JP2009103513A - Dummy fiber apparatus, and measuring method of optical characteristic of optical fiber to be measured by using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce probability of a damage accident of an optical fiber during optical fiber construction work or the like. <P>SOLUTION: A dummy fiber apparatus A is equipped with a case 10 storing an optical fiber coil formed by winding in a coil shape, an optical fiber cable wherein each optical connector is mounted respectively on both fiber ends; and a pair of optical adapters 11 provided respectively in the case 10 in such a manner that whose one connection part is arranged in the case 10 and whose other connection part is arranged out of the case 10 respectively, wherein each optical connector mounted respectively on each fiber end of the optical fiber coil is connected to one connection part. In the dummy fiber apparatus A, a suspension strap 30 is fitted to the case 10. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a dummy fiber device used for OTDR (Optical Time Domain Reflectometry) measurement and the like and a method for measuring optical characteristics of an optical fiber to be measured using the same.

  In OTDR measurement for detecting and evaluating an optical fiber failure location, a dummy fiber device is provided between the optical fiber to be measured and the OTDR measurement device so that the failure location can be searched.

Such a dummy fiber device is composed of, for example, a hollow coil as disclosed in Patent Document 1 and a bobbin winding coil disclosed in Patent Document 2.
JP 2007-127812 A JP 2005-181791 A

  An object of the present invention is to reduce the possibility of an optical fiber breakage accident during measurement of optical characteristics of an optical fiber to be measured in optical fiber construction or the like.

The dummy fiber device of the present invention includes a housing containing an optical fiber coil in which an optical fiber core wire having an optical connector attached to each of both fiber ends is wound in a coil shape,
Each of the housings is provided such that one connection portion is disposed in the housing and the other connection portion is disposed outside the housing, and the one connection portion is provided at a fiber end portion of the optical fiber coil. A pair of optical adapters to which the attached optical connectors are connected;
With
A hanging strap is attached to the housing.

The method for measuring the optical characteristics of the optical fiber to be measured according to the present invention includes:
A housing containing an optical fiber coil in which an optical fiber core wire having an optical connector attached to each of both fiber ends is wound in a coil; and
Each of the housings is provided such that one connection portion is disposed in the housing and the other connection portion is disposed outside the housing, and the one connection portion is provided at a fiber end portion of the optical fiber coil. A pair of optical adapters to which the attached optical connectors are connected;
Using a dummy fiber device provided with a predetermined optical measuring instrument,
Holding the dummy fiber device so that the housing is in a suspended state;
An optical connector attached to the fiber end of the optical fiber extending from the measuring instrument is connected to the connection portion of one optical adapter outside the housing of the dummy fiber device, and the optical fiber to be measured is connected to the connection portion of the other optical adapter. Connecting optical connectors respectively attached to the fiber ends of
Measuring predetermined optical characteristics of the optical fiber to be measured by the optical measuring instrument;
It is provided with.

  According to the present invention, by holding the dummy fiber device so that the housing is in a suspended state, the housing is held in a movable state from side to side. Even if something is caught in the optical fiber during the measurement of the characteristics, the extra length is obtained, and as a result, the possibility of an optical fiber breakage accident can be reduced.

  Hereinafter, embodiments will be described in detail.

  1 to 7 show a dummy fiber device A according to this embodiment. The dummy fiber device A is interposed between the measuring instrument and the optical fiber to be measured when measuring the optical characteristics of the optical fiber.

  In this dummy fiber device A, the housing 10 constitutes the device body, and the optical fiber coil 20 is accommodated in the housing 10.

  The housing 10 is formed in, for example, a vertically long rectangular flat plate made of hard resin, and includes a shallow dish-shaped member 10a and a lid member 10b that closes the opening with a locking structure. The housing 10 is formed to have a length of 60 to 150 mm, a width of 40 to 100 mm, and a thickness of 10 to 30 mm, for example.

  FIG. 8 shows the optical fiber coil 20 housed in the housing 10.

  The optical fiber coil 20 has a structure in which a coil body 21 made of an optical fiber core wire is provided on a substrate 22 and covered with a covering sheet 23 and packed.

