CH706936B1 - A method for creating a fiber optic link and using a splicer in such a process. - Google Patents

Abstract

The invention relates to a method for creating a fiber-optic connection between a first optical waveguide (21) and a second optical waveguide (22) associated therewith. The first and the second optical waveguides (21, 22) are each connected to a code which can be read out via the corresponding optical waveguide (21, 22), in particular in the form of a fiber Bragg grating (FBG1, FBG2). The further steps are reading the coding of the first optical waveguide (21), reading out the coding of the second optical waveguide (22), checking the assignment of the two read codings, connecting the two optical waveguides (21, 22) to one another.

Description

The present invention relates to a method for creating a fiber optic connection and the use of a splicer for temporary connection of an optical waveguide to a measuring means in such a method.

In the course of increased use of optical fibers for direct cabling of private households is generally spoken of Fiber-To-The-Home (FTTH). In such FTTH applications, however, the need arises that the operator of the fiber-optic network wants to specifically address the individual private connection, so as to unlock a single connection as required or to disconnect it from the data network.

For example, WO 96/31 022 A1 describes a fiber optic network between a service provider and an end user. The individual end users and also the nodes are designed with a reflector, which creates an individual reflection pattern. The service provider can thus verify the connection to each individual end user and ensure that the connection is working properly. If necessary, disruptions or network disruptions can be easily located. It is disadvantageous that in the event of an interruption in the network, a multiplicity of end users are affected by such an interruption. If a single user is to be disconnected from the network, this separation must necessarily take place in the last node, where a fiber optic cable separates into several individual lines. The service provider must therefore have access to the road distributor or house connection box.

It is also known that a service provider can provide a direct connection to an end user. Thus, for example, the central office of a service provider has a main distributor, which is connected via a fiber bundle with a plurality of individual glass fibers with the individual street distributors and further via a service connection box directly to a telecommunications outlet of the end user. The benefits of having such a direct connection between the service provider and the end user is that a failure affects only a single end user at a time. In addition, the service provider can connect the individual end user to the network directly in his main distributor or disconnect it if necessary. Access to the road distributor or house connection box for maneuvering connections is no longer necessary.

However, the production and management of such individual connections is complicated, since it is necessary to keep a precise record of which connection leads to which end user. In case of mechanical damage of the connection, for example when a trunk cable or a distribution cable is cut with one or more fiber bundles during excavation work, it is difficult to restore the connections between the individual fibers correctly.

It is an object of the invention to be able to correctly and easily perform the creation of such an individual connection, in particular to connect an address or code of the end user to the correct port of the main distributor of the service provider.

This object is achieved by the method defined in the independent claims. Further embodiments emerge from the dependent claims.

A method according to the invention for establishing a fiber-optic connection between a first optical waveguide and a second optical waveguide assigned thereto, in particular for establishing a continuous fiber-optic link between a central office of a service provider and an optical telecommunication socket of an end user in a building comprises the steps: Reading a first coding of the first optical waveguide by means of a measuring means, Reading out a second coding of the second optical waveguide by means of a measuring means, Checking the assignment of the two read codes, Connecting the first optical waveguide with the second optical waveguide.

In this case, the first optical waveguide is connected to a readable via the first optical fiber first coding or can be connected to such a coding. Also, the second optical waveguide is connected to a readable via the second optical waveguide second encoding or can be connected thereto. An exemplary coding is a fiber Bragg grating, which may be located directly in an end region of the fibers. It is also conceivable that the fiber Bragg grating is integrated in a connector of the optical telecommunications socket. Not only a single fiber Bragg grating is understood as a fiber Bragg grating, but also a fiber Bragg grating array, that is to say a combination of a plurality of fiber Bragg gratings, which are inscribed, for example, next to one another in an optical waveguide , As an alternative to a fiber Bragg grating, a thin film filter or reflective coating on a fiber end face or a combination of optical components such as prisms, lenses, etc. may also be used for encoding. The fact that in each case the assignment of the two read codes is checked before connecting the two optical fibers, it can be ensured that in each situation only two mutually associated optical waveguides are connected. This allows the correct assignment between the central office of the service provider and the telecommunication socket of the end user not only when first creating the fiber optic link, but also during maintenance after a fiber interruption. The connection of the two optical waveguides can be produced for example by means of a splice, mechanically or thermally, or else by a conventional plug connection.

