JP5003969B2 - Optical connection member - Google Patents

Description

  The present invention relates to an optical connection member used for connecting a large number of optical fibers in an optical wiring board or the like forming an optical wiring network.

  An optical transmission system communicates by transmitting optical signals to each other by laying optical cables composed of a number of optical fibers between a station and another station, between a station and a subscriber terminal, or in a house or building. System. A large number of optical fibers are optically connected to other stations and subscribers' homes using optical connection members on the optical distribution board in the station, etc. In order to specify the connected optical fiber when installing or changing connections. A heart contrast is performed.

  For example, as disclosed in Patent Document 1, an optical coupler is provided for each of the optical fiber cores connected to the optical wiring board, and the optical coupler is selected to form the optical fiber core. Disclosed is a method for performing a contrast control by entering visible light (or control light) and diffusing and transmitting visible light through an optical connector cap provided at a terminal on the terminal side of the optical fiber core. Yes.

  Patent Document 2 discloses an IR filter that converts control light (not visible light) that has entered the optical fiber cord into a cover of a connection adapter from which one of the optical connectors is removed, and converts the control light into visible light. There is disclosed a method in which such an optical element is incorporated, and when contrast light hits the optical element, it is converted to visible light and visually contrasted. Further, Patent Document 2 also discloses a method of detecting the reference light that is bent at the bending point by bending the optical fiber cord when the optical connector is not removed.

Further, in Patent Document 3, a notch or an opening through which visible light leaked from the optical connector leaks to the outside is formed in the adapter that connects the optical connectors, and a predetermined optical communication cable is visually recognized. A method is disclosed.
JP 2000-88704 A Japanese Patent No. 3363383 JP 2007-226112 A

  According to the above Patent Documents 1 and 2, the control light is directly incident on the optical fiber core via the optical coupler, and the control light is diffused and transmitted through the optical connector cap on the terminal side. Can be easily done. However, many optical fiber core wires (or optical fiber cords) and optical connectors are densely congested in optical wiring facilities in a station or the like with high density. For this reason, for fault detection such as rewiring or disconnection with jumper wires, identification means such as barcodes are also attached to the optical fiber core wires. Since the periphery in the board is dark, the above-mentioned core line contrast operation is not easy. As a result, it takes time to identify the port to be subjected to the control of the cords, and other optical connectors in communication may be erroneously inserted or removed.

  In addition, the above-described core wire contrast in Patent Documents 1 and 2 is performed for a non-communication optical fiber core wire that does not have signal light. Such work is required. The above-mentioned Patent Document 2 also shows an example in which the optical fiber cores are compared without removing the optical connector. However, the optical fiber cores are bent to cause leakage light. Therefore, there is a problem that the optical fiber core wire during other communication is also bent, causing a loss variation with respect to the steady optical communication and causing a communication abnormality.

  Patent Document 3 discloses detecting visible light leaking from an optical connector, but does not disclose details of the visible light leakage mechanism and its visibility. However, the leakage of visible light is caused by slight axial misalignment between optical fibers at the ferrule end portion of the optical connector that is abutted at the intermediate position of the connection adapter, and this leaked light is notched on both end portions of the adapter. It is assumed that it is visible through the opening. When visible light leaks due to the axial misalignment between the butted portions of the optical fibers, the amount of leaked light varies depending on the degree of axial misalignment, and there is a risk that constant visibility may not be obtained.

  Further, the visible light visible at both ends of the connection adapter has a high light intensity on the downstream side of the light and a low light intensity on the upstream side of the light. For this reason, even if it is possible to visually recognize the leaked light on the light emitting side (downstream side) of the connection adapter, it is assumed that the leaked light is weak on the light incident side (upstream side) of the connection adapter and is difficult to view. . For this reason, it may be difficult to compare the cores with the optical fiber cores connected to the light incident side of the connection adapter attached with the panel interposed therebetween.