  The coil body 21 is formed in a cylindrical shape by winding an optical fiber core wire in a coil shape. For example, the coil body 21 has an outer diameter of 35 to 95 mm, an inner diameter of 15 to 60 mm, and a height of 5 to 28 mm.

  In the optical fiber core wire forming the coil body 21, a quartz or resin optical fiber having a core and a clad is covered with a resin coating layer. The optical fiber is composed of, for example, a 1.3 μm SMF (Single Mode Fiber), an EDF (Erbium Doped Fiber), a DCF (Dispersion Compensating Fiber), or a 1.55 μm DSF (Dispersion Shifted Fiber). It is formed to 1000 m.

  In the coil main body 21, a bundle of optical fiber core wires is bound by a binding material 24 at intervals in the circumferential direction. The binding material 24 is composed of, for example, a polytetrafluoroethylene tape having self-bonding properties.

  The substrate 22 has a structure in which an adhesive layer is provided on a rectangular flexible resin sheet such as polyethylene terephthalate (PET). The substrate 22 is formed to have a length of 55 to 145 mm, a width of 38 to 98 mm, and a thickness of 5 to 28 mm, for example.

  The covering sheet 23 is made of, for example, a heat flexible resin film such as polyethylene (PE). The covering sheet 23 has a thickness of 0.02 to 0.2 mm, for example.

  A pair of lead wires 25 extending from the coil body 21 to both ends of the fibers are led out of the substrate 22. An optical connector 26 is attached to the fiber end that is the tip of each lead wire 25. Examples of the optical connector 26 include an FC connector (JIS C5970 (F01)), an SC connector (JIS C5973 (F04)), a D-type connector (JIS C5980 (F11)), an MT connector (JIS C5981 (F12)), and an MPO. Examples include connectors (JIS C5982 (F13)), MU connectors (JIS C5983 (F14)), LC connectors (IEC 61754-20), and the like.

  In this dummy fiber device A, a pair of optical adapters 11 are arranged side by side symmetrically in the center of the upper side surface of the housing 10.

  Each of the pair of optical adapters 11 has one connection portion disposed in the housing 10 and the other connection portion disposed outside the housing 10, and the connection portion outside the housing 10 is used when not in use. A cap 12 is detachably fitted. The pair of optical adapters 11 has a configuration in which both connection portions in the housing 10 correspond to the optical connector 26 attached to the fiber ends of both lead wires 25 of the coil body 21, and one connection portion includes a coil. An optical connector 26 attached to the fiber end of one lead wire 25 of the main body 21 is connected to the optical connector 26 attached to the fiber end of the other lead wire 25 of the coil main body 21. Each is connected. The pair of optical adapters 11 are attached to the optical connector 41 attached to the fiber end portion of the optical fiber 40 and the fiber end portion of the optical fiber 50 to be measured, both connection portions outside the housing 10 extending from the measuring instrument. Although it has a configuration corresponding to the optical connector 51, the connecting portion inside the housing 10 and the connecting portion outside the housing 10 may be the same or different. Examples of the optical adapter 11 include FC-FC type, SC-SC type, MU-MU type, LC-LC type, FC-SC type, SC-LC type, and SC-ferrule type.

  In this dummy fiber device A, a hanging strap 30 is attached to the housing 10.

  The strap 30 includes a strap body 31 and a strap attachment 32 that attaches the strap body 31 to the housing 10.

  The strap body 31 is formed into an annular string-like body or band-like body by a fiber material. The strap main body 31 has a caulking tool 33 attached slightly above the lower end portion, and a small ring portion 31a is formed at the lower end portion below it. For example, the strap body 31 is formed to have a circumference of 40 to 160 mm and a width of 5 to 20 mm, and may have some elasticity. The strap body 31 may be provided with an adjustment tool for adjusting the suspension length, and a weak member for breaking and opening the ring when an excessive force is applied. It may be done.

  The strap attachment 32 includes a pair of linear members 34, a cylindrical member 35, and a lower annular member 36 on the housing 10 side, an attaching / detaching member 37 on the strap body 31 side, and an upper annular member 38.

