JPH1123923A - Optical fiber cable with external damage detecting function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To predict a decrease in the performance of the optical fiber cable in advance by increasing the precision of finding an abnormal place of the optical fiber cable and knowing the abnormality of the optical fiber cable. SOLUTION: The optical fiber cable 10a is formed by coating coated optical fibers 12 with an external layer 14 made of an insulating material. In this case, the inside space part of the external layer 14 or the inside space part of an external layer covering the coated optical fibers 12 is filled with a liquid body 16 containing a light accumulating type after-image fluorescent material and abnormality of the optical fiber cable 10a is known through the fluorescence action of the liquid body 16 flowing out of a damage position 14a of the external layer 14 to predict its decrease in performance in advance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber cable having a trauma detection function.

[0002]

2. Description of the Related Art In an optical fiber cable, which is a transmission medium of a communication signal in a communication system, quality control after the installation is sufficiently performed, and an abnormal point occurring after the installation of the optical fiber cable is detected at an early stage, and the optical transmission performance is improved. It is necessary to prevent the occurrence of disconnection and disconnection beforehand.

[0003] Quality control of an optical fiber cable after installation is performed by measuring optical transmission performance using an optical power meter, performing an optical pulse test, visually inspecting the appearance of the optical fiber cable, and the like.

[0004]

By the way, the former measurement and test are effective means for directly knowing the optical transmission performance of an optical fiber cable. It is not a means that can predict in advance the deterioration of the performance of the optical fiber cable.

[0005] In addition, the latter visual inspection is effective as a means for knowing abnormalities such as damage to the external appearance of the optical fiber cable and predicting in advance the sudden deterioration of the performance of the optical fiber cable. Is carried out by regular patrol work and patrol work immediately after the occurrence of disasters such as floods, typhoons, and lightning strikes. For this reason, in the conventional visual inspection, there is a problem that the number of man-hours is large, the abnormal part is easily overlooked, and the accuracy of finding the abnormal part is poor.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for detecting an abnormal point with a high accuracy, and
An object of the present invention is to make it possible to predict in advance the performance degradation of an optical fiber cable.

[0007]

According to the present invention, there is provided an optical fiber cable comprising a plurality of optical fiber cores covered with an outer layer made of an insulating material, and covering the inner space of the outer layer or the optical fiber core. A stream containing a phosphorescent afterglow phosphor material is sealed in an inner space portion of the outer layer.

In the optical fiber cable according to the present invention, the afterglow phosphor material is a powdery phosphorescent pigment,
The fluid body is preferably formed by uniformly dispersing the luminous pigment in oil.

The afterglow phosphor material used in the optical fiber cable according to the present invention is a long afterglow phosphor material containing a plurality of rare earth elements as main components, and is a powder having high luminance and long lasting phosphorescent pigment. Those commercially available in a form are preferred.

[0010]

In the optical fiber cable according to the present invention, when the outer layer is damaged to reach the inner space, a stream containing the afterglow phosphor material is spread from the inside of the optical fiber cable to the damaged portion. To the outside through The fluid discharged to the outside accumulates light by light irradiation and emits high-luminance fluorescent light for a long time.

For this reason, in the case of an optical fiber cable which is imagined outdoors,
It accumulates light by irradiating sunlight and emits fluorescent light with high brightness for a long time. It can be visually observed without approaching the optical fiber cable by night patrol work, and the damaged part of the outer layer of the optical fiber cable can be detected accurately and easily. .
Therefore, the accuracy of finding an abnormal part in the imaginary optical fiber cable is high, and it is possible to know in advance the abnormality of the optical fiber cable and to predict in advance the performance degradation of the optical fiber cable.

[0012] In an optical fiber cable laid underground, under the sea, or the like, a stream flowing out to the outside accumulates light by human light irradiation and emits fluorescence with high luminance for a long time. Therefore, light irradiation and fluorescence detection can be easily performed by an automatic inspection robot for optical fiber cables, and thereby, a damaged portion on the outer layer of the optical fiber cable can be accurately and easily detected. Therefore,
The accuracy of detecting an abnormal point in an optical fiber cable laid underground, under the sea, or the like is high, and it is possible to know in advance the abnormality of the optical fiber cable and to predict in advance the performance degradation of the optical fiber cable.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 shows a state in which a plurality of optical fiber cables are connected to each other via a connecting device and laid. The respective optical fiber cables 10a are connected to each other via the respective connection devices 10b, and constitute a communication system.

