JP2004354245A - Method and device for confirming liveness of optical fiber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and device for confirming liveness of an optical fiber capable of visually confirming liveness of an optical fiber at always without cutting it. <P>SOLUTION: The method and the device comprise a process for slightly bending an optical fiber into waves while kept almost straight, a process for making the optical fiber transmit light, a process for always detecting the light leaked from the core of optical fiber which is caused by bending, and a process for confirming liveness of the optical fiber based on the light detected in the full-time detection process. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method and an apparatus capable of always managing the live state of an optical fiber by visual observation without cutting the optical fiber.
[0002]
[Prior art]
Conventionally, a method of checking the live state of an optical fiber has been to cut the optical fiber once in the middle, place a coupler at the cut portion, and check the light output from one end of the coupler with a power meter or the like.
[0003]
However, according to the conventional method, the work of cutting the optical fiber is required every time the state of the live line is checked, so that the state of the live line cannot be always checked. In addition, when a 10: 1 coupler is used, a large loss of 1/10 occurs, which is not suitable for confirming a live state.
[0004]
[Problems to be solved by the invention]
Therefore, an object of the present invention is to provide a live state check method of an optical fiber and a live state check apparatus of an optical fiber, which can always visually check the live state of the optical fiber without cutting the optical fiber. It is in.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, a method for confirming a live state of an optical fiber according to a first aspect of the present invention includes a step of bending and deforming an optical fiber in a slightly wavy shape while maintaining a substantially straight line. A step of transmitting light, a step of constantly detecting light leaking from the optical fiber core wire due to the bending deformation, and confirming a live state of the optical fiber based on the light detected in the constantly detecting step. And a step.
[0006]
According to the first aspect of the present invention, a live state of an optical fiber can be confirmed by detecting leaked light while minimizing transmission loss due to bending deformation. Further, according to the method of the present invention, it is not necessary to cut the optical fiber, so that the live state of the optical fiber can be easily confirmed.
[0007]
Further, in the method for confirming a live state of an optical fiber according to a second aspect of the present invention, in the first aspect, the step of confirming a live state of the optical fiber may include: after converting the leaked light into an electric signal. This is performed by displaying the information on a display that is visible to the operator. According to this aspect, the worker can always check the live state of the optical fiber only by monitoring the display, and the worker should take it to check the live state of the optical fiber. Work volume is drastically reduced.
[0008]
In addition, a live line state checking device for an optical fiber according to a third aspect of the present invention includes a clamp device that clamps the optical fiber in a state where the optical fiber bends slightly in a wave shape while maintaining a substantially straight line; A light detection unit that constantly detects light leaked from a slightly bent and deformed portion and converts the light into an electric signal, and a display unit that visually recognizes the presence of the leaked light based on the electric signal. It is characterized by having. According to this aspect, it is possible to check the live state of the optical fiber by detecting the leaked light while minimizing the transmission loss due to the bending deformation. Further, in the apparatus of the present invention, since it is not necessary to cut the optical fiber, it is possible to suppress the return loss and the like of the optical fiber characteristics.
[0009]
Further, according to a fourth aspect of the present invention, in the above-mentioned third aspect, the live state checking device for an optical fiber has a substantially rectangular parallelepiped shape. , The display unit is provided, the clamp device is provided on the back surface of the rectangular parallelepiped, and the output unit is provided on the side surface of the rectangular parallelepiped. According to this aspect, it is possible to provide an apparatus that is compact as a whole and excellent in storage and installation.
[0010]
Further, in the apparatus for confirming a live state of an optical fiber according to a fifth aspect of the present invention, in the above-mentioned third or fourth aspect, the clamp device may be configured to adjust an optical power loss amount in the optical fiber. And an adjusting means for adjusting the amount of clamping. According to this aspect, transmission loss can be suppressed as much as possible.
[0011]
Also, in the apparatus for checking the live state of an optical fiber according to a sixth aspect of the present invention, in any one of the third to fifth aspects, the light detection unit may be a first circuit unit connected to a light receiving sensor. And a second circuit unit having the same circuit as the first circuit unit and being grounded, wherein the display unit includes a switch selectively connectable to the first circuit unit and the second circuit unit. And the correction of the reference offset value accompanying a temperature change or the like is enabled by using the signal passed through the second circuit section as a reference offset value by switching the switch.
[0012]
Conventionally, when minute light is photoelectrically converted, an offset value due to a temperature change or the like must be artificially corrected using an offset knob or the like. According to this aspect, the first circuit unit and the second circuit unit have the same circuit configuration, the signal in the grounded second circuit unit is used as the reference offset value, and the first circuit unit and the second circuit unit are alternately switched. This makes it possible to easily correct the reference offset value accompanying a temperature change or the like without providing an offset knob or the like.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 (a), 1 (b) and 1 (c) are a partially broken plan view, a front view and a side view, respectively, showing an optical fiber live state checking apparatus 1 according to the present invention.
