JP2009175612A - Optical connector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical connector, capable of easily performing optical fiber identification in each of a state where connection of the optical connector is released and an optical communication state without releasing connection of the optical connector. <P>SOLUTION: The optical connector 20 to be connected to an end of an optical fiber used for optical signal transmission includes a fiber connection part 27 having a short optical fiber 21b connected to the inside thereof, and a light guide mechanism 26 for leading a part of visible light by the fiber connection part 27 to the outside as leak light. The fiber connection part 27 may be provided within a ferrule 22, and in this case, the ferrule 22 is desirably formed of a material scattering-transmitting the leak light. As the material scattering-transmitting the leak light, for example, crystallized glass can be used. As the visible light, red light is preferably used. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optical connector used for connecting many optical fibers, such as an optical wiring board 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 fibers when newly laying 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. A method is disclosed in which visible light (or reference light) is incident and the optical fiber core wire is diffused and transmitted through an optical connector cap provided at a terminal on the terminal side of the optical fiber core wire to perform the core wire contrast. .

  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.

Patent Document 3 discloses a method for visually recognizing a predetermined optical communication cable by forming a notch or an opening in an adapter for connecting optical connectors to each other so that visible light leaking from the optical connector leaks to the outside. 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 a highly dense optical wiring facility in a station or the like. 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 that visible light leaking from an optical connector is disclosed, but details of the mechanism of occurrence of visible light leakage and the visibility thereof are not disclosed. However, visible light leakage is caused by slight axial misalignment between the optical fibers at the ferrule end portion of the optical connector that is abutted at an intermediate position of the connection adapter, and this leaked light is cut off at both end portions of the adapter. What is visually recognized through a notch or opening is assumed.

  However, 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 though 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, and therefore cannot be detected. In a state where the optical connector is not connected to the adapter, the housing of the optical connector The outer surface of the optical connector cannot be identified, and the ferrule end of the optical connector is looked into. Further, since the existing connection adapter provided in the optical wiring board cannot detect the leak light, there is a problem that it must be used in place of the connection adapter capable of detecting the leak 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 connector capable of satisfying the requirements.

  The optical connector according to the present invention is an optical connector used for optical fiber connection, and is provided with a fiber connection part in which a short optical fiber is connected inside, and a part of visible light generated by this fiber connection part is led to the outside as leakage light. A light derivation mechanism is provided. The fiber connection portion may be provided in the ferrule. In this case, the ferrule is preferably formed of a material that scatters and transmits leaked light. Moreover, when forming the said fiber connection part out of a ferrule, it is desirable that the member which protects a fiber connection part is formed with the material which scatters and permeate | transmits leaked light. For example, crystallized glass can be used as a material that scatters and transmits leaked light. Moreover, it is preferable to use red light for visible light.

  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. In addition, the optical connection members 8 and 9 used in the present invention refer to a connection form by “optical connector + optical connector” and a connection form by “optical connector + connection adapter + optical connector”.

  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 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 wire to the outside, and visible light emitted from the light deriving mechanism is provided. Contrast is performed by visual recognition.

  2 and 3 are diagrams for explaining the first embodiment according to the present invention, and FIG. 2 is a diagram for explaining the second embodiment. In the figure, 20 is an optical connector, 21 is an optical fiber core (optical fiber cord), 21a is a tip, 21b is a short optical fiber, 22 is a ferrule, 23 is a ferrule holder, 24 is a connector housing, 25 is a spring, Reference numeral 26 denotes a window portion, 27 denotes a fiber connection portion, 28 denotes a boot, 29 denotes a reinforcing sleeve, and 30 denotes a mechanical splicer.

  As shown in FIGS. 2 and 3, an optical connector 20 according to the present invention leaks visible light transmitted into an optical fiber core wire 21 (also referred to as an optical fiber cord) and scatters and transmits the visible light to the outside. 20 is provided with a fiber connecting portion 27. Since the optical connector 20 has the fiber connection portion 27, the fiber connection portion 27 can be provided by connecting the short optical fiber 21b to the distal end portion 21a of the optical fiber core wire 21. The fiber connection portion 27 can be formed by fusion splicing or mechanical butt connection.

