JP6339560B2 - Switch device - Google Patents

Description

  The present invention relates to an optical signal switch device, and more particularly to a switch device used for branching and inserting optical signals in wavelength division multiplexing transmission.

  In recent years, ROADM (Reconfigurable Optical Add / Drop Multiplexer) technology has been devised to increase the speed and capacity of optical communications. In an optical network based on ROADM, a wavelength division multiplexing transmission system is used, and an optical signal having an arbitrary wavelength can be branched and inserted without being converted into an electric signal. In addition, in an optical network based on ROADM, when a route through which an optical signal of each wavelength passes is changed (or newly established or abolished), the route is changed without performing work such as connection work, that is, reconfiguration is performed. It is possible (Reconfigurable).

  In order to realize ROADM, a switch device (also referred to as a multicast switch) that can input and output a plurality of wavelengths and can change a route is required. That is, a switch device used in ROADM has a function of receiving an optical signal input from a client device and inserting it into a route of the ROADM network, and a function of outputting an optical signal branched from the route of the ROADM network to the client device. The path through which the optical signal passes can be changed dynamically.

  FIG. 11 is a top view of an example of the switch device 900 used in ROADM. The switch device 900 includes two splitter units 920 and four switch units 930 in a housing 960. Each splitter unit 920 has a predetermined number of optical splitters, and each switch unit 930 has a predetermined number of optical switches. One end of the splitter unit 920 is connected to the ROADM network via the network-side fiber 940, and the other end is branched and connected to one end of the switch unit 930. Further, the other end of the switch unit 930 is connected to the client device via the client side fiber 950. The splitter unit 920 and the switch unit 930 are connected by a shuffle fiber array 970 including a plurality of optical fibers that are three-dimensionally rearranged. With such a configuration, an optical signal can be branched and inserted between the ROADM network and the client device.

  In the switch device 900, since the splitter unit 920 and the switch unit 930 are connected by a plurality of three-dimensionally rearranged optical fibers, each member can be arranged more freely than by a planar optical waveguide circuit (PLC). The degree of expansion is high, and it is easy to change the number of the splitter units 920 and the switch units 930, and the expandability is high.

  In the switch device 900 illustrated in FIG. 11, the optical fibers included in the shuffle fiber array 970 are three-dimensionally rearranged so that the channel arrangement order of the splitter unit 920 corresponds to the channel arrangement order of the switch unit 930. Connected. Here, the three-dimensional recombination means changing the arrangement order at both ends by arranging the optical fibers spatially shifted. Therefore, particularly when the number of inputs / outputs of the splitter unit 920 and the switch unit 930 is large, it takes time to reconnect and connect the optical fibers, and there is a problem that the manufacturing cost of the shuffle fiber array 970 increases. In addition, when the number of optical fibers increases, the handling of the shuffle fiber array 970 in the housing 960 becomes complicated, which causes a problem that the size of the entire switch device 900 increases.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide an optical signal switching device capable of reducing the manufacturing cost and the size.

  One aspect of the present invention is a switch device that performs branching and insertion of an optical signal, a splitter unit for performing splitting and joining of the optical signal, a switch unit for performing path selection of the optical signal, Provided in at least one of the plurality of optical fibers that connect the splitter unit and the switch unit, and the splitter unit and the switch unit, and includes a plurality of optical splitters and is included in the plurality of optical splitters And a cross splitter in which at least some of the waveguides cross each other on a plane.

  According to the present invention, since at least one of the splitter unit and the switch unit is provided with the crossing splitter in which the waveguides cross each other on a plane, the channel arrangement order can be changed only by reconfiguring the optical fiber. The number of optical fibers can be reduced rather than doing so. Therefore, the optical fiber can be easily reassembled, and the manufacturing cost can be reduced. In addition, since the optical fiber can be easily handled in the switch device, the size of the switch device can be reduced.

It is a top view of a switch device concerning one embodiment of the present invention. It is a mimetic diagram of a switch device concerning one embodiment of the present invention. It is a schematic diagram of the crossing splitter which concerns on one Embodiment of this invention. It is a schematic diagram of the crossing splitter which concerns on one Embodiment of this invention. It is a mimetic diagram of a switch device concerning one embodiment of the present invention. It is a schematic diagram of the crossing splitter which concerns on one Embodiment of this invention. It is a schematic diagram of the crossing splitter which concerns on one Embodiment of this invention. It is a schematic diagram of the crossing splitter which concerns on one Embodiment of this invention. It is a mimetic diagram of a switch device concerning one embodiment of the present invention. It is a schematic diagram of the crossing splitter which concerns on one Embodiment of this invention. It is a figure for demonstrating the connection system of the fiber array which concerns on one Embodiment of this invention. It is a figure for demonstrating the connection system of the fiber array which concerns on one Embodiment of this invention. It is a mimetic diagram of a switch device concerning one embodiment of the present invention. It is a figure which shows the cross | intersection part of the waveguides in the cross splitter which concerns on one Embodiment of this invention. It is a figure which shows the cross | intersection part of the waveguides in the cross splitter which concerns on one Embodiment of this invention. It is a top view of the conventional switch apparatus.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the embodiments. In the drawings described below, components having the same function are denoted by the same reference numerals, and repeated description thereof may be omitted.