  Furthermore, in Patent Document 3, leakage light does not occur unless both optical connectors are connected to the connection adapter. Therefore, when the optical connector is not connected to the adapter, the optical connector is identified from the outer surface of the housing. It is not possible to look into the ferrule end of the optical connector. Further, since the existing connection adapter provided in the optical wiring board cannot detect leaked light, there is a problem that it must be used in place of a connection adapter capable of detecting leaked light.

  The present invention has been made in view of the above-described circumstances, and makes it easy to perform a cord comparison in either a state where the optical connector is disconnected or an optical communication state without disconnecting the optical connector. An object of the present invention is to provide an optical connection member capable of satisfying the requirements.

An optical connection member according to the present invention is an optical connection member that detachably connects optical fibers used for optical signal transmission, and has a width W that allows visible light to leak into the optical fiber when the optical fiber is attached to a ferrule. Is provided with a light derivation mechanism that provides a slit having an angle θ of 4 ° to 10 ° intersecting with the ferrule axis and that emits part of visible light input into the optical fiber to the outside. In addition, said light derivation | leading-out mechanism can be provided in either the optical connector or the optical connection adapter which connects optical connectors.

  According to the present invention, it is possible to perform the contrast control without connecting the optical connector to the connection adapter or the like, but it is possible to perform the contrast control while the optical connector is connected and the transmission state of the optical signal is maintained. . In this case, it can be easily performed only by visually recognizing visible light leaking outside the optical connector without adversely affecting optical communication. Also, other optical connectors installed in multiple stages on the downstream side can be subjected to the control of the core wires, thereby reducing the erroneous insertion / removal of the optical connector and improving the workability.

  Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram for explaining an example of a core line control system according to the present invention, and refers to the system example disclosed in Patent Document 1. In the figure, 1 is an optical transmission device, 2 is a star coupler rack, 3 is an optical cable termination rack, 4 (4a to 4d) is an optical cable (fiber optic cable), 5 (5a to 5d) is a subscriber terminal, 6 ( 6a to 6d) are optical fibers (branching optical fibers), 7a to 7d are jumper wires, 8 and 9 are optical connection members, 10a and 10b are optical wiring boards, and 11 (11a to 11d) are optical branching modules (optical couplers). , 12 and 13 are branch optical fibers, 14 is an optical switch, 15 is a control device, 16 is a visible light source, 17 is an optical pulse tester, and 18 is a light source for loss test.

  The optical transmission device 1 (OLT) sends out signal light to be transmitted to each of the subscriber terminals 5 (ONT) to the star coupler rack 2 via the optical fiber 6. In the star coupler rack 2, in order to distribute the signal light from the optical transmission apparatus 1 to a large number of subscriber terminals 5, the optical fiber 6 is branched into multiple branch optical fibers 6a to 6d by the star coupler 2a (in FIG. 1, four branches). The signal light is distributed and transmitted to each of them. The output ends of the branched optical fibers 6a to 6d are connected to the optical connection member 8 disposed at a high density on the optical wiring board 10a. In order to simplify the description, the number of optical fibers is four, but in actuality, the optical fibers are composed of several tens to several hundreds.

  The signal light from the star coupler rack 2 is sent to the optical fiber core wire of the optical cable termination rack 3 through the jumper wires 7a to 7d. The optical cable termination 3 includes an optical wiring board 10b, an optical branching module 11, and an optical switch 14. In the optical wiring board 10b, a large number of optical connection members 9 for receiving the signal light from the optical transmission device 1 through the jumper wires 7a to 7d are arranged with high density. The optical connection members 8 and 9 used in the present invention refer to a form in which an optical connector and an optical connector are connected, and a form in which the optical connector is connected through a connection adapter.

  The optical connection member 9 is connected to the input ends of the optical fiber cores 4a to 4d for sending the received signal light to the subscriber terminal 5 side. The optical branching module 11 has a large number of optical couplers 11 a to 11 d and is provided on the respective laying paths of the optical fiber core wires 4 a to 4 d of the optical cable 4. Each of the optical couplers 11 a to 11 d includes, for example, two branch optical fibers 12 and 13, and a connection is selected by the optical switch 14.