For reading out the coding of the first and / or the second optical waveguide, in each case the measuring means can be connected to the first optical waveguide and / or to the second optical waveguide. In this case, the measuring means can read out the characteristic of the coding connected to the first optical waveguide or the second optical waveguide via a portion of a signal emitted by the measuring means, which is reflected by the encoding. It goes without saying that the order of reading out the codings of the two optical waveguides has no influence on the method. Likewise, it is conceivable that the coding of the first and the second optical waveguide is read out simultaneously with a suitable measuring means. Accordingly, a simultaneous connection between the measuring means and the two optical waveguides would be necessary. Characterized in that the coding of the optical waveguide can be read via the optical waveguide, it is possible that the coding is connected to one end of the optical waveguide, to which the service provider or an installer has no access. Accordingly, however, the coding can be read out at any point of the optical waveguide, in particular at a break in the fiber-optic link.

The measuring means can be connected by means of an optical fiber stub to the first optical waveguide and / or to the second optical waveguide. The use of a fiber optic stub allows on the one hand, that the measuring means is equipped with an example normalized connector interface to which an optical fiber stub, for example in the form of a pigtail, is connected to the measuring means. Should the optical fiber stub wear or become damaged, this optical fiber stub can be easily and inexpensively replaced without having to take the measuring equipment to a repair shop for maintenance purposes. The use of an optical fiber stub is also advantageous because, for example, by connecting the optical fiber stub or the measuring means to an optical fiber connected to a code to be read, the optical fiber stub can be worn and / or damaged. In particular, if a connection in the form of a thermal splice is created for the reading of the coding, a part of the optical fiber stub must be cut off when disconnecting the connection. As soon as the length of the optical fiber stub is no longer suitable for further connection to an optical waveguide, the optical fiber stub can be replaced.

For the connection of the measuring means to the first optical waveguide and / or to the second optical waveguide, an alignment mechanism of a splicer can be used. Conventionally, known splicing devices are equipped with an alignment mechanism which precisely aligns two clamped optical fiber ends and holds them ready for the subsequent splicing process. For example, the end of the optical waveguide stub to be connected can be clamped in a first receptacle of the alignment mechanism, for example in a V-groove, and the end of the first and / or second optical waveguide to be connected can be clamped in a second receptacle. Usually, the splicer will align the two optical fibers so that the light-guiding cores of the two optical fibers are aligned with each other in the X, Y and Z axes. Already by such an alignment, an optical connection is made, and the meter, which is connected to the optical fiber stub, can read the characteristic of the coding of the corresponding optical waveguide. Aligning with one another is sufficient for readout, and thermal splicing of the optical waveguides can be dispensed with. However, it is also conceivable that for certain applications, a thermal splice connection is preferred, so that triggered as in normal splicing operations of the arc and the two fibers of the optical waveguide and the fiber stub are welded together. As already mentioned above, the optical waveguide stub or the optical waveguide can be severed for the subsequent release of such a connection.

If the assignment of the two read out of the first and second optical waveguides codes is recognized as coincident, a splicer can be used in a conventional manner for connecting the two optical fibers. It is then a thermal splice, ie a welded joint between the two optical fibers, created. The connection of the two optical waveguides is thus produced as lossless as possible. Preferably, the same splicer is used for this purpose, which has already been used for connecting the optical waveguide to the measuring means. Alternatively, however, a connector can be made. This is particularly advantageous in the first installation, since then planned the connections and the corresponding connectors can be pre-assembled.

At least one of the two optical waveguides can be arranged in a fiber bundle. Accordingly, the step of reading out the coding to retrieve the mutually assigned and to be connected optical waveguide is to be repeated with a different optical fiber from the fiber bundle.

Another object of the present invention relates to the use of a splicer in a method as described above for the temporary connection of an optical waveguide to a measuring means. In this case, the measuring means has a fiber optic stub for connection to the optical waveguide. One end of the optical waveguide and one end of the optical fiber stub are aligned with each other by means of an alignment mechanism of the splicer. It is sufficient that the fiber ends of the optical fiber stub and the optical waveguide are only aligned and / or physically contacted with each other. A thermal splice, as it is usually made with a splicer, is not absolutely necessary, but can be done depending on the application. By means of such a temporary connection measuring means for various purposes can be connected to an optical fiber for a short time, without being extensively equipped with a connector in advance.

The measuring means can serve for reading a coding associated with an optical waveguide. Such coding is formed for example in the form of a fiber Bragg grating. However, other codings are conceivable.