  Each of the pair of linear members 34 is fixed so that the lower end is sandwiched between the housing 10 and the optical adapter 11, extends inwardly upward, and the upper end is fixed to the lower portion of the cylindrical member 35. Thereby, the cylindrical member 35 is positioned above the center between the pair of optical adapters 11. A through hole is formed in the upper portion of the cylindrical member 35 so as to extend in the lateral direction, and a lower annular member 36 in which a metal wire is formed in an annular shape is inserted into the through hole.

  The upper annular member 38 is passed through the small ring portion 31a of the strap body 31, and a through hole is formed in the lower portion of the member so as to extend in the vertical direction. The shaft-shaped member of the detachable member 37 is formed in the through hole. The upper part of the main body 37a is inserted and the tip is caulked. The detachable member 37 has a member main body 37a formed in a C shape and engaged with the lower annular member 36, and an opening opening / closing member 37b for opening and closing the opening of the member main body 37a is provided. One end of the opening / closing member 37b is rotatably supported by the upper opening end of the member main body 37a, and the other end is urged so as to contact the lower opening end.

  In the dummy fiber device A having the above configuration, the strap 30 is attached to the housing 10, so that the portability is excellent. Further, since the upper annular member 38 or the lower annular member 36 is interposed, the casing 10 constituting the apparatus main body can be swung left and right around the upper annular member 38 or the lower annular member 36. Further, the attachment structure of the detachable member 37 to the upper annular member 38 is configured to be rotatable about the upper portion of the member main body 37a of the detachable member 37. Further, the opening / closing member 37b is provided in the member main body 37a of the detachable member 37 with which the lower annular member 36 is engaged, and the strap attachment 32 can be divided into the casing 10 side and the strap main body 31 side. The strap body 31 is configured to be detachable.

  Next, a method for measuring predetermined optical characteristics of the optical fiber to be measured using the dummy fiber device A will be described. As a specific case, for example, measurement of transmission loss and connection loss of an optical fiber to be measured using an OTDR device as a measuring instrument can be cited.

  First, as shown in FIG. 9, the strap 30 is hung around the neck, and the dummy fiber device A is held so that the housing 10 is in a suspended state. Here, the suspension radius (the length from the suspension center to the mounting end of the housing 10) is preferably 20 to 80 cm, and preferably about 50 cm from the viewpoint of measurement workability and shock absorption. Is more preferable.

  Next, the cap 12 is removed from the connection portion of the one optical adapter 11 outside the housing 10 of the dummy fiber device A, and the optical connector 41 attached to the fiber end portion of the optical fiber 40 extending from the measuring instrument is connected thereto. Moreover, the cap 12 is removed from the connection portion of the other optical adapter 11, and the optical connector 51 attached to the fiber end portion of the optical fiber 50 for measurement connected to the optical fiber to be measured is connected thereto. The optical fibers 40 and 50 are actually optical fiber cores provided with polyamide resin coating or UV curable resin coating, or cords having a diameter of 1.1 to 3.0 mm provided with tensile fibers. It is a form. Further, at this time, it is preferable that any of the optical connectors 41 and 51 is cleaned by wiping its connection end face. Thereby, the damage accident of the end surface of the optical connectors 41 and 51 by dust, dust, etc. can be prevented beforehand. Therefore, the dummy fiber device A may be one to which a connector end face cleaning tool is attached.

  Then, predetermined optical characteristics of the optical fiber to be measured are measured by the optical measuring instrument.

  According to the measurement method as described above, the housing 10 is held in a movable state from side to side by holding the dummy fiber device A so that the housing 10 is in a suspended state. Even when something is caught on the optical fibers 40 and 50 when measuring the optical characteristics of the optical fiber to be measured, the optical fibers 40 and 50 have a surplus length. As a result, the optical fibers 40 and 50 may be damaged. Can be reduced. For example, as shown in FIG. 10, the hanging radius (the length from the hanging center to the mounting end of the housing 10) is 0.5 m, the mass of the housing 10 is 0.1 kg, and the optical fiber extends from the measuring instrument. Alternatively, even when the length of the optical fiber to be measured is 2.4 m and something is caught on the optical fiber and is pulled 0.4 m, the strap 30 is pulled and the housing 10 is 60 in the vertical direction. The force acting on the optical fiber is about 1.94 N by rotating about °. This is much smaller than the lateral allowable pulling force 4.9 N of the optical connector shown in Table 4 of JIS C5974. Furthermore, if the strap 30 has some stretchability, the pulling force can be reduced to a slight extent.