  For example, when visible light is sent from the optical fiber 11a to the branch optical fiber 12, the visible light is transmitted toward the subscriber terminal 5a via the optical fiber 4a. Is done. On the other hand, when visible light is transmitted from the visible light source 16 to the branch optical fiber 13, visible light is transmitted toward the optical connecting member 9 via the optical fiber core 4a. The selection of the branch optical fibers 12 and 13 is performed by the optical switch 14 controlled by the control device 15. The optical switch 14 is also used for selecting the optical pulse tester 17 for transmitting the pulsed light and the loss test light source 18 for testing the transmission loss, in addition to selecting the transmission of visible light for contrast control. Used.

  As the visible light source 16, a light source that emits visible light (400 nm to 750 nm) can be used. It is desirable to use red laser light of 600 nm or more from a red laser light source because red light is relatively easy to identify with respect to the optical connecting member and has high light intensity. The light source may be a light source other than laser light. Further, since visible light transmitted into an optical fiber has a transmission loss larger than that of a wavelength band (1.31 μm, 1.55 μm) used for signal light for information transmission, an optical switchboard (for example, several tens to It is suitable for use as a core wire contrast by the optical connecting members 8 and 9 installed at a distance of several hundred meters.

  In addition, the above-mentioned core line contrast can be performed, for example, in an optical wiring in a building or house where the laying distance of the optical fiber is relatively short, but it is also performed between the station and a large number of subscriber terminals 5. Can do. It should be noted that optical cable laying work or the like for the subscriber terminal 5 can be handled by carrying the test device to the vicinity of the construction site. Further, when the distance between the cores becomes longer, it is possible to cope with the problem by using a visible light source having a high optical power. The optical pulse tester 17 sends pulsed light to the optical fiber cores 4a to 4d, detects backscattered light accompanying this, and performs an ODTR test. Further, as the loss test light source 18, for example, a light source of 1.65 μm band can be used, and a loss test of the optical transmission path to the subscriber terminal 5 can be performed.

  In the above-described core wire contrast system, the core wire contrast can be performed on the subscriber terminal 5, but an optical distribution board in which a large number of optical fiber core wires and a large number of optical connection members 8 and 9 are arranged. Often performed at 10a and 10b. In contrast, for example, the optical fiber core 4a to be compared with the optical switch 14 and the branch optical fiber 13 are selected to transmit light (for example, red laser light) transmitted from the visible light source 16. Suppose that In this case, the visible light is transmitted to the branch optical fiber 13 of the optical coupler 11a, is incident on the optical fiber core 4a from the optical coupler 11a, and is directed toward the optical connection member 9 provided on the transmission device 1 side. Sent out.

  In the present invention, when the optical fiber connector of the optical connecting member 8 or 9 is used for the optical fiber line contrast, it is possible to perform the optical fiber line contrast while the optical connector is removed. I can do it. Specifically, the optical connectors or connection adapters of the optical connecting members 8 and 9 are provided with a light deriving mechanism for deriving visible light transmitted into the optical fiber core to the outside, and light is emitted from this light deriving mechanism. Contrast is performed by visually recognizing visible light.

  2 and 3 are views for explaining an optical connecting member according to the present invention. FIG. 2 (A) is a view for explaining the outline of the optical connector, FIG. 2 (B) is a view showing its appearance, and FIG. (B) is a figure explaining the slit which leaks visible light. In the figure, 20 is an optical connector, 21 is an optical fiber core wire, 21a is a glass fiber, 22 is a ferrule, 23 is a ferrule holder, 24 is a connector housing, 25 is a spring, 26 is a window, 27 is a slit, and 28 is a slit. Show boots.

  As shown in FIG. 2A, the basic structure of the optical connector 20 is the same as a general optical connector structure. For example, an optical fiber core wire 21 (or an optical fiber cord) is provided in the ferrule 22. The glass fiber ends are removed and the glass fiber ends are inserted and bonded together. The ferrule 22 is held by a ferrule presser 23 and is mounted on the connector housing 24 while being urged in the axial direction by a spring 25 or the like. The lead-out portion of the optical fiber core wire 21 is protected by a boot 28 made of a resilient material such as rubber. Further, as shown in FIG. 2B, the optical connector has an external shape in which a latch lever 24a for operating insertion / extraction of the optical connector 20 is integrally provided in the connector housing 24, and the ferrule 22 extends from the tip of the connector housing 24. Is configured to protrude slightly.

  The optical connector 20 of the optical connecting member according to the present invention leaks a part of visible light transmitted together with signal light to the optical fiber core wire 21 into the optical connector 20 and releases the leaked visible light to the outside of the optical connector. It features a light-emitting configuration. The leakage of visible light in the optical fiber into the optical connector 20 can be realized by providing a slit 27 in the glass fiber 21 a mounted in the ferrule 22. Details of the slit 27 will be described later.

  Visible light leaked into the optical connector 20 is emitted to the outside of the optical connector 20 through a light derivation mechanism such as a window portion 26 provided in or near the portion where the slit 27 is located, whereby the optical fiber core 21. Can be identified. The window portion 26 is formed so that visible light leaking into the optical connector 20 reaches the outer surface of the optical connector housing 24. For example, the window portion 26 is formed in a form in which a plurality of small window holes are provided on the housing surface of the optical connector. can do. Further, the remaining visible light that is not leaked passes through the optical connector 20 and is sent to the downstream optical connector. Therefore, when the above optical connector is used on the downstream side, the optical fiber core wire 21 can be similarly identified.

  As shown in FIG. 2 (B), visible light emitted through the window portion 26 can be easily visually confirmed from the outside by causing the exit portion of the window portion 26 provided on the side surface of the connector housing 24 to shine. Can do. As a result, it can be detected that visible light is being sent to the optical fiber core wire 21. Therefore, by using the optical connector 20 of FIG. 2 for the optical connectors of the optical connecting members 8 and 9 of FIG. 1, it is possible to perform the contrast control without removing one of the optical connectors.

  The slit 27 for leaking visible light into the optical connector has a shape as shown in FIGS. 3 (A) and 3 (B), for example. The slit 27 is inserted into the fiber hole of the ferrule 22 with the glass fiber 21a from which the optical fiber coating has been removed and bonded and integrated. Then, the slit 27 crosses the axis of the ferrule 22 with a predetermined angle using a diamond cutter or the like. The glass fiber 21a is cut and cut to form the glass fiber 21a. This angle is preferably large so that visible light or communication light that has passed through the optical fiber does not return into the optical fiber, but communication light passes through the slit 27 as the angle θ increases. Loss increases. Therefore, it is desirable that the angle θ of the slit 27 is 2 ° or more, preferably 4 ° to 10 °.

  If the width W of the slit 27 is too small, the leakage of visible light is small and the visibility is lowered. If the width W is too large, the loss of signal light increases. For this reason, it is desirable that the thickness is 10 μm to 40 μm, and more preferably 20 μm to 30 μm. If it is 10 μm or less, it is difficult to process with a cutter blade, and if it is 40 μm or more, the loss of signal light is large and it is difficult to clear the specified value. The slit 27 may be left as a gap, but may be filled with a transparent resin material. Thereby, the loss with respect to a signal beam | light can be reduced more, and the fall of mechanical strength can be reduced more.

The slit angle θ and the slit width W may be appropriately set so that visible light can be sufficiently leaked to the outside while preventing loss of signal light from increasing. For example, if [theta] is 5 [deg.] To 7 [deg.] And W is 15 [mu] m to 25 [mu] m, the leaked visible light can be sufficiently visually recognized while the loss of the signal light is about 0.1 dB to 0.18.
In the above example, the slit 27 is formed so as to completely divide the glass fiber, but the core part in the glass fiber only needs to be divided, and a state in which a part of the glass fiber is left without being divided. It may be. Thereby, the possibility that the positional relationship between the glass fibers existing on both sides of the slit changes with time is also reduced.

  In order to effectively emit visible light to the outside, it is desirable that the ferrule 22 be formed of a material that scatters and transmits visible light leaked from the slit 27. Therefore, as the material of the ferrule 22, glass, ceramic, plastic, etc. having translucency and light scattering properties can be used. In particular, from the viewpoint of manufacturing accuracy, cost, etc., crystallized glass may be used. Good.

  By forming the slit as described above in the glass fiber in the ferrule of the optical connector, visible light can leak out of the optical fiber and be emitted. On the other hand, with respect to the signal light passing through the optical fiber together with the visible light, the loss due to the slit is suppressed to a predetermined value or less. Further, even if visible light for sending the optical fiber is sent to the optical fiber core in communication with the optical connector connected, communication can be performed without any trouble in optical communication. . Then, by confirming the visible light transmitted into the optical fiber visually from the side surface of the optical connector or the like, it is possible to easily perform the contrast control.

  FIG. 4 is a diagram illustrating an optical connection member that connects optical connectors to each other via a connection adapter. In the figure, 30 is a connection adapter, 31 is a glass fiber, 32 is an adapter ferrule, 33 is a connection sleeve, 34 is an adapter housing, 35a and 35b are receptacle portions, 36 is an adapter window portion, and 37 is a slit. Description of other reference numerals is omitted by using the same reference numerals as those used in FIG.

  In the example of FIG. 4, the light guide mechanism formed in the optical connector 20 described in FIG. 2 is provided on the connection adapter 30 side. The connection adapter 30 has receptacle portions 35a and 35b into which optical connectors are inserted at both ends, an adapter ferrule 32 is held and fixed at the center portion, and connection sleeves 33 are arranged on both sides thereof. The adapter ferrule 32 has a glass fiber 31 therein, and a slit 37 is provided in the adapter ferrule 32 in order to leak visible light transmitted into the optical fiber to the outside. The adapter housing 34 is formed with a window 36 capable of transmitting light in the vicinity of the slit 37. Since the connection adapter 30 is usually provided with a flange (not shown) for attachment to a support panel or the like at the center of the adapter housing 34, the window hole 36 is formed on a side surface not having this flange. Form.

  The slit 37 is formed in the adapter ferrule 32 in the same manner as described for the optical connector ferrule in FIG. The optical connector 20 is inserted into the receptacle portions 35a and 35b of the connection adapter 30, and the end faces of the ferrule 22 and the adapter ferrule 32 of the optical connector 20 are abutted to form an optical connection. In this case, the optical connector 20 can be a normal optical connector that does not have a light derivation mechanism.

  By configuring the connection adapter of the optical connection member as described above, the visible light transmitted from the optical fiber core wire 21 into the optical connector 20 is leaked by the slit 37 formed in the glass fiber 31 in the adapter ferrule 32. Thus, the light can be emitted to the outside through the window portion 36 of the adapter housing. Visible light emitted through the window portion 36 is emitted from the window portion 36 provided on the side surface of the adapter housing 34 and can be easily visually confirmed from the outside. As a result, it can be detected that visible light is being sent to the optical fiber core wire 21. Therefore, by using the connection adapter 30 of FIG. 3 as the optical connection members of the optical connection members 8 and 9 of FIG. 1, it is possible to perform the core line contrast without removing the optical connector.