  The leakage of visible light sent into the optical fiber core wire 21 can be caused by a slight axial shift at the connection between the optical fibers. Therefore, by providing the fiber connection portion 27 in the optical connector 20, a part of the visible light transmitted to the optical fiber core wire 21 together with the signal light can be leaked into the optical connector 20. Then, the visible light leaked into the optical connector 20 is scattered and transmitted, and leaked to the outside of the optical connector 20 through a light derivation mechanism such as a window portion 26 that reaches the outer surface of the optical connector, whereby an optical fiber core is obtained. The line 21 can be identified. 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.

  FIG. 2A shows an example of the optical connector 20 described above, and is an example in which the fiber connection portion 27 is provided in the ferrule 22. In this example, in the fiber insertion hole of the ferrule 22, a fiber connection portion 27 formed by fusing or butting the tip portion 21 a from which the coating of the optical fiber core wire 21 is removed and the short optical fiber 21 b is provided. . And the front-end | tip part 21a of the optical fiber core wire 21, the fiber connection part 27, and the short optical fiber 21b are hold | maintained and fixed to the ferrule 22 with an adhesive etc., and are integrated.

  Moreover, the window part 26 for releasing the leakage light leaked in the optical connector 20 outside is formed in the part in which the fiber connection part 27 is located, or its vicinity. 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. In order to effectively emit visible light to the outside, it is desirable that the ferrule 22 covering the fiber connection portion 27 is formed of a material that scatters and transmits the leaked visible light. Therefore, as the material of the ferrule 22, glass, ceramic, plastic, and the like having translucency and light scattering properties can be used. In particular, it is preferable to use crystallized glass from the viewpoint of manufacturing accuracy, cost, and the like.

  The structure of the other optical connector 20 is the same as a general optical connector structure. For example, the ferrule 22 is held by a ferrule holder 23 and is urged in the axial direction by a spring 25 or the like on the connector housing 24. Installed. 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.

  As shown in FIG. 2B, the visible light emitted to the outside through the window portion 26 is easily confirmed visually 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, the cords can be easily compared without removing the optical connector.

  FIG. 3 shows another example of the optical connector 20 described above, and is an example in which the fiber connecting portion 27 is provided on the rear outer side of the ferrule 22. 3A shows an example in which the fiber connection is formed by fusion splicing, and FIG. 3B shows an example in which the fiber connection is formed by a mechanical splice.

  In FIG. 3A, the rear end portion of the short optical fiber 21b held in the ferrule 22 protrudes from the rear end of the ferrule 22, and is connected to the front end portion 21a of the optical fiber core wire 21 by fusion connection. A portion 27 is formed. The fiber connection portion 27 formed by fusion splicing is usually reinforced by the reinforcing sleeve 29 because it is mechanically weak. The reinforcing sleeve 29 is reinforced by, for example, storing a reinforcing rod and a heat-melting sleeve (adhesive resin) in advance in a heat-shrinkable resin sleeve, and applying heat treatment to cover the fused portion of the optical fiber. The sleeve is melted and the heat-shrinkable resin sleeve is shrink-cured to protect and reinforce the fusion spliced portion.

  Since the reinforcing sleeve 29 is usually formed of a translucent sleeve, visible light can be leaked from the fiber connecting portion 27 by fusion. Similar to the case of FIG. 2, the window portion 26 for emitting the leaked light leaked into the optical connector reaches the outer surface of the optical connector at or near the portion where the fiber connection portion 27 is located. Formed as follows. In the case of FIG. 3A, since the position of the fiber connection portion 27 is closer to the boot 28, the window portion 26 penetrates the fiber casing 24 and the boot 28. In addition, this window part 26 can be formed in the form by which multiple small window holes were provided in the housing | casing surface of an optical connector similarly to the case of FIG.

  Further, in order to effectively emit visible light to the outside, the reinforcing sleeve 29 covering the fiber connecting portion 27 is formed of a material that scatters and transmits the leaked visible light. desirable. For example, as the material of the reinforcing sleeve 29, a plastic containing a filler that scatters visible light or the like can be used. Further, as the reinforcing sleeve 29, a glass tube or a ceramic tube can be used instead of the heat-shrinkable sleeve. In this case, an adhesive is used for the adhesion and fixing, and when a glass tube is used, crystallized glass can be used.

