JP5750071B2 - Multi-wavelength light source device - Google Patents

Description

  The present invention relates to a multi-wavelength light source device, and more particularly to a multi-wavelength light source device capable of expanding a wavelength interval with a configuration that is reduced in size and reduced in power consumption.

  2. Description of the Related Art Conventionally, wavelength division multiplexing optical transmission systems have been used to increase transmission capacity in optical communication systems as communication traffic increases. In order to perform wavelength division multiplexing optical transmission, light sources corresponding to the number of wavelengths are required. For this reason, it is expensive as many as the number of light sources, and precise adjustment of the wavelengths of these light sources is required. Therefore, multi-wavelength light sources that collectively generate multi-wavelength light from a single light source have been studied.

  As a typical example of a multi-wavelength light source device, a device using supercontinuum (SC) light generation technology that generates multi-wavelength light at a constant wavelength interval is known. In wavelength multiplexing optical transmission, it is desirable that the frequency interval can be flexibly controlled in order to transmit various signals. In the SC light source, as a method of widening the wavelength interval, a method of connecting to a Fabry-Perot filter device in which two reflecting mirrors are opposed in parallel with high accuracy is known (for example, see Patent Document 1).

  FIG. 1 shows an example of a conventional multi-wavelength light source device. This is a multi-wavelength light source device described in Patent Document 1, and a Fabry-Perot filter device 102 is connected to the output of the supercontinuum light source 101. The supercontinuum light source 101 outputs multi-wavelength light having a wavelength interval Δλ1. The Fabry-Perot filter device 102 has a transmission wavelength band having a wavelength interval Δλ2 wider than the wavelength interval Δλ1, and can extract only the multiwavelength light having the wavelength interval Δλ2 from the multiwavelength light having the wavelength interval Δλ1.

  On the other hand, as a method of narrowing the wavelength interval, a method of connecting SC light sources in two stages (for example, see Patent Document 2) is known.

JP 2011-002623 A JP 2007-298765 A

  However, in the method described in Patent Document 1, it is necessary to strictly match the transmission wavelength of the Fabry-Perot filter device and the center wavelength of the SC light source, and the distance between the two reflecting mirrors constituting the Fabry-Perot filter device is precisely set. It is necessary to adjust to. In addition, it is necessary to adjust the temperature of the Fabry-Perot filter itself, which limits the miniaturization of the multi-wavelength light source. Moreover, in the system described in Patent Document 1, there is a wavelength that cannot pass through the Fabry-Perot filter in principle, and there is a limit to efficiency from the viewpoint of energy efficiency.

  On the other hand, in the method described in Patent Document 2, at least three SC light sources are required, and there is a limit to downsizing the multi-wavelength light source and reducing power consumption.

  An object of the present invention is to provide a multi-wavelength light source device capable of expanding the wavelength interval with a configuration that is reduced in size and reduced in power consumption.

In order to achieve the above object, the present invention provides a supercontinuum (SC) light source that outputs N wavelengths of continuous light having a wavelength interval Δλ1 simultaneously in the same phase. And a N × N-wavelength routing device having a wavelength interval Δλ1 having N optical input ports and N optical output ports, wherein the optical output port of the wavelength routing device Out of the first to Mth (M = 2 ⁿ <N: n is an integer equal to or greater than 2) optical output ports, L (L = N / M) continuous light with a wavelength interval Δλ2 is equally spaced. So that the optical output port of the SC light source and the first optical input port of the wavelength routing device are connected, and {L × (m−1) +1} of the wavelength routing device. Where m is an integer from 2 to L An M × 1-multiplexer having a wavelength interval Δλ1 is connected to the optical input port. Among the optical input ports of the wavelength routing device, the first optical input port and the {L × (m−1) +1 } An optical terminator is connected to the optical input ports other than the th optical input port, and {L × (m−1) +1} to {L × (m−1) + M} (wherein, m is an integer of 2 from L). The optical output port is connected to the M optical input ports of the multiplexer, and the wavelength interval Δλ2 = M × Δλ1.

  The wavelength routing device and the multiplexer can be an arrayed waveguide grating (AWG), and can be monolithically integrated with a planar optical circuit (PLC).

  As described above, according to the present invention, the SC light source and the N × N-wavelength routing device having the wavelength interval Δλ1 are provided, and the optical input / output port connection configuration of the wavelength routing device is changed to reduce the size and the size. It is possible to expand the wavelength interval with a configuration in which power consumption is reduced.

It is a figure which shows an example of the conventional multiwavelength light source device. It is a figure which shows the multiwavelength light source device concerning the 1st Example of this invention. It is a figure which shows the wavelength routing table of the wavelength routing apparatus concerning a 1st Example. It is a figure which shows the multiplexing characteristic of the multiplexer concerning a 1st Example. It is a figure which shows the mode of the wavelength routing in a 1st Example. It is a figure which shows the mode of the wavelength routing in a 1st Example. It is a figure which shows the multiwavelength light source device concerning the 2nd Example of this invention. It is a figure which shows the multiwavelength light source device concerning the 3rd Example of this invention. It is a figure for demonstrating the function of the collective wavelength converter concerning a 3rd Example. It is a figure which shows the wavelength conversion and multiplexing characteristic in a 3rd Example.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In all of the embodiments, the number of wavelengths N = 16, the number of external interfaces M = 4, and L = N / M = 4 are described and illustrated as an example, but the present invention is not limited to this. Needless to say.

(First embodiment)
FIG. 2 shows a multi-wavelength light source device according to the first embodiment of the present invention. In the multi-wavelength light source device 100, a 16 × 16-wavelength routing device 02 is connected to the output of the supercontinuum (SC) light source 01. Further, optical terminators 05, 4 × 1-multiplexers 06, 07, 08 are connected to the optical input port 02-1 of the wavelength routing device 02. The optical output port 01-01 of the SC light source 01 and the first optical input port 02-1-01) of the wavelength routing device 02 are connected to each other by an optical fiber 03-01. To the optical input port 02-1-01, continuous light (CW light) of N wavelengths aligned at the wavelength interval Δλ1 is simultaneously input from the SC light source 01 in the same phase.

  In the first embodiment, since the number of wavelengths N = 16, the wavelength routing device 02 has 16 optical input ports 02-1-01 to 02-1-16 and 16 optical output ports 02-. 2-01 to 02-2-16 are provided symmetrically.

  FIG. 3 shows a wavelength routing table of the wavelength routing apparatus according to the first embodiment. The wavelength routing table 10 indicates the optical input port number in the vertical direction and the optical output port number in the horizontal direction. When 16 CW lights of different wavelengths aligned at the wavelength interval Δλ1 are input to the first optical input port 02-1-01, the first optical output port 02-2-01 is input according to the cyclic wavelength routing table. To the 16th optical output port 02-2-16, continuous lights having wavelengths λ1 to λ16 are sequentially output.

Returning to FIG. 2, in the first embodiment, the four optical output ports 02-2-01 to 02-2-04 are connected to different optical fibers 04-01 to 04-04, respectively, and interface with the outside. Is configured. In the first embodiment, the number M of external interfaces is 4, but a number M satisfying M = 2 ⁿ <N (n is an integer of 2 or more) may be selected.

  On the other hand, among the optical input ports of the wavelength routing device 02, the fifth, ninth, and thirteenth optical input ports 03-05, 03-09, 03-13 in the optical input ports not connected to the SC light source 01. That is, {4 (= L) × (m−1) +1} (where m is an integer from 2 to L), the multiplexers 08, 07, and 06 are 03 for optical fibers, respectively. -05, 03-09, and 03-13. Other optical input ports 02-1-02 to 02-01-04, 02-1-06 to 02-1-08, 02-1-13-02-1-16 (first and {4 × (m -1) Optical terminators 05 other than the +1} th optical input port) are provided with optical fibers 03-02 to 03-04, 03-06 to 03-08, 03-10 to 03-12, 03-14. Are connected through ~ 03-16.

  Four optical output ports 02-2-05, 02-2-06, 02-2-07, 02-2-08 of the wavelength routing device 02, and optical input ports 06-1-01, 06 of the multiplexer 06 The optical fibers 04-05, 04-06, 04-07, and 04-08 are respectively connected to the -1-02, 06-1-03, and 06-1-04.

  FIG. 4 shows the multiplexing characteristics of the multiplexer according to the first embodiment. The multiplexing characteristic table 11 indicates the optical input port number in the vertical direction and the optical output port number in the horizontal direction. As shown in FIG. 3, CW lights of λ5 to λ8 are output to the four optical output ports 02-2-05 to 02-2-08 of the wavelength routing device 02 at the wavelength interval Δλ1. Accordingly, the CW lights of λ5 to λ8 are sequentially input to the four optical input ports 06-1-01 to 06-1-4- of the multiplexer 06. The multiplexer 06 multiplexes four CW lights of λ5 to λ8 and inputs them to the optical input port 02-1-13 of the wavelength routing device 02 via the optical fiber 03-13.

  Similarly, the optical output ports 02-2-09 to 02-2-12 of the wavelength routing device 02 are connected to the multiplexer 07, and the CW lights of λ9 to λ12 are connected to the optical input ports 02-1-09. 4 waves are multiplexed and input. The optical output ports 02-2-13 to 02-2-16 of the wavelength routing device 02 are connected to the multiplexer 08, and four CW lights of λ13 to λ16 are multiplexed into the optical input ports 02-1-05. Enter. That is, {4 (= L) × (m−1) +1} to {4 (= L) × (m−1) + M} (where m is an integer from L to 2) -th optical output of the wavelength routing device A port is connected to the M optical input ports of the multiplexer.