  As a means for obtaining the same effect, it is conceivable to connect an optical fiber curl cord disclosed in JP-A-2005-3821, etc., to an optical fiber extending from a measuring instrument or an optical fiber to be measured. According to the above method, there is no need to use such an expensive one.

  In the present embodiment, the casing 10 is formed in a flat plate shape, but is not particularly limited thereto, and may be configured in other shapes.

  In the present embodiment, the pair of optical adapters 11 are arranged side by side on the same side surface portion of the housing 10, but the present invention is not limited to this, and the configuration is provided on different side surface portions. There may be. However, the configuration of the present embodiment is preferable from the viewpoint of workability.

  In the present embodiment, the strap 30 is attached to the housing 10 so that the side surface portion on which the pair of optical adapters 11 is provided becomes the upper surface when the suspension is used. Instead of this, a configuration in which the strap 30 is attached to the housing 10 such that the side surface provided with the pair of optical adapters 11 is the lower surface may be used. However, the configuration of the present embodiment is preferable from the viewpoint of workability.

  Further, in this embodiment, the strap 30 is hung around the neck and the dummy fiber device A is held so that the housing 10 is in a suspended state. You may hang it.

  INDUSTRIAL APPLICABILITY The present invention is useful for a dummy fiber device used for measuring optical characteristics of an optical fiber and the like and a method for measuring optical characteristics of an optical fiber to be measured using the same.

It is a front view of the dummy fiber apparatus which concerns on this embodiment. It is a right view of the dummy fiber apparatus which concerns on this embodiment. It is a rear view of the dummy fiber apparatus which concerns on this embodiment. FIG. 2 is a partially enlarged view of A-A ′ in FIG. 1. FIG. 3 is a partial enlarged view of B-B ′ in FIG. 2. FIG. 4 is a partial enlarged view of C-C ′ in FIG. 3. FIG. 5 is an enlarged perspective view of a portion D-D ′ in FIG. 4. It is a perspective view of an optical fiber coil. It is explanatory drawing which shows the measuring method of an optical characteristic. It is explanatory drawing which shows the effect | action of the measuring method of an optical characteristic.

Explanation of symbols

A dummy fiber device 10 housing 11 optical adapter 20 optical fiber coils 26, 41, 51 optical connector 30 strap 40 optical fiber

Claims (3)

A housing containing an optical fiber coil in which an optical fiber core wire having an optical connector attached to each of both fiber ends is wound in a coil; and
Each of the housings is provided such that one connection portion is disposed in the housing and the other connection portion is disposed outside the housing, and the one connection portion is provided at a fiber end portion of the optical fiber coil. A pair of optical adapters to which the attached optical connectors are connected;
A dummy fiber device comprising:
A dummy fiber device, wherein a hanging strap is attached to the housing. In the dummy fiber device according to claim 1,
The casing is formed in a flat plate shape, the pair of optical adapters are arranged side by side on the same side surface of the casing, and the strap is provided with the pair of optical adapters when suspended. A dummy fiber device, wherein the dummy fiber device is attached to the housing such that the side surface portion becomes the upper surface. A housing containing an optical fiber coil in which an optical fiber core wire having an optical connector attached to each of both fiber ends is wound in a coil; and
Each of the housings is provided such that one connection portion is disposed in the housing and the other connection portion is disposed outside the housing, and the one connection portion is provided at a fiber end portion of the optical fiber coil. A pair of optical adapters to which the attached optical connectors are connected;
A method for measuring a predetermined optical characteristic of an optical fiber to be measured by a predetermined optical measuring instrument using a dummy fiber device comprising:
Holding the dummy fiber device so that the housing is in a suspended state;
An optical connector attached to the fiber end of the optical fiber extending from the measuring instrument is connected to the connection portion of one optical adapter outside the housing of the dummy fiber device, and the optical fiber to be measured is connected to the connection portion of the other optical adapter. Connecting optical connectors respectively attached to the fiber ends of
Measuring predetermined optical characteristics of the optical fiber to be measured by the optical measuring instrument;
A measurement method characterized by comprising:

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