JP6299259B2 - Optical fiber measuring device and optical fiber measuring method - Google Patents

Description

  The present invention relates to an optical fiber measuring apparatus and an optical fiber measuring method for inspecting transmission characteristics of an optical fiber core of an optical cable.

  Conventionally, the transmission characteristic inspection of an optical fiber accommodated in an optical cable has been performed by an OTDR measuring instrument (Optical Time Domain Reflectmeter). When a multi-core optical fiber is a measurement target, a measurement auxiliary device (MAS) is used. : Multiple Alignment System).

  As a measuring device for performing this transmission characteristic inspection, the same number of optical fiber cores as the number of fibers to be measured, which are tape core wires in which a plurality of optical fiber core wires are aligned and integrated in parallel, are integrated in parallel. Some include a measurement dummy fiber, which is a tape core, and an OTDR measuring device connected to each optical fiber of the measurement dummy fiber (see Patent Document 1). According to this measuring apparatus, a measurement dummy fiber connected to one OTDR measuring instrument is compared with a measuring apparatus that sequentially measures the optical fiber core of the fiber to be measured, and It is possible to measure the transmission characteristics of a plurality of optical fiber cores of a fiber in a short time with the same number of OTDR measuring instruments.

JP 2013-164398 A

  However, since the measuring apparatus described in Patent Document 1 requires the same number of expensive OTDR measuring instruments as the optical fiber core wire of the fiber to be measured, the equipment cost for optical fiber transmission characteristic inspection is greatly increased.

  An object of the present invention is to provide an optical fiber measuring apparatus and an optical fiber measuring method capable of measuring transmission characteristics of an optical fiber with high accuracy in a short time while suppressing facility costs.

An optical fiber measuring device according to the present invention is
An optical fiber measurement device for measuring transmission characteristics of a fiber to be measured, which is a tape core wire in which four optical fiber core wires are arranged in parallel and integrated,
A dummy fiber for measurement which is a tape core wire in which four optical fiber core wires of No. 1, No. 2, No. 3, No. 3 and No. 4 are arranged in parallel in order,
Each of the V-grooves of the V-groove block in which a plurality of V-grooves for holding the optical fiber cores are formed in parallel is abutted against each optical fiber core wire at one end of the dummy fiber for measurement and one end of the fiber to be measured. A measurement auxiliary device,
Two transmission characteristic measuring instruments connected to the other ends of the first and third optical fiber cores of the measurement dummy fiber and measuring the transmission characteristics of the optical fiber core of the measurement fiber;
One fiber detector connected to the other end of the fourth optical fiber core of the measurement dummy fiber and detecting the presence or absence of the optical fiber core of the measurement fiber;
A control device for controlling the operation of the transmission characteristic measuring device, the fiber detector, and the measurement auxiliary device;
With
The controller is
A first measurement in which the four optical fiber cores of the measurement target fiber and the four optical fiber cores of the measurement dummy fiber are abutted to perform measurement by the transmission characteristic measuring device and detection by the fiber detector; ,
The measurement dummy fiber is shifted by one center to the fourth center side, and the three optical fiber cores of the measurement target fiber and the first, second and third core optical fiber cores of the measurement dummy fiber Performing a second measurement in which the measurement is performed by the transmission characteristic measuring device and the detection by the fiber detector by matching the wires,
The transmission characteristics of the four optical fiber cores of the fiber to be measured are obtained from the measurement results of the transmission characteristic measuring instrument in the first measurement and the second measurement, and in the first measurement and the second measurement. From the measurement result of the transmission characteristic measuring device and the detection result of the fiber detector, it is determined whether or not the measurement dummy fiber is misaligned with respect to the fiber to be measured.

Moreover, the optical fiber measurement method according to the present invention includes:
The optical fiber core wire of the fiber to be measured, which is a tape core wire in which four optical fiber core wires are aligned in parallel, is held in a V-groove formed in parallel with the V-groove block. The optical fiber core wire of the measurement dummy fiber which is a tape core wire in which the four optical fiber core wires of the core number 3, the center number 3 and the number 4 core are arranged in parallel in order is held in the V groove. A transmission characteristic measuring device connected to the four optical fiber cores of the fiber to be measured and connected to the first and third optical fiber cores of the optical fiber of the fiber to be measured Measuring transmission characteristics, and performing a first measurement for detecting the presence or absence of the fiber to be measured with a fiber detector connected to the optical fiber core of the fourth core,
The measurement dummy fiber is shifted by one to the 4th core side, and the 3rd and 4th optical fiber core wires of the fiber to be measured and the 3 optical fiber cores of the measurement dummy fiber A second measurement is performed in which the measurement is performed by the transmission characteristic measuring device and the detection by the fiber detector by matching the wires,
The transmission characteristics of the four optical fiber cores of the fiber to be measured are obtained from the measurement results of the transmission characteristic measuring instrument in the first measurement and the second measurement, and in the first measurement and the second measurement. From the measurement result of the transmission characteristic measuring device and the detection result of the fiber detector, it is determined whether or not the measurement dummy fiber is misaligned with respect to the fiber to be measured.

  ADVANTAGE OF THE INVENTION According to this invention, the optical fiber measuring device and the optical fiber measuring method which can measure the transmission characteristic of an optical fiber with high precision in a short time can be provided, suppressing installation cost.