  5 and 6 show the state of wavelength routing in the first embodiment. The wavelength routing table 10-1 represents the first wavelength routing, and 16 CW lights having wavelengths λ1 to λ16 at a wavelength interval Δλ1 are connected to the first optical input port 02-1-01 of the wavelength routing device 02. Is output to the optical output ports 02-2-01 to 02-2-16, respectively. Among these, 12 CW lights having wavelengths λ5 to λ16 are input to the multiplexers 06, 07, and 08, respectively, and four waves are multiplexed, respectively, so that the three optical input ports 03-05 and 03 of the wavelength routing device 02 are multiplexed. -09 and 03-13.

  The wavelength routing table 10-2 represents the second wavelength routing, and the four-wave multiplexed CW light is transmitted to the four optical output ports 02-2-01 to 02-2-04 of the wavelength routing device 02. Each wavelength is routed and output.

  As described above, (λ1, λ5, λ9, λ13), (λ2, λ6, λ10, λ14), (λ3, λ7) are respectively output from the four optical output ports 02-2-01 to 02-2-04 of the wavelength routing device. , Λ11, λ15) and (λ4, λ8, λ12, λ16) are output. At this time, the wavelength interval of the CW light output from each optical output port is not Δλ1. That is, Δλ2 = 4 (= M) × Δλ1, and a multi-wavelength light source device in which the wavelength interval is expanded four times can be provided.

(Second embodiment)
In the first embodiment, it is assumed that the multi-wavelength light source device is used as a CW light source. When used as a light source for optical communication, connection with an external optical modulator that can superimpose a data signal on CW light is required. In the second embodiment, a connection configuration with the external optical modulators 12, 13, 14, 15 is shown.

  FIG. 7 shows a multi-wavelength light source apparatus according to the second embodiment of the present invention. The multi-wavelength light source device 200 has a configuration in which a duplexer, an external modulator, and a multiplexer are connected to the output of the multi-wavelength light source device 100 of the first embodiment. The four external interface ports 09-01 to 09-04 (corresponding to the optical output ports 02-2-01 to 02-2-04) of the multi-wavelength light source device 100 are 1 × 4-demultiplexers having a wavelength interval Δλ2. 12-1, 13-1, 14-1, and 15-1 are connected via four optical fibers 04-01, 04-02, 04-03, and 04-04.

  For example, in the demultiplexer 12-1, CW light is demultiplexed from the four output ports 12-1-1-1 to 12-1-4, respectively, and four external modulators 12-2-1 via optical fibers. To 12-2-4. In the external modulator, data is superimposed on the CW light to generate an optical signal. The outputs of the external modulators 12-2-1 to 12-2-4 are sent to the four input ports 12-3-1 to 12-3-4 of the 4 × 1-multiplexer 12-3 whose wavelength interval is Δλ2. Entered. The four-wave multiplexed optical signal is output from the external interface port 12-4.

  Similarly, the other three demultiplexers 13-1, 14-1, and 15-1 are connected to the external modulators, respectively, and three optical signals that are four-wave multiplexed are three external interface ports. 12-5, 12-6, 12-7). As described above, it is possible to provide a multi-wavelength light source device in which Δλ2 = 4 × Δλ1 and the wavelength interval is expanded four times.

  In FIG. 7, four demultiplexers and four multiplexers are illustrated as separate components, but are configured as one component by an AWG that is a flat optical circuit integrated on a single substrate. can do. Needless to say, 16 optical modulators can be integrated on one substrate.

(Third embodiment)
In the second embodiment, there are M = 4 external interfaces as the multi-wavelength light source device 200. When one optical fiber can be connected to the external interface, further wavelength multiplexing is required. In the third embodiment, a configuration in the case where the number of external interfaces is one will be described.

  FIG. 8 shows a multi-wavelength light source apparatus according to the third embodiment of the present invention. The multi-wavelength light source device 300 includes the multi-wavelength light source device 100 of the first embodiment. And.

  Collective wavelength converters 18, 19, and 20 are inserted between the multi-wavelength light source device 100 and the three duplexers 13-1, 14-1, and 15-1, respectively. The batch wavelength converters 18 to 20 collectively convert a plurality of input wavelengths by a nonlinear effect caused by a lithium niobate material and a nonlinear fiber. In the third embodiment, wavelength conversion is performed with an integral multiple of Δλ3 (= 4 × Δλ2).

The function of the collective wavelength converter according to the third embodiment will be described with reference to FIG. FIG. 9A shows four CWs in which four-wave multiplexed CW light (λ _{n to} λ _{n + 3} ) is collectively separated by a wavelength interval Δλ 3 (= 4 × Δλ 2) in the collective wavelength converter 18. This shows that the light has been converted into light (λ ′ _{n to} λ ′ _{n + 3} ). 9B shows a case where wavelength conversion of the wavelength interval 2 × Δλ3 is performed in the collective wavelength converter 19, and FIG. 9C shows that wavelength conversion of the wavelength interval of 3 × Δλ3 is performed in the collective wavelength converter 20. The case where it went is shown. In either case, the wavelength interval of each CW light maintains Δλ2.

  Similar to the second embodiment, the external modulators 12 to 15 superimpose data on the CW light to generate an optical signal. The superimposed optical signal has 16 optical input ports and is input to the 16 × 1-multiplexer 16 having a wavelength interval Δ2.

  FIG. 10 shows wavelength conversion and multiplexing characteristics in the third embodiment. At the output of the multiplexer 16, 16 optical signals that have been wavelength-routed and have data superimposed on the CW light are output from one external interface 17 through an optical fiber. As described above, it is possible to provide a multi-wavelength light source device in which Δλ2 = 4 × Δλ1 and the wavelength interval is expanded four times.

01: Supercontinuum (SC) light source 02: Wavelength routing device 06, 07, 08: Multiplexer 10: Wavelength routing table 11: Multiplexing characteristic table 12-1, 13-1, 14-1, 15- 1: demultiplexer 12-2, 13-2, 14-2, 15-2: external optical modulator 12-3, 13-3, 14-3, 15-3: multiplexer 16: multiplexer 100 , 200, 300: Multi-wavelength light source device

Claims (8)

A supercontinuum (SC) light source that simultaneously outputs N wavelengths of continuous light having a wavelength interval Δλ1 in the same phase;
A multi-wavelength light source device including an N × N-wavelength routing device having a wavelength interval Δλ1 having N optical input ports and N optical output ports,
Among the optical output ports of the wavelength routing device, L (L = N / M) wavelength intervals Δλ2 from the first to Mth optical output ports (M = 2 ⁿ <N: n is an integer of 2 or more). ) So that continuous light with a wavelength of
The optical output port of the SC light source and the first optical input port of the wavelength routing device are connected, and {L × (m−1) +1} (where m is an integer from 2 to L) of the wavelength routing device. An M × 1-multiplexer having a wavelength interval Δλ1 is connected to the first optical input port, and among the optical input ports of the wavelength routing device, the first optical input port and the {L × (m−1) ) Optical terminators are connected to optical input ports other than the +1} th optical input port,
{L × (m−1) +1} to {L × (m−1) + M} (where m is an integer from L to M) th optical output port of the wavelength routing device is M in the multiplexer. Connected to the optical input port of
A multi-wavelength light source device characterized in that the wavelength interval Δλ2 = M × Δλ1. M 1 × L-demultiplexers with a wavelength interval Δλ2 connected to each of the first to Mth optical output ports of the wavelength routing device;
M × L optical modulators connected to each of the L optical output ports of the 1 × L-demultiplexer;
2. The multi-wavelength light source device according to claim 1, further comprising: M L × 1-multiplexers with a wavelength interval Δλ <b> 2 connected to each of the optical output ports of the optical modulator. A 1 × L-demultiplexer having a wavelength interval Δλ2 connected to the first optical output port of the wavelength routing device;
A collective wavelength converter connected to each of the second to Mth optical output ports of the wavelength routing device;
M-1 1 × L-demultiplexers with a wavelength interval Δλ2 connected to outputs of the batch wavelength converters;
M × L optical modulators connected to each of the L optical output ports of the 1 × L-demultiplexer;
The multi-wavelength light source device according to claim 1, further comprising: an N × 1-multiplexer having a wavelength interval Δλ 2 to which all of the optical output ports of the optical modulator are connected.   The multi-wavelength light source device according to claim 1, wherein the wavelength routing device and the multiplexer are arrayed waveguide diffraction gratings.   The multi-wavelength light source device according to claim 1, wherein the wavelength routing device and the multiplexer are monolithically integrated by a planar optical circuit (PLC).   The multi-wavelength light source device according to claim 2, wherein the wavelength routing device, the multiplexer, and the duplexer are arrayed waveguide diffraction gratings.   4. The multi-wavelength light source device according to claim 2, wherein the wavelength routing device, the multiplexer, and the duplexer are monolithically integrated by a planar optical circuit (PLC). 5.   The multi-wavelength light source device according to claim 7, wherein the optical modulator is further monolithically integrated by a planar optical circuit (PLC).

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