cord, 32 is a MU connector, 33 is an optical network unit (ONU), and 34 is an optical fiber. is there.

  In FIG. 1, a transmission device (OLT) 22 outside the case 21 is optically connected to a first connector 23 provided in the case 21 of the optical jumper unit. In the case 21, the multiplexing side of the optical splitter 24 is connected to the first connector 23 via an optical fiber 34. In the eight-core batch fusion portion 27 of the rebonize unit 26, one end of the fiber 282 of the fiber strand 29 is fused and connected to the fiber 281 of the demultiplexing side fiber strand 25 of the optical splitter 24.

  The outer coating and Kevlar of the optical fiber cord 31 are removed to form the fiber core wire 30, the overcoat layer of the fiber core wire 30 is removed to form the fiber strand 29, and the coating layer of the fiber strand 29 is removed Thus, a fiber (HAF) 282 is formed. An MU connector 32 is connected to the other end of the optical fiber cord 31, and an ONU 33 is connected to the MU connector 32 via an optical subscriber line network.

  The first connector 23 and the optical fiber 34 can be configured to have single mode propagation characteristics.

  In other words, the optical jumper unit is composed of an optical fiber cord using a hole assist fiber (HAF), a revolving part, a multi-core batch fusion part, a four-branch splitter, and a MU connector.

  In more detail, the process of rebonizing and multi-core batch fusion will be described in detail. First, a predetermined amount of the outer coating of the optical fiber cord and the Kevlar are peeled off, and then the coating of the overcoat layer of the 0.5 mmφ core wire is removed. To make a 0.25 mmφ strand. A plurality of optical fiber cords that have undergone such processing are prepared, and the strand portions are arranged in parallel to perform rebonation. Next, the same number of single-mode fibers as the optical fiber cords are prepared and re-ribonized. Further, after removing a part of the reboned strands of the optical fiber cord and the single mode fiber to 0.125 mmφ, multi-core (for example, 8 cores) are fused together.

  FIG. 3 shows the bending radius dependence of bending loss (1.55 μm, 10 turns) in an optical fiber cord using HAF. As can be seen from FIG. 3, in the single mode fiber (SMF), when the bending radius becomes 10 mm or less, the bending loss increases rapidly, but in HAF, even if the bending radius is 3 mm, almost no bending loss occurs.

  FIG. 4A shows the dependence of the number of cores that can be accommodated on one rack on the optical fiber cord diameter. As can be seen from FIG. 4 (a), 4000 cores can be accommodated by setting the cord diameter to 1.1 mm. FIG. 4B shows the code diameter dependence of the work time per jumper work (total time for new installation and abolition). The number of accommodated cores conforms to FIG. As can be seen from FIG. 4 (b), there is almost no change in the working time until the cord diameter reaches 1.0 mmφ, but when the cord diameter becomes smaller than that, the working time increases rapidly. Therefore, in order to achieve both high-density wiring and working time, it is desirable to use a cord near 1.0 mmφ. In this embodiment, the 1.1 mmφ cord used in the current system is adopted.

  FIG. 5 shows the hole sealing process and connectorization process of HAF. First, a single mode fiber (SMF) is fusion spliced to seal the air holes of the HAF optical fiber cord 31 ([1]). Thereafter, the excess single mode fiber (SMF) is cut ([2]). Next, it is mounted on the ferrule 41 ([3]) and the ferrule end face is polished ([4]). Further, the connector housing 42 is completely attached ([5]). That is, the optical fiber cord of the optical jumper unit is connected to a minute single mode fiber so that the hole assist fiber is sealed in the hole inside the ferrule 41 of the second connector, and is made into a connector.

  FIG. 6 shows the hole sealing distance dependence of the connection loss and the mechanical strength of the hole sealing portion. The connection loss tends to increase monotonously until the sealing distance (distance from the connector end face of the portion where the hole is sealed) is about 10 mm. On the other hand, the mechanical strength increases rapidly with respect to the sealing distance, starts to saturate near 0.1 mm, and completely saturates at 3 mm. Therefore, in order to achieve both the connection loss and the mechanical strength, it is desirable to set the sealing distance to about 0.1 to 3 mm.

  7A and 7B show histograms of connection loss and reflection loss of the MU connector when the sealing distance is 1 mm. The measurement wavelength was 1.55 μm. Each connector achieves a connection loss of 0.5 dB or less and a reflection loss of 50 dB or more, and sufficiently satisfies the system requirements (connection loss: 0.5 dB or less, reflection loss: 35 dB or more). In addition, since the time and cost required for the polishing work occupy most of this process, the work time and work cost for hole sealing are almost none. Therefore, if the manufacturing cost of the optical fiber cord of this embodiment is the same as that of the conventional optical fiber cord, the optical fiber cord with a connector can be realized at substantially the same cost.

  FIG. 8 is a cross-sectional view showing an optical fiber cord having a colored layer according to an embodiment of the present invention. In FIG. 8, 51 is a core, 52 is a hole assist fiber (φ125 mm), 53 is a hole, 54 is a coating layer (φ250 mm) of an optical fiber, 55 is a colored layer (thickness 7 μm), and 56 is an overcoat layer (Φ500 mm). That is, as shown in FIG. 1, in the rebonization, the 0.5 mmφ core wire overcoat layer is removed to form a 0.25 mmφ optical fiber. However, since the overcoat layer and the coating layer of the optical fiber are in close contact, it is difficult to remove the coating. Therefore, in this embodiment, the colored layer 55 is provided between the two coating layers in order to facilitate the removal of the coating. In FIG. 8, kevlar and outer coating provided on the outer periphery of the overcoat layer are omitted.