(First embodiment)
FIG. 1 is a top view of the switch device 100 according to the present embodiment. The switch device 100 can be connected between a ROADM network having a plurality of routes and a plurality of client devices. Thereby, the switch apparatus 100 can branch an optical signal from a route of the ROADM network to a desired client device, or can insert a signal from the client device to a desired route of the ROADM network. In this specification, the number that can be connected to the route of the ROADM network in the switch device 100 is called the number of routes, and the number that can be connected to the client device is called the number of wavelengths. A series of paths (including a waveguide and an optical fiber) through which an optical signal input / output to / from each path passes is called a channel.

The switch device 100 includes one splitter unit 120 and four switch units 130. The splitter unit 120 and the switch unit 130 are housed in a housing 160. One end of the splitter unit 120 is connected to the ROADM network via the network-side fiber 140, and the other end is branched and connected to one end of the plurality of switch units 130. Further, the other end of the switch unit 130 is connected to the client device via the client side fiber 150. The splitter unit 120 and the switch unit 130 are connected by a shuffle fiber array 170 having a plurality of optical fibers 173 that are three-dimensionally rearranged and fiber arrays 171 and 172 formed at both ends of the optical fibers.
In this example, the switch device 100 is illustrated with the number of routes being 8 and the number of wavelengths being 16, but the present invention is not limited to these specific numbers, and any number of routes can be used. And applicable to the number of wavelengths. Further, the number of chips of the splitter unit 120 and the switch unit 130 may be any number of one or more as long as the function of the present invention is not impaired.

  FIG. 2 is a schematic diagram illustrating a wiring method of the switch device 100. The splitter unit 120 includes eight optical splitters 121 on one chip (substrate). The optical splitter 121 used in the present embodiment is a 1 × 4 optical splitter, and has one common port 121a at one end and four branch ports 121b at the other end. The optical signal input from the common port 121a is divided and output to each branch port 121b. Alternatively, the optical signals input from the branch ports 121b are joined to the common port 121a and output. The splitter unit 120 is manufactured using, for example, a PLC formed on a quartz substrate, and the relative refractive index difference Δ between the core and the clad is about 0.4% (0.3% to 0.5%). . By using such a low relative refractive index difference Δ, connection loss can be reduced.

  The splitter unit 120 and the switch unit 130 are connected by a shuffle fiber array 170. The shuffle fiber array 170 includes a splitter-side fiber array 171 connected to the end face of the splitter section 120, a switch-side fiber array 172 connected to the end face of the switch section 130, a splitter-side fiber array 171 and a switch-side fiber array 172. And a plurality (32 in the present embodiment) of optical fibers 173 that are three-dimensionally rearranged. A region having a predetermined length from the end face of the optical fiber 173 is fixed in parallel by a fixing member made of glass or the like to form a splitter-side fiber array 171 and a switch-side fiber array 172.

  By connecting the splitter-side fiber array 171 to the end face of the splitter unit 120, the 32 optical fibers 173 are respectively connected to the branch ports 121 b (32 in total) of the eight optical splitters 121 included in the splitter unit 120. The Since the channels of the optical splitter 121 are not crossed, in the splitter-side fiber array 171, the channels of the 32 optical fibers 173 are arranged in order as 1ch, 1ch, 1ch, 1ch, ˜8ch, 8ch, 8ch, 8ch.

  The 32 optical fibers 173 are three-dimensionally rearranged between the splitter side fiber array 171 and the switch side fiber array 172, and 8 optical fibers 173 of 1ch to 8ch are respectively provided in each of the four switch side fiber arrays 172. Is distributed. In this case, since the optical fibers 173 do not cross each other, no crossing loss occurs. As a result, in each switch-side fiber array 172, the channels of the eight optical fibers 173 are arranged sequentially in the order of 1ch to 8ch. As a result, the arrangement order of the optical fibers 173 and the arrangement order of the branch ports 131b of the optical switch 131 coincide. By connecting the switch-side fiber array 172 to the end face of the switch unit 130, the eight optical fibers 173 included in the switch-side fiber array 172 are connected to the eight optical splitters 181 included in the switch unit 130. Each is connected to a common port 181a (8 in total).