On the basis of figures, which represent only exemplary embodiments, the invention is explained in more detail below: <Tb> FIG. 1: <SEP> A schematic representation of a FTTH network, and <Tb> FIG. 2: <SEP> is a schematic representation of an inventive use of a splicer.

Fig. 1 shows a schematic representation of an FTTH network. Starting from a central office CO of a service provider and a corresponding main distributor OMDF a trunk cable 12 can be seen, which leads from the main distributor OMDF to the road distributor DP. The trunk cable is usually a multiple cable or fiber bundle. Each of the individual optical fibers from the trunk cable is connected to an individual fiber Bragg grating FBG2. For the sake of simplicity, however, only a single fiber Bragg grating is shown. These fiber Bragg gratings FBG2 allow the individual identification of the individual fibers of the parent cable 12, which can be read out, for example, at the road distributor DP.

About a distribution cable 10, which also includes a plurality of optical fibers, the road distributor DP is connected to a service connection box BEP a building 1. In the house connection box BEP now the individual optical fibers of the distribution cable 10 are divided into individual Inhousekabel 2. In each case leads a in-house cable 2 from the house connection box BEP to a telecommunications socket OTO an end user or a single apartment. In order to be able to individually address the individual end user, the corresponding in-home cable 2 is connected to a coding in the form of a fiber Bragg grating FBG1. Again, a fiber Bragg grating is shown only for an end user for the sake of simplicity. It goes without saying that each end user is assigned a corresponding coding in the form of a fiber Bragg grating. This fiber Bragg grating can be placed directly in the corresponding home cable 2 or in a connector of the indoor cable 2, be installed in the telecommunications socket OTO or in a coupling element of the telecommunications socket OTO. Starting from the telecommunication socket OTO of the end user is connected to a connection cable 3, a connection box 4 with the optical telecommunications socket OTO. The connection box 4, for example, converts an optical data signal into an electrical signal. Thus, the end user can connect via a conventional internal LAN a telephone 6, a computer 7, a TV set 8 and other appropriately equipped devices. Shown in FIG. 1 is the LAN cabling as Ethernet cabling 5.

In the case of an initial connection of an end user to the Central Office CO of the service provider, an optical fiber from the distribution cable 10 is identified, for example in house connection box BEP, which with the corresponding coding in the form of a fiber Bragg grating FBG2 on the road distribution box DP and the Master cable 12 is connected. Also identified is the optical fiber to be connected or the corresponding home cable 2, which leads to the corresponding end user or to its coding in the form of the fiber Bragg grating FBG1. As soon as the two optical waveguides which are to be assigned to one another are identified with their corresponding codes, these can be connected to one another in the house connection box BEP. Such a connection usually takes place with a splicer and a thermal splice. It is also conceivable, however, a plug connection.

Fig. 2 shows the schematic use of a splicer 20 for connecting a first optical waveguide 21 with a second optical waveguide 22. In this case, the first optical waveguide 21 is connected to an end user or rather to an optical telecommunication socket OTO of the end user. At the same time, the optical waveguide 21 is connected to a unique coding in the form of a fiber Bragg grating FBG1. The optical waveguide 22 is connected either directly or for example via one or more road distributors DP (see FIG. 1) to a main distributor OMDF of a central office CO of a service provider. The optical waveguide 22 is also connected to an individual coding in the form of a fiber Bragg grating FBG2. In the illustration according to FIG. 2, both optical waveguides 21 and 22 are each arranged in a fiber bundle 14. It goes without saying that each optical fiber of the two fiber bundles 14 are each connected to an individual coding in the form of a fiber Bragg grating. For the sake of simplicity, however, only one fiber Bragg grating is ever shown.

