JP4221252B2 - Core wire contrast method and apparatus - Google Patents

Description

  The present invention relates to a method and an apparatus for contrasting optical fibers, in which test light is incident on an optical fiber core, the test light is received at a control point, and the optical fiber core is contrasted.

  Since many optical fiber cables are composed of a plurality of optical fiber cores and are laid over a long distance, when these optical fiber core wires are cut or connected at the tip or in the middle, the optical fiber cores are used. It is necessary to carry out a cord contrast work in which the wires are contrasted one by one between one end of the optical fiber and the working point to confirm that they are the same optical fiber.

  In the control operation, the test light is incident from one end of the optical fiber to be controlled, the optical fiber is bent at the control point, which is the work point, and the light leaking from the optical fiber is detected by the control unit. To do.

  More specifically, in the core wire contrast operation, light generated from a light source provided on one end side of the optical fiber core wire is modulated by a modulator, and is incident on an optical line made of the optical fiber core wire as test light. This test light is extracted by the control head part of the control part provided at the control point. Specifically, the optical fiber core at the control point is bent by the control head unit, light leaking from the bent optical fiber core is received by the test light receiving unit, converted into an electrical signal, and supplied to the processing unit. The processing unit detects a signal modulated at the same frequency as the test light from the electrical signal, and turns on the lamp in the display lamp unit based on the detection signal. The lamp is turned on to confirm that the optical fiber is to be contrasted.

  In the above-described core wire contrast operation, it is necessary to minimize the transmission loss of the signal light caused by bending the optical fiber and to detect the test light by the core wire contrast device. Recently, a cord contrast device in which the wavelength of the test light is 1.65 μm has also been put into practical use, and leakage light due to bending of the test light is increased (for example, see Non-Patent Document 1).

  However, in the past, when actually comparing the cores, it is common to enter the test light into an unused core and check the core, and actually transmit the signal light. In the case where the test light is incident on the core wire (live wire), there is a problem that the test light does not enter the live wire because there is a problem that the test light affects the signal light. On the other hand, there is also a method of contrasting the core wire by detecting the signal light at the contrast part. However, in this case, since it is difficult to detect the signal light, there is a problem that the probability of the contrast is remarkably lowered. It was.

In order to make a test by injecting the test light into the live wire, conventionally, the test light can be made incident on the optical fiber core wire through which the signal light is transmitted by setting the test light to a frequency twice or more that of the signal light. There has also been proposed a method of contrasting the cores. However, it can be said that it is difficult with the current technology to create a device that receives a minute signal at a high frequency as described in this method.
JP 2003-65894 A K. Arakawa et al., “A Method for Identifying Single-mode Fibers in an Operating Fiber Cable System” (IWCS, pp. 88-93, 1989).

  Conventionally, when the test light is set to a frequency more than twice that of the signal light, the light receiving unit of the control unit cannot cope with the detection of high frequency while maintaining the conventional sensitivity, and the signal light becomes Mbs or Gbs. There is a problem that it is difficult to realize.

  The present invention has been made in view of the above, and an object of the present invention is to make an optical fiber core in which signal light is mixed even when the test light is different from the wavelength of the signal light and the frequency is twice or more that of the signal light. An object of the present invention is to provide a method and an apparatus for controlling a core line, which can accurately detect the presence or absence of test light even on a line and accurately perform the core line control.

In order to achieve the above object, the present invention as claimed in claim 1 is a method for contrasting optical fibers in which test light is incident on an optical fiber core, the test light is received at a control point, and the optical fiber core is contrasted. A first step of outputting light having a wavelength different from the wavelength of the signal light transmitted through the optical fiber core, and modulating the output light from the light source at a frequency more than twice the frequency of the signal light. And a second step in which the modulated light is intensity-modulated with a predetermined low-frequency signal, and the modulated intensity-modulated light is incident on the optical fiber as a test light, and light from the optical fiber at the control point. A third step of extracting, a fourth step of receiving test light from the extracted light and converting it into an electric signal, and a fifth step of outputting the electric signal as an intensity signal corresponding to the signal intensity of the test light The steps of this test light Receive degree signal, and summarized in that and a sixth step of displaying as the intensity of the test light.