Each switch unit 130 includes four optical switches 131 and a cross splitter 180 including eight optical splitters 181. The optical switch 131 is a 1 × 8 optical switch, and has one common port 131a at one end and eight branch ports 131b at the other end. The optical signal input from the common port 131a is output to one of the branch ports 131b according to control. Alternatively, the optical signal input from each branch port 131b is output to the common port 131a or discarded without being output depending on the control.
The optical switch 131 is manufactured using, for example, a PLC formed on a silicon substrate, and the relative refractive index difference Δ between the core and the clad is about 1.5% (1.4% to 1.6%). . By using such a high relative refractive index difference Δ, the size can be reduced.
In general, Ge is used as a dopant for increasing the refractive index of the core, but a dopant capable of increasing the refractive index, such as Zr, may be used instead. As a result, the relative refractive index difference Δ between the core and the cladding can be increased to about 5% (2.5% to 12%), and the optical switch 131 can be further downsized.

  The waveguides of the eight optical splitters 181 included in the intersection splitter 180 intersect on a plane. FIG. 3A is a schematic diagram of a cross splitter 180 according to the present embodiment. In the cross splitter 180, the eight optical splitters 181 are arranged in parallel. Each optical splitter 181 is a 1 × 4 optical splitter, and has one common port 181a at one end and four branch ports 181b at the other end. In the crossing splitter 180, the waveguides of the eight optical splitters 181 intersect so that the arrangement order of the waveguides of the common port 181a and the arrangement order of the waveguides of the branch port 181b coincide. Specifically, as shown in FIG. 3A, common ports 181a (total 8) of the eight optical splitters 181 are arranged in the order of 1ch to 8ch, and branch ports 181b (total 32) of the eight optical splitters 181. 4) are arranged in the order of 1ch to 8ch.

  In order to arrange the branched waveguides in this order, the optical splitter 181 has two intersections A at which the waveguides intersect each other. In the crossing portion A, a loss (referred to as crossing loss) occurs when the waveguides cross each other. In the present embodiment, the cross splitter 180 is manufactured using, for example, a PLC formed on a quartz substrate, and the relative refractive index difference Δ between the core and the clad is about 0.4% (0.3% to 0.00). 5%). By using such a low relative refractive index difference Δ, the waveguide crossing loss can be reduced. In the present embodiment, although the number of times of crossing varies depending on the waveguide, the crossing loss is about 0.2 dB in the waveguide where the largest number of crossings (14 times) occurs. The intersection loss increases as the number of intersections increases (that is, as the number of intersections A increases), and decreases as the number of intersections decreases.

  The switch unit 130 is formed by fixing the end face of the substrate on which the cross splitter 180 is provided and the end face of the substrate on which the optical switch 131 is provided using an adhesive or the like. As a result, the branch ports 181b that are continuously arranged in the order of 1ch to 8ch at one end of the cross splitter 180 are connected to the 8 branch ports 131b of the optical switch 131, respectively.

  In this embodiment, the cross splitter 180 is provided on a substrate different from that of the optical switch 131. However, the cross splitter 180 is formed on the substrate on which the optical switch 131 is provided, and the relative refractive index difference between the core and the clad. Δ may be about Δ1.5%. In this case, the cross loss of the waveguide increases, but the size of the cross splitter 180 can be reduced, and the connection between the substrate on which the optical switch 131 is provided and the substrate on which the cross splitter 180 is provided is provided. Loss of part can be eliminated.

  With the above configuration, each channel of the ROADM network is divided by the optical splitter 121 connected to the channel, rearranged by the shuffle fiber array 170, and further divided and crossed by the crossing splitter 180. The switch 131 is connected to the branch port 131b corresponding to the channel. The branching operation of the switch device 100 will be specifically described below. When an optical signal is input to a common port 121a of the optical splitter 121 from a certain route (for example, 1ch) in the ROADM network, the optical signal is divided into four branch ports 121b of the optical splitter 121. The divided optical signals are input to different optical fibers 173 via the splitter-side fiber array 171 and further input to different switch units 130 via the switch-side fiber array 172. Thereafter, the divided optical signals are further divided into four (total 16 divisions) and crossed by the crossing splitter 180 of each switch unit 130, and are input to branch ports 131 b of different optical switches 131. The optical switch 131 is controlled by a control device so that the optical signal is transmitted in each optical switch 131 when it is to be output to a client device connected to the common port 131a and is extinguished otherwise. Is done.

  Next, the insertion operation of the switch device 100 will be specifically described. When an optical signal is input from a client device to the common port 131a of the optical switch 131, the optical signal is output to the branch port 131b corresponding to a predetermined channel (for example, 1ch) on which the client device should perform an insertion operation. As described above, the optical switch 131 is controlled by a control device. The optical signal is output from the branch port 131b of the optical switch 131, and sequentially passes through the crossing splitter 180, the switch side fiber array 172, the optical fiber 173, and the splitter side 171, and the branch port 121b of the optical splitter 121 corresponding to 1ch. Is input. Thereafter, the optical signal is inserted into the route of the ROADM network connected to the common port 121a of the optical splitter 121.