To determine the correct light waveguides 21 and 22 to be connected to each other, these are temporarily connected by means of a splicer 20 with a measuring means 25. On the measuring means 25, an optical fiber stub 28 is connected, which is clamped with its free end in the splicer 20 and in a first recording of an alignment mechanism of the splicer 20. In a second recording of the alignment mechanism of the splicer 20, for example, the optical waveguide 21 is clamped. Now, the ends of the optical fiber stub 28 and the optical fiber 21 can be aligned with each other in the usual way. For this purpose, the splicer has a display 23, which enlarges the two ends, so that a precise alignment is made possible. It does not matter if this alignment is done automatically or done manually. Once the two ends are aligned, a signal 26 may be emitted from the measuring means which are transmitted along the optical fiber route through the optical fiber stub 28 over the aligned ends of the optical fiber stub 28 and the optical fiber 21, over the optical fiber 21 to the optical telecommunications socket OTO , Since the optical waveguide 21 is connected to a fiber Bragg grating FBG1, part of the signal 26 is reflected at this fiber Bragg grating FBG1 and, as a reflected portion 27 of the signal 26, again finds the way back along the optical waveguide path to the measuring means 25 , The measuring means 25 will accordingly recognize and display the read-out coding on the basis of the reflected portion 27 of the signal 26. If the displayed coding is the desired coding of the optical waveguide to be connected or of the end user to be connected, the optical waveguide 21 can be marked accordingly by a fitter. However, if the read encoding does not correspond to the correct value, then another optical waveguide can be pulled out of the fiber bundle, connected in the receptacle of the splicer 20 to the optical waveguide stub 28, and the coding read out again. This step is then repeated until the read coding corresponds to the coding which is assigned to the end user to be connected.

In a similar manner, the second optical waveguide 22 is now connected via the splicer 20 to the measuring means 25. The measuring means 25 in turn sends out a signal 26, which reaches the main distributor OMDF of the service provider via the resulting optical waveguide route. The optical waveguide 22 is in turn equipped in the region of the main distributor OMDF with a fiber Bragg grating FBG2, so that the signal 26 can in turn be partially reflected and correspondingly re-evaluated in the measuring means 25. Once again, the evaluation of the coding of the optical waveguide 22 with different fibers of the fiber bundle 14 is repeated until the corresponding optical waveguide is identified. It goes without saying that the order of reading out the coding of the optical waveguides (21, 22) has no influence on the method.

Subsequently, the fiber stub 28 is removed from the splicer 20 and the two previously identified optical waveguides 21 and 22 each clamped in the splicer 20. There is a conventional splicing process, for example, a thermal splicing process, wherein the orientation of the two optical waveguides 21, 22 in the display 23 of the splicer 20 can be checked.

Claims (7)

1. A method for establishing a fiber optic connection between a first optical waveguide (21) and a second optical waveguide (22) associated therewith, in particular for establishing a continuous fiber optic link between a central office (CO) and an optical telecommunication socket (OTO) in a building ( 1), wherein the first optical waveguide (21) is connected or connected to a first coding which can be read out via the first optical waveguide (21), in particular in the form of a first fiber Bragg grating (FBG1), wherein the second optical waveguide (22) is connected or connected to a second coding which can be read out via the second optical waveguide (22), in particular in the form of a second fiber Bragg grating (FBG2), comprising the steps - reading the first coding of the first optical waveguide (21) by means of a measuring means (25), - reading the second coding of the second optical waveguide (22) by means of a measuring means (25), Checking the assignment of the two read codes, - Connecting the first optical waveguide (21) with the second optical waveguide (22). 2. The method according to claim 1, characterized in that for reading out the coding of the first and / or the second optical waveguide (21, 22) in each case the measuring means (25) to the first optical waveguide (21) and / or to the second optical waveguide (22 ), wherein the measuring means (25) has the characteristic of the coding connected to the first optical waveguide (21) or the second optical waveguide (22) via a component (27) reflected by the encoding of a signal (26) emitted by the measuring means (25). reads. 3. The method according to claim 2, characterized in that the measuring means (25) by means of an optical fiber stub (28) to the first optical waveguide (21) and / or to the second optical waveguide (22) is connected. 4. The method according to claim 3, characterized in that for the connection of the measuring means (25) to the first optical waveguide (21) and / or to the second optical waveguide (22) an alignment mechanism of a splicer (20) is used. 5. The method according to any one of claims 1 to 4, characterized in that for connecting the first optical waveguide (21) to the second optical waveguide (22), a splicer (20) is used. 6. The method according to any one of claims 1 to 5, characterized in that at least one of the two optical waveguides (21, 22) in a fiber bundle (14) is arranged and the step of reading the codes until finding the mutually associated and to be connected optical fibers (21, 22) each with another optical fiber from the fiber bundle (14) is repeated. 7. Use of a splicing device (20) for connecting an optical waveguide (21, 22) to a measuring means (25) in a method according to one of claims 1 to 6, wherein the measuring means (25) comprises a fiber optic stub (28) for connecting the optical waveguide (20). 21, 22), characterized in that one end of the optical waveguide (21, 22) and one end of the optical fiber stub (28) are aligned by means of an alignment mechanism of the splicer (20).