In the first aspect of the present invention, light having a wavelength different from the wavelength of the signal light is output from the light source, and the output light is modulated at a frequency twice or more the frequency of the signal light and the modulated light is predetermined. Intensity modulation with a low-frequency signal, the modulated intensity-modulated light enters the optical fiber as test light, and the test light is received from the light extracted from the optical fiber at the control point and converted into an electrical signal. In order to output this electrical signal as an intensity signal corresponding to the signal intensity of the test light, receive the intensity signal of the test light, and display it on the display unit as the intensity of the test light. Even if the test light is incident on the fiber core and contrasted, the test light can be transmitted to the optical fiber without affecting the signal light, and the test light can be accurately transmitted as its intensity signal. Can be detected and displayed It is possible to perform mind-ray control to accurately.

Further, the present invention of claim 2 selectively extracts only light having the same wavelength as the test light from the light extracted from the optical fiber core wire in the third step in the invention of claim 1 , The gist is to supply to the fourth step.

In the present invention according to claim 2 , in order to selectively extract only the light having the same wavelength as the test light out of the light extracted from the optical fiber core wire, only the test light is accurately detected to detect the test light. Presence / absence can be displayed, and cord contrast can be accurately performed.

According to a third aspect of the present invention, there is provided a device for contrasting an optical fiber, wherein the test light is incident on an optical fiber, the test light is received at a control point, and the optical fiber is compared. A light source that outputs light having a wavelength different from the wavelength of the transmitted signal light, and the output light from the light source is modulated at a frequency that is at least twice the frequency of the signal light, and the modulated light is converted into a predetermined low-frequency signal. Modulating means that modulates the intensity and injects the modulated intensity-modulated light into the optical fiber as test light, extraction means that extracts light from the optical fiber at the control point, and test light from the extracted light a test light receiving means for converting into an electric signal by receiving and processing means for outputting a intensity signal corresponding to the electrical signal to the signal intensity of the test light, receives the intensity signal of the test light, as the intensity of the test light Display means to display The gist of the Rukoto.

According to the third aspect of the present invention, light having a wavelength different from the wavelength of the signal light is output from the light source, the output light is modulated at a frequency that is twice or more the frequency of the signal light, and the modulated light is predetermined. Intensity modulation with a low-frequency signal, the modulated intensity-modulated light enters the optical fiber as test light, and the test light is received from the light extracted from the optical fiber at the control point and converted into an electrical signal. In order to output this electrical signal as an intensity signal corresponding to the signal intensity of the test light, receive the intensity signal of the test light, and display it on the display unit as the intensity of the test light. Even if the test light is incident on the fiber core and contrasted, the test light can be transmitted to the optical fiber without affecting the signal light, and the test light can be accurately transmitted as its intensity signal. Can be detected and displayed It is possible to perform mind-ray control to accurately.

Further, according to a fourth aspect of the present invention, in the invention according to the third aspect , the light is connected between the extraction means and the test light receiving means, and is extracted from the optical fiber core by the extraction means. The gist of the invention is to have wavelength selection means for selectively extracting only light having the same wavelength as that of the test light and supplying the light to the test light receiving means.

In the present invention according to claim 4, since only the light having the same wavelength as the test light is selectively extracted from the light extracted from the optical fiber core wire, only the test light can be accurately detected to display the intensity. Therefore, it is possible to accurately perform contrast control.

As described above, according to the present invention, light having a wavelength different from the wavelength of the signal light is output from the light source, and the output light is modulated at a frequency more than twice the frequency of the signal light and the modulated light is predetermined. The modulation means that modulates the intensity with the low frequency signal of the optical signal and makes the modulated intensity modulated light incident on the optical fiber core as the test light, the extraction means that extracts the light from the optical fiber at the control point, and the extracted Test light receiving means for receiving the test light from the light and converting it into an electrical signal; outputting the electrical signal as an intensity signal corresponding to the signal intensity of the test light; receiving the intensity signal of the test light; Since the intensity is displayed on the display, even if the test light is incident on the optical fiber core wire through which the signal light is transmitted and the optical fiber is contrasted, the test light is not affected by the optical fiber core wire. Can enter and transmit The test light is detected in suitable probability as the intensity signal can be displayed, it is possible to perform the core wire control to accurately.

  Furthermore, according to the present invention, since only light having the same wavelength as the test light is selectively extracted from the light extracted from the optical fiber core wire, only the test light can be accurately detected and displayed, and the contrast of the core wires can be displayed. Can be performed accurately.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the overall configuration of a core line contrast device that performs a core line contrast method according to an embodiment of the present invention.