  The configuration of the crossing splitter 180 is not limited to that shown in FIG. 3A. For example, FIG. 3B is a schematic diagram of a cross splitter 180 that has fewer branches than FIG. 3A. The 16 optical splitters 181 included in the crossing splitter 180 of FIG. 3B are 1 × 2 optical splitters, respectively, and branch one common port 181a into two branch ports 181b. In the crossing splitter 180 of FIG. 3B, the crossing part A is provided in one place. In this case, if the number of paths and the number of wavelengths are the same, it is necessary to increase the number of branches of the optical splitter 121 included in the splitter unit 120 as much as the number of branches in the cross splitter 180 is smaller than in FIG. 3A. Therefore, it is necessary to increase the number of optical fibers 173 included in the shuffle fiber array, and the manufacturing cost of the shuffle fiber array 170 increases. On the other hand, since the number of crossings in the cross splitter 180 is reduced to a maximum of 7, the maximum cross loss can be reduced to about 0.1 dB. Conversely, when the cross splitter 180 having a larger number of branches than in FIGS. 3A and 3B is used, the number of crosses in the cross splitter 180 increases, so that the cross loss increases. However, the optical fiber 173 included in the shuffle fiber array 170 The number can be reduced, and the manufacturing cost of the shuffle fiber array 170 is reduced. Therefore, it is only necessary to select the cross splitter 180 having a desired number of branches in consideration of loss, manufacturing cost, and the like, and to change the number of branches of the optical splitter 121 accordingly.

  In the switch device 100 according to the present embodiment, the rearranged order of the branched channels is shared by the optical fiber 173 and the cross splitter 180. With such a configuration, the number of optical fibers 173 included in the shuffle fiber array 170 can be reduced as compared with the case where the order of channels is changed only by rearranging the shuffle fiber array 170. Therefore, the recombination work of the optical fiber 173 between the fiber arrays 171 and 172 can be facilitated, and the manufacturing cost of the shuffle fiber array 170 can be reduced. Further, since the number of optical fibers 173 included in the shuffle fiber array 170 is small, it is easy to handle the switch device 100, and the size of the switch device 100 can be reduced. In the cross splitter 180, the waveguides cross each other, so that a cross loss occurs. However, in the present embodiment, the maximum is about 0.2 dB, which is not a problem in practical use.

  In addition, when the rearrangement is performed only with the shuffle fiber array 970 as in the switch device 900 of FIG. 11, the number of branches of the optical splitter of the splitter unit 920 is unique depending on the predetermined number of paths and the number of wavelengths corresponding to the switch device 900. To be determined. On the other hand, in the switch device 100 according to the present embodiment, the number of paths and the number of wavelengths to which the switch device 100 corresponds are determined based on the number of branches of the optical splitter 121 of the splitter unit 120 and the number of branches of the optical splitter 181 of the cross splitter 180. It is possible to change freely within the range that satisfies. Therefore, the manufacturing cost of the shuffle fiber array 170 and the crossing loss of the crossing splitter 180 can be adjusted as desired.

(Second Embodiment)
FIG. 4 is a schematic diagram showing a wiring system of the switch device 200 according to the present embodiment. Since this embodiment has the same basic configuration as that of the first embodiment, the same reference numerals as those of the first embodiment are used. The switch device 200 differs from the first embodiment in the number of switch units 130 and the number of optical switches 131 per chip of the switch unit 130 (referred to as the number of arrays). The switch device 200 according to the present embodiment includes one splitter unit 120 and two switch units 130. The splitter unit 120 and the switch unit 130 are connected by a shuffle fiber array 170 having a plurality of optical fibers 173 that are three-dimensionally rearranged and fiber arrays 171 and 172 formed at both ends of the optical fibers.

  The splitter unit 120 includes eight optical splitters 121 on one chip (substrate). The optical splitter 121 used in this embodiment is a 1 × 2 optical splitter, and has one common port 121a at one end and two branch ports 121b at the other end.

  Each switch unit 130 includes eight optical switches 131 and a cross splitter 180 including eight optical splitters 181. The optical switch 131 is a 1 × 8 optical switch, and has one common port 131a at one end and eight branch ports 131b at the other end.

  The waveguides of the eight optical splitters 181 included in the intersection splitter 180 intersect on a plane. FIG. 5A is a schematic diagram of a cross splitter 180 according to the present embodiment. In the cross splitter 180, the eight optical splitters 181 are arranged in parallel. Each optical splitter 181 is a 1 × 8 optical splitter, and has one common port 181a at one end and eight branch ports 181b at the other end. In the crossing splitter 180, the waveguides of the eight optical splitters 181 are crossed so that the arrangement order of the common ports 181a and the arrangement order of the branch ports 181b coincide. That is, the common ports 181a (total 8) of the eight optical splitters 181 are arranged in the order of 1ch to 8ch, and the branch ports 181b (total 64) of the eight optical splitters 181 are 8 sets in the order of 1ch to 8ch. Are lined up. The crossing splitter 180 according to the present embodiment has three crossing portions A, and the crossing loss of the waveguide where the crossing occurs most frequently (21 times) is about 0.3 dB.