[0014]
The apparatus 1 for checking the live state of an optical fiber is mainly composed of a case body 3 having a rectangular parallelepiped shape as a whole, and a display section 4 is provided on the front side (the side shown in FIG. 1B). The display unit 4 is provided with two LEDs 5 and 7. One LED 5 emits green light when leaked light described below is detected, and the other LED 7 emits red light when no leaked light is detected. The color of the LED to be identified according to the state of the leakage light can be freely selected, and a display unit other than the LED, for example, a character display by a liquid crystal or a display that lights one of symbols such as “O” or “X” is displayed. A method or the like can be applied.
[0015]
A clamp device 11 for clamping the optical fiber 9 is provided on the rear surface of the case body 3 (upper side of FIG. 1A). As shown in FIG. 2, the clamp device 11 includes a movable clip 13 and a fixed clip 15 provided to face the movable clip 13. Two guide rods 17 are formed in the movable clip 13, and the distal ends of these guide rods 17 slidably pass through guide holes (not shown) formed in the fixed clip 15. A flange-shaped locking portion 19 is formed at the tip of the guide rod 17, and a compression coil spring 21 is provided between each locking portion 19 and the fixing clip 15. By the action of these compression coil springs 21, the movable clip 13 is always urged to move to the fixed clip 15 side.
[0016]
As shown in FIG. 2, the clip surface 23 of the movable clip 13 is formed into a corrugated uneven surface, and the clip surface 25 of the fixed clip 15 has a shape opposite to that of the clip surface 23 of the movable clip 13. Is formed on the uneven surface. The clip surface 25 of the fixing clip 15 provides a surface having a cushion material for preventing disturbance light. Thereby, when the clip surface 23 of the movable clip 13 and the clip surface 25 of the fixed clip 15 approach, both surfaces are aligned with almost no gap.
[0017]
The concave and convex shapes of the clip surface 23 of the movable clip 13 and the clip surface 25 of the fixed clip 15 are such that when the optical fiber core wire 9 is sandwiched therebetween, the optical fiber core wire 9 that is curved and deformed along the concave and convex surface is substantially straight. , While being slightly deformed in a wavy manner. Here, "slightly bend and deform" means that the light leaks from the bent and deformed portion of the optical fiber core wire 9 as little as possible and the degree of deformation is such that the optical transmission function as an optical communication line can be maintained. Say.
[0018]
As shown in FIG. 2, a screw hole 27 is formed at the center of the movable clip 13 of the clamp device 11 and opens to the fixed clip 15 side. An adjusting screw 29 serving as an adjusting means is screwed into the screw hole 27. ing. The tip of the adjusting screw 29 abuts on the clip surface 25 of the fixing clip 15, so that the distance between the two clip surfaces can be defined. The degree of protrusion of the adjusting screw 29 from the screw hole 27 can be adjusted by rotating the adjusting screw 29, whereby the distance between the two clip surfaces can be changed, and therefore the amount of light loss of the optical fiber core wire 9 can be adjusted. Can be changed.
[0019]
If the protrusion of the tip of the adjusting screw 29 is adjusted to be longer, the distance between the two clip surfaces is increased, the degree of bending deformation of the optical fiber core wire 9 is reduced, and the amount of light leaking from the bent portion is reduced. . On the other hand, if the protrusion of the tip of the adjusting screw 29 is adjusted to be shorter, the distance between the two clip surfaces is reduced, the degree of bending deformation of the optical fiber core wire 9 is increased, and the amount of light leaking from the bent portion Increases. Thus, the adjusting screw 29 can be appropriately adjusted so that the optical transmission function of the optical fiber core wire 9 is not impaired and the amount of light leakage necessary for determining the live state described later is obtained.
[0020]
As shown in FIG. 1C, an output unit 31 is formed on a side surface of the case main body 3, and external remote control is possible via the output unit 31. Further, an electronic circuit section 33 as shown in FIG. 3 is provided inside the case body 3.
[0021]
The electronic circuit unit 33 includes a light detection unit 34, and the light detection unit 34 includes a first circuit unit 35a and a second circuit unit 35b configured of two identical circuits. The first circuit section 35a is connected to the light receiving sensor 37, and the second circuit section 35b is grounded. An amplifier 39 is selectively connected to the first circuit unit 35a and the second circuit unit 35b via a switch 41, and the display unit 4 is connected to the amplifier 39 via a CPU 43. By switching the switch 41, the signal in the grounded second circuit unit 35b is used as a reference offset value, and the value of the signal in the first circuit unit 35a is compared with the reference offset value to determine the presence of light leaking. Can be detected. The detected electric signal of the leaked light is amplified by the first circuit unit 35a and the amplifier 39, and based on this signal, the CPU 43 issues a command to cause the green LED 5 to emit light. When the electric signal of the leakage light is not detected, the CPU 43 issues a command to make the red LED 7 emit light.