  The optical fiber contrast device of the embodiment shown in FIG. 1 is provided at the light source unit 3 and the control point 21 where the test light A of the optical fiber core constituting the optical fiber cable of the optical line 2 is incident. The test light A that has been transmitted through the optical fiber core is extracted from the optical fiber core of the optical line 2 and contrasted with the optical fiber core.

  The light source unit 3 includes a light source 31 that outputs light having a wavelength different from that of the signal light transmitted through the optical line 2, for example, 1.65 μm, and output light from the light source 31 that is twice the frequency of the signal light. A modulation unit 32 is configured to modulate at the above frequency, for example, a frequency of 2 GHz, and to make this modulated light enter the optical fiber core of the optical line 2 as test light A.

  The contrast device 4 includes a control head portion 41 that constitutes extraction means for extracting the test light A from the optical fiber core of the optical line 2, and a test for receiving the extracted test light A and converting it into an electrical signal. The test light receiving unit 42 constituting the light receiving means, the processing unit 43 constituting the processing means for processing this electrical signal and outputting it as a test light signal, and the test light A signal are received and the test light A is received. It is comprised from the display part 44 which comprises the display means to display. The reference head unit 41 extracts, as test light A, light that leaks out by bending the optical fiber core of the optical line 2 at the reference point 21.

  In the optical fiber contrast device configured as described above, when optical fiber cores are compared, light having a wavelength of, for example, 1.65 μm from the light source 31 of the light source unit 3 is twice as much as the signal light by the modulation unit 32. Modulation is performed at a frequency of 2 GHz, for example, and this modulated light is incident on the optical fiber core of the optical line 2 as test light A.

  In the control device 4, the optical fiber core of the optical line 2 is bent by the control head unit 41 at the control point 21, and the test light A is leaked from the optical fiber core by this bending. A is received by the test light receiver 42. The test light receiving unit 42 converts the test light A leaked from the optical fiber core wire into an electrical signal and supplies it to the processing unit 43.

  The processing unit 43 processes the electrical signal from the test light receiving unit 42 to process the test light A, and supplies the result to the display unit 44 as the test light A signal. The display unit 44 displays the signal of the test light A. As a result, by observing the signal displayed on the display unit 44, the observer can identify the test light A, and when the test light A is detected, the optical fiber core currently being contrasted It can be determined as a line.

  FIG. 2 is a diagram showing a configuration of a cord-line contrast device using a display lamp unit 45 instead of the display unit 44 in the embodiment of FIG. 1, and the other configurations and operations are the same as those in FIG. The same reference numerals are given to the constituent elements.

  As shown in FIG. 2, when the test light A is detected by using the display lamp unit 45 instead of the display unit 44, the lamp of the display lamp unit 45 is turned on. Therefore, the observer can easily determine that the optical fiber core wire is currently contrasted by observing the lighting of the lamp of the display lamp unit 45.

  FIG. 3 is a block diagram showing a configuration of a core line contrast device for performing a core line contrast method according to another embodiment of the present invention.

  3 differs only in that the intensity modulation unit 33 is newly connected to the output of the modulation unit 32 in the light source unit 3 in the core comparison device of the embodiment shown in FIG. Other configurations and operations are the same, and the same constituent elements are denoted by the same reference numerals except that the reference numeral of the light source unit is changed to 30.

  The intensity modulation unit 33 modulates the intensity of the modulated light modulated by the modulation unit 32 at a low frequency, for example, a low frequency of 1 Hz or less, and makes this intensity modulated light enter the optical fiber core of the optical line 2 as the test light A. Is. Note that the intensity modulation in this case is preferably not a rectangular wave but intensity modulation by a sine wave, that is, intensity modulation by a single frequency.

  In the optical fiber contrast device configured as described above, when optical fiber cores are compared, light having a wavelength of, for example, 1.65 μm output from the light source 31 of the light source unit 3 is converted into 2 of signal light by the modulation unit 32. The modulated light is modulated at 2 GHz, for example, 2 GHz, and the intensity modulation unit 33 further modulates the intensity of the modulated light at a low frequency, and the intensity-modulated light is incident on the optical fiber core of the optical line 2 as test light A.

  In the control unit 4, the optical fiber core of the optical line 2 is bent at the control point 21 by the control head unit 41, and the test light A leaked from the optical fiber core by this bending is received by the test light receiving unit 42. To do. The test light receiving unit 42 converts the test light A leaked from the optical fiber core wire into an electrical signal and supplies it to the processing unit 43.

