JPH11109132A - Discriminating device for optical path, and discriminating method of optical path using the device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a discriminating device of optical path capable of discriminating light having at least two wavelengths while minimizing the influence of bending on an optical path, and a discriminating method of optical path using this device. SOLUTION: This device is provided with a bending imparting member 10 for imparting a prescribed bending to an optical line 8, a core wire fixing member 12 for fixing the optical line 8 having the prescribed bending imparted by the bending imparting member 10, and a light receiving element 14 for receiving the light leaked from the optical line 8 to which the prescribed bending imparted by the bending imparting member 10. The bending imparting member 10 has a means for imparting a bending with at least two different curvature radiuses, or a first curvature radius and a second curvature radius larger than the first curvature radius.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical line identification apparatus for identifying an optical fiber core in an optical line and an optical line identification method using the same. More specifically, the present invention relates to an optical line identification device for identifying at least two types of light without cutting an optical fiber core in an optical line in a live state, and an optical line identification method using the same.

[0002]

2. Description of the Related Art Due to a change in the route of an optical line composed of optical fiber cores currently used for optical communication and an increase in the number of optical networks, some of the optical fiber cores of the working optical line are replaced with optical fibers of other optical lines. It may be switched to the core wire and connected. In this case, the operator visually checks the position of each optical fiber core in the optical line, or traces the color of the optical fiber to identify and connect the optical fiber core in the optical line. Determine the core wire. By the way, it is not possible to sufficiently satisfy the reliability and the work efficiency by the above-mentioned visual identification of the core wire depending on the skill of the worker, and particularly in the case of the active optical line in the live state, the efficiency of the optical line construction is improved. Therefore, there is a strong demand for labor saving and reduction of operation errors.

In order to meet this demand, a state in which light is transmitted to an optical fiber in an optical line, the optical fiber is bent at a predetermined curvature, and a part of the light leaks from the bent portion. There has been proposed a method of detecting the target optical fiber and detecting the target optical fiber. Since this method can identify the target optical fiber core without cutting the optical fiber core in the optical line, the reliability of the core identification can be improved and the communication is cut off at the time of the core identification. There is an advantage that switching can be performed without any change, and the work time for connection can be reduced.

[0004]

In recent years, with the development of optical communication networks, optical transmission systems have been proposed which individually transmit light having different wavelengths to optical fiber cores in the same optical line. For example, when four out of ten optical fiber cores are light having a wavelength in the 1.55 μm band, four are light having a wavelength in the 1.3 μm band, and the remaining two are spare optical fiber cores. The following problems were found in the identification of the cords. When the optical fiber is bent at a predetermined curvature and a part of the light is leaked from the bent portion in the identification of the optical fiber, for example, the optical fiber has a radius of about 7. When bent in mm, light in the 1.55 μm band can be detected up to −30 dBm, but light in the 1.3 μm band cannot be detected. Therefore, light having a wavelength of 1.3 μm band is -30 dB.
In order to be able to detect up to m, the optical fiber core must be bent with a radius of about 4.5 mm.

Therefore, when all the optical fiber core wires are bent at a radius of about 4.5 mm, the light in the 1.55 μm band has a large amount of leaked light, and for example, the light in the 1.55 μm band is the working light. In this case, there is a problem that communication is disconnected. In addition, bending the optical fiber core with a radius of about 4.5 mm means that the curvature of the optical fiber core is very large, so that the core coating may be damaged or the optical fiber core may be bent after identification. Therefore, it is not preferable that the curvature is increased because there is a possibility that residual strain may be applied.

The present invention solves the above problems, and uses an optical line discriminating apparatus and an optical line discriminating apparatus capable of discriminating at least two kinds of wavelengths of light with a minimum effect on the optical fiber core due to bending. It is an object of the present invention to provide a method for identifying an optical line.

[0007]

The present invention has the following means to solve the above problems.

According to a first aspect of the present invention, there is provided an optical line discriminating apparatus for providing a predetermined bending to an optical fiber core, and an optical fiber core provided with a predetermined bending by the bending applying member. An optical fiber line identification device comprising: a core fixing member for fixing the optical fiber at a predetermined position; and a light receiving element for receiving light leaked from the optical fiber core provided with a predetermined bending by the bending applying member. Wherein the bending member has means for bending the optical fiber with at least two different first curvatures and a second curvature larger than the first curvature. . Optical line identification device.