  With the above configuration, as in the first embodiment, each channel of the ROADM network is divided by the optical splitter 121 corresponding to the channel, rearranged by the shuffle fiber array 170, and further divided by the cross splitter 180. And after being crossed, each optical switch 131 is connected to a branch port 131b corresponding to the channel.

  The configuration of the crossing splitter 180 according to the present embodiment is not limited to that shown in FIG. 5A. For example, FIGS. 5B and 5C are schematic diagrams of a cross splitter 180 that has fewer branches than FIG. 5A. Each of the 16 optical splitters 181 included in the cross splitter 180 of FIG. 5B is a 1 × 4 optical splitter, and branches one common port 181a into four branch ports 181b. In the crossing splitter 180 of FIG. 5B, the crossing part A is provided in two places. Each of the 32 optical splitters 181 included in the cross splitter 180 of FIG. 5C is a 1 × 2 optical splitter, and branches one common port 181a into two branch ports 181b. In the crossing splitter 180 of FIG. 5C, the crossing portion A is provided at one place. In the case of FIGS. 5B and 5C, if the number of paths and the number of wavelengths are the same, the number of branches of the optical splitter 121 included in the splitter unit 120 needs to be increased as much as the number of branches in the cross splitter 180 is reduced compared to FIG. 5A. There is. Therefore, it is necessary to increase the number of optical fibers 173 included in the shuffle fiber array 170, and the manufacturing cost of the shuffle fiber array 170 increases. On the other hand, since the number of crossings in the cross splitter 180 is reduced to a maximum of 14 times in FIG. 5B and a maximum of 7 times in FIG. 5C, the maximum cross loss can be reduced to about 0.2 dB and 0.1 dB, respectively. On the other hand, when the cross splitter 180 having a larger number of branches than in FIGS. 5A to 5C is used, the cross loss increases because the number of crosses in the cross splitter 180 increases. However, the optical fiber 173 included in the shuffle fiber array 170 The number can be reduced, and the manufacturing cost of the shuffle fiber array 170 is reduced. Therefore, it is only necessary to select the cross splitter 180 having a desired number of branches in consideration of loss, manufacturing cost, and the like, and to change the number of branches of the optical splitter 121 accordingly.

  Also in the switch device 200 according to the present embodiment, the number of optical fibers 173 included in the shuffle fiber array 170 can be reduced and the number of branches of the optical splitter 121 of the splitter unit 120 can be reduced as in the first embodiment. The number of branches of the optical splitter 181 of the crossing splitter 180 can be freely changed within a range that satisfies a predetermined number of paths and wavelengths.

  In the first and second embodiments, the switch unit 130 has a configuration in which four optical switches 131 are provided on one chip, and a configuration in which eight optical switches 131 are provided on one chip. Although shown, the present invention is not limited to these chip configurations. All the optical switches 131 may be provided on a single chip, or the optical switches 131 may be provided separately on any number of two or more chips. Further, a different number of optical switches 131 may be provided on each chip. It is necessary to change the number of branches of the optical splitter 181 included in the crossing splitter 180 according to the number of optical switches 131 on one chip. Similarly, the optical splitter 121 of the splitter unit 120 may be provided on a single chip, or may be provided separately on any number of two or more chips.

(Third embodiment)
In the first and second embodiments, since the waveguides are not crossed in the splitter unit 120, the channels in the splitter-side fiber array 171 are not continuously arranged in the order of 1ch to 8ch. That is, they are arranged in a staircase pattern such as 1ch, 1ch, ~ 8ch, 8ch. Then, by rearranging the optical fibers 173 one by one in the shuffle fiber array 170, the channels in the switch side fiber array 172 are continuously arranged in the order of 1ch to 8ch. Therefore, in the first and second embodiments, when the optical fibers 173 are covered by 8 cores each, that is, when a tape is formed into a general tape core wire (also referred to as an 8-core tape), the splitter side fiber array 171 side The channel that should be included in one tape core differs from the switch side fiber array 172 side. Therefore, it is necessary to separate the tape cores on the splitter-side fiber array 171 side and rearrange them, and then re-tape them on the switch-side fiber array 172 side. On the other hand, the present embodiment has a configuration that eliminates the need for re-tapeing that separates and reassembles the tape cores, so that the manufacturing cost in the case of using the tape cores for the shuffle fiber array can be reduced.

