JP2016057297A - Component for measurement and measuring method of optical fiber transmission body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a component for measurement of an optical fiber transmission body and a measuring method of the optical fiber transmission body capable of efficiently measuring an optical characteristic of a plurality of core parts of the optical fiber transmission body having the core parts.SOLUTION: The component for measurement inputs test light to an optical fiber transmission body having a plurality of core parts, a first end, and a second end. The component for measurement includes: a first component that is connected to the first end, and has a light input waveguide core part connected to a first core part of the plurality of core parts; and a second component that is connected to the second end, and has a first connection waveguide core part for interconnecting the first core part and the second core part, of the plurality of core parts, at the second end.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an optical fiber transmission body measuring part and a measuring method.

  As a means to dramatically increase communication capacity, a space multiplexing transmission system (Space-based transmission system) that uses a multi-core fiber in which multiple cores exist in parallel in the cladding as an optical fiber transmitter constituting the transmission path Division Multiplexing (SDM) is being studied. Spatial multiplex transmission systems using multi-core fibers can be applied to long-distance transmission lines on the seabed and land, shorter access / metro areas, data centers where transmission capacity is increasing significantly, and equipment. It is required to provide a multi-core fiber that has a wide variety of optical interconnects and has optical characteristics required for each.

  One of the important optical characteristics in multi-core fibers is transmission loss. For measuring the transmission loss, a wavelength loss characteristic measurement method using an OTDR (Optical Time Domain Reflectometer) or a monochromator is usually used. OTDR is one of the most basic optical fiber measuring devices that can capture the change in loss characteristics in the length of an optical fiber. By using the OTDR, it is possible to grasp the homogeneity in the longitudinal direction of the optical fiber, and when an abnormal point exists, it is possible to cope with it by identifying and excising the part.

Paul Mitchell et al., 57 Channel (19x3) Spatial Multiplexer Fabricated using Direct Laser Inscription, OFC2014, M3K.5.

  A multi-core fiber has a plurality of core parts, but each core part is required to have a desired optical characteristic, and thus the optical characteristics of each core part need to be individually measured. Since each core part is two-dimensionally arranged in the cladding part, in order to measure the optical characteristics of each core part, it is necessary to input and output test light to each core part individually. As a method for inputting / outputting light to / from each of the two-dimensionally arranged core parts, using a aligner, a single-core optical fiber core part for inputting / outputting light and a multi-core fiber core part There is a method of aligning the axes. However, this method is inefficient from the viewpoint of the measurement man-hour at the time of manufacture because it takes a lot of time to align each core part.

  Multi-core fan-out (sometimes called multi-core fan-in) is being studied as an optical input / output device for multi-core fibers. The multi-core fan-out is a component formed by bundling a plurality of optical fibers so that at one end, the core portions are arranged in the same arrangement as the core portions of the multi-core fiber. By using multi-core fan-out, alignment efficiency for each core can be greatly improved. However, even when the multi-core fanout is used, it is necessary to perform measurement by connecting an OTDR to each of the plurality of core units. In this case, since it takes time to average the measurement data in the OTDR measurement, there is a problem that the measurement time increases as the number of core parts to be measured increases.

  The present invention has been made in view of the above, and is a measurement component for an optical fiber transmission body that can efficiently measure the optical characteristics of each core section of an optical fiber transmission body having a plurality of core sections in a shorter time. And it aims at providing the measuring method of an optical fiber transmission body.

  In order to solve the above-described problems and achieve the object, a measurement component of an optical fiber transmission body according to one aspect of the present invention includes a plurality of core portions, and includes a first end portion and a second end portion. A measuring component for inputting test light to a fiber transmission body, the first component having an optical input waveguide core portion connected to the first end portion and connected to the first core portion of the plurality of core portions. A second part having a first connection waveguide core part connected to the component and to the second end part, and connecting the first core part and the second core part among the plurality of core parts at the second end part. And a component.

  In the measurement component of the optical fiber transmission body according to one aspect of the present invention, the number of the plurality of core portions included in the optical fiber transmission body is N (N is an integer of 3 or more), and the second component is The second end portion includes an n-th connected waveguide core portion that connects the n-th core portion (n is an integer from 1 to N-2) and the (n + 1) -th core portion among the plurality of core portions. The first component has a (n + 1) -th connected waveguide core portion that connects the (n + 1) -th core portion and the (n + 2) -th core portion among the plurality of core portions at the first end portion. Features.

  The measurement component of the optical fiber transmission body according to one aspect of the present invention includes: the first connection waveguide core portion, the nth connection waveguide core portion, or the (n + 1) th connection waveguide core portion having two conductors. The waveguide core portion is configured to be connected via an optical connector.

  The measurement component of the optical fiber transmission body according to one aspect of the present invention includes: the first connection waveguide core portion, the nth connection waveguide core portion, or the (n + 1) th connection waveguide core portion having two conductors. The waveguide core portion is formed by fusion splicing.

  The measurement component of the optical fiber transmission body according to one aspect of the present invention is configured such that the first connection waveguide core part, the nth connection waveguide core part, or the (n + 1) th connection waveguide core part is the first connection waveguide core part. It is formed inside an optical component constituting the component or the second component.

  An optical fiber transmission body measurement component according to an aspect of the present invention is a measurement component that includes a plurality of core portions and inputs test light to an optical fiber transmission body having a first end and a second end. When the number of the plurality of core parts included in the optical fiber transmission body is N (N is an integer of 2 or more), the first core part is connected to the first end part, and the first core part is connected to the first core part. An optical input waveguide core part for inputting light, and an input side connected to the (n + 1) th core part (n is an integer from 1 to N-1) among the plurality of core parts at the first end part ( n + 1) a first component having a connection waveguide core portion, and an output-side n-th connection waveguide connected to the second end portion and connected to the n-th core portion of the plurality of core portions at the second end portion. A second component having a core portion, and the output side n-th connected waveguide core portion and the input side first portion n + 1), characterized in that the connecting waveguide core portion are connected.

  In the measurement component of the optical fiber transmitter according to one aspect of the present invention, the output-side n-th connected waveguide core portion and the input-side (n + 1) -th connected waveguide core portion are connected via an optical connector. It is characterized by.

  In the measurement component of the optical fiber transmitter according to one aspect of the present invention, the output-side n-th connected waveguide core portion and the input-side (n + 1) -th connected waveguide core portion are fusion-connected. It is characterized by.

  In the measurement component of the optical fiber transmission body according to one aspect of the present invention, the mode field diameters of the plurality of core portions included in the optical fiber transmission body and the mode field diameters of the respective waveguide core portions are different from each other. It is characterized by.

  An optical fiber transmission body measurement component according to an aspect of the present invention includes an interval between a plurality of core portions of the optical fiber transmission body and an interval between a plurality of waveguide core portions on a connection end surface of the first component. Unlike the above, the interval between the plurality of core portions of the optical fiber transmission body and the interval between the plurality of waveguide core portions on the connection end face of the second component are different, and the waveguide core portion of the first component Only a part of the plurality of waveguide core parts are connected so that a connection loss with the core part of the optical fiber transmission body is a predetermined value or less, and part of the waveguide core part of the second component Only the plurality of waveguide core portions are connected so that the connection loss with the core portion of the optical fiber transmission body is a predetermined value or less.