  In FIG. 3B, a mechanical splicer 30 is used to connect the short optical fiber 21b held in the ferrule 22 and the distal end portion 21a of the optical fiber core wire 21, and a fiber connection portion 27 is formed by a butt connection. . For example, the mechanical splicer 30 is integrally formed on the rear side of the ferrule retainer 23, and the rear end portion of the short optical fiber 21b protruding from the rear portion of the ferrule 22 and the front end portion 21a of the optical fiber core wire 21 are It is the structure which is fixed by connecting by aligning with a groove | channel and holding with a pair of clamp member.

  As in the case of FIG. 3A, the window portion 26 for emitting the leaked light leaked into the optical connector 20 to the outside is located at or near the portion where the fiber connection portion 27 is located. It is formed to reach the outer surface. However, when the mechanical splicer 30 is used, visible light may be blocked from the fiber connection portion 27 by the splicer clamp member. Therefore, it is desirable to use the mechanical splicer 30 made of a light-transmitting and mechanically strong material.

  Further, in order to effectively emit visible light to the outside, the mechanical splicer 30 scatters the leaked visible light in the same manner as described in FIGS. 2 (A) and 3 (A). -It is desirable that it is made of a material to be transmitted. Therefore, as the material of the mechanical splicer 30, a plastic material having translucency and light scattering properties is used, but glass and ceramic can also be used. Note that when glass is used, crystallized glass can be used.

  As described above, according to the optical connector 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 connector, and the visual core comparison is easily performed. be able to. Further, the optical fiber connector can be controlled in a state where the optical connector is disconnected from the connection of 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.

  The optical connector according to the present invention also has visible light that passes through the optical fiber in addition to the leaked light leaking in the optical connector. For this reason, even when a plurality of optical connectors are used in multiple stages on the path of one optical fiber core wire, the amount of the leaked light detected is reduced and the light intensity is weakened. The optical fiber line contrast can be performed also in other optical connectors connected to the downstream side. In addition, when optical connectors are connected via an adapter, the optical fiber connectors on both sides of the adapter can be contrasted, and particularly when the optical connectors are arranged on both sides of the partition wall, the optical fiber lines can be easily compared. . In addition, even when optical connectors are directly connected without using an adapter, it is possible to perform cord contrast.

As described above, the embodiment of the present invention has been described with an example in which visible light is transmitted from the transmission device side (control device). 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.
Further, in the embodiment of the present invention, an example in which a window portion is provided in the connector housing and visible light is visually recognized from the outside of the connector has been shown, but a connector housing formed of a transparent material is used instead of the window portion. Thus, the same effect can be obtained.
Furthermore, in the embodiment of the present invention, an example in which the visible light derived from the optical connector 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. is there.

It is a figure explaining an example of the core line contrast system concerning the present invention. It is a figure explaining 1st Embodiment of the optical connector by this invention. It is a figure explaining 2nd Embodiment of the optical connector 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 connecting member (optical connector), 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 ... tip, 21b ... short optical fiber, 22 ... ferrule, 23 ... ferrule holder, 24 ... connector housing, 24a ... latch lever, 25 ... spring, 26 ... window, 2 ... fiber connecting portion, 28 ... boots, 29 ... reinforcing sleeve, 30 ... mechanical splicer.

Claims (6)

  An optical connector used for optical fiber connection of an optical wiring network, provided with a fiber connection part in which a short optical fiber is connected inside, and part of visible light generated by the fiber connection part is led to the outside as leakage light An optical connector comprising a light derivation mechanism.   The optical connector according to claim 1, wherein the fiber connection portion is provided in a ferrule.   The optical connector according to claim 2, wherein the ferrule is formed of a material that scatters and transmits the leaked light.   The optical connector according to claim 1, wherein a member that protects the fiber connection portion is formed of a material that scatters and transmits the leaked light.   5. The optical connector according to claim 3, wherein the material that scatters and transmits the leaked light is crystallized glass.   The optical connector according to claim 1, wherein the visible light is red light.

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