  The processing unit 43 processes the electrical signal from the test light receiving unit 42 to perform the intensity processing of the test light A, and supplies the result to the display unit 44 as the intensity signal of the test light A. The display unit 44 displays the intensity of the test light A. As a result, when the observer observes the intensity display on the display unit 44 and detects that the intensity display is intensity-modulated with the same period as the test light A, the optical fiber core wire that is currently being contrasted Can be determined.

  That is, in the present embodiment, the intensity modulation unit 33 in the light source unit 30 modulates the intensity of the test light A, and the control unit 4 performs the intensity process of the test light A in the processing unit 43 and outputs the intensity signal of the test light A. Then, the display 44 displays the intensity of the test light A. Accordingly, when the observer detects that the intensity display on the display unit 44 displays the intensity with the same period as the test light A, the observer can determine that the optical fiber is to be compared.

  FIG. 4 is a diagram showing the configuration of the cord contrast device using the display lamp unit 45 instead of the display unit 44 in the embodiment of FIG. 3, and the other configurations and operations are the same as those in FIG. The same reference numerals are given to the constituent elements.

  As shown in FIG. 4, when the test light A is detected by using the display lamp unit 45 instead of the display unit 44, the lamp of the display lamp unit 45 is turned on. Therefore, the observer can easily determine that the optical fiber core wire is currently contrasted by observing the lighting of the lamp of the display lamp unit 45. Here, the processing unit 43 has a function of extracting a low-frequency component, and for example, when a signal of 1 Hz that is the same as the frequency of intensity modulation of the test light A is received, the lamp is turned on in the display lamp unit 45. By doing so, it is possible to easily identify the contrast of the test light A by lighting the lamp, and to facilitate the contrast work.

  FIG. 5 is a block diagram showing a configuration of a core line contrast device for performing a core line contrast method according to another embodiment of the present invention.

  5 is the wavelength of the test light A between the control head unit 41 of the control device 4 and the test light receiving unit 42 in the core control device of the embodiment shown in FIG. That is, the only difference is that a wavelength selection unit 62 that selectively extracts a wavelength of 1.65 μm is provided, the other configuration and operation are the same, except that the reference numeral is changed to 6. The same components are denoted by the same reference numerals.

  In the core wire contrast device of the embodiment configured as described above, when the optical fiber core wire is to be compared, light having a wavelength of, for example, 1.65 μm from the light source 31 of the light source unit 3 is converted by the modulation unit 32 into signal light. Modulation is performed at a double frequency, for example, 2 GHz, and this modulated light is incident on the optical fiber core of the optical line 2 as test light A.

  In the control device 4, the optical fiber core of the optical line 2 is bent at the control point 21 by the control head unit 41, and light is leaked from the optical fiber core by this bending, and the test light is emitted from the leaked light. A wavelength of 1.65 μm, which is the wavelength of A, is selectively extracted by the wavelength selector 62 and supplied to the test light receiver 42. The test light receiving unit 42 receives the test light A having the selected wavelength, that is, a wavelength of 1.65 μm, converts it into an electrical signal, and supplies it to the processing unit 43.

  The processing unit 43 processes the electrical signal from the test light receiving unit 42 to perform the intensity processing of the test light A, and supplies the result to the display unit 44 as the intensity signal of the test light A. The display unit 44 displays the intensity signal of the test light A. As a result, by observing the intensity signal displayed on the display unit 44, the observer can identify the test light A. When the test light A is detected, the optical fiber currently being contrasted It can be determined that it is a core line.

  Further, as shown in FIG. 6, when the test light A is detected by using the display lamp unit 45 instead of the display unit 44, the lamp of the display lamp unit 45 is lit with the intensity signal of the test light A. Like to do. Therefore, the observer can easily determine that the optical fiber core wire is currently contrasted by observing the lighting of the lamp of the display lamp unit 45.

  Specifically, as shown in FIG. 7, the wavelength selection unit 62 includes a wavelength selection filter 621 that selectively extracts and passes only light having a wavelength of 1.65 μm from the test light A. Accordingly, since the optical signal selectively extracted by the wavelength selection filter 621 is only the test light A having a wavelength of 1.65 μm, the test light A is displayed on the display unit via the test light receiving unit 42 and the processing unit 43. By displaying at 44, only the intensity of the test light A can be displayed accurately.