  An optical fiber transmission body measurement component according to an aspect of the present invention is connected between the optical fiber transmission body and the first component, and includes a plurality of core portions of the optical fiber transmission body and the first component. A first intermediate part having a plurality of intermediate connection waveguide core parts respectively connecting a plurality of waveguide core parts; and connected between the optical fiber transmission body and the second part; A second intermediate part having a plurality of intermediate connection waveguide core parts respectively connecting a plurality of core parts and a plurality of waveguide core parts of the second part, and the plurality of core parts of the optical fiber transmission body And the interval between the plurality of waveguide core portions on the connection end surface of the first component are different, and the interval between the plurality of core portions of the optical fiber transmission body and the connection end surface of the second component are different. Different spacing between multiple waveguide cores The intervals between the plurality of intermediate connection waveguide core portions in the first intermediate component are the intervals between the plurality of core portions of the optical fiber transmission body and the plurality of waveguide cores on the connection end surface of the first component. The distance between the plurality of intermediate connection waveguide core portions in the second intermediate component is the distance between the plurality of core portions of the optical fiber transmission body and the first interval. It is a value between the intervals between the plurality of waveguide core portions on the connection end face of the two parts.

  An optical fiber transmission body measurement method according to an aspect of the present invention is an optical fiber transmission body measurement method using a measurement component of an optical fiber transmission body according to an aspect of the present invention. Test light is input from the input waveguide core to the first core of the optical fiber transmitter, and backscattered light from each core of the optical fiber transmitter is measured.

  In the method for measuring an optical fiber transmitter according to an aspect of the present invention, the OTDR is a coherent OTDR.

  According to the present invention, since the plurality of core portions of the optical fiber transmission body are connected in series via the waveguide core portion, the optical characteristics of each core portion can be efficiently measured in a shorter time. .

FIG. 1 is a schematic diagram illustrating a state in which a measurement component according to Embodiment 1 is connected to a multicore fiber. FIG. 2 is a diagram for explaining the connection state of the core portion and the measurement method when the measurement component according to the first embodiment is used. FIG. 3 is a diagram for explaining the connection state of the core portion and the measurement method when the measurement component according to the second embodiment is used. FIG. 4 is a diagram for explaining the connection state of the core part and the measurement method when the measurement component according to the third embodiment is used. FIG. 5 is a diagram for explaining the connection state of the core portion and the measurement method when the measurement component according to the fourth embodiment is used. FIG. 6 is a diagram for explaining the connection state of the core portion and the measurement method when the measurement component according to the fifth embodiment is used. FIG. 7 is a diagram for explaining the measurement dynamic range of OTDR. FIG. 8 is a diagram for explaining a measurement method using the measurement component and the coherent OTDR according to the first embodiment. FIG. 9 is a diagram for explaining the connection state of the core part and the measurement method when the measurement component according to the sixth embodiment is used. FIG. 10 is a diagram for explaining the positional relationship between the connection waveguide core portion of the measurement component according to Embodiment 6 and the core portion of the multicore fiber at the time of connection. FIG. 11 is a diagram for explaining the connection state of the core portion and the measurement method when the measurement component according to the seventh embodiment is used. FIG. 12 is a diagram for explaining the positional relationship between the connection waveguide core portion of the measurement component according to the seventh embodiment and the core portion of the multicore fiber at the time of connection.

  DESCRIPTION OF EMBODIMENTS Embodiments of an optical fiber transmission body measurement part and an optical fiber transmission body measurement method according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments. Moreover, in each drawing, the same code | symbol is attached | subjected suitably to the same or corresponding element. Furthermore, it should be noted that the drawings are schematic, and dimensional relationships between elements may differ from actual ones. Even between the drawings, there are cases in which portions having different dimensional relationships and ratios are included.

(Embodiment 1)
FIG. 1 is a schematic diagram illustrating a state in which a measurement component according to Embodiment 1 is connected to a multicore fiber.

  The multi-core fiber 10 includes seven core parts, a first core part 11, a second core part 12, a third core part 13, a fourth core part 14, a fifth core part 15, a sixth core part 16, and a seventh core part. The core part 17 and the clad part 18 which is formed in the outer periphery of these core parts and whose refractive index is lower than each core part are provided. The 1st core part 11-the 7th core part 17 are arrange | positioned so that the 2nd core part 12-the 7th core part 17 may form a regular hexagon centering on the 1st core part 11 in the cross section perpendicular | vertical to a longitudinal direction. ing. That is, as for the 1st core part 11-the 7th core part 17, the space | interval between adjacent core parts is all equal, and it is substantially constant in a longitudinal direction. Moreover, the multi-core fiber 10 has the 1st end part 10a and the 2nd end part 10b located in the other side of the 1st end part 10a in a longitudinal direction.

The measurement component 100 includes a first component 110 and a second component 120.
The first component 110 includes a first optical fiber 110a, a second optical fiber 110b, a third optical fiber 110c, a fourth optical fiber 110d, a fifth optical fiber 110e, a sixth optical fiber 110f, and a seventh optical fiber 110g. These optical fibers have a multi-core fan-out structure in which glass fibers 110h are bundled. The end portions of these optical fibers are bundled by a glass capillary 110 h so that the core portions of these optical fibers are arranged corresponding to the arrangement of the first core portion 11 to the seventh core portion 17 of the multicore fiber 10. Yes. In order to realize this, the first optical fiber 110a to the seventh optical fiber 110g have the same clad diameter as the distance between adjacent core portions in the multi-core fiber 10, and are bundled in a hexagonal close-packed manner. ing. Further, the first optical fiber 110a to the seventh optical fiber 110g may be formed of a small diameter fiber whose cladding diameter is smaller than a normal optical fiber (125 μm). Further, at the end opposite to the side bundled by the glass capillary 110h, the second optical fiber 110b and the third optical fiber 110c, the fourth optical fiber 110d and the fifth optical fiber 110e, the sixth optical fiber 110f and the first optical fiber 110f The seven optical fibers 110g are connected by an optical connector 100a.

  The second component 120 includes a first optical fiber 120a, a second optical fiber 120b, a third optical fiber 120c, a fourth optical fiber 120d, a fifth optical fiber 120e, a sixth optical fiber 120f, and a seventh optical fiber 120g. These optical fibers have a multi-core fanout structure in which glass capillaries 120h are bundled. The end portions of these optical fibers are bundled by a glass capillary 120 h so that the core portions of these optical fibers are arranged corresponding to the arrangement of the first core portion 11 to the seventh core portion 17 of the multicore fiber 10. Yes. In order to realize this, the clad diameters of the first optical fiber 120a to the seventh optical fiber 120g are the same as the distance between adjacent core portions in the multi-core fiber 10, and are bundled in a hexagonal close-packed manner. Yes. Further, the first optical fiber 120a to the seventh optical fiber 120g may be constituted by a small diameter fiber whose cladding diameter is smaller than a normal optical fiber (125 μm). Further, at the end opposite to the side bundled by the glass capillary 120h, the first optical fiber 120a and the second optical fiber 120b, the third optical fiber 120c and the fourth optical fiber 120d, the fifth optical fiber 120e and the first optical fiber The six optical fibers 120f are connected by an optical connector 100a.

  The first component 110 is connected to the first end 10a of the multi-core fiber 10, and the second component 120 is connected to the second end 10b. Here, in order to facilitate the connection, connecting capillaries 130 and 140 having substantially the same outer diameter as the glass capillaries 110h and 120h are provided on the first end portion 10a side and the second end portion 10b side of the multicore fiber 10, respectively. Provided. When connecting the first component 110 to the multi-core fiber 10, the first core portion 11 to the seventh core portion 17 of the multi-core fiber 10 and the core portions of the first optical fiber 110 a to the seventh optical fiber 110 g are respectively connected later. As shown in the drawing, the multi-core fiber 10 and the first component 110 are adjusted and aligned in the orthogonal direction and the direction around the axis so as to be connected in the combination described in detail. Similarly, when connecting the second component 120 to the multicore fiber 10, the first core portion 11 to the seventh core portion 17 of the multicore fiber 10 and the core portions of the first optical fiber 120a to the seventh optical fiber 120g, Are aligned and connected by adjusting the multi-core fiber 10 and the second component 120 in the orthogonal direction and the direction around the axis as indicated by arrows in the drawing. In addition, it connects in the state which the end surfaces of the core part connected contact | abut at the time of connection. At this time, matching oil or the like may be interposed between the end of the multi-core fiber 10 and the end of each optical fiber. Further, the first core portion 11 to the seventh core portion 17 of the multicore fiber 10 and the core portions of the first optical fiber 120a to the seventh optical fiber 120g may be optically connected to each other. Alternatively, a spatial optical coupling system may be provided between each of the second components 120 and the multi-core fiber 10 to optically connect the corresponding core portions.

FIG. 2 is a diagram for explaining the connection state of the core portion and the measurement method when the measurement component according to the first embodiment is used. In FIG. 2 (a), the arrangement of the core portions of the optical fibers included in the multi-core fiber 10, the first component 110, and the second component 120 is shown in a flat form for simplification of the drawing. . In FIG. 2A, only the core portion is illustrated for the optical fibers provided in the first component 110 and the second component 120, and the description of the cladding portion is omitted. The same applies to the drawings described later.
In FIG. 2A, a core part included in the first optical fiber 110 a of the first component 110 is referred to as an optical input waveguide core part 111.

  Further, in the second component 120, the core part formed by connecting the core part of the first optical fiber 120a and the core part of the second optical fiber 120b with the optical connector 100a is referred to as the first connection waveguide core part 101. To do. The core part formed by connecting the core part of the third optical fiber 120 c and the core part of the fourth optical fiber 120 d by the optical connector 100 a is referred to as a third connection waveguide core part 103. The core part formed by connecting the core part included in the fifth optical fiber 120e and the core part included in the sixth optical fiber 120f with the optical connector 100a is referred to as a fifth connection waveguide core part 105. The core part included in the seventh optical fiber 120 g is the waveguide core part 112.

  Similarly, in the first component 110, the core part formed by connecting the core part included in the second optical fiber 110b and the core part included in the third optical fiber 110c with the optical connector 100a is used as the second connection waveguide core part 102. And A core part formed by connecting the core part of the fourth optical fiber 110d and the core part of the fifth optical fiber 110e with the optical connector 100a is referred to as a fourth connection waveguide core part 104. A core part formed by connecting the core part included in the sixth optical fiber 110f and the core part included in the seventh optical fiber 110g with the optical connector 100a is referred to as a sixth connection waveguide core part 106.

  As shown in FIG. 2A, the optical input waveguide core portion 111 is connected to the first core portion 11 of the multicore fiber 10. In the second component 120, the first connection waveguide core portion 101 connects the first core portion 11 and the second core portion 12 at the second end portion 10 b of the multicore fiber 10. The third connection waveguide core portion 103 connects the third core portion 13 and the fourth core portion 14 at the second end portion 10b. The fifth connection waveguide core unit 105 connects the fifth core unit 15 and the sixth core unit 16 at the second end 10b.

  In the first component 110, the second connection waveguide core portion 102 connects the second core portion 12 and the third core portion 13 at the first end portion 10 a of the multicore fiber 10. The fourth connection waveguide core unit 104 connects the fourth core unit 14 and the fifth core unit 15 at the first end 10a. The sixth connection waveguide core unit 106 connects the sixth core unit 16 and the seventh core unit 17 at the first end 10a.

  Accordingly, the first core portion 11 to the seventh core portion 17 of the multicore fiber 10 are connected in series via the first connection waveguide core portion 101 to the sixth connection waveguide core portion 106. Therefore, as shown in FIG. 2A, when test light that is pulsed light is input from the OTDRO to the optical input waveguide core part 111, the test light is transmitted from the first core part 11 to the seventh core part 17 of the multicore fiber 10. Will be propagated. Therefore, backscattered light from all the core parts of the multi-core fiber 10 can be observed in one measurement, and an OTDR measurement waveform can be obtained. Thereby, the measurement time is significantly shortened compared with the case where measurement is performed for each core part, and efficient measurement can be performed in a short time.

  Here, FIG. 2B is a diagram schematically showing the measurement waveform. In FIG. 2B, the peak waveform seen in the measurement waveform is generated at the connection point of the core portion by the optical connectors 100a and 100a and the connection point between the first component 110 and the second component 120 and the multi-core fiber 10. Due to Fresnel reflection or splice loss. Therefore, the position of the measurement waveform indicating each core portion of the multi-core fiber 10 can be specified by the position of these peak waveforms. Specifically, the measurement waveforms in the regions 11S, 12S, 13S, 14S, 15S, 16S, and 17S in FIG. 2B are respectively the first core unit 11, the second core unit 12, the third core unit 13, It is a measurement waveform corresponding to the 4-core part 14, the fifth core part 15, the sixth core part 16, and the seventh core part 17.

(Embodiment 2)
FIG. 3 is a diagram for explaining the connection state of the core portion and the measurement method when the measurement component according to the second embodiment is used. The measurement component 100A according to the second embodiment includes a first component 110A and a second component 120A.

  The second component 120A is different from the second component 120 in the following points. That is, the first connecting waveguide core portion 101A is configured by fusion-connecting the core portion of the first optical fiber 120a and the core portion of the second optical fiber 120b. The core portion of the third optical fiber 120c and the core portion of the fourth optical fiber 120d are fusion-spliced to form a third connection waveguide core portion 103A. The core portion included in the fifth optical fiber 120e and the core portion included in the sixth optical fiber 120f are fusion-bonded to form a fifth connection waveguide core portion 105A.

  Similarly, the first component 110A is different from the first component 110 in the following points. That is, the core portion of the second optical fiber 110b and the core portion of the third optical fiber 110c are fusion-bonded to form the second connection waveguide core portion 102A. The core portion of the fourth optical fiber 110d and the core portion of the fifth optical fiber 110e are fusion-bonded to form a fourth connection waveguide core portion 104A. The core portion of the sixth optical fiber 110f and the core portion of the seventh optical fiber 110g are fusion-spliced to form a sixth connection waveguide core portion 106A.

  Accordingly, the first core portion 11 to the seventh core portion 17 of the multicore fiber 10 are connected in series via the first connection waveguide core portion 101A to the sixth connection waveguide core portion 106A. Therefore, as shown in FIG. 3A, when test light that is pulsed light is input from the OTDRO to the optical input waveguide core portion 111 of the first component 110 </ b> A, the test light is transmitted from the first core portions 11 to 11 of the multicore fiber 10. All of the seventh core portion 17 is propagated. Therefore, backscattered light from all the core parts of the multicore fiber 10 can be observed by one measurement, and a measurement waveform can be obtained. Thereby, the measurement time is significantly shortened compared with the case where measurement is performed for each core part, and efficient measurement can be performed in a short time.

  Here, FIG. 3B schematically shows the measurement waveform. In FIG. 3B, the peak waveform seen in the measurement waveform is due to Fresnel reflection or connection loss that occurs at the connection point between each of the first component 110 </ b> A and the second component 120 </ b> A and the multicore fiber 10. Therefore, the position of the measurement waveform indicating each core portion of the multi-core fiber 10 can be specified by the position of these peak waveforms.

(Embodiment 3)
FIG. 4 is a diagram for explaining the connection state of the core part and the measurement method when the measurement component according to the third embodiment is used. The measurement component 100B according to the third embodiment includes a first component 110B and a second component 120B.

  The second component 120B is different from the second component 120A in the following points. That is, the mode field diameter (MFD) of the first optical fiber 120 a to the seventh optical fiber 120 g is smaller than the MFD of the first core portion 11 to the seventh core portion 17 of the multicore fiber 10. And the core part which the 1st optical fiber 120a has, and the core part which the 2nd optical fiber 120b has are fusion-spliced, and the 1st connection waveguide core part 101B is comprised. A third connection waveguide core 103B is configured by fusion-bonding the core of the third optical fiber 120c and the core of the fourth optical fiber 120d. A core portion included in the fifth optical fiber 120e and a core portion included in the sixth optical fiber 120f are fusion-bonded to form a fifth connection waveguide core portion 105B. A core part included in the seventh optical fiber 120g of the second component 120B is referred to as a waveguide core part 112B.

  Similarly, the first component 110B is different from the first component 110 in the following points. That is, the MFDs of the first optical fiber 110 a to the seventh optical fiber 110 g are made smaller than the MFDs of the first core part 11 to the seventh core part 17 of the multicore fiber 10. And the core part which the 2nd optical fiber 110b has, and the core part which the 3rd optical fiber 110c has are fusion-spliced, and the 2nd connection waveguide core part 102B is comprised. The core portion included in the fourth optical fiber 110d and the core portion included in the fifth optical fiber 110e are fusion-spliced to form a fourth connection waveguide core portion 104B. The core portion of the sixth optical fiber 110f and the core portion of the seventh optical fiber 110g are fusion-spliced to form a sixth connection waveguide core portion 106B. A core part included in the first optical fiber 110a of the first component 110B is referred to as an optical input waveguide core part 111B.

  Accordingly, the first core portion 11 to the seventh core portion 17 of the multicore fiber 10 are connected in series via the first connection waveguide core portion 101B to the sixth connection waveguide core portion 106B. Therefore, as shown in FIG. 4A, when test light that is pulsed light is input from the OTDRO to the optical input waveguide core part 111B of the first component 110B, the test light is transmitted from the first core parts 11 to 11 of the multicore fiber 10. All of the seventh core portion 17 is propagated. Thereby, the measurement time is significantly shortened compared with the case where measurement is performed for each core part, and efficient measurement can be performed in a short time.

  Here, FIG. 4B is a diagram schematically showing the measurement waveform. As described above, the MFDs of the optical input waveguide core part 111B, the first connection waveguide core part 101B to the sixth connection waveguide core part 106B, and the waveguide core part 112B are the first core parts 11 to 11 of the multicore fiber 10. It is smaller than the MFD of the seventh core portion 17. Therefore, a connection loss occurs at the connection point between the core portions having different MFDs. Here, when test light is input from a core portion having a large MFD to a waveguide core portion having a small MFD, it appears that the optical power has once increased. Conversely, when test light is input from a waveguide core portion with a small MFD to a core portion with a large MFD, it appears that the optical power has decreased. For this reason, as shown in FIG. 4B, a peak waveform extending vertically is seen in the measured waveform. Therefore, the position of the measurement waveform indicating each core portion of the multi-core fiber 10 can be specified by the position of these peak waveforms.

  In the third embodiment, the MFDs of the optical input waveguide core portion 111B, the first connection waveguide core portion 101B to the sixth connection waveguide core portion 106B, and the waveguide core portion 112B are the first of the multicore fiber 10. Although it is smaller than the MFD of the core portion 11 to the seventh core portion 17, it may be larger than the MFD of the first core portion 11 to the seventh core portion 17 of the multicore fiber 10.

(Embodiment 4)
FIG. 5 is a diagram for explaining the connection state of the core portion and the measurement method when the measurement component according to the fourth embodiment is used. The measurement component 100C according to the fourth embodiment includes a first component 110C and a second component 120C.

  The first component 110C is different from the first component 110 in the following points. That is, the first component 110C includes an input-side second connection waveguide core portion 112C configured by a core portion included in the second optical fiber 110b, and an input-side third input configured by a core portion included in the third optical fiber 110c. The input-side fifth connecting waveguide core portion 114C configured by the connecting waveguide core portion 113C, the input-side fourth connecting waveguide core portion 114C configured by the core portion included in the fourth optical fiber 110d, and the core portion included in the fifth optical fiber 110e. The input-side sixth connected waveguide core 116C configured by the connecting waveguide core 115C, the core included in the sixth optical fiber 110f, and the input-side seventh configured by the core included in the seventh optical fiber 110g. And a connecting waveguide core portion 117C.

  The second component 120C is different from the second component 120 in the following points. That is, the second component 120C includes an output-side first connection waveguide core part 121C configured by a core part included in the first optical fiber 120a and an output-side second output configured by a core part included in the second optical fiber 120b. The output-side third connecting waveguide core portion 123C configured by the connecting waveguide core portion 122C, the core portion included in the third optical fiber 120c, and the output-side fourth output configured by the core portion included in the fourth optical fiber 120d. The output side sixth connecting waveguide core portion 125C configured by the connecting waveguide core portion 124C, the core portion included in the fifth optical fiber 120e, and the output side sixth configured by the core portion included in the sixth optical fiber 120f. And a connecting waveguide core portion 126C.

  In the first component 110 </ b> C, the input-side second connection waveguide core portion 112 </ b> C is connected to the second core portion 12 at the first end portion 10 a of the multicore fiber 10. The input-side third connection waveguide core portion 113C is connected to the third core portion 13 at the first end portion 10a. The input-side fourth connection waveguide core portion 114C is connected to the fourth core portion 14 at the first end portion 10a. The input-side fifth connection waveguide core portion 115C is connected to the fifth core portion 15 at the first end portion 10a. The input-side sixth connection waveguide core portion 116C is connected to the sixth core portion 16 at the first end portion 10a. The input-side seventh connection waveguide core portion 117C is connected to the seventh core portion 17 at the first end portion 10a.

  In the second component 120 </ b> C, the output-side first connection waveguide core portion 121 </ b> C is connected to the first core portion 11 at the second end portion 10 b of the multicore fiber 10. The output-side second connection waveguide core portion 122C is connected to the second core portion 12 at the second end portion 10b. The output-side third connection waveguide core portion 123C is connected to the third core portion 13 at the second end portion 10b. The output-side fourth connection waveguide core portion 124C is connected to the fourth core portion 14 at the second end portion 10b. The output-side fifth connection waveguide core portion 125C is connected to the fifth core portion 15 at the second end portion 10b. The output-side sixth connection waveguide core portion 126 </ b> C is connected to the sixth core portion 16 at the second end portion 10 b of the multicore fiber 10.

  In the measurement component 100C, the output-side first connection waveguide core portion 121C and the input-side second connection waveguide core portion 112C are connected via the optical connector 100a. The output-side second connection waveguide core portion 122C and the input-side third connection waveguide core portion 113C are connected via the optical connector 100a. The output-side third connection waveguide core portion 123C and the input-side fourth connection waveguide core portion 114C are connected via the optical connector 100a. The output-side fourth connection waveguide core portion 124C and the input-side fifth connection waveguide core portion 115C are connected via the optical connector 100a. The output-side fifth connection waveguide core portion 125C and the input-side sixth connection waveguide core portion 116C are connected via the optical connector 100a. The output-side sixth connection waveguide core portion 126C and the input-side seventh connection waveguide core portion 117C are connected via the optical connector 100a.

  Thereby, the 1st core part 11-the 7th core part 17 of multi-core fiber 10 are connected in series via each output side connection waveguide core part and each input side connection waveguide core part. Therefore, as shown in FIG. 5A, when test light that is pulsed light is input from the OTDRO to the optical input waveguide core part 111, the test light is transmitted from the first core part 11 to the seventh core part 17 of the multicore fiber 10. Will be propagated. Therefore, backscattered light from all the core parts of the multicore fiber 10 can be observed by one measurement, and a measurement waveform can be obtained. Thereby, the measurement time is significantly shortened compared with the case where measurement is performed for each core part, and efficient measurement can be performed in a short time.

  In particular, according to the measurement component 100 </ b> C according to the fourth embodiment, the test light is transmitted from the first end portion 10 a to the second end in any of the first core portion 11 to the seventh core portion 17 of the multicore fiber 10. It will propagate toward the part 10b. Accordingly, as shown in FIG. 5B, in the measurement waveform, in the regions 11S to 17S corresponding to the first core portion 11 to the seventh core portion 17, the measurement waveform is also from the first end portion 10a side to the second end portion. It becomes lined up in the direction to 10b. In this case, for example, when there is an abnormal point in the multicore fiber at a predetermined distance from the first end 10a, the abnormal point is positioned at a predetermined distance from each first end 10a on the measurement waveform of each region. The waveform shown will appear, and it will be easier to identify abnormal points.

  The measurement component 100C is preferably used when the first end portion 10a and the second end portion 10b are relatively close to each other, for example, when the multi-core fiber 10 is in a bobbin-wound state. it can. Therefore, for example, the effect is exhibited when the multi-core fiber 10 is measured before shipment from the factory.

(Embodiment 5)
FIG. 6 is a diagram for explaining the connection state of the core portion and the measurement method when the measurement component according to the fifth embodiment is used. The measurement component 100D according to the fifth embodiment includes a first component 110D and a second component 120D.

  The first component 110 </ b> D constitutes the first component 110 </ b> D and includes the following waveguide core portion formed inside an optical component made of an optical member such as quartz glass. That is, the optical input waveguide core portion 111D, the second connection waveguide core portion 102D, the fourth connection waveguide core portion 104D, and the sixth connection waveguide core portion 106D.

  Similarly, the second component 120D includes the following waveguide core portion that is included in an optical component that is included in an optical member such as quartz glass and that constitutes the second component 120D. That is, the first connection waveguide core portion 101D, the third connection waveguide core portion 103D, the fifth connection waveguide core portion 105D, and the waveguide core portion 112D.

  These waveguide core portions are formed in the optical component by, for example, laser drawing (see Non-Patent Document 1, for example).

  Here, as shown in FIG. 6, the optical input waveguide core portion 111 </ b> D is connected to the first core portion 11 of the multicore fiber 10. In the second component 120 </ b> D, the first connection waveguide core portion 101 </ b> D connects the first core portion 11 and the second core portion 12 at the second end portion 10 b of the multicore fiber 10. The third connection waveguide core portion 103D connects the third core portion 13 and the fourth core portion 14 at the second end portion 10b. The fifth connection waveguide core portion 105D connects the fifth core portion 15 and the sixth core portion 16 at the second end portion 10b.

  In the first component 110 </ b> D, the second connection waveguide core portion 102 </ b> D connects the second core portion 12 and the third core portion 13 at the first end portion 10 a of the multicore fiber 10. The fourth connection waveguide core portion 104D connects the fourth core portion 14 and the fifth core portion 15 at the first end portion 10a. The sixth connection waveguide core portion 106D connects the sixth core portion 16 and the seventh core portion 17 at the first end portion 10a.

  Accordingly, the first core portion 11 to the seventh core portion 17 of the multicore fiber 10 are connected in series via the first connection waveguide core portion 101D to the sixth connection waveguide core portion 106D. Therefore, as shown in FIG. 6, when test light that is pulsed light is input from the OTDRO to the optical input waveguide core part 111D via the optical fiber F, all core parts of the multicore fiber 10 are measured in one measurement. A waveform will be obtained. Thereby, the measurement time is significantly shortened compared with the case where measurement is performed for each core part, and efficient measurement can be performed in a short time. Thus, the measurement component according to the present invention is not limited to the multi-core fan-out structure.

  By the way, according to the said embodiment, since it measures by connecting a several core part, the total measurement distance becomes the distance which multiplied the length of the multi-core fiber 10 by the number of core parts. Here, the measurement dynamic range of the commercially available OTDR is about 50 dB at the maximum, but if the transmission loss of the multi-core fiber 10 is assumed to be about 0.2 dB / km, limit measurement is possible when the number of core parts is seven. The length is about 35 km (50 / 0.2 / 7≈35).

  FIG. 7 is a diagram for explaining the measurement dynamic range of OTDR. In a region where the measurement distance has increased and the loss level has fallen beyond the measurement dynamic range as shown by the diagonal lines, even if the measurement waveform is actually shown as a broken line, a constant loss is shown as shown by the solid line. Measured as a level. Therefore, in order to apply the present invention to a longer multi-core fiber, a multi-core fiber having a large number of core parts, or a multi-core fiber having a large transmission loss, it is necessary to expand the dynamic range.