It is a block diagram which shows the structure of the optical fiber measuring device which concerns on one Embodiment of this invention. It is an enlarged view which shows the principal part of MAS of FIG. It is the schematic which shows the connection edge part of the optical fiber on the V-groove block of MAS of FIG. It is the schematic which shows the edge part of the to-be-measured fiber inserted in V groove | channel. It is a figure explaining the structure and measuring method of an optical fiber measuring apparatus, Comprising: (a) And (b) is a schematic block diagram, respectively. It is a flowchart explaining the flow of an optical fiber measuring method. It is a figure which shows the various measurement cases at the time of the measurement of an optical fiber.

<Outline of Embodiment of the Present Invention>
First, an outline of an embodiment of the present invention will be described.
One embodiment of an optical fiber measuring device according to the present invention is:
(1) An optical fiber measuring device for measuring transmission characteristics of a fiber to be measured, which is a tape core wire in which four optical fiber core wires are arranged in parallel and integrated,
A dummy fiber for measurement which is a tape core wire in which four optical fiber core wires of No. 1, No. 2, No. 3, No. 3 and No. 4 are arranged in parallel in order,
Each of the V-grooves of the V-groove block in which a plurality of V-grooves for holding the optical fiber cores are formed in parallel is abutted against each optical fiber core wire at one end of the dummy fiber for measurement and one end of the fiber to be measured. A measurement auxiliary device,
Two transmission characteristic measuring instruments connected to the other ends of the first and third optical fiber cores of the measurement dummy fiber and measuring the transmission characteristics of the optical fiber core of the measurement fiber;
One fiber detector connected to the other end of the fourth optical fiber core of the measurement dummy fiber and detecting the presence or absence of the optical fiber core of the measurement fiber;
A control device for controlling the operation of the transmission characteristic measuring device, the fiber detector, and the measurement auxiliary device;
With
The controller is
A first measurement in which the four optical fiber cores of the measurement target fiber and the four optical fiber cores of the measurement dummy fiber are abutted to perform measurement by the transmission characteristic measuring device and detection by the fiber detector; ,
The measurement dummy fiber is shifted by one center to the fourth center side, and the three optical fiber cores of the measurement target fiber and the first, second and third core optical fiber cores of the measurement dummy fiber Performing a second measurement in which the measurement is performed by the transmission characteristic measuring device and the detection by the fiber detector by matching the wires,
The transmission characteristics of the four optical fiber cores of the fiber to be measured are obtained from the measurement results of the transmission characteristic measuring instrument in the first measurement and the second measurement, and in the first measurement and the second measurement. From the measurement result of the transmission characteristic measuring device and the detection result of the fiber detector, it is determined whether or not the measurement dummy fiber is misaligned with respect to the fiber to be measured.
According to the configuration of (1), the transmission characteristics of all the optical fiber cores of the four fibers to be measured can be measured by performing the first measurement and the second measurement twice. In addition, two expensive transmission characteristic measuring instruments for measuring the transmission characteristics of the optical fiber core wire are sufficient for the measurement, and the equipment cost can be reduced.
Further, it is possible to reliably determine whether or not the measurement dummy fiber is misaligned with respect to the fiber to be measured from the measurement result of the transmission characteristic measuring device and the detection result of the fiber detector. In addition, as a fiber detector used for determining the presence or absence of an axis deviation, an inexpensive one that optically detects the presence or absence of an optical fiber core wire is used, or a transmission characteristic measuring device whose performance has deteriorated due to aging is effectively used. Can be economical.

(2) The transmission characteristic measuring instrument is configured to measure the return time and the amount of light of backscattered light from each part by making a light pulse incident on the optical fiber core of the fiber to be measured. It may be an OTDR measuring device that calculates a loss distribution, a loss value, and a defect position on the optical fiber core of the fiber.
According to the configuration of (2), the transmission characteristic of the optical fiber core of the fiber to be measured can be obtained with high accuracy by the transmission characteristic measuring device including the OTDR measuring device.

One embodiment of an optical fiber measurement method according to the present invention is:
(3) The optical fiber core wire of the fiber to be measured, which is a tape core wire in which four optical fiber core wires are aligned in parallel, is held in a V groove formed in parallel with the V groove block,
The optical fiber core wire of the measurement dummy fiber, which is a tape core wire in which the four optical fiber core wires of the first core, the second core, the third core, and the fourth core are arranged in parallel in order, is V A transmission characteristic measuring instrument connected to the first and third optical fiber cores, held in a groove, butted against the four optical fiber cores of the fiber to be measured, and connected to the first and third optical fiber cores. Measuring the transmission characteristics of the optical fiber core, and performing a first measurement for detecting the presence or absence of the fiber to be measured by a fiber detector connected to the optical fiber core of the fourth core,
The measurement dummy fiber is shifted by one to the 4th core side, and the optical fiber cores of the 2nd, 3rd, and 4th cores of the measured fiber and three optical fiber cores of the measurement dummy fiber A second measurement is performed in which the measurement is performed by the transmission characteristic measuring device and the detection by the fiber detector by matching the wires,
The transmission characteristics of the four optical fiber cores of the fiber to be measured are obtained from the measurement results of the transmission characteristic measuring instrument in the first measurement and the second measurement, and in the first measurement and the second measurement. From the measurement result of the transmission characteristic measuring device and the detection result of the fiber detector, it is determined whether or not the measurement dummy fiber is misaligned with respect to the fiber to be measured.
According to the configuration of (3), the transmission characteristics of all the optical fiber cores of the four fibers to be measured can be measured by performing the first measurement and the second measurement twice. In addition, since two expensive transmission characteristic measuring instruments for measuring the transmission characteristic of the optical fiber core wire are sufficient for the measurement, the equipment cost can be suppressed.
Further, it is possible to reliably determine whether or not the measurement dummy fiber is misaligned with respect to the fiber to be measured from the measurement result of the transmission characteristic measuring device and the detection result of the fiber detector. In addition, as a fiber detector used for determining the presence or absence of an axis deviation, an inexpensive one that optically detects the presence or absence of an optical fiber core wire is used, or a transmission characteristic measuring device whose performance has deteriorated due to aging is effectively used. Can be economical.

<Details of Embodiment of the Present Invention>
Hereinafter, an example of an embodiment of an optical fiber measuring device and a measuring method concerning the present invention is described with reference to drawings. In addition, this invention is not limited to these illustrations, is shown by the claim, and intends that all the changes within the meaning and range equivalent to a claim are included.

FIG. 1 is a block diagram showing a configuration of an optical fiber measuring apparatus 10 according to an embodiment of the present invention.
As shown in FIG. 1, the optical fiber measurement device 10 of the present embodiment is mainly used for measurement on an OTDR measurement device 11A and a fiber detector 11B to which one end side of a measurement dummy fiber F0 is connected, and a V-groove block 14. A measurement auxiliary device (MAS) 12 that abuts the dummy fiber F0 and the measurement fiber F1 and a control device 13 that controls the operation of the OTDR measurement device 11A, the fiber detector 11B, and the MAS 12 are provided. Two OTDR measuring devices 11A are installed, and one fiber detector 11B is installed.

  The fibers to be measured F1 are arranged in parallel with four optical fiber cores in contact with each other on one plane, and the outer periphery thereof is integrally covered with a tape core resin. In the optical fiber core, a glass fiber composed of a core and a clad is disposed at the center, and the outer periphery thereof is coated with a resin including a colored layer.

  The OTDR measuring instrument 11A makes a light pulse incident on the optical fiber core of the fiber for measurement F1, and measures the return time and the amount of light of the backscattered light from each part, whereby the optical fiber core of the fiber for measurement F1. The loss distribution, loss value (loss value), defect position, etc. on the line are calculated. If there is a local high loss in the optical fiber core of the fiber F1 to be measured, it appears as a change in inclination (step amount, section loss value) on the OTDR waveform, and such a change in inclination is detected as a step abnormality. And recognized as a section loss abnormality.

  The fiber detector 11B detects the presence or absence of the optical fiber core wire of the measurement target fiber F1 at the facing position. The fiber detector 11B does not need to measure the transmission characteristics of the optical fiber core wire of the fiber to be measured F1. That is, as the fiber detector 11B, an inexpensive one that can optically detect the presence or absence of the optical fiber core wire can be used. Moreover, as this fiber detector 11B, it is also possible to use an OTDR measuring device with reduced performance. In the present embodiment, an OTDR measuring device whose performance is lowered is used as the fiber detector 11B.

  The OTDR measuring instrument is caused by aging due to long-term use, etc., and the waveform noise increases with the deterioration of the LD (Laser Diode) light source, and local small waveform fluctuations are observed in the measured OTDR waveform There is. In this case, it cannot be determined whether the fiber characteristic or waveform noise is caused, and this impedes product quality assurance. Therefore, this OTDR measuring instrument cannot be used for measuring the transmission characteristic of the optical fiber. Become.

  However, even with an OTDR measuring instrument whose performance has deteriorated due to such aging, if LSA (Least Square Approximation) is applied to the OTDR waveform, the measurement dummy fiber F0 and the device under test are measured. As for the connection loss value with the optical fiber F1, it is possible to obtain an appropriate measurement value.

  In other words, in the present embodiment, an OTDR measuring device with reduced performance is used as the fiber detector 11B, and based on the data connection loss value of the fiber detector 11B, the presence / absence of the optical fiber core wire of the fiber F1 to be measured is determined. Detect. Therefore, the data obtained by the fiber detector 11B uses only the connection loss value and does not use it as the quality assurance data of the fiber F1 to be measured.

  The control device 13 is installed with inspection software for transmission characteristic inspection. The control device 13 transmits a control signal 15A to the OTDR measuring instrument 11A to control the operation of the measuring instrument itself, receives the measurement data 16A acquired from the OTDR measuring instrument 11A, analyzes the measurement data 16A, and passes or fails. Make a decision. The control device 13 transmits a control signal 15B to the fiber detector 11B to control the operation of the measuring device itself, receives the detection data 16B acquired from the fiber detector 11B, and determines the optical fiber from the connection loss value. The presence or absence of a core wire is determined. Further, the control device 13 transmits a control signal 17 to the MAS 12 to control the operation of the movable head 20 to be described later, and to each of the fibers to be measured F1 positioned at the connection portion P on the V groove block 14. The other end side of the measurement dummy fiber F0 is butted.