  FIG. 6 is a schematic diagram illustrating a wiring method of the switch device 300 according to the present embodiment. The switch device 300 differs from the first and second embodiments in that not only the switch unit but also the waveguides included in the optical splitter provided in the splitter unit intersect with each other to form a cross splitter. That is. The switch device 300 includes one splitter unit 320 and four switch units 330. Each of the splitter unit 320 and the switch unit 330 is formed at eight ends of the tape core wires 374a and 374b formed by covering eight (eight cores) optical fibers with resin or the like. Are connected by a shuffle fiber array 370 having fiber arrays 371 and 372.

  The splitter unit 320 includes cross splitters 390a and 390b each including four optical splitters 391 on one chip (substrate). The waveguides of the four optical splitters 391 included in the crossing splitters 390a and 390b cross each other on a plane. FIG. 7 is a schematic diagram of the cross splitters 390a and 390b according to the present embodiment. In each of the cross splitters 390a and 390b, the four optical splitters 391 are arranged in parallel. Each optical splitter 391 is a 1 × 8 optical splitter, and has one common port 391a at one end and eight branch ports 391b at the other end.

  The common port 391a is arranged so that every other channel is arranged. That is, as shown in FIG. 7, the common ports 391a (total 4) of the first cross splitter 390a are arranged in the order of 1ch, 3ch, 5ch, and 7ch, and the common ports 391a (total) of the second cross splitter 390b. 4) are arranged in the order of 2ch, 4ch, 6ch, 8ch. Further, the waveguides of the four optical splitters 391 are crossed so that the same channel forms a pair in the branch ports 391b of the cross splitters 390a and 390b and the common ports 391a are arranged in the order. That is, as shown in FIG. 7, four sets of branch ports 391b (total 32) of the first cross splitter 390a are arranged in the order of 1ch, 1ch, 3ch, 3ch, 5ch, 5ch, 7ch, 7ch, The four branch ports 391b (total 32) of the cross splitter 390b are arranged in the order of 2ch, 2ch, 4ch, 4ch, 6ch, 6ch, 8ch, and 8ch. In each of the crossing splitters 390a and 390b, there are two crossing portions A, and the crossing loss is less than about 0.1 dB in the waveguide where the crossing occurs most frequently (six times). In the intersection splitters 390a and 390b according to the present embodiment, no intersection occurs between 1ch, 3ch, 5ch, and 7ch and 2ch, 4ch, 6ch, and 8ch. Therefore, compared with the cross splitter 180 described in FIGS. 3A and 3B and FIGS. 5A to 5C, the number of crossings is reduced even with the same number of branches, so that cross loss can be reduced.

  Since the branch ports 391b of the cross splitters 390a and 390b are arranged so that adjacent channels form a pair, the tape core wires 374a and 374b can be easily connected. Here, among the tape cores 374a and 374b, the one connected to the first cross splitter 390a is the first tape core 374a, and the one connected to the second cross splitter 390b is the second tape core. Line 374b. FIG. 8A is a diagram for explaining a connection state between the splitter-side fiber array 371 and the first tape core wire 374a. In FIG. 8A, only the connection portion of the first tape core wire 374a is shown for simplification, but the connection portion of the second tape core wire 374b is the same except that the channel number is different.

  As shown in FIG. 8A, the two first tape cores 374a are stacked in the thickness direction, and a plurality of optical fibers 373 included therein are fixed inside the splitter-side fiber array 371. At this time, the optical fibers 373 of the upper first tape core wire 374a and the optical fibers 373 of the lower first tape core wire 374a are alternately arranged in a line inside the splitter-side fiber array 371. . When the splitter-side fiber array 371 having such a configuration is connected to the first cross splitter 390a, two first tape cores 374a are formed in the first cross splitter 390a. Are alternately distributed and connected. As a result, the channels included in the two first tape cores 374a are the same, and the optical fibers 373 included in the first tape core 374a are arranged in the same order as the common port 391a of the first cross splitter 390a. It will be. Specifically, two sets of optical fibers 373 of the first tape core wire 374a are arranged in the order of 1ch, 3ch, 5ch, and 7ch. Similarly, the optical fibers 373 of the second tape core wire 374b are connected to the second cross splitter 390b, and two sets are arranged in the order of 2ch, 4ch, 6ch, and 8ch.

  The eight tape cores 374a and 374b are three-dimensionally rearranged between the splitter-side fiber array 371 and the switch-side fiber array 372, and each of the four switch-side fiber arrays 372 has a first tape core 374a. Are connected to the second tape core wire 374b. FIG. 8B is a diagram for explaining a connection state between the switch-side fiber array 372 and the tape core wires 374a and 374b. As shown in FIG. 8B, the first tape core 374a and the second tape core 374b are stacked in the thickness direction, and a plurality of optical fibers 373 included therein are fixed inside the switch side fiber array 372. Has been. At this time, the optical fibers 373 of the first tape core wires 374a and the optical fibers 373 of the second tape core wires 374b are alternately arranged in a line inside the switch-side fiber array 372. As a result, two sets of optical fibers 373 in the switch-side fiber array 372 are arranged in the order of 1ch to 8ch.

  Each switch unit 330 includes four optical switches 331 and a cross splitter 380 including 16 optical splitters 381. The optical switch 331 is a 1 × 8 optical switch, and has one common port 331a at one end and eight branch ports 331b at the other end.

  The eight optical splitters 381 included in the crossing splitter 380 are 1 × 2 optical splitters, and have one common port 381a at one end and two branch ports 381b at the other end. Similar to the configuration of FIG. 3B according to the first embodiment, in the crossing splitter 380, the waveguides of the 16 optical splitters 381 are arranged so that the arrangement order of the common ports 381a and the arrangement order of the branch ports 381b match. Crossed. That is, two sets of common ports 381a (16 in total) of 16 optical splitters 381 are arranged in the order of 1ch to 8ch, and branch ports 381b (16 in total) of 16 optical splitters 381 are in the order of 1ch to 8ch. There are 4 groups. The crossing splitter 380 according to the present embodiment has the crossing portion A at one place, and the crossing loss of the waveguide where the crossing occurs most frequently (seven times) is about 0.1 dB.

  The switch unit 330 is formed by fixing the end surface of the substrate on which the cross splitter 380 is provided and the end surface of the substrate on which the optical switch 331 is provided using an adhesive or the like. As a result, the branch ports 381b arranged in the order of 1ch to 8ch at one end of the cross splitter 380 are connected to the 8 branch ports 331b of the optical switch 331, respectively. Further, the crossing splitter 380 and the optical switch 331 may be provided on the same substrate.

  According to this embodiment, even if the tape cores (optical fibers) are divided between the splitter-side fiber array 371 and the switch-side fiber array 372, the tape cores can be easily fused. Connection can be made. That is, when the splitter-side tape core wire extends from the splitter-side fiber array 371 and the switch-side tape core wire extends from the switch-side fiber array 372, the order of channels in the splitter-side tape core wire and the switch-side tape Since the arrangement order of the channels in the cores is the same, there is no need to rearrange and re-tape the optical fibers, and the end faces of the corresponding tape cores can be simply put together to perform the fusion work.

  Thus, in this embodiment, two types of crossing splitters 390a and 390b for branching and crossing different channels are provided in the splitter unit 320, and the splitter unit is configured using the two types of tape cores 374a and 374b corresponding to each. 320 and the switch unit 330 are connected. Therefore, the channels can be arranged in a continuous order without re-tapeing the tape core wire connecting the splitter unit 320 and the switch unit 330, so that the manufacturing cost of the shuffle fiber array 370 can be reduced.

(Fourth embodiment)
In the first and second embodiments, the cross splitter is provided only in the switch unit, and in the third embodiment, the cross splitter is provided in both the splitter unit and the switch unit. On the other hand, in this embodiment, the crossing splitter is provided only in the splitter unit. FIG. 9 is a schematic diagram showing a wiring system of the switch device 400 according to the present embodiment. Since this embodiment has the same basic configuration as that of the third embodiment, the same reference numerals as those of the third embodiment are used. In the switch device 400, the cross splitter 380 of the switch unit 330 is omitted from the third embodiment, and the number of branches of the optical switch 331 and the optical splitter 391 is changed accordingly.

  In the present embodiment, unlike the third embodiment, since the switch unit 330 is not provided with an optical splitter, the number of branches of the optical splitter 391 in the splitter unit 320 is increased accordingly. Specifically, the optical splitter 391 is a 1 × 16 optical splitter, and has one common port 391a at one end and 16 branch ports 391b at the other end. Although the function of the splitter unit 320 is not affected, the first cross splitter 390a and the second cross splitter 390b are provided separately on different substrates (chips), and the splitter side fiber array 371 is provided. Is also divided so as to be connected to each substrate of the splitter unit 320. The number of chip divisions is not limited to this form, and may be set arbitrarily.

  Similarly to the third embodiment, the splitter unit 320 and the switch unit 330 are connected via the splitter-side fiber array 371, the first tape core wire 374a, the second tape core wire 374b, and the switch-side fiber array 372. ing. The optical fibers 373 in the splitter-side fiber array 371 are arranged so that every other channel is provided, and the optical fibers 373 in the switch-side fiber array 372 are arranged successively in the order of 1ch to 8ch. By connecting the switch-side fiber array 372 to the end face of the switch unit 330, the optical fibers 373 arranged in the order of 1ch to 8ch in the switch-side fiber array 372 are connected to the eight branch ports 331b of the optical switch 331, respectively. .

  Even when the cross splitters 390a and 390b are provided only in the splitter unit 320 as in the present embodiment, the channels are arranged in a continuous order without re-tapeing the tape core wires, as in the third embodiment. Therefore, the manufacturing cost of the shuffle fiber array 370 can be reduced.