  FIG. 8 is a diagram for explaining a measurement method using the measurement component and the coherent OTDR (C-OTDR) according to the first embodiment. In the measurement system shown in FIG. 8, in the configuration shown in FIG. 2, OTDRO is replaced with coherent OTDRCO, and an optical amplifier 100b is inserted into each optical connector 100a. As described above, if a C-OTDR that can be used in combination with an optical amplifier is used, the intensity level of the test light is amplified by the optical amplifier 100b that is appropriately arranged, and the loss is compensated, a long multi-core fiber or core portion can be obtained. A large number of multi-core fibers or a multi-core fiber having a large transmission loss can be suitably measured.

  In the first to fourth embodiments, one end of the seventh optical fiber 120g of the second component 120 is connected to the multicore fiber 10 and the other end is released. At this time, the test light is Fresnel-reflected at the end face of the released end of the seventh optical fiber 120g, and as a result, a peak waveform appears at a position where no connection point or connection loss exists in the OTDR measurement waveform. There is a case. Such a peak waveform may cause misidentification of the position of the connection point. Therefore, it is preferable to apply an antireflection treatment to the released end of the seventh optical fiber 120g. As a method of non-reflective treatment, the end is immersed in matching oil, the end surface is cut so as to be inclined with respect to the central axis of the core, or an oblique polishing connector (APC connector) is provided at the end. There is a way. Further, in the configuration in which the optical fibers of the measurement component 100 are connected via the optical connector 100a as in the first and fourth embodiments, the peak that causes Fresnel reflection in the optical connector 100a to misidentify the position of the connection point. A waveform may be generated. In such a case, it is preferable to use an APC connector as the optical connector 100a. Further, when the MFD of the optical fiber of the measurement component 100B is made smaller than the MFD of the core portion of the multicore fiber 10 as in the third embodiment, the embodiment is used to connect the optical fibers of the measurement component 100B. Although a connector may be used similarly to 1, it is preferable to use an APC connector at this time.

(Embodiment 6)
FIG. 9 is a diagram for explaining the connection state of the core part and the measurement method when the measurement component according to the sixth embodiment is used. A measurement component 100E according to the sixth embodiment includes the first component 110 and the second component 120 of the first embodiment, and further includes a first intermediate component 150 and a second intermediate component 160.

As shown in FIG. 9 (a), the multi-core fiber 10A to be measured includes seven core parts, a first core part 11A, a second core part 12A, a third core part 13A, a fourth core part 14A, and a fifth core part. The core portion 15A, the sixth core portion 16A, and the seventh core portion 17A, and a clad portion that is formed on the outer periphery of these core portions and has a lower refractive index than each core portion. The first core portion 11A to the seventh core portion 17A are arranged so that the second core portion 12A to the seventh core portion 17A form a regular hexagon around the first core portion 11A in the cross section perpendicular to the longitudinal direction. ing. That is, in the first core portion 11A to the seventh core portion 17A, the intervals P3 between the adjacent core portions are all equal and substantially constant in the longitudinal direction. The interval P3 is smaller than the interval between adjacent core portions in the first core portion 11 to the seventh core portion 17 of the multicore fiber 10 shown in FIG.
In FIG. 9A, the arrangement of the core portions of the optical fibers included in the multi-core fiber 10A, the first component 110, and the second component 120 is shown in a flat form for simplification of the drawing. . Therefore, the interval P3 and the intervals P1 and P2 described later are illustrated differently from the actual one. This point will be described in detail later.

  On the other hand, in the 1st component 110 and the 2nd component 120, the space | interval between the connection waveguide core parts contained in each in a connection end surface is adjacent in the 1st core part 11 of the multi-core fiber 10, and the 7th core part 17. The intervals P1 and P2 are the same as the interval between the core portions to be performed. Therefore, the intervals P1 and P2 are larger than the interval P3.

  The first intermediate component 150 is connected to the first end portion 10Aa of the multicore fiber 10A between the multicore fiber 10A and the first component 110, and includes a plurality of core portions 11A to 17A of the multicore fiber 10A and a plurality of first components 110. A plurality of intermediate connection waveguide core portions 151, 152, 153, 154, 155, 156 for connecting the waveguide core portions (the optical input waveguide core portion 111 and the connection waveguide core portions 102, 104, 106) respectively. 157. The intermediate connection waveguide core portions 151 to 157 are arranged so that the intermediate connection waveguide core portions 152 to 157 form a regular hexagon around the intermediate connection waveguide core portion 151 in the cross section perpendicular to the longitudinal direction. .

  The second intermediate part 160 is connected to the second end 10Ab of the multicore fiber 10A between the multicore fiber 10A and the second part 120, and the plurality of core parts 11A to 17A of the multicore fiber 10A and the first part 120 are plural. A plurality of intermediate connection waveguide core portions 161, 162, 163, 164, 165, 166, 167 connecting the waveguide core portions (respective connection waveguide core portions 101, 103, 105 and waveguide core portion 112), respectively. Have The intermediate connection waveguide core portions 161 to 167 are arranged so that the intermediate connection waveguide core portions 162 to 167 form a regular hexagon around the intermediate connection waveguide core portion 161 in the cross section perpendicular to the longitudinal direction. . As in the case of the multi-core fiber 10A, for convenience of explanation, FIG. 9A illustrates the arrangement of the waveguide core portions in the first intermediate component 150 and the second intermediate component 160 in a flat shape. Yes. Therefore, the interval P4 and the interval P5, which will be described later, are illustrated so as to be different from actual ones.

  Here, the interval P4 between the plurality of intermediate connection waveguide core portions in the first intermediate component 150 is substantially constant in the longitudinal direction, and the interval P3 between the plurality of core portions of the multicore fiber 10A and the first component 110. It is a value between the space | interval P1 between several waveguide core part. Further, the interval P5 between the plurality of intermediate connection waveguide core portions in the second intermediate component 160 is substantially constant in the longitudinal direction, and the interval P between the plurality of core portions of the multicore fiber 10A and the plurality of second components. It is a value between the intervals P2 between the waveguide core portions. For example, the intervals P1 and P2 are 45 μm, the interval P3 is 40 μm, and the intervals P4 and P5 are 42 μm. FIG. 10 is a diagram for explaining the positional relationship between the connection waveguide core portion of the measurement component according to Embodiment 6 and the core portion of the multicore fiber at the time of connection. In the figure, the optical input waveguide core part 111, the second connection waveguide core part 102, the fourth connection waveguide core part 104, the sixth connection waveguide core part 106 of the first component 110, and the core part 11A of the multicore fiber 10A. 17A and intermediate connection waveguide core portions 151 to 157 of the first intermediate component 150 are shown. As shown in the drawing, each waveguide core part or core part has different intervals P1, P3, and P4, so that there is a positional shift between the corresponding waveguide core part and core part located on the outer peripheral side.

  When the first intermediate component 150 and the multi-core fiber 10A are directly connected and the second intermediate component 160 and the multi-core fiber 10A are directly connected, the connection loss increases due to the difference between the interval P3 and the intervals P1 and P2, and the measurement waveform becomes In some cases, the measurement dynamic range exceeds the OTDRO measurement dynamic range. On the other hand, by connecting the first intermediate part 150 and the second intermediate part 160 having an intermediate interval between them, the measurement waveform becomes the measurement dynamic of OTDRO as shown by the oblique lines in FIG. 9B. The value is not out of range, an accurate measurement waveform is obtained, and the measurable distance by OTDRO can be extended.

  The first intermediate component 150 and the second intermediate component 160 can be easily configured using a fan-out structure or a multi-core fiber. In the present embodiment, the intervals P1 and P2 are larger than the interval P3, but the intervals P1 and P2 may be smaller than the interval P3.

(Embodiment 7)
FIG. 11 is a diagram for explaining the connection state of the core portion and the measurement method when the measurement component according to the seventh embodiment is used. The measurement component 100F according to the seventh embodiment includes a first component 110F and a second component 120F. In the first component 110F shown in FIGS. 1 and 2, the fourth optical fiber 120d, the fifth optical fiber 110e, the sixth optical fiber 110f, and the seventh optical fiber 120g are not connected by the optical connector 100a. The configuration is as follows. These core portions are not shown in FIG. The core part included in the fourth optical fiber 120d is the waveguide core part 112F. In the second component 120E shown in FIGS. 1 and 2, the fourth optical fiber 120d, the fifth optical fiber 110e, the sixth optical fiber 110f, and the seventh optical fiber 120g are not connected by the optical connector 100a. The configuration is as follows. These core portions are not shown in FIG.

  The first component 110F is connected to the first end 10Aa of the multi-core fiber 10A shown in FIG. 9A, and the second component 120F is connected to the second end 10Ab of the multi-core fiber 10A.

  Here, similarly to the first component 110 and the second component 120 described above, in the first component 110F and the second component 120F, the interval between the connection waveguide core portions included in each of the first component 110F and the second component 120F is the interval on the connection end surface. P1 and P2. In the multi-core fiber 10A, the interval between adjacent core portions is the interval P3 different from the intervals P1 and P2.

FIG. 12 is a diagram for explaining the positional relationship in the plane perpendicular to the longitudinal direction between the connection waveguide core portion of the measurement component 110F and the core portion of the multicore fiber 10A at the time of connection, taking the first component 110F as an example. . As described above, the intervals P1 and P2 on the connection end surface between the connection waveguide core portions included in the first component 110F and the second component 120F are different from the interval P3 between the core portions included in the multicore fiber 10A. . In the seventh embodiment, as shown in FIG. 12, the central axes of the first component 110F and the multi-core fiber 10A are shifted, and some of the plurality of waveguide core portions (light input waveguides) of the waveguide core portions of the first component are used. Only the waveguide core portion 111, the second connection waveguide core portion 102, and the waveguide core portion 112F) are connected so that the connection loss with the core portions 11A, 12A, 13A, and 14A of the multi-core fiber 10A is less than a predetermined value. ing.
A circle indicated by a broken line is a position where the core portions of the fifth optical fiber 110e, the sixth optical fiber 110f, and the seventh optical fiber 120g exist. Also, for the second component 120F, the center axis of the second component 120F and the multi-core fiber 10A is shifted, and a plurality of waveguide core portions (the first connection waveguide core portion 101, the third connection core portion of the waveguide core portions). Only the connection waveguide core portion 103) is connected so that the connection loss with the core portions 11A, 12A, 13A, and 14A of the multi-core fiber 10A is not more than a predetermined value. Here, the predetermined value is appropriately set depending on the dynamic range of the OTDRO, the length of the multi-core fiber 1A, the transmission loss, and the like, and is, for example, 0.5 dB.

  Here, if the waveguide core portion at the center of the first component 110F and the second component 120F and the core portion at the center of the multi-core fiber 1A are connected in alignment, the connection is made due to the difference between the interval P3 and the intervals P1 and P2. Loss increases, and the measurement waveform may be in a range exceeding the OTDRO measurement dynamic range. On the other hand, if the connection is made as in the seventh embodiment, as in the case of FIG. 9B, the measurement waveform does not become a value outside the OTDRO measurement dynamic range, and an accurate measurement waveform is obtained. In addition, the measurable distance by OTDRO can be extended.

  In addition, in the structure shown to FIG. 11, 12, each core part 11A-14A of 1 A of multicore fibers can be measured. When measuring the other core parts 15A to 17A, each waveguide core part of the first component 110E is connected to the core parts 15A to 17A of the multicore fiber 10A so that the connection loss is equal to or less than a predetermined value. Can be done.

  In the above embodiment, the optical fiber transmission body as the measurement target is a multi-core fiber. However, the optical fiber transmission body as the measurement target only needs to include a plurality of core portions, for example, a plurality of optical fiber strands. May be an optical fiber ribbon that is arranged in parallel and collectively covered.

  Moreover, the number of the core parts with which the optical fiber transmission body as a measuring object is provided is not particularly limited. For example, in the measurement component according to the present invention, when the number of the plurality of core portions included in the optical fiber transmission body is N (N is an integer of 3 or more), the second component is the second end of the optical fiber transmission body. The n-th connected waveguide core portion connecting the n-th core portion (n is an integer from 1 to N-2) and the (n + 1) -th core portion among the plurality of core portions of the optical fiber transmission body The first component is an (n + 1) th connecting conductor that connects the (n + 1) th core part and the (n + 2) th core part among the plurality of core parts of the optical fiber transmission body at the first end of the optical fiber transmission body. It can comprise so that it may have a waveguide core part.

  In addition, for example, in the measurement component according to the present invention, when the number of the plurality of core portions included in the optical fiber transmission body is N (N is an integer equal to or greater than 2), the first component is the number of the optical fiber transmission body. An input side (n + 1) -connected waveguide core portion connected to the (n + 1) -th core portion (n is an integer from 1 to N-1) among the plurality of core portions of the optical fiber transmission body at one end portion The second component includes an output-side n-th connection waveguide core portion connected to the n-th core portion of the core portion of the optical fiber transmission body at the second end portion of the optical fiber transmission body, and the output-side n-th connection. The waveguide core part and the input side (n + 1) -th connected waveguide core part can be connected.

  Further, the present invention is not limited by the above embodiment. What was comprised combining each component mentioned above suitably is also contained in this invention. For example, in the fourth embodiment, the output side connection waveguide core part and the input side connection waveguide core part may be fusion-connected. Moreover, when using the measurement parts according to Embodiments 2 to 5, a C-OTDR and an optical amplifier may be used. Further effects and modifications can be easily derived by those skilled in the art. Therefore, the broader aspect of the present invention is not limited to the above-described embodiment, and various modifications can be made.

10, 10A Multi-core fiber 10a, 10Aa 1st end part 10b, 10Ab 2nd end part 11, 11A 1st core part 12, 12A 2nd core part 13, 13A 3rd core part 14, 14A 4th core part 15, 15A Fifth core part 16, 16A Sixth core part 17, 17A Seventh core part 18 Clad part 11S, 12S, 13S, 14S, 15S, 16S, 17S Region 100, 100A, 100B, 100C, 100D, 100E, 100F For measurement Component 100a Optical connector 100b Optical amplifier 101, 101A, 101B, 101D First connection waveguide core part 102, 102A, 102B, 102D Second connection waveguide core part 103, 103A, 103B, 103D Third connection waveguide core part 104 , 104A, 104B, 104D Fourth connecting waveguide core 1 5, 105A, 105B, 105D Fifth connection waveguide core part 106, 106A, 106B, 106D Sixth connection waveguide core part 110, 110A, 110B, 110C, 110D First component 110a, 120a First optical fiber 110b, 120b 2nd optical fiber 110c, 120c 3rd optical fiber 110d, 120d 4th optical fiber 110e, 120e 5th optical fiber 110f, 120f 6th optical fiber 110g, 120g 7th optical fiber 110h, 120h Glass capillary 111, 111B, 111D Light Input waveguide core part 112, 112B, 112D, 112F Waveguide core part 112C Input side second connection waveguide core part 113C Input side third connection waveguide core part 114C Input side fourth connection waveguide core part 115C Input side first 5-connection waveguide core Part 116C input side sixth connection waveguide core part 117C input side seventh connection waveguide core part 120, 120A, 120B, 120C, 120D second part 121C output side first connection waveguide core part 122C output side second connection Waveguide core portion 123C Output side third connection waveguide core portion 124C Output side fourth connection waveguide core portion 125C Output side fifth connection waveguide core portion 126C Output side sixth connection waveguide core portion 130, 140 Capillary for connection 150 First intermediate part 151, 152, 153, 154, 155, 156, 157, 161, 162, 163, 164, 165, 166, 167 Intermediate connection waveguide core part 160 Second intermediate part F Optical fiber O OTDR
CO coherent OTDR

Claims (13)

A measuring component that includes a plurality of core portions and inputs test light to an optical fiber transmission body having a first end and a second end,
A first component having an optical input waveguide core portion connected to the first end portion and connected to the first core portion of the plurality of core portions;
A second component having a first connecting waveguide core portion connected to the second end portion and connecting the first core portion and the second core portion among the plurality of core portions at the second end portion;
A component for measuring an optical fiber transmission body, comprising: The number of the plurality of core portions included in the optical fiber transmission body is N (N is an integer of 3 or more),
The second component includes an n-th connecting conductor that connects an n-th core portion (n is an integer from 1 to N−2) and an (n + 1) -th core portion among the plurality of core portions at the second end portion. Having a waveguide core,
The first component has a (n + 1) -th connected waveguide core portion that connects the (n + 1) -th core portion and the (n + 2) -th core portion among the plurality of core portions at the first end portion. The optical fiber transmission body measurement part according to claim 1.   The first connection waveguide core part, the nth connection waveguide core part, or the (n + 1) th connection waveguide core part is configured by connecting two waveguide core parts via an optical connector. The measurement part of an optical fiber transmission body according to claim 1 or 2.   The first connection waveguide core part, the nth connection waveguide core part, or the (n + 1) th connection waveguide core part is formed by fusion-bonding two waveguide core parts. The measurement part of the optical fiber transmission body according to claim 1 or 2.   The first connection waveguide core part, the nth connection waveguide core part, or the (n + 1) th connection waveguide core part is formed inside an optical part constituting the first part or the second part. The measurement part of an optical fiber transmission body according to any one of claims 1 to 4. A measuring component that includes a plurality of core portions and inputs test light to an optical fiber transmission body having a first end and a second end,
When the number of the plurality of core portions included in the optical fiber transmission body is N (N is an integer of 2 or more),
An optical input waveguide core part connected to the first end part for inputting light to the first core part among the plurality of core parts, and (n + 1) th of the plurality of core parts at the first end part. A first component having an input side (n + 1) -connected waveguide core portion connected to a core portion (n is an integer from 1 to N-1);
A second component connected to the second end portion and having an output-side n-th connecting waveguide core portion connected to the n-th core portion among the plurality of core portions at the second end portion;
The output side n-th connected waveguide core part and the input side (n + 1) th connected waveguide core part are connected to each other.   The optical fiber transmission body according to claim 6, wherein the output side n-th connection waveguide core part and the input side (n + 1) th connection waveguide core part are connected via an optical connector. Measuring parts.   7. The optical fiber transmission body measurement according to claim 6, wherein the output side n-th connected waveguide core part and the input side (n + 1) th connected waveguide core part are fusion-spliced. parts.   The mode field diameter of the plurality of core portions included in the optical fiber transmission body and the mode field diameter of each of the waveguide core portions are different from each other. Measurement parts for optical fiber transmissions. The interval between the plurality of core portions of the optical fiber transmission body and the interval between the plurality of waveguide core portions on the connection end surface of the first component are different,
The interval between the plurality of core portions of the optical fiber transmission body and the interval between the plurality of waveguide core portions on the connection end surface of the second component are different,
Of the waveguide core portions of the first component, only some of the plurality of waveguide core portions are connected so that the connection loss with the core portion of the optical fiber transmission body is a predetermined value or less,
Of the waveguide core portions of the second component, only some of the plurality of waveguide core portions are connected so that a connection loss with the core portion of the optical fiber transmission body is a predetermined value or less. The measurement part of the optical fiber transmission body according to any one of claims 1 to 9. A plurality of intermediate connection waveguides connected between the optical fiber transmission body and the first component and respectively connecting a plurality of core portions of the optical fiber transmission body and a plurality of waveguide core portions of the first component A first intermediate part having a core part;
A plurality of intermediate connection waveguides connected between the optical fiber transmission body and the second part and respectively connecting a plurality of core parts of the optical fiber transmission body and a plurality of waveguide core parts of the second part A second intermediate part having a core part;
With
The interval between the plurality of core portions of the optical fiber transmission body and the interval between the plurality of waveguide core portions on the connection end surface of the first component are different,
The interval between the plurality of core portions of the optical fiber transmission body and the interval between the plurality of waveguide core portions on the connection end surface of the second component are different,
The intervals between the plurality of intermediate connection waveguide core portions in the first intermediate component are the intervals between the plurality of core portions of the optical fiber transmission body and the plurality of waveguide core portions at the connection end surface of the first component. Is the value between the intervals,
The intervals between the plurality of intermediate connection waveguide core portions in the second intermediate component are the intervals between the plurality of core portions of the optical fiber transmission body and the plurality of waveguide core portions at the connection end surface of the second component. The measurement part of the optical fiber transmission body according to any one of claims 1 to 9, wherein the measurement part is a value between the intervals. An optical fiber transmission body measurement method using the optical fiber transmission body measurement part according to any one of claims 1 to 11,
Test light is input to the first core part of the optical fiber transmission body from the optical input waveguide core part by OTDR, and backscattered light from each core part of the optical fiber transmission body is measured. Measuring method of optical fiber transmission body.   The method of measuring an optical fiber transmission body according to claim 12, wherein the OTDR is a coherent OTDR.

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