FIG. 2 is an enlarged view showing a main part of the MAS 12 of FIG.
As shown in FIG. 2, the MAS 12 has a movable head 20 that moves on the guide rail 22, a tape holder 23 that holds four fibers to be measured F <b> 1, and a fiber to be measured F <b> 1 for each tape holder 23. And a plurality of rows of stages 24. In front of each stage 24, a V-groove block 14 having a plurality of V-grooves Vm (see FIGS. 3 and 4) is provided. The stage 24 is inclined by a predetermined angle toward the V-groove block 14.

FIG. 3 is a schematic view showing a connecting end portion of the optical fiber core wire on the V groove block 14 of the MAS 12 of FIG. FIG. 4 is a schematic diagram showing the end of the fiber for measurement F1 inserted into the V-groove Vm.
As shown in FIGS. 3 and 4, valley portions 31 and mountain portions 32 are alternately formed in the V groove block 14, so that the 0th groove Vm0, the first groove Vm1, and the second groove Vm2 are formed. A plurality of V grooves Vm such as a third groove Vm3, a fourth groove Vm4, a fifth groove Vm5, and a sixth groove Vm6 are formed. The pitch X of the V-groove Vm is adjacent to the glass fibers to be measured Gh1 to Gh4 exposed by peeling a predetermined length of resin including the colored layer of the optical fiber core F1a constituting the four fibers to be measured F1. The distance between the glass fibers coincides with, for example, the distance W between the central axes of the first glass fiber Gh1 and the second glass fiber Gh2. Therefore, the minimum moving distance of the movable head 20 in the direction of the arrow 25 is set to coincide with the pitch X of the V groove Vm.

  As shown in FIG. 2, the movable head 20 is set so as to be movable in the direction of the arrow 25 by the guide rail 22. On the movable head 20, a dummy holder 21 for holding the measurement dummy fiber F0 is provided. The dummy holder 21 is set to be movable by a predetermined distance in the direction of an arrow 26 perpendicular to the direction of the arrow 25 that is the direction of movement of the movable head 20 along the guide rail 22. The dummy holder 21 holds four measurement dummy fibers F0.

  The optical fiber cores F1a of the fiber F1 to be measured are arranged in parallel in a state where the four optical fiber cores F1a are adjacent to each other on one plane, and the outer periphery thereof is integrally covered with the tape core resin and tape. It is the state of the core. The optical fiber core wire F1a of the fiber F1 to be measured has the first core optical fiber core wire F1a1, the second core optical fiber core wire F1a2, the third core optical fiber core wire F1a3 and the fourth core in order from one side of the array. The optical fiber core is F1a4.

  The measurement dummy fiber F0 has four optical fiber cores F0a, the same number as the number of optical fiber cores F1a of the fiber to be measured F1. Similar to the fiber for measurement F1, the optical fiber core wire F0a of the measurement dummy fiber F0 has a glass fiber composed of a core and a clad at the center, and the outer periphery thereof is coated with a fiber resin containing a colored layer. In the measurement dummy fiber F0, the pitch of the optical fiber core wire F0a is the same as that of the optical fiber core wire F1a of the fiber F1 to be measured. The optical fiber core wire F0a of the measurement dummy fiber F0 is, in order from one side of the array, the first core optical fiber core wire F0a1, the second core optical fiber core wire F0a2, the third core optical fiber core wire F0a3 and the fourth core. The optical fiber core is F0a4.

  The dummy fiber F0 for measurement exposes the dummy glass fibers Gd1 to Gd4 having a predetermined length by peeling off the fiber resin at the tip of the optical fiber core wire F0a before being attached to the dummy holder 21. The measurement dummy fiber F0 is attached to a predetermined position of the dummy holder 21 on the movable head 20. Therefore, the moving distance of the dummy holder 21 in the direction of the arrow 26 is the distance between the tip of the dummy glass fibers Gd1 to Gd4 and the tip of the glass fibers Gh1 to Gh4 to be measured arranged on the V-groove block 14. Set to match Y.

FIG. 5 is a diagram for explaining the configuration and measurement method of the optical fiber measuring apparatus 10, and (a) and (b) are schematic configuration diagrams.
As shown in FIG. 5A, a connecting single-core optical fiber 41 is connected to the optical fiber core wire F0a. The first-core optical fiber core wire F0a1 and the third-core optical fiber core wire F0a3 are each connected to the OTDR measuring instrument 11A via the connecting single-core optical fiber 41. The 4th core optical fiber core wire F0a4 is connected to the fiber detector 11B through the connection single core optical fiber 41. The connecting single-core optical fiber 41 connected to the second-core optical fiber core wire F0a2 is in a state where nothing is connected to the end thereof. The single-core optical fiber 41 for connection need not be connected to the second-core optical fiber core wire F0a2.

Next, an optical fiber measurement method according to this embodiment will be described.
FIG. 6 is a flowchart for explaining the flow of the optical fiber measurement method.
In the present embodiment, the control device 13 controls the operation of the OTDR measuring instrument 11A, the fiber detector 11B, and the MAS 12, and measures the fiber to be measured F2 in two steps, and then determines whether or not remeasurement due to axial deviation is necessary. judge.

(Step S01)
First, the 1st measurement by the following procedures is performed.
The glass fibers to be measured Gh1 to Gh4 of the optical fibers F1a1 to F1a4 of the fiber to be measured F1 are held in the first groove Vm1 to the fourth groove Vm4 of the V groove block 14 (see FIGS. 3 and 4).
As shown in FIG. 5A, the dummy glass fibers Gd1 to Gd4 of the optical fiber core wires F0a1 to F0a4 of the measurement dummy fiber F0 are held in the first groove Vm1 to the fourth groove Vm4, and the fiber to be measured The glass fibers to be measured Gh1 to Gh4 of the optical fiber cores F1a1 to F1a4 of F1 are opposed to each other.

  The measurement dummy fiber F0 is moved to the measured fiber F1 side, and the dummy glass fibers Gd1 to Gd4 are brought into contact with the measured glass fibers Gh1 to Gh4.

  In this state, with the OTDR measuring instrument 11A connected to the first core optical fiber core wire F0a1 and the third core optical fiber core wire F0a3 of the measurement dummy fiber F0, the first core optical fiber core wire F1a1 of the fiber F1 to be measured And the transmission characteristic of the 3rd core optical fiber core wire F1a3 is measured.

Based on the measurement result of the OTDR measuring instrument 11A in the first measurement, the control device 13 determines all the quality assurance required for product quality in the first-core optical fiber core F1a1 and the third-core optical fiber core F1a3 of the fiber F1 to be measured. Get the transmission characteristics to be measured data.
Further, the control device 13 acquires only the connection loss value from the data of the fiber detector 11B connected to the fourth optical fiber core wire F0a4 of the measurement dummy fiber F0.

(Step S02)
Next, the second measurement according to the following procedure is performed.
As shown in FIG. 5B, the dummy glass fibers Gd1 to Gd4 of the optical fiber core wires F0a1 to F0a4 are moved to the fourth core optical fiber core wire F0a4 by moving the measurement dummy fiber F0 toward the fourth core optical fiber core wire F0a4. The dummy glass fibers Gd1 to Gd3 of the optical fiber core wires F0a1 to F0a3 of the measurement dummy fiber F0 are held in the second groove Vm2 to the fifth groove Vm5, and the optical fiber core wires F1a2 to F1a4 of the measurement fiber F1 are covered. The measurement glass fibers Gh2 to Gh4 are opposed to each other.

  The measurement dummy fiber F0 is moved to the measured fiber F1 side, and the dummy glass fibers Gd1 to Gd3 are butted against the measured glass fibers Gh2 to Gh4. At this time, the dummy glass fiber Gd4 of the fourth-core optical fiber F0a4 of the measurement dummy fiber F0 is No. 5 in which none of the optical fiber cores F1a1 to F1a4 of the measurement-target fiber F1 is arranged at the facing position. It is held in the groove Vm5. Therefore, nothing is abutted against the dummy glass fiber Gd4 of the fourth core optical fiber core wire F0a4.

  In this state, with the OTDR measuring instrument 11A connected to the first core optical fiber core wire F0a1 and the third core optical fiber core wire F0a3 of the measurement dummy fiber F0, the second core optical fiber core wire F1a2 of the fiber F1 to be measured And the transmission characteristic of the 4th core optical fiber core wire F1a4 is measured.

Based on the measurement result of the OTDR measuring instrument 11A in the second measurement, the control device 13 determines all the quality assurance required for product quality in the second-core optical fiber F1a2 and the fourth-core optical fiber F1a4 of the fiber F1 to be measured. Get the transmission characteristics to be measured data.
Further, the control device 13 acquires only the apparent connection loss value from the data of the fiber detector 11B connected to the fourth optical fiber core wire F0a4 of the measurement dummy fiber F0.

(Step S03)
A re-measurement necessity determination is performed based on the following data from the fiber detector 11B.
The control device 13 determines whether or not the detection result of the fiber detector 11B obtained in the first measurement (step S01) and the second measurement (step S02) is a normal pattern that is a predetermined pattern.

  In the first measurement, the fourth-core optical fiber F0a4 of the measurement dummy fiber F0 is abutted against the fourth-core optical fiber F1a4 of the measurement fiber F1. That is, the fourth-core optical fiber core wire F1a4 has a position opposite to the fourth-core optical fiber core wire F0a4. For this reason, in the data from the fiber detector 11B, a small connection loss value (for example, +5 dB or less) is obtained. Based on this connection loss value, it is detected that the fourth-core optical fiber F1a4 has a position opposite to the fourth-core optical fiber F0a4.

  On the other hand, in the second measurement, nothing is abutted against the fourth-core optical fiber core wire F0a4 of the measurement dummy fiber F0. That is, none of the optical fiber core wires F1a1 to F1a4 is provided at a position opposite to the fourth core optical fiber core wire F0a4. For this reason, in the data from the fiber detector 11B, an excessive connection loss value (for example, +10 dB or more) is obtained. Then, based on this connection loss value, it is detected that none of the optical fiber cores F1a1 to F1a4 is provided at a position opposite to the fourth core optical fiber core F0a4.

  Based on the data from the fiber detector 11B, the control device 13 determines whether or not the connection loss value is a normal pattern that is small in the first measurement and excessive in the second measurement. If the connection loss value deviates from the normal pattern (step S03: No), the measuring device 13 determines that an axis misalignment has occurred, and starts measurement of the fiber for measurement F1 from the first measurement as a remeasurement requirement. Try again.

(Step S04)
Next, a re-measurement necessity determination is performed based on data from the following OTDR measuring instrument 11A.
The control device 13 determines whether or not there is an abnormality in the detection results of the OTDR measuring instrument 11A obtained in the first measurement (step S01) and the second measurement (step S02).

  In the first measurement, the first core optical fiber core wire F0a1 and the third core optical fiber core wire F0a3 of the measurement dummy fiber F0 are the first core optical fiber core wire F1a1 and the third core optical fiber of the fiber F1 to be measured. It is matched with the core wire F1a3. In the second measurement, the first core optical fiber core wire F0a1 and the third core optical fiber core wire F0a3 of the measurement dummy fiber F0 are the second core optical fiber core wires F1a2 and fourth core of the fiber F1 to be measured. It is abutted against the optical fiber core wire F1a4. For this reason, if the data from the OTDR measuring instrument 11A is normal, a measurement abnormality that causes an excessive connection loss value does not occur.

  Therefore, the control device 13 determines whether there is a measurement abnormality in which the connection loss value is excessive based on the data from the OTDR measuring device 11A. If there is a measurement abnormality (step S04: Yes), the measuring device 13 determines that an axis deviation has occurred, and repeats the measurement of the measurement target fiber F1 from the first measurement as the need for remeasurement.

Next, various measurement cases in the optical fiber measurement method according to the present embodiment and re-measurement necessity determination in each measurement case will be described.
FIG. 7 is a diagram showing various measurement cases when measuring an optical fiber.
As shown in FIG. 7, in the optical fiber measurement device 10 according to the present embodiment, there are mainly a normal case and abnormal cases 1 to 6 in which an axial deviation occurs as measurement cases. The abnormal cases 1 to 3 are cases in which the measurement dummy fiber F0 is off-axis toward the fourth-core optical fiber core wire F0a4. In abnormal cases 4 to 6, the measurement dummy fiber F0 is the first-core optical fiber. This is a case where the axis is shifted to the side of the core wire F0a1.

(Normal case)
This is a case where no axial deviation occurs in either the first measurement or the second measurement.

  In this normal case, the connection loss value based on the data of the fiber detector 11B is a normal pattern that is small in the first measurement and excessive in the second measurement.

  In this normal case, the connection loss values based on the data of the two OTDR measuring devices 11A are not excessive in the first measurement and the second measurement.

  Therefore, in the normal case, it is determined that there is no axis deviation (step S03: Yes, step S04: No), and the measurement on the measurement target fiber F1 is normally terminated.

(Abnormal case 1)
Abnormal case 1 is a case in which, in the first measurement, the measurement dummy fiber F0 is shifted by one center axis toward the fourth-core optical fiber core wire F0a4.

  In this abnormal case 1, since the connection loss value based on the data of the fiber detector 11B becomes excessive in the first measurement and excessive in the second measurement, it deviates from the normal pattern.

  Therefore, in the abnormal case 1, it is determined that there is an axis deviation (step S03: No), and remeasurement is performed.

  In this abnormal case 1, the waveform data of the two OTDR measuring instruments 11A are completely coincident that does not normally occur in the first measurement and the second measurement. From this, it is also possible to determine that an axis deviation has occurred.

(Abnormal case 2)
Abnormal case 2 is a case in which, in the second measurement, the measurement dummy fiber F0 is shifted by one center axis toward the fourth-core optical fiber core wire F0a4.

  In this abnormal case 2, the connection loss value based on the data of the fiber detector 11B is a normal pattern that is small in the first measurement and excessive in the second measurement.

  However, in this abnormal case 2, in the second measurement, the connection loss value based on the data of the OTDR measuring instrument 11A to which the third-core optical fiber F0a3 of the measurement dummy fiber F0 is connected becomes excessive, and there is a measurement abnormality. It is determined.

  Therefore, in the abnormal case 2, it is determined that there is an axis deviation (step S04: Yes), and remeasurement is performed.

(Abnormal case 3)
In the abnormal case 3, in the first measurement, the measurement dummy fiber F0 is shifted by one axis toward the fourth-core optical fiber core line F0a4, and then in the second measurement, the measurement dummy fiber F0 is the fourth-core optical fiber. This is a case of moving one core toward the core wire F0a4.

  In this abnormal case 3, since the connection loss value based on the data of the fiber detector 11B becomes excessive in the first measurement and excessive in the second measurement, it deviates from the normal pattern.

  Therefore, in abnormal case 3, it is determined that there is an axis deviation (step S03: No), and remeasurement is performed.

  In this abnormal case 3, it is determined that there is a measurement abnormality because the connection loss value based on the data of the OTDR measuring instrument 11A to which the third-core optical fiber F0a3 of the measurement dummy fiber F0 is connected becomes excessive. It is also possible.

(Abnormal Case 4)
In the abnormal case 4, in the first measurement, the measurement dummy fiber F0 is shifted by one axis toward the first-core optical fiber core line F0a1, and then in the second measurement, the measurement dummy fiber F0 is the fourth-core optical fiber. This is a case where two cores have moved to the side of the core wire F0a4.

  In this abnormal case 4, the connection loss value based on the data of the fiber detector 11B is a normal pattern that becomes small in the first measurement and excessive in the second measurement.

  However, in this abnormal case 4, in the first measurement, the connection loss value based on the data of the OTDR measuring device 11A to which the first-core optical fiber core wire F0a1 of the measurement dummy fiber F0 is connected becomes excessive, and there is a measurement abnormality. It is determined.

  Therefore, in the abnormal case 4, it is determined that there is an axis deviation (step S04: Yes), and remeasurement is performed.

(Abnormal case 5)
The abnormal case 5 is a case in which the measurement dummy fiber F0 is displaced in the second measurement because the measurement dummy fiber F0 does not move toward the fourth-core optical fiber core wire F0a4.

  In this abnormal case 5, since the connection loss value based on the data of the fiber detector 11B is small in the first measurement and small in the second measurement, it is out of the normal pattern.

  Therefore, in the abnormal case 5, it is determined that there is an axis deviation (step S03: No), and remeasurement is performed.

  In this abnormal case 5, the waveform data of the two OTDR measuring devices 11A are completely coincident that does not normally occur in the first measurement and the second measurement. From this, it is also possible to determine that an axis deviation has occurred.

(Abnormal Case 6)
In the abnormal case 6, in the first measurement, the measurement dummy fiber F0 is shifted by one center axis toward the first-core optical fiber core line F0a1, and then in the second measurement, the measurement dummy fiber F0 is the fourth-core optical fiber. This is a case of moving one core toward the core wire F0a4.

  In this abnormal case 6, since the connection loss value based on the data of the fiber detector 11B is small in the first measurement and small in the second measurement, it is out of the normal pattern.

  Therefore, in the abnormal case 6, it is determined that there is an axis deviation (step S03: No), and remeasurement is performed.

  In this abnormal case 6, since the connection loss value based on the data of the OTDR measuring instrument 11A to which the first-core optical fiber F0a1 of the measurement dummy fiber F0 is connected is excessive, it is determined that there is a measurement abnormality. It is also possible.

(Other measurement cases)
As another measurement case, both or one of the first-core optical fiber core wire F0a1 and the third-core optical fiber core wire F0a3 of the measurement dummy fiber F0 connected to the OTDR measuring instrument 11A is shifted by one core. Thus, there is a possibility that the second-core optical fiber F0a2 is originally held in the second groove Vm2 and the fourth-core optical fiber core F0a4 is likely to enter into the fourth groove Vm4 originally held.

  However, the 2nd core optical fiber core wire F0a2 and the 4th core optical fiber core wire F0a4 are originally held second groove Vm2 rather than the 1st core optical fiber core wire F0a1 and the 3rd core optical fiber core wire F0a3. And is easily held in the fourth groove Vm4. Therefore, the first-core optical fiber core wire F0a1 and the third-core optical fiber core wire F0a3 are not held in the second groove Vm2 or the fourth groove Vm4, but are separated from any V-groove Vm. It becomes.

  Therefore, the first-core optical fiber core wire F0a1 and the third-core optical fiber core wire F0a3 are not abutted with any of the optical fiber core wires F1a of the fiber for measurement F1. For this reason, in the case of this measurement case, since the connection loss value based on the data of the OTDR measuring instrument 11A to which the first-core optical fiber core wire F0a1 or the third-core optical fiber core wire F0a3 is connected becomes excessive, the measurement abnormality It is possible to determine that there is.

  Similarly, the first-core optical fiber core wire F0a1 is originally formed by shifting one or both of the second-core optical fiber core wire F0a2 and the fourth-core optical fiber core wire F0a4 of the measurement dummy fiber F0. The held first groove Vm1 and the third-core optical fiber core wire F0a3 may enter the third-groove Vm3 originally held by mistake.

  However, the first core optical fiber core wire F0a1 and the third core optical fiber core wire F0a3 are originally held in the first groove Vm1 rather than the second core optical fiber core wire F0a2 and the fourth core optical fiber core wire F0a4. And it is easy to be held in the third groove Vm3. Therefore, the second-core optical fiber core wire F0a2 and the fourth-core optical fiber core wire F0a4 are not held in the first groove Vm1 and the third groove Vm3, and are separated from any V-groove Vm. It becomes.

  Therefore, even if the second core optical fiber core wire F0a2 and the fourth core optical fiber core wire F0a4 are misaligned, the first core optical fiber core wire F0a1 and the third core optical fiber core wire F0a3 are the normal first The groove is held in the groove No. Vm1 and the third groove Vm3. In this case, appropriate measurement data is obtained by the two OTDR measuring devices 11A to which the first-core optical fiber core wire F0a1 and the third-core optical fiber core wire F0a3 are connected.

  As described above, according to the optical fiber measuring apparatus and the measuring method according to the present embodiment, all four fibers to be measured F1 are measured by performing the first measurement and the second measurement twice. The transmission characteristics of the optical fiber core wire F1a can be measured. In addition, the measurement is configured to use only two OTDR measuring instruments 11A, which are expensive transmission characteristic measuring instruments for measuring the transmission characteristics of the optical fiber core wire F1a.

  Further, from the measurement result of the OTDR measurement device 11A and the detection result of the fiber detector 11B, it is possible to reliably determine whether or not the measurement dummy fiber F0 is misaligned with respect to the fiber F1 to be measured. Moreover, as the fiber detector 11B used for determining the presence / absence of the axis deviation, an inexpensive one that optically detects the presence / absence of the optical fiber core is used, or an OTDR measuring device whose performance has deteriorated due to aging is effectively used. Can be economical.

  As described above, according to the present embodiment, it is possible to measure the transmission characteristics of the fiber F1 to be measured with high accuracy in a short time while suppressing the equipment cost.

  In the above embodiment, the dummy glass fiber Gd2 of the second-core optical fiber core wire F0a2 of the measurement fiber F0 is a glass fiber having a core and a clad. However, as this dummy glass fiber Gd2, another dummy glass is used. As long as it has the same outer diameter as the fibers Gd1, Gd3, Gd4, it may not be composed of a core and a clad.

10: Optical fiber measuring device 11A: OTDR measuring device (transmission characteristic measuring device)
11B: Fiber detector 12: Measurement auxiliary device 13: Control device 14: V groove block F0: Dummy fiber for measurement F0a1 to F0a4: Optical fiber core wire F1: Fibers to be measured F1a1 to F1a4: Optical fiber core wire Vm: V groove

Claims (3)

An optical fiber measurement device for measuring transmission characteristics of a fiber to be measured, which is a tape core wire in which four optical fiber core wires are arranged in parallel and integrated,
A dummy fiber for measurement which is a tape core wire in which four optical fiber core wires of No. 1, No. 2, No. 3, No. 3 and No. 4 are arranged in parallel in order,
Each of the V-grooves of the V-groove block in which a plurality of V-grooves for holding the optical fiber cores are formed in parallel is abutted against each optical fiber core wire at one end of the dummy fiber for measurement and one end of the fiber to be measured. A measurement auxiliary device,
Two transmission characteristic measuring instruments connected to the other ends of the first and third optical fiber cores of the measurement dummy fiber and measuring the transmission characteristics of the optical fiber core of the measurement fiber;
One fiber detector connected to the other end of the fourth optical fiber core of the measurement dummy fiber and detecting the presence or absence of the optical fiber core of the measurement fiber;
A control device for controlling the operation of the transmission characteristic measuring device, the fiber detector, and the measurement auxiliary device;
With
The controller is
A first measurement in which the four optical fiber cores of the measurement target fiber and the four optical fiber cores of the measurement dummy fiber are abutted to perform measurement by the transmission characteristic measuring device and detection by the fiber detector; ,
The measurement dummy fiber is shifted by one center to the fourth center side, and the three optical fiber cores of the measurement target fiber and the first, second and third core optical fiber cores of the measurement dummy fiber Performing a second measurement in which the measurement is performed by the transmission characteristic measuring device and the detection by the fiber detector by matching the wires,
The transmission characteristics of the four optical fiber cores of the fiber to be measured are obtained from the measurement results of the transmission characteristic measuring instrument in the first measurement and the second measurement, and in the first measurement and the second measurement. An optical fiber measuring device for determining whether or not the measurement dummy fiber is misaligned with respect to the fiber to be measured from the measurement result of the transmission characteristic measuring device and the detection result of the fiber detector.   The transmission characteristic measuring instrument makes an optical pulse incident on the optical fiber core wire of the fiber to be measured, and measures the return time and the amount of light of backscattered light from each part, whereby the measurement fiber of the fiber to be measured The optical fiber measuring device according to claim 1, wherein the optical fiber measuring device is an OTDR measuring device that calculates a loss distribution, a loss value, and a defect position on the optical fiber. Holding the optical fiber core of the fiber to be measured, which is a tape core integrated with four optical fiber cores arranged in parallel, in a V-groove formed in parallel with the V-groove block;
The optical fiber core wire of the measurement dummy fiber, which is a tape core wire in which the four optical fiber core wires of the first core, the second core, the third core, and the fourth core are arranged in parallel in order, is V A transmission characteristic measuring instrument connected to the first and third optical fiber cores, held in a groove, butted against the four optical fiber cores of the fiber to be measured, and connected to the first and third optical fiber cores. Measuring the transmission characteristics of the optical fiber core, and performing a first measurement for detecting the presence or absence of the fiber to be measured by a fiber detector connected to the optical fiber core of the fourth core,
The measurement dummy fiber is shifted by one to the 4th core side, and the 3rd and 4th optical fiber core wires of the fiber to be measured and the 3 optical fiber cores of the measurement dummy fiber A second measurement is performed in which the measurement is performed by the transmission characteristic measuring device and the detection by the fiber detector by matching the wires,
The transmission characteristics of the four optical fiber cores of the fiber to be measured are obtained from the measurement results of the transmission characteristic measuring instrument in the first measurement and the second measurement, and in the first measurement and the second measurement. An optical fiber measurement method for determining whether or not the measurement dummy fiber is misaligned with respect to the fiber to be measured from the measurement result of the transmission characteristic measuring device and the detection result of the fiber detector.

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