Fiber core power coupler and fixed optical add / drop multiplexer

Abstract

The present disclosure provides a core power coupler and a fixed optical add / drop multiplexer, which are applied in the field of optical fiber communication. The core power coupler includes: a connector, wherein the first end of the connector has N first core interfaces and M second core interfaces, and the first end of the connector is used to connect the first optical fiber, the first optical fiber has N+M cores, each core is connected to a first core interface or a second core interface, N≥1, M≥0; a coupling part, wherein N single-mode optical fibers are arranged inside, each single-mode optical fiber is coupled to a first core interface respectively, and the coupling part is used to couple the signal of the core connected to the first core interface into the single-mode optical fiber, or, to couple the signal of the single-mode optical fiber into the core connected to the first core interface. The embodiments of the present disclosure can realize specific core up and down waves with extremely low link loss in a multi-core optical fiber system.

Description

Technical Field

[0001] The present disclosure relates to the technical field of optical fiber communication, and in particular to a fiber core power coupler and a fixed optical add / drop multiplexer using the fiber core power coupler. Background Art

[0002] In the FOADM (Fixed Optical Add-Drop Multiplexer) networking structure, corresponding TFF (Thin Film Filter) devices are required to implement the uplink and downlink of different services (i.e., signal download and upload). At the same time, in the networking, it is not necessary for all services carried by the fiber cores to implement uplink and downlink (i.e., signal download and upload). In order not to increase the link loss of other fiber cores, it is necessary to implement uplink and downlink of specific fiber cores in the multi-core optical fiber system.

[0003] The existing method is to use a fan-in and fan-out device to divide the cores of a multi-core optical fiber into multiple single-mode optical fibers, connect the optical fiber of one of the cores to the TFF device, and then all the cores need to be connected to another fan-in and fan-out device through a single-mode LC connector, ultimately achieving up and down wave operations on specific cores in the multi-core optical fiber.

[0004] This method requires the introduction of two additional fan-in and fan-out devices, which increases the overall link loss, especially the link loss of the fiber cores that do not need to perform add / drop operations, and increases the overall cost. Therefore, a method is needed to achieve the addition and drop of a certain fiber core or several fiber cores in a multi-core optical fiber system without increasing the link loss.

[0005] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0006] The purpose of the present disclosure is to provide a core power coupler and a fixed optical add / drop multiplexer using the core power coupler, which are used to implement specific core add / drop wave in a multi-core optical fiber system without increasing link loss.

[0007] According to a first aspect of the present disclosure, there is provided a core power coupler, comprising:

[0008] A connector, wherein the first end of the connector has N first fiber core interfaces and M second fiber core interfaces, the first end of the connector is used to connect a first optical fiber, the first optical fiber has N+M fiber cores, each fiber core is correspondingly connected to a first fiber core interface or a second fiber core interface, N≥1, M≥0;

[0009] The coupling part has N single-mode optical fibers arranged inside, each of which is coupled to a first core interface respectively. The coupling part is used to couple the signal of the core connected to the first core interface into the single-mode optical fiber, or to couple the signal of the single-mode optical fiber into the core connected to the first core interface.

[0010] In an exemplary embodiment of the present disclosure, the second end of the connector has M third fiber core interfaces correspondingly connected to the M second fiber core interfaces, and the second end of the connector is used to connect the second optical fiber, the second optical fiber has M fiber cores, and each fiber core of the second optical fiber is correspondingly connected to a third fiber core interface.

[0011] In an exemplary embodiment of the present disclosure, the second end of the connector has N+M third fiber core interfaces correspondingly connected to the N first fiber core interfaces and the M second fiber core interfaces. The second end of the connector is used to connect the second optical fiber, the second optical fiber has N+M fiber cores, and each fiber core of the second optical fiber is correspondingly connected to a third fiber core interface.

[0012] In an exemplary embodiment of the present disclosure, the coupling portion has one or more first single fiber core signal connection ends, the first single fiber core signal connection end and the second end of the connector are arranged in the same direction, the first single fiber core signal connection end is used to connect to the core of the third optical fiber, and the third optical fiber is used to perform signal wave removal on the core connected to the first fiber core interface.

[0013] In an exemplary embodiment of the present disclosure, the coupling portion has one or more second single fiber core signal connection ends, the second single fiber core signal connection ends are arranged in the same direction as the first end of the connector, the second single fiber core signal connection ends are used to connect to the core of a fourth optical fiber, and the fourth optical fiber is used to carry out signal wavecasting on the core connected to the first fiber core interface.

[0014] In an exemplary embodiment of the present disclosure, the distance between the coupling portion and any one of the first core interfaces is smaller than the distance between the coupling portion and any one of the second core interfaces.

[0015] In an exemplary embodiment of the present disclosure, it is manufactured in the following manner:

[0016] A single fiber core disposed in a first fiber core interface and a single-mode optical fiber are placed on the flame head for taper drawing;

[0017] The temperature of the flame head and the speed of the taper are controlled to control the proximity distance between the single fiber core and the single-mode optical fiber, thereby adjusting the taper length until the single fiber core and the single-mode optical fiber reach the set coupling ratio.

[0018] In an exemplary embodiment of the present disclosure, it is manufactured in the following manner:

[0019] Place a single fiber core disposed in a first fiber core interface and a single-mode optical fiber on a first base and a second base respectively, and polish the side surfaces of the single fiber core and the single-mode optical fiber respectively;

[0020] Adjust the polishing depth, polishing length, and the proximity distance between the single fiber core and the single-mode fiber until the single fiber core and the single-mode fiber reach the set coupling ratio;

[0021] The single fiber core and the single-mode optical fiber are bonded together using a refractive index matching liquid, and the first base and the second base are cured using ultraviolet glue.

[0022] According to a second aspect of the present disclosure, there is provided a fixed optical add / drop multiplexer, comprising:

[0023] A first connection end, used for connecting a first optical fiber, the first optical fiber having N+M fiber cores, N≥1, M≥0;

[0024] A first fiber core power coupler, as claimed in any one of claims 1 to 8, connected to the first connection end to connect to the first optical fiber, the first fiber core power coupler having N first fiber core interfaces and M second fiber core interfaces;

[0025] A second connection end is used to connect a fifth optical fiber, the fifth optical fiber has P+M fiber cores, P≥1;

[0026] A second fiber core power coupler, as claimed in any one of claims 1 to 8, connected to the second connection end to connect to the fifth optical fiber, the second fiber core power coupler having P first fiber core interfaces and M second fiber core interfaces;

[0027] One or more thin film filters, wherein the thin film filters are used to connect the coupling part of the first fiber core power coupler through the third optical fiber, and are used to connect the coupling part of the second fiber core power coupler through the fourth optical fiber. The thin film filters are used to perform at least one of the following functions: filtering and passing through the signal from the third optical fiber, wavecasting the signal to the third optical fiber, filtering and passing through the signal from the fourth optical fiber, and wavecasting the signal to the fourth optical fiber.

[0028] In an exemplary embodiment of the present disclosure, the fixed optical add / drop multiplexer further includes a second optical fiber connected between the first core power coupler and the second core power coupler.

[0029] In an exemplary embodiment of the present disclosure, the first optical fiber is used to input a signal, the thin film filter has a signal output end, the thin film filter is connected to the third optical fiber, and the thin film filter is used to filter the signal from the third optical fiber to output a first signal through the signal output end.

[0030] In an exemplary embodiment of the present disclosure, the thin film filter is also connected to a fourth optical fiber, and the thin film filter is used to filter the signal from the third optical fiber to output the first signal through the signal output end, retain the second signal, and transmit the second signal to the second core power coupler through the fourth optical fiber.

[0031] In an exemplary embodiment of the present disclosure, the first optical fiber is used for inputting signals, the fifth optical fiber is used for outputting signals, the thin film filter is connected to the fourth optical fiber, the thin film filter has a signal input end, the thin film filter receives a third signal through the signal input end, and transmits the third signal to the second core power coupler through the fourth optical fiber.

[0032] The core power coupler provided in the embodiment of the present disclosure can extract the signal of a specific core in a multi-core optical fiber (signal down wave), or add a signal to a specific core in a multi-core optical fiber (signal up wave) without increasing the link loss. The FOADM device using the core power coupler has the function of adding and dropping waves for a specific core in a multi-core optical fiber, and the link loss and cost are extremely low.

[0033] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification are used to explain the principles of the present disclosure. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0035] Figure 1 It is a schematic structural diagram of a fiber core power coupler in an exemplary embodiment of the present disclosure.

[0036] Figure 2A to Figure 2D Schematic diagram of the cross section of the fiber core power coupler in the embodiment of the present disclosure.

[0037] Figure 3A and Figure 3B Schematic diagram of the output of the fiber core power coupler in the embodiment of the present disclosure.

[0038] Figure 4A to Figure 4C Schematic diagram of the ports of the coupling portion in the embodiment of the present disclosure.

[0039] Figure 5 It is a schematic diagram of manufacturing a fiber core power coupler in one embodiment of the present disclosure.

[0040] Figure 6It is a schematic diagram of manufacturing a fiber core power coupler in another embodiment of the present disclosure.

[0041] Figure 7A to Figure 7C is a schematic diagram of a fixed optical add / drop multiplexer in an exemplary embodiment of the present disclosure.

[0042] Figure 8A to Figure 8C It is a schematic diagram of a fixed optical add / drop multiplexer 700 completing signal adding and dropping in an embodiment of the present disclosure.

[0043] Figures 9A to 9C It is a schematic diagram of a fixed optical add / drop multiplexer 700 completing signal adding and dropping in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0044] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as being limited to the examples set forth herein; on the contrary, these embodiments are provided so that the present disclosure will be more comprehensive and complete, and the concepts of the example embodiments are fully conveyed to those skilled in the art. The described features, structures, or characteristics may be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present disclosure. However, those skilled in the art will appreciate that the technical solutions of the present disclosure may be practiced while omitting one or more of the specific details, or other methods, components, devices, steps, etc. may be adopted. In other cases, known technical solutions are not shown or described in detail to avoid obscuring various aspects of the present disclosure.

[0045] In addition, the accompanying drawings are only schematic diagrams of the present disclosure, and the same reference numerals in the drawings represent the same or similar parts, so their repeated description will be omitted. Some of the block diagrams shown in the accompanying drawings are functional entities, which do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in software form, or implemented in one or more hardware modules or integrated circuits, or implemented in different networks and / or processor devices and / or microcontroller devices.

[0046] The exemplary embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.

[0047] Figure 1 It is a schematic structural diagram of a fiber core power coupler in an exemplary embodiment of the present disclosure.

[0048] refer to Figure 1 , the core power coupler 100 may include:

[0049] Connector 1, wherein the first end of the connector 1 has N first fiber core interfaces 11 and M second fiber core interfaces 12, and the first end of the connector 1 is used to connect a first optical fiber 10, and the first optical fiber 10 has N+M fiber cores, and each fiber core is correspondingly connected to a first fiber core interface 11 or a second fiber core interface 12, where N≥1 and M≥0;

[0050] The coupling part 2 is provided with N single-mode optical fibers 21 inside, and each single-mode optical fiber 21 is coupled to a first core interface 11 respectively. The coupling part 2 is used to couple the signal of the core connected to the first core interface 11 to the single-mode optical fiber 21, or to couple the signal of the single-mode optical fiber 21 to the core connected to the first core interface 11.

[0051] The first optical fiber 10 is a multi-core optical fiber having N+M cores.

[0052] The first fiber core interface 11 and the second fiber core interface 12 are identical in structure, and only differ in function and position. Figure 1 For the purpose of illustration, the first fiber core interface 11 and the second fiber core interface 12 are shown as being located relatively far away from each other. In fact, the positional relationship between the two can be seen in the subsequent FIG. 2 .

[0053] A single fiber core is disposed in each of the first fiber core interface 11 and the second fiber core interface 12 to connect the signal transmission path of each fiber core in the first optical fiber 10. In some embodiments, a fiber core positioning device may also be disposed in the first fiber core interface 11 and the second fiber core interface 12 to ensure that when the fiber core in the first optical fiber 10 is connected to the first fiber core interface 11 or the second fiber core interface 12, it can be accurately docked with the single fiber core inside the first fiber core interface 11 or the second fiber core interface 12. In addition, when the first optical fiber 10 is connected to the first end of the connector 1, each fiber core in the first optical fiber 10 may be flattened first so that each fiber core in the first optical fiber 10 can be accurately docked with the single fiber core inside the first fiber core interface 11 or the second fiber core interface 12.

[0054] In some embodiments, N=1, the fiber core power coupler 100 can be used to realize signal uploading (wave loading) and signal downloading (wave dropping) of a single fiber core. In some other embodiments, N>1, in this case, the fiber core power coupler 100 can be used to realize signal uploading (wave loading) and signal downloading (wave dropping) of multiple specific fiber cores.

[0055] Since the first fiber core interface 11 and the second fiber core interface 12 are configured the same, when connecting the first optical fiber 10, N fiber cores can be optionally connected to the first fiber core interface 11, and the remaining M fiber cores can be connected to the second fiber core interface 12. In addition, specific N fiber cores can also be connected to the first fiber core interface 11, and those skilled in the art can set it according to actual needs.

[0056] The coupling part 2 is tightly connected to the internal structure of the first fiber core interface 11, and at the same time, the coupling part 2 is as far away from the second fiber core interface 12 as possible to avoid wrong coupling. In the embodiment of the present disclosure, the distance between the coupling part 2 and any one of the first fiber core interfaces 11 is smaller than the distance between the coupling part 2 and any one of the second fiber core interfaces 12.

[0057] The single-mode optical fiber 21 has only a single core. Each single-mode optical fiber 21 is connected to a corresponding first core interface 11 , and the single-mode optical fiber 21 in the coupling part 2 is coupled with the single core in the first core interface 11 .

[0058] In some embodiments, the remaining value of the signal in the single-mode optical fiber 21 or the single core in the first core interface 11 after the single-mode optical fiber 21 is coupled to the single core in the first core interface 11 can be determined by adjusting the coupling ratio during manufacturing. For example, when it is necessary to drop the specific core signal of the first optical fiber 10, according to different coupling ratios during manufacturing, after the single-mode optical fiber 21 is coupled to the single core in the first core interface 11, part of the signal (for example, 50%) or all of the signal in the single core in the first core interface 11 can be transmitted to the single-mode optical fiber 21, and then output through the single-mode optical fiber 21, so as to achieve the download (drop) of the optical signal. When it is necessary to upload a signal to a specific core of the first optical fiber 10 through the single-mode optical fiber 21, depending on the different coupling ratios during manufacturing, it can be achieved that after the single-mode optical fiber 21 is coupled with the single core in the first core interface 11, part of the signal (for example, 50%) or all of the signal in the single-mode optical fiber 21 is transmitted to the single core in the first core interface 11, and then output through the first core interface 11, thereby realizing the upload (uploading) of the optical signal.

[0059] Figure 2A to Figure 2D 2 is a cross-sectional schematic diagram of a core power coupler in an embodiment of the present disclosure. The outline of the core power coupler shown in FIG2 is for illustration only and does not limit the actual outline of the core power coupler.

[0060] refer to Figure 2A , in one embodiment, N=1, M=3. The core power coupler 100 can be formed by a multi-core optical fiber and a single-mode optical fiber core being close to each other, and the direction in which the single-mode optical fiber 21 and the first optical fiber 10 are close to each other can be used to determine which core's energy can be coupled. For example, when the single-mode optical fiber 21 is on the extension line of the diameter of the core 1, the energy coupling between the core 1 and the single-mode optical fiber 21 is achieved. Since the other cores are far away, coupling cannot be achieved. In this scenario, the interface connecting the core 1 is the first core interface 11, and the interface connecting the cores 2, 3, and 4 is the second core interface 12. By controlling the close distance, coupling length, and coupling ratio of the cores, partial (less than 100%) or full (100%) coupling of the energy between the core 1 and the single-mode optical fiber 21 can be achieved.

[0061] In one embodiment of the present disclosure, when it is necessary to implement signal drop for a specific core of the first optical fiber 10, the connector 1 can either continue to transmit the signal of the core connected to the first core interface 11 (even if the signal is empty after coupling), or only transmit the signal of the core connected to the second core interface 12. When it is necessary to implement signal drop for a specific core of the first optical fiber 10, the connector 1 needs to continue to transmit the signal of the core connected to the first core interface 11.

[0062] When N is greater than 1, the position and shape of the coupling portion 2 can be set according to the positions of the fiber core interfaces in the connector 1 .

[0063] refer to Figure 2B When the fiber core interfaces in the connector 1 are arranged in an array, the coupling part 2 can be arranged around the connector 1. Figure 2B On the left side, N=2, M=2, Figure 2B On the right side, N=4, M=0.

[0064] refer to Figure 2C In another embodiment, when the fiber core interfaces in the connector 1 are arranged in an array, the coupling portion 2 can also be set according to the position of the first fiber core interface 11. Figure 2C On the left side, N=2, M=2, the cross-sections of the coupling portion 2 and the connector 1 are both arc surfaces; Figure 2C On the right side, N=2, M=2, and the cross-sections of the coupling portion 2 and the connector 1 are both rectangular.

[0065] refer to Figure 2D In another embodiment, the coupling part 2 can be divided into a plurality of sub-coupling parts 20 according to the position of the first fiber core interface 11 , and each sub-coupling part 20 is respectively arranged corresponding to one first fiber core interface 11 . Figure 2D On the left side, N=2, M=2, Figure 2D On the right side, N=4, M=0.

[0066] In other embodiments, if the positions of the fiber core interfaces in the connector 1 are arranged in other ways, such as a straight line arrangement, a cross star arrangement, a triangle arrangement, etc., the coupling part 2 is also arranged accordingly according to the positions of the fiber core interfaces, and the various shapes of the coupling part 2 are all within the scope of the embodiments of the present disclosure.

[0067] Figure 3A and Figure 3B Schematic diagram of the output of the fiber core power coupler in the embodiment of the present disclosure.

[0068] refer to Figure 3AIn one embodiment, the second end of the connector 1 has M third fiber core interfaces 13 correspondingly connected to the M second fiber core interfaces 12. The second end of the connector 1 is used to connect the second optical fiber 20. The second optical fiber 20 has M fiber cores, and each fiber core is correspondingly connected to a third fiber core interface 13. The second fiber core interface 12 and the third fiber core interface 13 are connected through a single fiber core 121.

[0069] exist Figure 3A In the illustrated embodiment, the connector 1 only outputs the signal of the fiber core connected to the second fiber core interface 12, and the signal of the fiber core connected to the first fiber core interface 11 is output by the coupler 2 for processing. Figure 3A The connector 1 shown can only achieve the downlink of a specific optical fiber signal.

[0070] refer to Figure 3B In another embodiment, the second end of the connector 1 has N+M third fiber core interfaces 13, and the second end of the connector 1 is used to connect the second optical fiber 20. The second optical fiber 20 has N+M fiber cores, and each fiber core is connected to a corresponding third fiber core interface 13. The second fiber core interface 12 and the third fiber core interface 13 are connected through a single fiber core 121, and the N third fiber core interfaces 13 are respectively connected to the N first fiber core interfaces 12 through N single fiber cores 111.

[0071] exist Figure 3B In the illustrated embodiment, a signal may or may not exist in the single core 111. In the signal drop-out scenario, depending on the different coupling ratios between the single core 111 and the single-mode optical fiber 21, part of the signal or all of the signal in the single core 111 is coupled into the single-mode optical fiber 21. When part of the signal in the single core 111 is coupled into the single-mode optical fiber 21, part of the signal is still retained in the single core 111, and the intensity of the part of the signal is less than the signal intensity in the corresponding core in the first optical fiber 10. When all the signals in the single core 111 are coupled into the single-mode optical fiber 21, no signal exists in the single core 111. In the signal add-in scenario, the signal of the single-mode optical fiber 21 is coupled into the single core 111, and there must be a signal in the single core 111.

[0072] Figure 3B The illustrated embodiment can be applied to signal wave addition and signal wave removal scenarios, and has a wider range of application scenarios. Therefore, a second optical fiber 20 having the same specifications as the first optical fiber 10 can be configured to be connected to the output end of the connector 1 to improve the signal transmission quality and increase the connection strength. The same specifications include but are not limited to the same core diameter, the same core cross-sectional shape, the same core size, the same core material, the same number of cores, the same core spacing, and the same core refractive index.

[0073] Figure 4A to Figure 4C Schematic diagram of the ports of the coupling portion in the embodiment of the present disclosure.

[0074] refer to Figure 4A In one embodiment, the coupling portion 2 has N first single fiber core signal connection ends 22, and the first single fiber core signal connection end 22 and the second end of the connector 1 are arranged in the same direction. The N first single fiber core signal connection ends 22 are used to respectively connect to the N fiber cores of the third optical fiber 30, and the third optical fiber 30 is used to collect signals from the N fiber cores in the first optical fiber 10. Figure 4A The embodiment shown can be applied Figure 3A , Figure 3B The two types of third fiber core interfaces 13 in the illustrated embodiment will not be described in detail.

[0075] The coupling part 2 can be connected to a subsequent optical signal processing device such as a TFF device (see subsequent embodiments) through a third optical fiber 30, thereby providing a wavelet path for the optical signal.

[0076] refer to Figure 4B In one embodiment, the coupling portion 2 has N second single fiber core signal connection ends 23 , and the second single fiber core signal connection ends 23 and the first end of the connector 1 are arranged in the same direction.

[0077] When a TFF device (thin film filter 75) can only be connected to one single-mode optical fiber, the N second single-core signal connection ends 23 are used to respectively connect N fourth optical fibers 40, wherein the fourth optical fiber 40 is a single-mode optical fiber, and the fourth optical fiber 40 is used to add a signal to a core in the first optical fiber 10 to complete the signal wave.

[0078] When the input or output end of a TFF device can be connected to a multi-core optical fiber, that is, when signals from different cores are processed at different time periods through a thin film filter 75, the fourth optical fiber 40 can also be a multi-core optical fiber, and the number of cores of the fourth optical fiber 40 is equal to the number of cores that can be connected to the input or output end of the thin film filter 75 used to connect the fourth optical fiber 40, and the number of fourth optical fibers 40 is equal to the ratio of N to the number of cores of the fourth optical fiber 40.

[0079] Understandably, Figure 4B The embodiment shown can only be applied Figure 3B The third fiber core interface 13 and the second optical fiber 20 in the illustrated embodiment.

[0080] The coupling part 2 can be connected to a subsequent optical signal processing device such as a TFF device (see subsequent embodiments) through a fourth optical fiber 40, thereby providing an optical signal wave-adding path.

[0081] By forming two types of fiber core power couplers 100 with different interface setting directions, it is possible to achieve functional independence, save costs, and adapt to different scenarios. In addition, the two types of fiber core power couplers can be used in conjunction with different parts of the same optical fiber to complete the addition and removal of specific fiber cores.

[0082] refer to Figure 4C In one embodiment, a first single fiber core signal connection end 22 and a second single fiber core signal connection end 23 can be set at the same time. At this time, when it is necessary to perform signal addition and signal removal on a specific fiber core in the first optical fiber 10, a fiber core power coupler can be used to connect the specific fiber core in the first optical fiber 10 to perform signal removal and signal addition, and then the signal output can be realized by connecting the second optical fiber 20 to the second end of the connector 1.

[0083] When the first single fiber core signal connection end 22 and the second single fiber core signal connection end 23 are provided at the same time, the number of the first single fiber core signal connection end 22 and the second single fiber core signal connection end 23 may be less than N (the number of the first fiber core interfaces 11).

[0084] In one embodiment, a cores in the first optical fiber 10 can be selected to perform signal dropout and b cores can be selected to perform signal add-on. If a core and b core do not overlap, then a+b=N (N must be greater than 1 at this time), the number of first single core signal connection ends 22 is a, and the number of second single core signal connection ends 23 is b.

[0085] In another embodiment, if c cores in the first optical fiber 10 are selected to perform signal dropout and d cores are selected to perform signal uplink, e cores among the c cores and d cores overlap, that is, uplink and dropout (or dropout and uplink) are performed on the e cores in sequence according to the coupling positions, then c+de=N (N can be greater than or equal to 1), the number of the first single core signal connection ends 22 is c, and the number of the second single core signal connection ends 23 is d. It can be understood that, Figure 4C The embodiment shown can only be applied Figure 3B The third fiber core interface 13 and the second optical fiber 20 in the illustrated embodiment.

[0086] Figure 5 It is a schematic diagram of manufacturing a fiber core power coupler in one embodiment of the present disclosure.

[0087] refer to Figure 5 In one embodiment, the fiber core power coupler 100 can be prepared by a strong coupling taper method.

[0088] First, a single fiber core 111 set in a first fiber core interface 11 and a single-mode optical fiber 21 are placed on a flame head for taper pulling. Then, the temperature of the flame head and the speed of taper pulling are controlled to control the approach distance between the single fiber core 111 and the single-mode optical fiber 21, and the taper pulling length is adjusted at the same time until the single fiber core 111 and the single-mode optical fiber 21 reach the set coupling ratio.

[0089] Figure 6 It is a schematic diagram of manufacturing a fiber core power coupler in another embodiment of the present disclosure.

[0090] refer to Figure 6 In another embodiment, the fiber core power coupler can also be prepared by polishing.

[0091] First, a single fiber core 111 and a single-mode optical fiber 21 set in a first fiber core interface 11 are placed on the first base 61 and the second base 62, respectively, and the sides of the single fiber core 111 and the single-mode optical fiber 21 are polished respectively. Then, the polishing depth (determines the proximity distance between the single fiber core 111 and the single-mode optical fiber 21) and the polishing length are adjusted until the single fiber core 111 and the single-mode optical fiber 21 reach the set coupling ratio. Finally, the refractive index matching liquid is used to make the single fiber core 111 and the single-mode optical fiber 21 fit together, and the first base 61 and the second base 62 are cured using ultraviolet glue.

[0092] The embodiment of the present disclosure is only exemplified by using one single-mode optical fiber coupled to a single fiber core 111. In some embodiments, two or more single-mode optical fibers may be coupled to a single fiber core 111, so that the single fiber core 111 may be transmitted to different directions, such as different thin film filters 75 (see Fig. 7A ), or from different directions, such as from different thin film filters 75 (see Fig. 7A ) is coupled into the single fiber core 111.

[0093] The fiber core power coupler 100 can cooperate with the TFF device to realize the up and down waves of a specific fiber core.

[0094] The following shows the networking scenario of FOADM (Fixed Optical Add / Drop Multiplexer) in a multi-core optical fiber system.

[0095] Figure 7A to Figure 7C is a schematic diagram of a fixed optical add / drop multiplexer in an exemplary embodiment of the present disclosure.

[0096] refer to Fig. 7A , the fixed optical add / drop multiplexer (FOADM) 700 may include:

[0097] A first connection end 71, used for connecting to a first optical fiber 10, the first optical fiber 10 having N+M fiber cores, N≥1, M≥0;

[0098] The first fiber core power coupler 72, as shown in the above embodiment, is connected to the first connection end 71 to connect to the first optical fiber 10, and the first fiber core power coupler 72 has N first fiber core interfaces and M second fiber core interfaces;

[0099] The second connection end 73 is used to connect to the fifth optical fiber 50, and the fifth optical fiber 50 has P+M fiber cores, where P≥1;

[0100] The second fiber core power coupler 74, as shown in the above embodiment, is connected to the second connection end 73 to connect to the fifth optical fiber 50, and the second fiber core power coupler 74 has P first fiber core interfaces and M second fiber core interfaces;

[0101] One or more thin film filters 75, the thin film filter 75 is used to connect the coupling part of the first core power coupler 72 through the third optical fiber 30, and is used to connect the coupling part of the second core power coupler 74 through the fourth optical fiber 40. The thin film filter 75 is used to complete at least one of the following functions: filtering and passing the signal from the third optical fiber 30, wave-adding the signal to the third optical fiber 30, filtering and passing the signal from the fourth optical fiber 40, and wave-adding the signal to the fourth optical fiber 40.

[0102] The third optical fiber 30 is provided with a first power monitor 31, and the fourth optical fiber 40 is provided with a second power monitor 41. Those skilled in the art may set power monitors at multiple locations, and the present disclosure does not impose any special restrictions on this. The first fiber core power coupler 72 and the second fiber core power coupler 74 are as shown in any of the above embodiments.

[0103] In one embodiment of the present disclosure, the fixed optical add / drop multiplexer 700 further includes a second optical fiber 20, which is connected between the first core power coupler 72 and the second core power coupler 74. In one embodiment, the second optical fiber 20 has M cores. When M=0, the second optical fiber 20 may not be provided.

[0104] In some embodiments, P=N, that is, the number of first core interfaces of the first core power coupler 72 is equal to the number of first core interfaces of the second core power coupler 74. In other embodiments, P is greater than N or less than N.

[0105] In some embodiments, the thin film filter 75 can only be used to perform signal pass-through, filtering and other signal drop-out operations, or can only be used to perform signal upload operations. In other embodiments, the thin film filter 75 can simultaneously perform signal pass-through, filtering and other signal drop-out operations, as well as signal upload operations.

[0106] In some embodiments, when the thin film filter 75 can only be used to complete signal pass-through, filtering and other signal wavelet operations, or can only be used to complete signal wavelet operations, the input end of one side of the thin film filter 75 can usually only be connected to one single-mode optical fiber. In other embodiments, the input end of one side of the thin film filter 75 can also be connected to multiple single-mode optical fibers, or a multi-core optical fiber.

[0107] When the thin film filter 75 can only be used to complete signal dropout operations such as signal pass-through and filtering, or can only be used to complete signal upload operations, and the input end of one side of the thin film filter 75 can only be connected to one single-mode optical fiber, the thin film filter 75 can be used only for signal dropout, can also be used only for signal upload, and can also be used for signal dropout and pass-through. If N>1 or P>1, there are multiple thin film filters 75.

[0108] at this time:

[0109] (1) If the thin film filter 75 is used only for signal dropout, N thin film filters 75 may be provided to be connected to the first core power coupler 72 through N third optical fibers 30 , respectively.

[0110] (2) If the thin film filter 75 is used only for signal addition, P thin film filters 75 may be provided to be connected to the second core power coupler 74 through P fourth optical fibers 40 , respectively.

[0111] (3) If N thin film filters 75 are used for signal filtering and penetration, the N thin film filters 75 can be connected to the first core power coupler 72 through N third optical fibers 30 respectively, and the N thin film filters 75 can be connected to the second core power coupler 74 through N fourth optical fibers 40 respectively.

[0112] Therefore, when there are multiple thin film filters 75, if some thin film filters 75 are used for signal dropout, some thin film filters are used for signal up-conversion, and some thin film filters 75 are used for signal pass-through and dropout, one thin film filter 75 is connected to at least one third optical fiber 30 and / or fourth optical fiber 40, and the number of thin film filters 75 is greater than or equal to the maximum value of N or P, and less than N + P. The number of third optical fibers 30 is equal to N, and the number of fourth optical fibers 40 is equal to P.

[0113] Those skilled in the art can set the number and connection relationship of the thin film filters 75 according to signal processing requirements, and the present disclosure does not impose any special limitation on this.

[0114] The first connection end 71 and the second connection end 73 are both multi-core fiber LC connectors. The LC connector is a miniaturized fiber optic connector that is very suitable for high-density construction environments. The LC connector has two semi-inserted ceramic sleeves, which are connected by a finely processed and docked ceramic or plastic sleeve to ensure precise alignment between the optical fibers. The LC connector adopts a lead-type structure, and its plug-in and unplug times are as high as 500 to 1000 times, with a long service life. In the optical fiber transmission system, the LC connector can be used for the connection of single-mode and multi-mode optical fibers, and has the advantages of low insertion loss, low return loss, high stability, and good reliability.

[0115] The first optical fiber 10 and the fifth optical fiber 50 are connected to the first core coupler 72 and the second core coupler 74 in the device 700 through the first connecting end 71 and the second connecting end 73, and the splitting of one or some cores is achieved through the coupling part of the first core coupler 72 or the coupling part of the second core coupler 74.

[0116] When the signal is transmitted from the first optical fiber 10 to the fifth optical fiber 50, for the wavelength drop signal (signal drop), after the optical signal of a core split by the first core coupler 72 reaches a thin film filter 75, i.e., a TFF device, through the third optical fiber 30, the thin film filter 75 sends a number of (4 in the figure as an example) fixed wavelength signals to the signal output terminal 76, and passes the signals of other wavelengths through the fourth optical fiber 40 to the single-mode optical fiber of the coupling part in the second core coupler 74, and couples the signal to a core in the fifth optical fiber 50 through the second core coupler 74, thereby completing the signal drop and penetration.

[0117] refer to Figure 7B In some embodiments, other wavelength signals may not be retained or passed through. In this case, the fourth optical fiber 40 may not be provided, and even the second core coupler 74 and the second optical fiber 20 may not be provided, and the second connection end 73 may be directly connected to the right side of the first core coupler 72. Furthermore, the first connection end 71 and the second connection end 73 may not be provided, and the first optical fiber 10 may be directly connected to the left side of the first core coupler 72, and the fifth optical fiber 50 may be connected to the right side of the first core coupler 72.

[0118] Continue to refer Fig. 7A For the wavelength adding signal (signal adding), the optical signal of a certain core after being split by the first core coupler 72 reaches a thin film filter 75, i.e., a TFF device, through the third optical fiber 30, and then is wavelength combined with several (4 in the figure) fixed wavelengths from the signal input end 77 through the thin film filter 75 to achieve wavelength adding, and then is transmitted to the single-mode optical fiber of the coupling part of the second core coupler 74 through the fourth optical fiber 40, coupled to the fifth optical fiber 50, and the signal adding is completed.

[0119] refer to Figure 7C In some embodiments, the signal in the first optical fiber 10 may not be split, and the fourth optical fiber 40 and the second core coupler 74 may be directly used to add the signal to a core of the fifth optical fiber 50. In this case, the third optical fiber 30 may not be provided, and even the first core coupler 72 and the second optical fiber 20 may not be provided, and the first optical fiber 10 may be directly connected to the left side of the second core coupler 74. Furthermore, the first connecting end 71 and the second connecting end 73 may not be provided, and the first optical fiber 10 may be directly connected to the left side of the second core coupler 74, and the fifth optical fiber 50 may be connected to the right side of the second core coupler 74.

[0120] When the signal is transmitted from the fifth optical fiber 50 to the first optical fiber 10, the path is opposite, and the principle is the same, which will not be described in detail here.

[0121] The above signal adding and dropping process is illustrated below with reference to the accompanying drawings.

[0122] Figure 8A to Figure 8C FIG. 1 is a schematic diagram of a fixed optical add / drop multiplexer 700 completing signal addition and drop in an embodiment of the present disclosure. Figure 8A to Figure 8C In the illustrated embodiment, the first optical fiber 10 is used for input signals, and the fifth optical fiber 50 is used for output signals.

[0123] refer to Fig. 8A In one embodiment, the thin film filter 75 has a signal output end 76, and the thin film filter 75 filters the signal from one of the N cores of the third optical fiber 30 to output the first signal S1 through the signal output end 76 and retain the second signal S2; the thin film filter 75 passes the second signal S2 through one core of the fourth optical fiber 40 to the second core power coupler 74 for transmission to the fifth optical fiber 50. Fig. 8A Only one thin film filter 75 is used as an example. In other embodiments, multiple thin film filters 75 may be provided to filter and pass signals of the N cores in the first optical fiber 10 respectively.

[0124] refer to Figure 8B In another embodiment, one thin film filter 75 has a signal output terminal 76, and another thin film filter 75 has a signal input terminal 77. Each thin film filter 75 can only complete wave addition or wave removal, but cannot complete wave addition or wave removal at the same time. Multiple thin film filters 75 are connected to the second core power coupler 74 through different fourth optical fibers 40 (single-mode optical fibers).

[0125] The thin film filter 75 with a signal output end 76 filters the signal from the third optical fiber 30, outputs the first signal S1 through the signal output end 76, retains the second signal S2, and passes the second signal S2 through a fourth optical fiber 40 to the second fiber core power coupler 74; the thin film filter 75 with a signal input end 77 receives the third signal S3 through the signal input end 77, and waves the third signal S3 to the second fiber core power coupler 74 through another fourth optical fiber 40; according to the different internal manufacturing processes of the second fiber core power coupler 74, the second fiber core power coupler 74 can transmit the second signal S2 and the third signal S3 to different cores of the fifth optical fiber 50 respectively, or can transmit the second signal S2 and the third signal S3 to the same core of the fifth optical fiber 50.

[0126] Figure 8B Only one thin film filter 75 is used to realize signal penetration and one thin film filter 75 is used to realize signal wavecasting. In other embodiments, multiple thin film filters 75 can be set to filter and penetrate the signals of the N cores of the first optical fiber 10 respectively, and / or multiple thin film filters 75 are set to respectively carry out signal wavecasting on one or more cores of the fifth optical fiber 50. It should be noted that different thin film filters 75 correspond to different signal output terminals 76 and signal input terminals 77.

[0127] refer to Figure 8C In yet another embodiment, the thin film filter 75 has a signal input terminal 77 , and the thin film filter 75 receives the third signal S3 through the signal input terminal 77 , and then transmits the third signal S3 to the second core power coupler 74 through a fourth optical fiber 40 . Figure 8C In the illustrated embodiment, it is possible to realize waveaddition only for the optical fiber signal. Figure 8C Only one thin film filter 75 is used as an example. In other embodiments, multiple thin film filters 75 may be provided to respectively implement signal addition to one or more cores of the fifth optical fiber 50 .

[0128] Figures 9A to 9C FIG. 1 is a schematic diagram of a fixed optical add / drop multiplexer 700 completing signal addition and drop in an embodiment of the present disclosure. Figures 9A to 9C In the illustrated embodiment, the fifth optical fiber 50 is used for input signals, and the first optical fiber 10 is used for output signals.

[0129] refer to Fig. 9A In one embodiment, the thin film filter 75 has a signal output end 76, and the thin film filter 75 filters the signal from one fourth optical fiber 40 of P fourth optical fibers 40 to output the first signal S1 through the signal output end 76 and retain the second signal S2; the thin film filter 75 transmits the second signal S2 to the first fiber core power coupler 72 through the third optical fiber 30. Fig. 9AOnly one thin film filter 75 is used as an example. In other embodiments, multiple thin film filters 75 may be provided to filter and pass signals of multiple cores of the fifth optical fiber 50 respectively.

[0130] refer to Fig. 9B In another embodiment, one thin film filter 75 has a signal output terminal 76, and another thin film filter 75 has a signal input terminal 77. Each thin film filter 75 can only complete wave addition or wave removal, but cannot complete wave addition or wave removal at the same time. Multiple thin film filters 75 are connected to the first core power coupler 72 through different third optical fibers 30.

[0131] A thin film filter 75 with a signal output end 76 filters a signal from a fourth optical fiber 40, outputs a first signal S1 through the signal output end 76, retains a second signal S2, and transmits the second signal S2 to a first fiber core power coupler 72 through a third optical fiber 30; a thin film filter 75 with a signal input end 77 receives a third signal S3 through the signal input end 77, and waves the third signal S3 to the first fiber core power coupler 72 through another third optical fiber 30; depending on the different internal manufacturing processes of the first fiber core power coupler 72, the first fiber core power coupler 72 can transmit the second signal S2 and the third signal S3 to two different cores of the first optical fiber 10 respectively, or can transmit the second signal S2 and the third signal S3 to the same core of the first optical fiber 10.

[0132] Fig. 9B Only one thin film filter 75 is used for passing through and one thin film filter 75 is used for adding waves. In other embodiments, multiple thin film filters 75 can be provided to filter and pass through the signals of multiple fourth optical fibers 40, and / or multiple thin film filters 75 can be provided to add waves to one or more cores of the first optical fiber 10. Different thin film filters 75 correspond to different signal output terminals 76 and signal input terminals 77, respectively.

[0133] refer to Fig. 9C In yet another embodiment, the thin film filter 75 has a signal input terminal 77 , receives the third signal S3 through the signal input terminal 77 , and transmits the third signal S3 to the first core power coupler 72 through a fourth optical fiber 40 . Fig. 9C In the illustrated embodiment, it is possible to realize waveaddition only for the optical fiber signal. Fig. 9C Only one thin film filter 75 is used as an example. In other embodiments, multiple thin film filters 75 may be provided to respectively implement signal addition to one or more cores of the first optical fiber 10 .

[0134] In addition to the above-mentioned use of different thin film filters 75 to complete signal loading, signal filtering and penetration, in other embodiments of the present disclosure, a plurality of third optical fibers 30 and a plurality of fourth optical fibers 40 can be connected through a thin film filter 75 to successively complete filtering and penetration of different signals, or successively complete signal loading of different cores, or complete filtering and penetration of a signal of a core of an input optical fiber (first optical fiber 10 or fifth optical fiber 50) at a first time point, and complete signal loading of the core at a second time point, the first time point and the second time point being different time points. At this time, the thin film filter 75 can have a signal output terminal 76 and a signal input terminal 77 at the same time.

[0135] In the disclosed embodiment, a multi-core optical fiber is connected to a fixed optical add / drop multiplexer 700 via an LC connector. First, the optical fiber signal of a specific core is split through a core power coupler, and then a fixed add / drop operation is implemented through a thin film filter 75. After passing through the thin film filter 75, another core power coupler is used to implement the transmission of the core signal and other core signals in the same multi-core optical fiber.