As shown in FIG. 2, the optical fiber cable 10a is composed of a tension member 11 made of steel wire, a plurality of optical fiber units 12 which are optical fiber cores, a support member 13, and a sheath 14 which is an outer layer. Each of the optical fiber units 12 has a fitting groove 1 of a support member 13 through which the tension member 11 is inserted.
3a, the sheath 1 is supported.
4.

The optical fiber cable 10a having such a structure
Is known, and the sheath 14 is formed of an organic insulating material such as polyethylene, and a gap 15 exists inside the sheath 14. This gap 15 is
And a flow body 16 containing a luminous pigment, which is an afterglow phosphor material, is sealed in the gap 15.

The fluid 16 is formed by adding 10% by weight of a powdery luminous pigment to lubricating oil and uniformly dispersing it. Each of the optical fiber units 12 in this state is applied to the outer periphery and is covered with the sheath 14 so as to be sealed inside the sheath 14.

The phosphorescent pigment is composed of a high-brightness, long-afterglow phosphor material containing several kinds of rare earths as main components. Commercially available products are Chemicolor NL (trade name, manufactured by Nippon Chemics Co., Ltd.) and Ultra Glow. (Trade name, manufactured by Nichia Chemical Industry Co., Ltd.) and Picarico (trade name, manufactured by Chemitech Co., Ltd.). In the optical fiber cable 10a, Chemicolor NL is used as a luminous pigment.

The optical fiber cable 10a having such a configuration
In the case where a damaged portion 14a reaching the inner space of the sheath 14 is formed, the fluid 1 containing the luminous pigment
6 is a sheath 14 from the inside of the optical fiber cable 10a.
Out to the outside through the damaged part 14a. The fluid 16 that has flowed out emits light by irradiating light, and emits light yellow-green fluorescence with high luminance for a long time.

For this reason, when the optical fiber cable 10a is aerial outdoors, the fluid 16 flowing out of the sheath 14 accumulates light by irradiating sunlight and emits fluorescence with high luminance for a long time. This fluorescence can be visually recognized without approaching the optical fiber cable 10a by night patrol, and the damaged portion 14a of the sheath 14 of the optical fiber cable 10a can be detected accurately and easily. Therefore, the accuracy of finding the damaged portion 14a of the imaginary optical fiber cable 10a is high, and it is possible to know the abnormality of the optical fiber cable 14 and to predict in advance the performance degradation of the optical fiber cable 10a.

When the optical fiber cable 10a is laid underground, underwater, or the like, the fluid 16 flowing out of the sheath 14 accumulates light due to human light irradiation and has high luminance for a long time. It fluoresces. For this reason, it is possible to easily detect the fluorescence of the fluid body 16 by irradiating light with the automatic inspection robot for the optical fiber cable 10a, thereby accurately and easily detecting the damaged portion 14a of the sheath 14 of the optical fiber cable 10a. Can be detected. Therefore, the accuracy of finding abnormal points in optical fiber cables laid underground, underwater, etc. is good,
It is possible to predict in advance the performance degradation of an optical fiber cable laid underground, underwater, or the like.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a communication system equipped with an optical fiber cable according to the present invention.

FIG. 2 is a sectional view of an optical fiber cable used in the communication system.

[Explanation of symbols]

10a: Optical fiber cable, 10b: Connection device, 1
DESCRIPTION OF SYMBOLS 1 ... Tension member, 12 ... Optical fiber unit, 1
3. Support member, 13a Fitting groove, 14 Sheath, 14a
... damage site, 15 ... gap, 16 ... fluid body.

Claims (2)

[Claims] An optical fiber cable comprising a plurality of optical fiber cores covered with an outer layer made of an insulating material, wherein light is stored in an inner space of the outer layer or an inner space of an outer layer covering the optical fiber core. An optical fiber cable with a damage detection function, characterized by enclosing a fluid containing a type of afterglow phosphor material. 2. The optical fiber cable according to claim 1, wherein the afterglow phosphor material is a powdery phosphorescent pigment, and the fluid body is formed by uniformly dispersing the phosphorescent pigment in oil. An optical fiber cable, characterized in that: