Optical signal processing device

Abstract

Provided is an optical signal processing device having low crosstalk. An optical signal processing device according to one embodiment of the present disclosure comprises: at least one first input-output waveguide; a wavelength demultiplexer that is connected to the first input-output waveguide; a plurality of wavelength multiplexers; at least one second input-output waveguide that is connected to each of the plurality of wavelength multiplexers; and a connection circuit that connects the wavelength demultiplexer and the plurality of wavelength multiplexers. The connection circuit includes a plurality of waveguides. One end of each of the plurality of waveguides in the connection circuit is connected to the wavelength demultiplexer. The other ends of the plurality of waveguides in the connection circuit are divided into a plurality of subsets. The other end of one or a plurality of adjacent waveguides in a kth (k is the integer 2) subset among the plurality of subsets is connected to the kth wavelength multiplexer among the plurality of wavelength multiplexers.

Description

[Technical Field]

[0001] This disclosure relates to an optical signal processing apparatus, and more specifically to an optical signal processing apparatus having a plurality of array waveguide diffraction gratings. [Background technology]

[0002] With the increasing capacity of wavelength division multiplexing optical communication, research and development on optical waveguide devices such as optical wavelength multiplexing / demultiplexing circuits and optical switch circuits that support this are actively being conducted. Optical wavelength multiplexing / demultiplexing circuits are used for multiplexing and demultiplexing optical signals, and narrowing the guard bandwidth, which determines the multiplexing / demultiplexing performance, is an important issue that determines the performance of optical communication.

[0003] A high-performance optical wavelength multiplexing and demultiplexing circuit (hereinafter also referred to as "tandem AWG") is known, which consists of two arrayed waveguide gratings (AWGs) connected in cascade (see, for example, Non-Patent Document 1). Tandem AWGs have the advantage of having a narrow guard band, that is, a highly rectangular transmission spectral characteristic.

[0004] A tandem AWG has the function of transmitting light of a desired wavelength to any output of the second AWG by sampling the wavelength of light at narrow intervals in the first AWG and adjusting the input position of the second AWG. Therefore, a tandem AWG is effective as an optical wavelength demultiplexer filter with a narrow guard bandwidth and highly rectangular transmission spectral characteristics. Based on the principle of ray back propagation, a tandem AWG is also effective as an optical wavelength multiplexer filter. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] Christopher Richard Doerr, M. Cappuzzo, L. Gomez, E. Chen, A. Wong-Foy, C. Ho, J. Lam, and K. McGreer, "Planar Lightwave Circuit Eight-Channel CWDM Multiplexer With < 3.9-dB Insertion Loss," J. Lightwave Technol. 23, 62- (2005) [Overview of the project]

[0006] In a tandem AWG, the first AWG and the second AWG must be connected by a connecting circuit. To prevent degradation of interference characteristics, the phase difference of the optical waves must be maintained until the optical signal propagates from the output of the first AWG to the input of the second AWG through the connecting circuit.

[0007] The first AWG and the second AWG each include an array waveguide composed of multiple waveguides having different optical path lengths. The connecting circuit between the first AWG and the second AWG also consists of multiple waveguides. In a tandem AWG comprising the first AWG, the second AWG, and the connecting circuit, each composed of multiple waveguides, there are numerous optical paths with different path lengths between the input of the first AWG and the output of the second AWG. Phase errors of the optical waves occurring in the first AWG, the second AWG, and the connecting circuit degrade the interference characteristics in each of them. This degradation of interference characteristics increases crosstalk noise, which is one of the optical characteristics of an optical wavelength multiplexing / demultiplexing circuit, and leads to a deterioration in the transmission quality of the optical signal.

[0008] This disclosure has been made in view of such problems and aims to provide an optical signal processing device with low crosstalk noise.

[0009] To achieve this objective, an optical signal processing apparatus according to one embodiment of the present disclosure comprises at least one first input / output waveguide, a wavelength demultiplexer connected to the first input / output waveguide, a plurality of wavelength multiplexers, at least one second input / output waveguide connected to each of the plurality of wavelength multiplexers, and a connecting circuit connecting the wavelength demultiplexer and the plurality of wavelength multiplexers, wherein the connecting circuit includes a plurality of waveguides, one end of the plurality of waveguides in the connecting circuit is connected to the wavelength demultiplexer, the other end of the plurality of waveguides in the connecting circuit is divided into a plurality of subsets, and the other end of one of the k-th subset (where k is an integer of 2) or an adjacent plurality of waveguides is connected to the k-th wavelength multiplexer among the plurality of wavelength multiplexers.

[0010] As described above, according to one embodiment of the present disclosure, by connecting a plurality of wavelength multiplexers in parallel with a wavelength demultiplexer via a connecting circuit, it is possible to provide an optical wavelength multiplexing and demultiplexing circuit with low crosstalk noise values. [Brief explanation of the drawing]

[0011] [Figure 1] This is a schematic diagram showing a tandem AWG. [Figure 2] This is a schematic diagram showing an optical signal processing apparatus according to one embodiment of the present disclosure, where (a) is a diagram showing the overall configuration, (b) is a diagram showing the configuration of a wavelength demultiplexer, and (c) is a diagram showing the configuration of a wavelength multiplexer. [Figure 3] This figure illustrates the light input to a wavelength demultiplexer of an optical signal processing device according to one embodiment of the present disclosure. [Figure 4] This figure illustrates light propagating through a wavelength demultiplexer of an optical signal processing device according to one embodiment of the present disclosure. [Figure 5] This figure illustrates light propagating through a wavelength demultiplexer of an optical signal processing device according to one embodiment of the present disclosure. [Figure 6] This figure illustrates the light input to a wavelength multiplexer of an optical signal processing device according to one embodiment of the present disclosure. [Figure 7]This figure illustrates the light input to a wavelength multiplexer of an optical signal processing device according to one embodiment of the present disclosure, where (a) is a figure illustrating the light input to the wavelength multiplexer, and (b) is a figure illustrating the transmission characteristics of the wavelength multiplexer. [Figure 8] This is a schematic diagram showing a modified form of an optical signal processing device according to one embodiment of the present disclosure, where (a) is a diagram showing the overall configuration, (b) is a diagram showing the configuration of a wavelength demultiplexer, and (c) is a diagram showing the configuration of a wavelength multiplexer. [Modes for carrying out the invention]

[0012] Hereinafter, optical signal processing apparatuses according to various embodiments of the present disclosure will be described with reference to the drawings. The same or similar reference numerals indicate the same or similar elements, and repeated descriptions may be omitted. The numerical values ​​and materials in the following description are illustrative, and optical signal processing apparatuses according to embodiments of the present disclosure can be implemented by substituting other numerical values ​​and materials without departing from the spirit of the present disclosure. Prior to describing the optical signal processing apparatus according to the embodiments of this disclosure, a tandem AWG will be described.

[0013] (Tandem AWG) Figure 1 is a schematic diagram showing the general configuration of a tandem AWG. As shown in Figure 1, the tandem AWG 100 comprises a first AWG 110, a second AWG 120, one input waveguide 111 connected to the input of the first AWG 110, two output waveguides 121-1 and 121-2 connected to the output of the second AWG 120, and a connection circuit 130 connecting the output of the first AWG 110 and the input of the second AWG 120. The tandem AWG 100 is configured to wavelength demultiplex a signal input via the input waveguide 111 and output the optical signal of wavelength λ1 and the optical signal of wavelength λ2 included in the wavelength division multiplexed signal from the two output waveguides 121-1 and 121-2, respectively.

[0014] In the tandem AWG 100, the first AWG 110 is configured such that a wavelength-division multiplexed signal (an optical signal with wavelength λ1 and an optical signal with wavelength λ2) input via the input waveguide 111 is demultiplexed to different positions of the first AWG 110 according to the wavelength.

[0015] The second AWG 120 is configured such that optical signals with the same wavelength among the input plurality of wavelengths are multiplexed to different positions of the second AWG 120 according to the wavelength.

[0016] One ends of the plurality of waveguides constituting the connection circuit 130 are connected to the positions where the optical signals with wavelength λ1 and wavelength λ2 of the first AWG 110 are demultiplexed. The other ends of the plurality of waveguides constituting the connection circuit 130 have a gap for separating the position where the optical signal with wavelength λ1 of the second AWG 120 is input and the position where the optical signal with wavelength λ2 of the second AWG 120 is input, and are connected to the second AWG 120.

[0017] The two output waveguides 121-1 and 121-2 are respectively connected to the positions where the light of the second AWG 120 is multiplexed.

[0018] In the tandem AWG100 shown in Figure 1, the optical signals of wavelength λ1 and wavelength λ2 are separated and sent to different positions in the first AWG110. The optical signal of wavelength λ1 is separated to the upper position of the first AWG110 and coupled to the waveguide connected to the first AWG110 at that position among the multiple waveguides constituting the connection circuit 130, and propagates to the second AWG120. The optical signal of wavelength λ2 is separated to the lower position of the first AWG110 and coupled to the waveguide connected to the first AWG110 at that position among the multiple waveguides constituting the connection circuit 130, and propagates to the second AWG120. The optical signals of wavelength λ1 and wavelength λ2, input to different positions in the second AWG120, are combined and sent to different positions in the second AWG120. The optical signals of wavelength λ1 are combined at the upper position of the second AWG120 and coupled to output waveguide 121-1 connected to the second AWG120 at that position, and output. The optical signals of wavelength λ2 are combined at the lower position of the second AWG120 and coupled to output waveguide 121-2 connected to the second AWG120 at that position, and output.

[0019] The tandem AWG100 with the above configuration has the function of transmitting light of a desired wavelength to any position in the second AWG120 by sampling the wavelength of light at narrow intervals in the first AWG110 and adjusting the input position of the second AWG120.

[0020] The gap in the waveguide constituting the connection circuit 130 at the connection point with the second AWG120 corresponds to the guard band. The higher the resolution of the wavelength demultiplexing function of the first AWG110, the smaller the gap can be, i.e., the guard band can be reduced. In tandem AWG100, increasing the resolution of the first AWG110 makes it possible to achieve a highly rectangular transmission spectral characteristic with a narrow guard band width. On the other hand, reducing the guard band is accompanied by an increase in crosstalk noise, which leads to a deterioration in the transmission quality of the optical signal.

[0021] The following describes optical signal processing devices according to various embodiments of the present disclosure. An optical signal processing device according to one embodiment of the present disclosure comprises a first AWG constituting a wavelength demultiplexer, a plurality of second AWGs constituting a plurality of wavelength multiplexers, and a connecting circuit connecting the wavelength demultiplexer and the plurality of wavelength multiplexers. The connecting circuit includes a plurality of waveguides. One end of the plurality of waveguides in the connecting circuit is connected to the output of the wavelength demultiplexer. The other end of the plurality of waveguides in the connecting circuit is divided into a plurality of subsets, and the other end of one of the k-th (k is an integer of 2) subsets or of an adjacent plurality of waveguides is connected to the input of the k-th wavelength multiplexer among the plurality of wavelength multiplexers. According to one embodiment of the present disclosure, an optical signal processing device with low crosstalk noise is provided.

[0022] (First embodiment) The optical signal processing device according to the first embodiment will be described with reference to Figure 2. Figure 2(a) is a diagram showing the overall configuration of the optical signal processing device 200. As shown in Figure 2(a), the optical signal processing device 200 includes a first AWG 210 which constitutes a wavelength demultiplexer, two second AWGs 220-1 and 220-1 which constitute two wavelength multiplexers, one input waveguide 111 connected to the input of the first AWG 110, an output waveguide 221-1 connected to the output of one of the second AWGs 120-1, an output waveguide 221-2 connected to the output of the other second AWG 120-2, and a connection circuit 230 which connects the output of the first AWG 110 to the inputs of the two second AWGs 220-1 and 220-2. The optical signal processing device 200, similar to the tandem AWG 100 shown in Figure 1, is configured to wavelength-demultiplex the wavelength-multiplexed signal input via the input waveguide 111, and to output the optical signal of wavelength λ1 and the optical signal of wavelength λ2 included in the wavelength-multiplexed signal from two output waveguides 221-1 and 221-2, respectively.

[0023] Furthermore, based on the principle of retro-propagation of light rays, the optical signal processing device 200 can also combine the input optical signal of wavelength λ1 and the optical signal of wavelength λ2 to output a wavelength-multiplexed signal. That is, the input waveguide 111 and the output waveguides 221-1 and 221-2 constitute the input and output waveguides, respectively. In addition, AWG210 and 220 constitute a wavelength multiplexer.

[0024] Figure 2(b) shows the configuration of the first AWG210 that constitutes the wavelength demultiplexer. As shown in Figure 2(b), the AWG210 comprises a first slab 210a, an array waveguide 210b, and a second slab 210c. The array waveguide 210b is composed of a plurality of waveguides having a waveguide length difference. The array waveguide 210b is connected to the output end of the first slab 210a and the input end of the second slab 210c. An input waveguide 111 is connected to the input end of the first slab 210a. A connection circuit 230 is connected to the output end of the second slab 210c.

[0025] Figure 2(c) shows the configuration of the second AWG220 (220-1 or 220-2) that constitutes the wavelength multiplexer. As shown in Figure 2(c), the AWG220 comprises a first slab 220a, an array waveguide 220b, and a second slab 220c. The array waveguide 220b is composed of multiple waveguides having a waveguide length difference. The array waveguide 220b is connected to the output end of the first slab 220a and the input end of the second slab 220c. A connection circuit 230 is connected to the input end of the first slab 220a. An output waveguide 221 is connected to the output end of the second slab 220c.

[0026] In the optical signal processing device 200, the first AWG210 is configured such that wavelength-division multiplexed signals (optical signals of wavelength λ1 and wavelength λ2) input via the input waveguide 111 are demultiplexed to different positions on the first AWG210 according to their wavelengths.

[0027] Each of the two second AWG220-1 and 220-2 is configured to combine light of the same wavelength that is input to them. The second AWG220 differs from the AWG120 in Figure 1, which inputs multiple light of different wavelengths and combines light of the same wavelength, in that it inputs and combines light of the same wavelength. The resonant frequency interval (free spectral range: FSR) of the second AWG220, which inputs and outputs light of one wavelength, can be made smaller than the FSR of the first AWG210 and the second AWG120 in Figure 1, which input and output light of multiple wavelengths.

[0028] The multiple waveguides constituting the connection circuit 230 are divided into two subsets. Each subset contains one or more adjacent waveguides. In Figure 2(a), the upper part of the connection circuit 230 is Subset 1, and the lower part is Subset 2. One end of the waveguide in Subset 1 is connected to the position where the optical signal with wavelength λ1 is demultiplied in the first AWG210 (the upper position on the output end face of the second slab 210c). One end of the waveguide in Subset 2 is connected to the position where the optical signal with wavelength λ2 is demultiplied in the first AWG210 (the lower position on the output end face of the second slab 210c). On the other hand, the other end of the waveguide in Subset 1 is connected to the second AWG220-1 (the input end face of the first slab 220a). The other end of the waveguide in Subset 2 is connected to the second AWG220-2 (the input end face of the first slab 220a).

[0029] In the optical signal processing device 200 shown in Figure 2, the optical signals of wavelength λ1 and wavelength λ2 are input to the first slab 210a of the first AWG 210 via the input waveguide 111. Figure 3 shows the intensity distribution of the optical signals at the boundary between the first slab 210a and the input waveguide 111. In Figure 3, the position of the first slab 210a to which the input waveguide 111 is connected is denoted as x0. The intensity distribution shown in Figure 3 is the intensity distribution of monochromatic light. If the wavelength division multiplexing signal input to the first AWG 210 via the input waveguide 111 includes optical signals of multiple wavelengths, each wavelength of optical signal will have an intensity distribution similar to that shown in Figure 3.

[0030] In the first AWG210, the optical signals of wavelength λ1 and wavelength λ2 propagate through the first slab 210a, spreading in directions perpendicular to the propagation axis. Figure 4 shows the intensity distribution of the optical signals at the boundary between the first slab 210a and the array waveguide 210b. The array waveguide 210b is connected to the position in the first slab 210a where the intensity of the optical signals shown in darker colors in Figure 4 appears.

[0031] In the first AWG210, multiple optical signals of wavelength λ1 input to the second slab 210c via multiple waveguides having a waveguide length difference that constitute the array waveguide 210b have different phases corresponding to the length of the waveguides through which they propagate. Similarly, multiple optical signals of wavelength λ2 input to the second slab 210c also have phases corresponding to the length of the waveguides through which they propagate. The optical signals of each wavelength input to the first AWG210 are combined at positions corresponding to their wavelengths. Specifically, the optical signals of wavelength λ1 interfere with each other and are combined, appearing at an upper position on the AWG210 (second slab 210c). The optical signals of wavelength λ2 interfere with each other and are combined, appearing at a lower position on the AWG210 (second slab 210c). One or more waveguides of subset 1 of the connection circuit 230 are connected at the positions where the optical signals of wavelength λ1 appear. Furthermore, one or more waveguides of subset 2 of connection circuit 230 are connected to the position where the optical signal with wavelength λ2 appears.

[0032] Figure 5 shows the transmission loss at the boundary between the first AWG210 and the second slab 210c and the connecting circuit 230. As shown in Figure 5, crosstalk noise is generated due to the phase error occurring in the first AWG210. Therefore, it is desirable to configure the connecting circuit 230 such that the waveguides constituting the connecting circuit 230 are not connected to positions where the crosstalk of the second slab 210c is high. As a result, the crosstalk occurring at the position between subset 1 and subset 2 of the connecting circuit 230 is reduced compared to when no subsets are provided.

[0033] Figure 6 shows the effective refractive index of the first AWG210 array waveguide 210b at 10 -5Assuming there is a degree of random variation, for any integer k (k=1,2), any one waveguide in subset k of the connection circuit 230 has λ k This is the optical signal intensity distribution of subset k of the connection circuit 230 when optical signals of different wavelengths are coupled. Each dashed line in Figure 6 corresponds to each waveguide included in subset k. As can be seen from Figure 6, the crosstalk noise within subset k of the connection circuit 230 is approximately -40 dB.

[0034] Figure 7(a) shows the input λ1(λ) to the second AWG220-2 when k=2. k=2 This is the intensity distribution of the optical signal (of a different wavelength). The peak intensity of the optical signal at λ1 is approximately -40 dB. Figure 7(b) shows the transmission loss at the boundary between the second slab 210c of the second AWG220-2 and the waveguide of subset 2 of the connecting circuit 230. It can be seen that the crosstalk of the connecting circuit 230 to subset 2 is less than -80 dB.

[0035] In this way, in the optical signal processing device 200, the optical signal of wavelength λ1 and the optical signal of wavelength λ2 are separated to different positions on the first AWG210 (second slab 210c). The optical signal of wavelength λ1 is separated to an upper position on the first AWG210 (second slab 210c), and is coupled to the waveguide of subset 1, which is connected to the first AWG210 at that position among the multiple waveguides constituting the connection circuit 230, and propagates to the second AWG220-1. The optical signal of wavelength λ2 is separated to a lower position on the first AWG210 (second slab 210c), and is coupled to the waveguide of subset 2, which is connected to the first AWG110 at that position among the multiple waveguides constituting the connection circuit 130, and propagates to the second AWG120.

[0036] The multiple waveguides constituting the connection circuit 230 are of equal length, or have an optical path length difference that is an integer multiple of the wavelength of the propagating optical signal. This preserves the phase difference of the optical waves and prevents deterioration of the interference characteristics in the first AGW. On the other hand, the spacing between adjacent waveguides constituting the connection circuit 230 may be constant or not. For example, when separating a wavelength λ1 in the C wavelength band and a wavelength λ2 in the L wavelength band from a wavelength-division multiplexed signal, the spacing between adjacent waveguides in subset 1 of the connection circuit 230 and the spacing between adjacent waveguides in subset 2 can be made different.

[0037] As described above, the first AWG210 has the function of splitting the input optical signal to different positions according to its wavelength, but at the same time, it also has the function of splitting the optical signal to different positions according to the input position of the optical signal. Changing the input position of the optical signal changes the wavelength of the optical signal that propagates through subsets 1 and 2 of the connection circuit 230 and is input to the second AWG220-1 and 220-2. Furthermore, changing the wavelength of the optical signal also changes the position at which it is combined in the second AWG220-1 and 220-2. Therefore, the optical signal processing device 200 may be configured in which multiple input waveguides are connected to the first AWG210 and multiple output waveguides are connected to each of the second AWG220-1 and 220-2.

[0038] The first AWG210, the connecting circuit 230, and the second AGW220 may be configured on the same Planar Lightwave Circuit (PLC), or the first AWG210 and the second AGW220, which are created separately, may be connected by the connecting circuit 230.

[0039] The material for the optical wave circuits constituting the first AWG210 and the second AGW220 in this embodiment can be silicon oxide (SiO2), which has low connection loss with the optical fiber. Alternatively, the material for the optical wave circuits may be silicon (Si), which allows for a smaller circuit area, or silicon nitride (Si3N4), which has performance intermediate between silicon oxide and silicon.

[0040] As described above, this embodiment provides an optical signal processing device 200 with low crosstalk noise. In this embodiment, an optical signal processing device 200 has been described that wavelength-multiplexed signal input via the input waveguide 111 is wavelength-demultiplexed and outputs two optical signals of wavelengths λ1 and λ2 included in the wavelength-multiplexed signal from two output waveguides 221-1 and 221-2, respectively. However, it is also possible to configure an optical signal processing device that outputs three or more optical signals of different wavelengths from the wavelength-multiplexed signal from three or more output waveguides, respectively.

[0041] (Transformation form 1) A modified form of the optical signal device of this embodiment will be described with reference to Figure 8. This modified form of optical signal device is configured to output three or more optical signals of different wavelengths from a wavelength-multiplexed signal from three or more output waveguides.

[0042] Figure 8(a) shows the overall configuration of the optical signal processing device 800. As shown in Figure 8(a), the optical signal processing device 800 comprises a first AWG810 that constitutes a wavelength demultiplexer, second AWG820-1, 820-2, ... 820-k that constitute k wavelength multiplexers (k is an integer of 3 or more), one input waveguide 111 connected to the input of the first AWG810, an output waveguide 821-k connected to the output of the kth second AWG820-k, and a connection circuit 830 that connects the output of the first AWG810 to each of the k second AWG820-1, 820-2, ... 820-k. Similar to the optical signal processing device 200 shown in Figure 2, the optical signal processing device 800 wavelength-demultiplexes the wavelength-multiplexed signal input via the input waveguide 111, and wavelengths λ1 to λ included in the wavelength-multiplexed signal k The optical signals are configured to be output from k output waveguides 221-1 to 221-k, respectively.

[0043] Furthermore, similar to the optical signal processing device 200, based on the principle of retro-propagation of light rays, the optical signal processing device 800 converts the input optical signal of wavelength λ1 to wavelength λ kIt is also possible to combine the optical signals and output wavelength-division multiplexed signals. Specifically, input waveguide 111 and output waveguides 821-1 to 821-k constitute input and output waveguides, respectively. In addition, AWG810 and 820-1 to 820-k constitute a wavelength multiplexer.

[0044] Figure 8(b) shows the configuration of the first AWG810 that constitutes the wavelength demultiplexer. Similar to the first AWG210 shown in Figure 2(b), the first AWG810 comprises a first slab 810a, an array waveguide 810b, and a second slab 810c. The array waveguide 810b is composed of multiple waveguides having a waveguide length difference. The array waveguide 810b is connected to the output terminal of the first slab 810a and the input terminal of the second slab 810c. The input waveguide 111 is connected to the input terminal of the first slab 810a. Subsets 1 to k of the connection circuit 830 are connected to the output terminal of the second slab 810c.

[0045] Figure 8(c) shows the configuration of the second AWG820 (820-1 to 820-k) that constitute the wavelength multiplexer. As shown in Figure 8(c), the AWG820 comprises a first slab 820a, an array waveguide 820b, and a second slab 820c. The array waveguide 820b is composed of multiple waveguides having a waveguide length difference. The array waveguide 820b is connected to the output terminal of the first slab 820a and the input terminal of the second slab 820c. A subset k of the connection circuit 830 is connected to the input terminal of the first slab 820a of the second AWG820-k. The output waveguide 221-k is connected to the output terminal of the second slab 810c of the second AWG820-k.

[0046] As described above, the first AWG 810 has a function of demultiplexing the input optical signal to different positions according to the wavelength, and at the same time, has a function of demultiplexing the optical signal to different positions according to the position where the optical signal is input. When the position where the optical signal is input is changed, the wavelength of the optical signal propagating from subset 1 to k of the connection circuit 830 and input to the second AWGs 820-1 to 820-k changes. Further, when the wavelength of the optical signal is changed, the position where the optical signals are multiplexed in the second AWGs 820-1 to 820-k also changes. Therefore, the optical signal processing apparatus 800 may be configured such that a plurality of input waveguides are connected to the first AWG 810 and a plurality of output waveguides are connected to each of the second AWGs 820-1 to 820-k.

[0047] The AWG 810, AWG 820, connection circuit 830, and output waveguide 821 in the optical signal processing apparatus 800 respectively correspond to the AWG 210, AWG 220, connection circuit 230, and output waveguide 221 in the above-described optical signal processing apparatus 200, and thus detailed description thereof is omitted.

[0048] As described above, according to this modified embodiment, an optical signal processing apparatus 200 with low crosstalk noise can be provided.

[0049] In the description of this modified embodiment, the wavelengths λ1 to λ k are extended to wavelength bands λ1 to λ k , and a plurality of wavelengths (wavelengths λ 1-1 , λ 1-2 , ···) included in the wavelength band λ1, a plurality of wavelengths (wavelengths λ 2-1 , λ 2-2 , ···) included in the wavelength band λ2, ··· a plurality of wavelengths (wavelengths λ k , λ k-1 , λ k-2 , ···) included in the wavelength band λ

[0050] As described above, according to this modified embodiment, an optical signal processing apparatus with low crosstalk noise can be provided.

Industrial Applicability

[0051] This provides an optical wavelength multiplexing and demultiplexing circuit with lower crosstalk noise values ​​than conventional configurations. [Explanation of Symbols]

[0052] 100 Tandem AWG 110, 120, 210, 220, 810, 820AWG 111 Input Waveguide 121, 221, 821 Output waveguides 130 connection circuit, 230, 830 connection circuit 200, 800 Optical signal processing equipment 210a, 210c, 220a, 220c, 810a, 810c, 820a, 820c slabs 210b, 220b, 810b, 820b array waveguides

Claims

1. An optical signal processing device, At least one first input / output waveguide, A wavelength demultiplexer connected to the first input / output waveguide, Multiple wavelength multiplexers, At least one second input / output waveguide connected to each of the plurality of wavelength multiplexers, A plurality of waveguides connecting the wavelength demultiplexer and the plurality of wavelength multiplexers. Equipped with, One end of the plurality of waveguides is connected to the wavelength demultiplexer, An optical signal processing device wherein the other ends of the plurality of waveguides are divided into k subsets (where k is an integer of 2 or more), and the other end of one or a plurality of adjacent waveguides in the i-th subset of the k subsets is connected to the i-th wavelength multiplexer (where i is an integer of 1 or more and k or less) among the k wavelength multiplexers.

2. The wavelength demultiplexer demultiplexes the wavelength multiplexed signal input via the first input / output waveguide to different wavelength multiplexers according to the wavelength, Each of the wavelength multiplexers combines light of the same wavelength that is input to it. The optical signal processing apparatus according to claim 1, configured as described above.

3. The optical signal processing apparatus according to claim 1, wherein the wavelength demultiplexer and the wavelength multiplexer are composed of a silicon oxide optical circuit.

4. The optical signal processing apparatus according to claim 1, wherein the wavelength demultiplexer and the wavelength multiplexer are composed of a silicon optical circuit.

5. The optical signal processing apparatus according to claim 1, wherein the wavelength demultiplexer and the wavelength multiplexer are composed of silicon nitride optical circuits.

6. The optical signal processing apparatus according to claim 1, wherein the wavelength demultiplexer and the wavelength multiplexer include an array waveguide diffraction grating.

7. The optical signal processing apparatus according to claim 1, wherein the wavelength demultiplexer and the wavelength multiplexer are formed in a planar optical circuit.

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