  FIG. 9 shows the dependency of the removal rate of coating removal on the thickness of the colored layer when a colored layer is provided and 100 mm of coating removal is performed once. As can be seen from FIG. 9, a high yield of coating removal can be obtained when the thickness of the colored layer is 3 to 20 μm. Therefore, it is desirable that the thickness of the colored layer be 3 to 20 μm. Examples of the colorant material include a photopolymerization initiator, a monomer, an oligomer, and a pigment.

  The re-fiberized optical fiber cord extends from an optical splitter mounted in the optical jumper unit, and is multi-core collectively fused with a single-mode fiber that is also re-organized with multi-core. However, since the excitation conditions of various propagation modes differ between HAF and single mode fiber, there is a possibility that mode conversion occurs near the connection part of the two fibers and the higher order mode is excited. Deterioration factor). However, the excited higher order modes may be emitted outside during propagation through the single mode fiber.

  FIG. 10 shows the SMF fiber length dependence of the ratio of higher-order modes excited during propagation from the HAF side to the single mode fiber. As can be seen from FIG. 10, the ratio of higher-order modes is significantly reduced at 3 cm or more. Since the fiber length that can be mounted on the optical jumper unit is 80 cm, the length of the single mode fiber is preferably between 3 and 80 cm. With the above-described configuration, high storage capacity and economy can be achieved by saving space and shortening the working time by multi-core batch fusion.

  FIG. 11 shows an example of the decoration of the outer coating of the optical fiber cord. When a new optical fiber cord using HAF is added, it is necessary to instantly discriminate from a conventional optical fiber cord. Therefore, a decoration that facilitates discrimination is desirable. Since the current equipment is often colored with one color other than black, in this embodiment, the outer coating of the optical fiber cord is decorated with a black stripe pattern (3 cm) 61 as shown in FIG. Make discrimination easier. In consideration of the fact that black has the problem that leaked light at the time of contrasting the cores is easily absorbed and that the outer coating of the optical fiber cord may be printed with black or the like, the interval between the stripe patterns should be 3 cm or more. Is appropriate. Since the width of the reading part of a general core wire contrast device currently on the market is about 3 cm, the interval of the stripe pattern is set to 3 cm or more as a suitable example in this embodiment. However, since it is conceivable that the width of the reading section of the cord contrast device and the code length necessary for reading will be changed in the future, it goes without saying that the appropriate striped pattern interval is also changed accordingly.

  As shown in FIG. 11, the optical fiber cord 31 can be easily identified by mounting the tag 62 with identification information attached to the MU connector 32 or the optical fiber cord 31.

  Although the optical jumper unit of the four-branch optical splitter is shown in the present embodiment, it is needless to say that the present invention can be applied to an optical jumper unit using an optical splitter having other branching ratio. In addition, the same effect can be obtained even when the optical splitter is not mounted. The characteristics shown in FIGS. 3 to 7, 9, and 10 are examples, and the application range of the present invention is not limited to this range.

  Further, the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

  DESCRIPTION OF SYMBOLS 21 ... Case of optical jumper unit, 22 ... Transmission apparatus (OLT) providing IP service, 23 ... First connector, 24 ... Four-branch optical splitter (x2) for multiplexing / demultiplexing signals, 25 ... 0. 25 mm fiber strand, 26 ... revolved portion, 27 ... 8-core batch fused portion, 281 ... 0.125mm fiber (usually SMF), 282 ... 0.125mm fiber (HAF), 29 ... 0.25mm fiber strand, 30 ... 0.5 mm fiber core, 31... 1.1 mm optical fiber cord, 32 .MU connector, 33. Optical subscriber line network unit (ONU), 34.

Claims (9)

A first connector provided in the case and provided so as to be optically connectable from the outside of the case;
In an optical jumper unit comprising a single-core optical fiber cord having one end connected to the first connector and the other end connected to the second connector,
An optical jumper unit using an optical fiber cord made of a hole assist fiber as the optical fiber cord. A first connector provided in the case and provided so as to be optically connectable from the outside of the case;
An optical splitter that is provided in the case and multiplexes and demultiplexes a signal having a multiplexing side connected to the first connector via an optical fiber;
In an optical jumper unit comprising a single-core optical fiber cord having one end connected to the demultiplexing side of the optical splitter and the second connector connected to the other end,
An optical jumper unit using an optical fiber cord made of a hole assist fiber as the optical fiber cord.   3. The optical jumper unit according to claim 2, wherein the optical fiber and the first connector have single mode propagation characteristics.   4. The optical jumper unit according to claim 3, wherein the connection portion on one end side of the optical fiber cord and the single mode fiber connection portion on the demultiplexing side of the optical splitter are rebonized and collectively fused and connected with multiple cores. Optical jumper unit characterized by that.   5. The optical jumper unit according to claim 1, wherein an optical fiber cord having a diameter of 1.1 mm or less and having a MU connector connected to the other end is used as the optical fiber cord. Optical jumper unit.   6. The optical jumper unit according to claim 1, wherein a single mode fiber is connected to the hole assist fiber inside the ferrule of the second connector connected to the other end of the optical fiber cord. Characteristic optical jumper unit.   The optical jumper unit according to any one of claims 1 to 6, wherein the optical fiber cord is a colored layer that facilitates coating removal between a coating layer of an optical fiber and an overcoat layer of an optical fiber core. An optical jumper unit using an optical fiber cord.   The optical jumper unit according to any one of claims 1 to 7, wherein the optical fiber cord is provided with a stripe pattern decoration on an outer coating of the optical fiber cord to enable discrimination of the optical fiber cord. An optical jumper unit using a fiber cord.   The optical jumper unit according to any one of claims 1 to 7, wherein the optical fiber cord is provided with a tag capable of being identified by an optical fiber cord or a connector in order to enable discrimination of the optical fiber cord. An optical jumper unit using a fiber cord.

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