  As described above, according to the optical connecting member according to the present invention, a part of visible light transmitted into the optical fiber core can be emitted to the outside of the optical connecting member, so that the visual contrast of the optical core can be easily performed. Can be done. Moreover, the optical fiber connecting member can be controlled in a state where the optical connector is disconnected from the optical wiring network, but can also be performed in a connected state. And this core line contrast by visible light does not have an influence on the communication by the signal light from which a wavelength differs, and can be implemented safely during communication.

  In addition, in the optical connection member according to the present invention, there is visible light transmitted through the slit in the optical fiber in addition to the leaked light leaking in the optical connection member. For this reason, even when a plurality of optical connecting members are used in multiple stages on the path of one optical fiber core wire, the amount of leaked light detected is reduced and the light intensity is weakened. The cord contrast can be performed also in other optical connecting members connected to the downstream side. In addition, when connecting optical connectors with each other via a connection adapter, the optical fiber connectors on both sides of the connection adapter can be used for optical fiber contrast, especially when optical connectors are arranged on both sides of the partition wall. become. In addition, even when optical connectors are directly connected without using a connection adapter, it is possible to perform cord contrast.

As described above, an example in which visible light is transmitted from the transmission device side (control device) has been described as an embodiment of the present invention. However, in laying construction of an optical cable or the like, visible light is transmitted from the subscriber terminal side and transmitted from the subscriber terminal. The present invention is also effective when performing optical fiber contrast between optical cable terminations.
In the embodiment of the present invention, an example in which a window portion is provided in a connector housing or an adapter housing and visible light is visually recognized from the outside of the housing has been shown. However, a housing formed of a transparent material instead of the window portion is shown. The same effect can be obtained by using the body.
Furthermore, in the embodiment of the present invention, an example in which the visible light derived from the optical connecting member is visually confirmed has been shown. However, when the visible light intensity is low and it is difficult to visually recognize, it is possible to use an optical sensor together. It is.

It is a figure explaining an example of the core line contrast system concerning the present invention. It is a figure explaining the example which provides the optical derivation | leading-out mechanism in an optical connector with the optical connection member by this invention. It is a figure explaining the slit which leaks visible light with the optical connection member by this invention. It is a figure explaining the example which provides a light derivation | leading-out mechanism in a connection adapter with the optical connection member by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Optical transmission apparatus, 2 ... Star coupler frame, 3 ... Optical cable termination frame, 4 (4a-4d) ... Optical cable (optical fiber core wire), 5 (5a-5d) ... Subscriber terminal, 6 (6a-6d) ) ... Optical fiber (branching optical fiber), 7a-7d ... Jumper wire, 8, 9 ... Optical connection member (optical connector, connection adapter), 10a, 10b ... Optical distribution board, 11 (11a-11d) ... Optical branching module (Optical coupler), 12, 13 ... Branch optical fiber, 14 ... Optical switch, 15 ... Control device, 16 ... Visible light source, 17 ... Optical pulse tester, 18 ... Light source for loss test, 20 ... Optical connector, 21 ... Optical fiber core wire (optical fiber cord), 21a ... glass fiber, 22 ... ferrule, 23 ... ferrule presser, 24 ... connector housing, 24a ... latch lever, 25 ... spring, 26 ... window, 27 Slit, 28 ... Boot, 30 ... connection adapter, 31 ... glass fiber, 32 ... adapter ferrule, 33 ... connecting sleeve, 34 ... adapter housing, 35a, 35b ... receptacle 36 ... adapter window, 37 ... slit.

Claims (3)

An optical connection member for detachably connecting optical fibers used for optical signal transmission, and in a state where the optical fiber is attached to the ferrule, the width W for leaking visible light to the optical fiber is 10 μm to 40 μm, A slit having an angle θ intersecting with the ferrule axis of 4 ° to 10 ° is provided, and a light derivation mechanism for emitting part of visible light input into the optical fiber to the outside is provided. Optical connecting member. The optical connection member according to claim 1, wherein the optical derivation mechanism is provided in an optical connector. The optical connection member according to claim 1, wherein the optical connection member includes the optical connection adapter that connects the optical connectors.

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