[0022]
Next, the operation of the present invention according to the present embodiment will be described. First, as shown in FIG. 2, the movable clip 13 is separated from the fixed clip 15 against the urging force of the compression coil spring 21, and the optical fiber core wire 9 is moved between the clip surface 23 of the movable clip and the clip surface 25 of the fixed clip. To place. Then, when the movable clip 13 is released, the optical fiber core wire 9 is held between the clip surface 23 of the movable clip and the clip surface 25 of the fixed clip by the urging force of the compression coil spring 21. Since both clip surfaces 23 and 25 are bent in a wave shape, the optical fiber core wire 9 is slightly bent in a wave shape while maintaining a substantially straight line.
[0023]
When light is transmitted to the optical fiber core 9 in this state, a part of the light leaks from the slightly bent and deformed portion of the optical fiber core 9, and the light receiving sensor 37 detects this. At this time, since the optical fiber 9 is only slightly deformed, the transmission loss of light passing through the optical fiber 9 is minimized. When the leak light is detected by the light receiving sensor 37, the green LED 5 is illuminated on the display unit 4, and the worker can visually check the green LED 5 to check the live state of the optical fiber. On the other hand, if no leakage light from the optical fiber core 9 is detected, the CPU 43 determines this and the red LED 7 is turned on. Can be confirmed that there is no. As described above, according to the present invention, the worker can always visually confirm the live state of the optical fiber by monitoring the display unit 4.
[Brief description of the drawings]
FIG. 1A is a partially cutaway plan view showing an apparatus for checking a live state of an optical fiber according to the present invention, FIG. 1B is a front view thereof, and FIG. 1C is a side view thereof.
FIG. 2 is a plan view showing a clamp unit and a display unit of the apparatus for checking the live state of an optical fiber.
FIG. 3 is a circuit diagram showing a configuration of an electronic circuit unit of the apparatus for checking a live state of an optical fiber.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Optical fiber live state check device 3 Case main body 4 Display unit 5 LED
7 LED
9 Optical fiber core wire 11 Clamp device 13 Movable clip 15 Fixed clip 17 Guide rod 19 Locking portion 21 Compression coil spring 23 Clip surface 25 of movable clip Clip surface 27 of fixed clip 27 Screw hole 29 Adjusting screw 31 Output unit 33 Electronic circuit unit 34 Light detection unit 35a First circuit unit 35b Second circuit unit 37 Light receiving sensor 39 Amplifier 41 Switch 43 CPU

Claims (6)

A step of bending the optical fiber in a slightly wavy shape while maintaining a substantially straight line;
Transmitting light to the optical fiber,
A step of constantly detecting light leaked from the optical fiber core wire due to the bending deformation,
Checking the live state of the optical fiber based on the light detected in the continuous detection step. 2. The optical fiber activation method according to claim 1, wherein the live state check step of the optical fiber is performed by converting the leaked light into an electric signal and displaying the electric signal on a display which can be viewed by an operator. Line condition confirmation method. A clamping device that clamps in a state where the optical fiber is bent slightly in a wave shape while maintaining a substantially straight line,
A light detector that constantly detects light leaking from the slightly bent and deformed portion of the optical fiber, and converts the light into an electric signal;
A live-line state confirming device for an optical fiber, comprising: a display unit for visually recognizing the presence of the leakage light based on the electric signal. In claim 3, the live-line state checking device of the optical fiber has a substantially rectangular parallelepiped shape, the display unit is provided on the front surface of the rectangular parallelepiped shape, and the clamp device is provided on the rear surface of the rectangular parallelepiped shape, An apparatus for checking the live state of an optical fiber, comprising an output unit on a side surface. 5. The apparatus according to claim 3, wherein the clamp device includes an adjusting unit that adjusts a clamp amount to adjust the amount of light leakage. 6. The light detection unit according to any one of claims 3 to 5, wherein the light detection unit includes a first circuit unit connected to a light receiving sensor, and a second circuit unit that includes the same circuit as the first circuit unit and is grounded. The display unit is connected to the first circuit unit and the second circuit unit via a switch that can be selectively connected, and by switching the switch, the signal via the second circuit unit is offset by a reference offset. An apparatus for confirming a live state of an optical fiber, wherein a reference offset value accompanying a temperature change or the like can be corrected as a value.

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