  Further, the wavelength selection unit can be configured by a slit unit 622, a diffraction grating unit 623, and a wavelength selection list unit 624, as indicated by reference numeral 620 in FIG.

  In the wavelength selection unit 620 configured as described above, the light leaked by bending the optical fiber core wire in the reference head unit 41 is directed by the slit unit 622 to reach the diffraction grating unit 623, and the diffraction grating In the part 623, it reflects in a different direction for every wavelength. Therefore, by providing the wavelength selection slit 624 in the direction in which the wavelength of 1.65, which is the wavelength of the test light A, is reflected, only light having the wavelength of the test light A can be selectively supplied to the processing unit 43. it can. Thereby, only the test light A can be detected accurately.

  FIG. 9 shows that the control head unit 41, the wavelength selection unit 62, and the test light receiving unit 42 are covered with the cover unit 67 in the cord control device of the embodiment shown in FIG. 5 and FIG. This is intended to improve the sensitivity of the cord contrast device of this embodiment.

It is a block diagram which shows the whole structure of the core line contrast apparatus which enforces the core line contrast method concerning one Embodiment of this invention. It is a block diagram which shows the structure at the time of using a display lamp part instead of a display part in the core wire contrast apparatus of embodiment shown in FIG. It is a block diagram which shows the structure of the core line contrast apparatus which enforces the core line contrast method concerning other embodiment of this invention. It is a block diagram which shows the structure at the time of using a display lamp part instead of a display part in the core wire contrast apparatus of embodiment shown in FIG. It is a block diagram which shows the structure of the core line contrast apparatus which enforces the core line contrast method concerning another embodiment of this invention. It is a block diagram which shows the structure at the time of using a display lamp part instead of a display part in the core wire contrast apparatus of embodiment shown in FIG. It is a figure which shows the structure of the specific example of the wavelength selection part used for the core line contrast apparatus of embodiment of FIG. 5 and FIG. It is a figure which shows the structure of another specific example of the wavelength selection part used for the core line contrast apparatus of embodiment of FIG. 5 and FIG. It is a figure which shows the structure at the time of covering the reference | standard head part, the wavelength selection part, and the test light light-receiving part with the cover part in the core line contrast apparatus of embodiment shown in FIG. 5 and FIG.

Explanation of symbols

2 Optical line 3 Light source unit 4, 6, 40, 60 Contrast unit 31 Light source 32 Modulating unit 33 Intensity modulating unit 41 Contrast head unit 42 Test light receiving unit 43 Processing unit 44 Display unit 45 Display lamp unit 62 Wavelength selection unit

Claims (4)

A method for contrasting optical fibers, in which test light is incident on an optical fiber, the test light is received at a control point, and the optical fiber is compared.
A first step of outputting from the light source light having a wavelength different from the wavelength of the signal light transmitted through the optical fiber;
The output light from the light source is modulated at a frequency that is twice or more the frequency of the signal light, and the modulated light is intensity-modulated with a predetermined low-frequency signal. A second step incident on the line;
A third step of extracting light from the optical fiber at the control point;
A fourth step of receiving test light from the extracted light and converting it into an electrical signal;
A fifth step of outputting as the intensity signal corresponding to the electrical signal to the signal intensity of the test light,
Receiving the intensity signals of the test light, core control method characterized by having a sixth step of displaying as the intensity of the test light. The third only the same light as the wavelength of the test light of the light extracted from the optical fiber in step selectively removed hearts of claim 1, wherein the supply to the fourth step Line contrast method. A core contrast device that enters test light into an optical fiber, receives the test light at a control point, and contrasts the optical fiber.
A light source that outputs light having a wavelength different from that of the signal light transmitted through the optical fiber;
The output light from the light source is modulated at a frequency that is twice or more the frequency of the signal light, and the modulated light is intensity-modulated with a predetermined low-frequency signal. Modulation means incident on the line;
Extraction means for extracting light from the optical fiber core at the control point;
Test light receiving means for receiving the test light from the extracted light and converting it into an electrical signal;
Processing means for outputting a intensity signal corresponding to the electrical signal to the signal intensity of the test light,
And a display means for receiving the intensity signal of the test light and displaying it as the intensity of the test light. Connected between the extracting means and the test light receiving means, and selectively extracting only light having the same wavelength as that of the test light from the light extracted from the optical fiber core by the extracting means. 4. The cord contrast device according to claim 3, further comprising wavelength selection means for supplying.

Images