According to a second aspect of the present invention, there is provided a method for identifying an optical line, comprising: a bending member for applying a predetermined bend to an optical fiber core; and an optical fiber core having a predetermined bend applied by the bending member. And a light receiving element that receives light leaked from the optical fiber core that has been given a predetermined bend by the bending applying member, wherein the bending applying member has an optical fiber core. At least 2 on the line
First, using an optical line discriminating device having means for imparting a bend at a different first curvature and a second curvature greater than the first curvature, an optical fiber having a first curvature is first used. By giving a bend to the cord, the light leaking from the optical fiber cord is received by the light receiving element to identify the presence or absence of the leaked light, and it is determined that the leaked light is above a certain detection level. If it is determined that the light transmitted through the optical fiber core is light in the optical wavelength band leaking at the first curvature, if it is determined that the leaking light is below a certain detection level, the first Assuming that light in the optical wavelength band leaking at the curvature of the optical fiber core is not transmitted to the optical fiber core, the optical fiber core is bent at a second curvature larger than the first curvature to give the optical fiber core. The light receiving element receives the light leaked from the wire and has the leaked light. If it is determined that the leaking light is equal to or higher than a certain detection level, it is determined that the light transmitted through the optical fiber core is light in the optical wavelength band leaking at the second curvature. Further, when it is determined that the leaked light is below a certain detection level, it is determined that neither the light in the light wavelength band leaking at the first curvature nor the light in the light wavelength band leaking at the second curvature is present. Features.

According to the optical line discriminating apparatus and the optical line discriminating method using the same according to the present invention, the bending-applying member has at least two types of different first and second curvatures on the optical fiber. Since it has means for giving a bend with a second curvature that is also large, it is possible to efficiently identify at least two types of light in different light wavelength bands.

First, a light having a small curvature is given to the optical fiber, and the light leaked from the optical fiber is received by the light receiving element and leaked with less bending damage given to the optical fiber. Identify the presence or absence of light. If it is determined that the leaking light is at or above a certain detection level, the light transmitted through the optical fiber core is identified as the light in the light wavelength band that leaks at the first curvature, and bending is performed again. Absent.

That is, the light that is identified as the light in the optical wavelength band that leaks due to the initial bending with a small curvature will not be bent with a larger curvature.
It is possible to eliminate effects such as damage to the core coating that may be caused by bending and residual strain that may remain after the core identification. Of course, even if the light transmitted through the optical fiber is the working light, no further bending is performed, so that the communication is not interrupted.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to embodiments. FIG. 1 is a schematic diagram showing an embodiment of an optical line identification device and an optical line identification method using the same according to the present invention. In the figure, 2 is an electric / optical converter, 4 is an optical line, 5 is a device for identifying the optical line 4, and 6 is an optical / electric converter.

FIGS. 2A and 2B are schematic views showing a main part of the identification device of FIG. The optical line identification device 5 includes:
A bending member 10 for bending the optical fiber core 8 of the optical line 4; a core fixing member 12 for fixing the optical fiber core 8 bent by the bending member 10 at a predetermined position; Light receiving element 17 for receiving light leaked from optical fiber core 8 bent by applying member 10
The optical / electrical converter 14 is formed. In the figure, reference numeral 16 denotes a drive power supply for the optical / electrical converter 14.

An optical line identification method using the optical line identification device 5 of the present invention will be described below. In the optical line 4,
For example, an optical line 8 transmitting 1.55 μm band wavelength light
It is assumed that there are four optical lines 8 transmitting light in the 1.30 μm band wavelength and two optical lines 8 not transmitting light. The bending applying member 10 of the optical line discriminating apparatus 5 can set the amount of pushing to apply bending to the optical line 8 in two stages. The optical line 8 set in the identification device 5 is loosely grasped by the core fixing member 12, and
It is fixed at the position of the bending applying member 10 shown in FIG.

In the present embodiment, the position of the bending applying member 10 shown in FIG. 2A is the position of the first curvature and is the identification position of the low loss mode. In the present embodiment, for example, 1.5
It is a gentle bend that can detect light in the 5 μm band up to −30 dBm. In the present embodiment, the position of the bending imparting member 10 shown in FIG. 2B is a position of a second curvature larger than the first curvature, and is a discrimination position of the high loss mode. In the present embodiment, for example, the bending is a tight bend capable of detecting light in a 1.30 μm band wavelength to −30 dBm. The position of the first curvature of the bending member 10 shown in FIG. 2A and the position of the second curvature of the bending member 10 shown in FIG. 2B are set by the pushing amount of the bending member 10. I have. The set position of the pushing amount is a value experimentally obtained.

First, at the position of the first curvature of the bending applying member 10 shown in FIG. 2A, first, the leakage light of the light that may be transmitted through the optical line 8 is converted into the light / light from the light receiving element. The light is received by the electric converter 14. When the optical / electrical converter 14 receives the leaked light, it can be identified that the leaked light is light of a 1.55 μm band wavelength that leaks even with a gentle bending of a radius R = 6.8 ± 0.2 mm. . If the optical line 8 transmitting the light in the 1.55 μm band is bent at a greater curvature, the transmission loss increases. For example, if the light is working light, communication is cut off. However, since the optical line 8 does not bend at a higher curvature, the communication is not interrupted. If the optical / electrical converter 14 does not receive the leaked light,
Even in the case of gentle bending with a radius R of 6.8 ± 0.2 mm, light in the 1.55 μm band wavelength leaking is not transmitted, and light in the 1.30 μm band wavelength is transmitted to this optical line 8. Or an empty line.

Therefore, at the position of the second curvature of the bending applying member 10 shown in FIG. 2 (b), the leakage light of the light which may be transmitted through the optical line 8 is converted into a light / electrical conversion by a light receiving element. The light is received by the detector 14. When the optical / electrical converter 14 receives the leaked light, it can be identified that the leaked light is light in a 1.30 μm band wavelength leaking due to tight bending. If the optical line 8 transmitting the light in the 1.30 μm band is bent at a greater curvature, the transmission loss will increase. For example, if this light is working light, communication will be interrupted. However, since this optical line 8 does not bend at a higher curvature,
There is no disruption to communications. If the optical / electrical converter 14 does not receive the leaked light,
It can be seen that the light of the 1.30 μm band wavelength that leaks even in tight bending is not transmitted. Since the optical line 8 is not bent at a curvature larger than that, damage to the core coating that may be caused by the bending and residual strain that may remain even after the identification of the core is reduced. I will not give.

In the above embodiment, the light transmitted to the optical line 8 is described as the working light. However, the light does not need to be the working light, for example, 1.30 μm.
Of course, the optical line 8 can be identified by transmitting the test light of the band wavelength and the test light of the 1.55 μm band wavelength.

[0020]

As described above, according to the optical line identification device and the optical line identification method using the same according to the present invention,
Since the bending member has means for bending the optical fiber with at least two different first curvatures and a second curvature larger than the first curvature, at least two bends are provided.
Light in different types of light wavelength bands can be efficiently identified. First, a bend with a small curvature is given to the optical fiber core, and the presence or absence of light leaking from the optical fiber core with little bending damage to the optical fiber core is identified. The light that is identified as being in the optical wavelength band will not be bent with a larger curvature, so that damage to the core coating that may be caused by bending and that remains after the core is identified. It is possible to eliminate the influence of residual strain and the like that may occur. Of course, even if the light transmitted through the optical fiber is the working light, no further bending is performed, so that the communication is not interrupted.

Further, since the light that is identified as the light in the light wavelength band that leaks due to the bending of the second curvature larger than the first curvature is not bent with a curvature larger than this, Even if the light transmitted through the optical fiber core is working light, no further bending is performed, so that the communication is not interrupted.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an embodiment of an optical line identification device and an optical line identification method using the same according to the present invention.

FIGS. 2A and 2B are schematic diagrams showing a main part of the identification device of FIG. 1;

[Explanation of symbols]

 Reference Signs List 2 electric / optical converter 4 optical line 5 optical line discriminating device 6 optical / electric converter 8 optical line 10 bending member 12 core fixing member 14 optical / electric converter 16 drive power supply 17 light receiving element

Claims (2)

[Claims] A bending member for applying a predetermined bend to the optical fiber, a core fixing member for fixing the optical fiber having the predetermined bending by the bending member at a predetermined position, An optical line discriminating device including a light receiving element that receives light leaked from an optical fiber core that has been given a predetermined bending by the bending applying member, wherein the bending applying member has at least two optical fibers. An apparatus for identifying an optical line, comprising: means for imparting a bend with a different first curvature and a second curvature larger than the first curvature. 2. A bending member for applying a predetermined bend to an optical fiber core, a core fixing member for fixing an optical fiber core given a predetermined bend by the bending member to a predetermined position, The optical fiber core includes a light receiving element that receives light leaked from the optical fiber core to which a predetermined bending is applied by the bending applying member, wherein the bending applying member has at least two different first curvatures on the optical fiber core. Using an optical line discriminating device having means for imparting a bend at a second curvature greater than the first curvature, first imparting a bend to the optical fiber core wire at a first curvature, The light leaking from the optical fiber core is received by the light receiving element to identify the presence or absence of the leaked light, and when it is determined that the leaked light is equal to or higher than a certain detection level, the optical fiber core is replaced. The transmitted light leaks at the first curvature. The light in the wavelength band to be leaked is identified, and when it is determined that the light to be leaked is below a certain detection level, the light in the wavelength band to be leaked at the first curvature is transmitted to the optical fiber core. Assuming that there is no light leaking from the light receiving element by receiving light leaked from the optical fiber core by bending the optical fiber core with a second curvature larger than the first curvature. Identify and, if it is determined that the leaking light is above a certain detection level, the light transmitting the optical fiber core wire is identified as light in the optical wavelength band leaking at the second curvature, Further, when it is determined that the leaked light is below a certain detection level, it is distinguished that there is no light in the light wavelength band leaking at the first curvature and no light in the light wavelength band leaking at the second curvature. The method of identifying the optical line.