(Fifth embodiment)
In the cross splitter 180 shown in FIGS. 3A and 3B and FIGS. 5A to 5C, the order of the channels is rearranged by crossing the waveguides on the plane at the cross portion A. FIG. 10A is an enlarged view of the intersection A of the intersection splitter 180. At the intersection A, the waveguides intersect at an angle of 60 to 90 degrees, and this point is defined as an intersection B. Although a cross loss occurs at the intersection B, the cross loss differs because the number of crossings (the number of the cross points B) is different for each waveguide included in the cross splitter 180. For example, in FIG. 3A, the maximum number of crossings is 14 (cross loss about 0.2 dB), and the minimum is 0 (cross loss 0 dB). In the present embodiment, the average cross loss between the waveguides can be averaged to reduce the maximum cross loss of the cross splitter.

  FIG. 10B is an enlarged view of the intersection A of the intersection splitter according to the present embodiment. At the intersection A, one of the two waveguides to be intersected is interrupted, and the fracture surface of the waveguide is disposed so as to sandwich the other waveguide. This portion is referred to as a fracture portion C. In the fracture portion C, an optical signal passes between fractured surfaces of the waveguides that are interrupted, and cross loss occurs at that time. On the other hand, in an unbroken waveguide, an optical signal passes without generating a crossing loss, so that it can be regarded as not crossing. That is, at the intersection A, since only one of the two waveguides to be intersected can be in an intersecting state, the number of intersections and the intersection loss can be reduced as a whole.

  In the present embodiment, at the intersection A of the intersection splitter 180 shown in FIGS. 3A and 3B and FIGS. 5A to 5C, the fracture portion C is formed at least at a part of the intersection B of the waveguide having a large number of intersections. Is an unbroken waveguide. In other words, the fracture portion C is formed at least at a part of the intersection B where the waveguides having different numbers of crossings intersect, and the waveguide having the higher number of crossings is set as an unbroken waveguide, and the waveguide having the lower number of crossings is selected. The waveguide is interrupted. Thereby, the number of crossings and the crossing loss of the entire crossing splitter 180 can be averaged, and the maximum crossing loss can be reduced. It is desirable to provide the breaking portion C so that the maximum number of crossings as the entire crossing splitter 180 is reduced. The cross splitter according to this embodiment can be used for any of the cross splitters of the first to fourth embodiments described above.

The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the spirit of the present invention. For example, in each of the above-described embodiments, the configuration of an exemplary switch device in which the number of routes is 8 and the number of wavelengths is 16, an optical signal is obtained by using a shuffle fiber array and a cross splitter in cooperation. The number of paths and the number of wavelengths can be arbitrarily determined as long as the channels can be branched to the desired number of branches and rearranged in the desired order. Depending on the number of wavelengths and the number of paths that the switch device should support, the configuration of the optical splitter, crossing splitter, and optical switch is determined, mounted on one or more chips, and connected via a shuffle fiber array. Good.

Claims (8)

A switch device for branching and inserting optical signals,
A splitter for splitting and merging the optical signals;
A switch unit for performing path selection of the optical signal;
A plurality of optical fibers connecting the splitter unit and the switch unit;
An intersection that is provided in at least one of the splitter unit and the switch unit, has a plurality of optical splitters, and at least some of the waveguides included in the optical splitters intersect each other on a plane. A splitter,
A switch device comprising:   That at least some of the waveguides included in the plurality of optical splitters cross each other so that the arrangement order of the waveguides at one end of the cross splitter matches the arrangement order of the waveguides at the other end. The switch device according to claim 1.   The plurality of optical fibers are three-dimensionally rearranged so that the arrangement order of the plurality of optical fibers in the portion connected to the switch section matches the arrangement order of the branch ports of the optical switch included in the switch section. The switch device according to claim 2, wherein the switch device is provided. The first cross splitter and the second cross splitter are provided in the splitter section;
The first crossing splitter and the switch unit are connected by a first tape core wire formed by covering a part of the plurality of optical fibers,
The said 2nd crossing splitter and the said switch part are connected with the 2nd tape core wire formed by coat | covering another one part of these optical fibers. The switch device described.   A part of the branch port of the optical switch included in the switch unit is connected to the optical fiber included in the first tape core wire, and another part of the branch port of the optical switch included in the switch unit is the first part. The switch device according to claim 4, wherein the switch device is connected to an optical fiber included in the two tape core wires.   The switch device according to claim 1, wherein the waveguides intersect at an angle of 60 to 90 degrees at a portion where the waveguides intersect each other.   The switch device according to claim 1, wherein one of the waveguides is interrupted at a portion where the waveguides intersect each other. 8. The waveguide according to claim 7, wherein one of the waveguides is interrupted at a portion where the waveguides intersect each other so that the maximum number of times the waveguides included in the intersection splitter are reduced. The switch device described.

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