[0136] The disclosed embodiments can realize wave addition and subtraction of specific cores in a multi-core optical fiber system. Compared with the existing solutions, it avoids the introduction of fan-in and fan-out devices, reduces the impact on other cores, and greatly reduces the cost.

[0137] It should be noted that, although several modules or units of the device for action execution are mentioned in the above detailed description, this division is not mandatory. In fact, according to the embodiments of the present disclosure, the features and functions of two or more modules or units described above can be embodied in one module or unit. On the contrary, the features and functions of one module or unit described above can be further divided into multiple modules or units to be embodied.

[0138] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are to be considered exemplary only, and the true scope and concept of the present disclosure are indicated by the claims.

Claims

1. A fiber core power coupler, characterized in that: include: A connector, wherein the first end of the connector has N first fiber core interfaces and M second fiber core interfaces, the first end of the connector is used to connect a first optical fiber, the first optical fiber has N+M fiber cores, each of the fiber cores is correspondingly connected to one of the first fiber core interfaces or one of the second fiber core interfaces, N≥1, M>0; A coupling part, in which N single-mode optical fibers are arranged, each of the single-mode optical fibers is coupled to one of the first core interfaces respectively, and the coupling part is used to couple the signal of the core connected to the first core interface into the single-mode optical fiber, or to couple the signal of the single-mode optical fiber into the core connected to the first core interface.

2. The core power coupler according to claim 1, characterized in that: The second end of the connector has M third fiber core interfaces correspondingly connected to the M second fiber core interfaces. The second end of the connector is used to connect a second optical fiber, the second optical fiber has M fiber cores, and each fiber core of the second optical fiber is correspondingly connected to one of the third fiber core interfaces.

3. The core power coupler according to claim 1, characterized in that: The second end of the connector has N+M third fiber core interfaces correspondingly connected to the N first fiber core interfaces and the M second fiber core interfaces. The second end of the connector is used to connect a second optical fiber, the second optical fiber has N+M fiber cores, and each fiber core of the second optical fiber is correspondingly connected to one of the third fiber core interfaces.

4. The core power coupler according to claim 1, characterized in that: The coupling portion has one or more first single-core signal connection ends, and the first single-core signal connection end is arranged on one side of the second end of the connector. The first single-core signal connection end is used to connect to the core of a third optical fiber, and the third optical fiber is used to perform signal dropout, or signal dropout and pass-through on the core connected to the first core interface.

5. The core power coupler according to claim 1 or 4, characterized in that: The coupling portion has one or more second single-core signal connection ends, and the second single-core signal connection ends are arranged on one side of the first end of the connector. The second single-core signal connection ends are used to connect to the core of a fourth optical fiber, and the fourth optical fiber is used to carry out signal wavecasting on the core connected to the first core interface.

6. The core power coupler according to claim 1, characterized in that: The distance between the coupling portion and any one of the first core interfaces is smaller than the distance between the coupling portion and any one of the second core interfaces.

7. The core power coupler according to claim 1, characterized in that: The coupling part is manufactured by: A single fiber core provided in the first fiber core interface and a single-mode optical fiber are placed on the flame head to perform taper drawing; The temperature of the torch and the speed of the taper are controlled to control the proximity distance between the single fiber core and the single-mode optical fiber, thereby adjusting the taper length until the single fiber core and the single-mode optical fiber reach a set coupling ratio.

8. The core power coupler according to claim 1, characterized in that: The coupling part is manufactured by: Place a single fiber core disposed in the first fiber core interface and the single-mode optical fiber on a first base and a second base respectively, and polish the side surfaces of the single fiber core and the single-mode optical fiber respectively; Adjusting the polishing depth, polishing length, and the proximity distance between the single fiber core and the single-mode optical fiber until the single fiber core and the single-mode optical fiber reach a set coupling ratio; The single fiber core and the single-mode optical fiber are bonded together using a refractive index matching liquid, and the first base and the second base are cured using ultraviolet glue.

9. A fixed optical add / drop multiplexer, characterized in that: include: A first connection end, used for connecting a first optical fiber, wherein the first optical fiber has N+M fiber cores, N≥1, M>0; A first fiber core power coupler, as described in any one of claims 1 to 8, connected to the first connection end to connect the first optical fiber, the first fiber core power coupler having N first fiber core interfaces and M second fiber core interfaces; A second connection end is used to connect a fifth optical fiber, wherein the fifth optical fiber has P+M fiber cores, where P≥1; A second fiber core power coupler, as described in any one of claims 1 to 8, connected to the second connection end to connect the fifth optical fiber, the second fiber core power coupler having P first fiber core interfaces and M second fiber core interfaces; One or more thin film filters, wherein the thin film filters are used to connect the coupling part of the first fiber core power coupler through a third optical fiber, and are used to connect the coupling part of the second fiber core power coupler through a fourth optical fiber, and the thin film filters are used to perform at least one of the following functions: filtering and passing through the signal from the third optical fiber, and performing signal addition to the third optical fiber, filtering and passing through the signal from the fourth optical fiber, and performing signal addition to the fourth optical fiber.

10. The fixed optical add / drop multiplexer according to claim 9, characterized in that: The first optical fiber is used for inputting signals, the thin film filter has a signal output end, the thin film filter is connected to the third optical fiber, and the thin film filter is used for filtering the signal from the third optical fiber to output a first signal through the signal output end.

11. The fixed optical add / drop multiplexer according to claim 10, characterized in that: The thin film filter is also connected to the fourth optical fiber, and is used to filter the signal from the third optical fiber to output the first signal through the signal output end, retain the second signal, and transmit the second signal to the second core power coupler through the fourth optical fiber.

12. The fixed optical add / drop multiplexer according to claim 9, characterized in that: The first optical fiber is used for inputting signals, the fifth optical fiber is used for outputting signals, the thin film filter is connected to the fourth optical fiber, the thin film filter has a signal input end, the thin film filter receives a third signal through the signal input end, and transmits the third signal to the second core power coupler through the fourth optical fiber.

Images