JP2000324052A - Wavelength multiplex type add/drop device and wavelength multiplex type add/drop method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To flexibly cope with variation in the used wavelength of an optical network by connecting output ports of respective paths of an optical path changeover switches to input pots of next-stage paths in order, inserting multiple reflection type wavelength selecting elements into multiple optical waveguides, reflecting a signal light of a given wavelength and transmitting light signals of other wavelength, and separating a main transmitted signal light and an add signal light. SOLUTION: The main signal light inputted from a main input port 56 to a port 1 of an optical circulator 11 is outputted from a port 2 and inputted to a path A1 of an optical path changeover switch 13a. This signal light passes through the path A1 and a 2×2 switch #1 and is inputted to a reflection type wavelength selecting element 14-1. Signal lights except wavelength λ1 are transmitted through a reflection type wavelength selecting element 14-1 and inputted to a path A2 of the optical path changeover switch 13a through a optical waveguide 15a. Signal of wavelength pk1 is reflected by the reflection type wavelength selecting element 14-1 to travel backward through the path A1 and is outputted to a drop port 58.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wavelength multiplexing type add / drop device and a wavelength multiplexing type add / drop method for dropping / adding a predetermined wavelength in an optical node of an optical network using a wavelength multiplexing / demultiplexing technique.

[0002]

2. Description of the Related Art In an optical network using the wavelength division multiplexing / demultiplexing technology, a wavelength division multiplexing type add / drop device (hereinafter referred to as "optical ADM") which freely exchanges each wavelength signal in an optical node.
Drop Multiplexer) ") is an important component. As a configuration of the optical ADM, for example, two sets of arrayed waveguide gratings (hereinafter referred to as “AWG (Arrayed Waveguide Gr
ating)), and a 2 × 2 Mach-Zehnder thermo-optical switch (hereinafter referred to as a “TO switch”) arranged for each channel is integrated on one circuit by a quartz PLC manufacturing technique. .

FIG. 12 shows a configuration example of a conventional optical ADM using an AWG and a TO switch. In the figure, AWG5
A TO switch 55 is provided between an optical waveguide connecting between the AWG 54 and the AWG 54 and an optical waveguide connecting between the AWG 52 and the AWG 53. A predetermined wavelength signal is added and dropped by switching the TO switch 55. .

Here, when all the TO switches 55 are off, the wavelength-multiplexed main signal light input from the main input port 56 is first split by the AWG 51,
The signal is multiplexed again by the AWG 53 through the cross port of the TO switch 55, and is output to the main output port 57 as main transmitted signal light. Next, a predetermined TO switch 55
Is turned on, of the wavelength signals demultiplexed by the AWG 51, the wavelength signal input to the turned-on TO switch 55 is multiplexed by the AWG 54 through its through port,
The light is output from the drop port 58 as a drop signal light.

The add signal light input from the add port 59 is split by the AWG 52 and multiplexed by the AWG 53 through the through port of the TO switch 55 which is turned on.
The signal is output to the main output port 57 in place of the drop signal light output to the drop port 58.

In the optical ADM, data processing is performed on the drop signal light and output as an add signal light on the same channel (wavelength) to perform data transmission to an adjacent terminal station. There is a configuration in which cross-connection is performed by exchanging signals and outputting as add signal light of another channel (wavelength).

[0007]

SUMMARY OF THE INVENTION Optical AD using AWG
For M, the wavelength to be input and output is determined in advance according to the characteristics of the AWG. That is, the capacity is fixed, and it is difficult to add a channel or change a used wavelength according to demand, which hinders the configuration of a flexible optical network.

[0008] In addition, although AWGs capable of multiplexing / demultiplexing wavelengths of 16 channels or 64 channels have been realized, no further increase in capacity has been realized so far. Therefore, for example, it could not be used as an optical ADM in an optical network that handles 254 wavelength-multiplexed optical signals.

The conventional optical ADM has a configuration in which a wavelength-division multiplexed optical signal is once demultiplexed into respective wavelengths by an AWG, a wavelength to be added / dropped is selected from the wavelengths by a TO switch, and further multiplexed by an AWG. ing. Therefore, when such optical ADMs are connected in multiple stages via an optical transmission line having chromatic dispersion, the wavelength band is limited.

An optical ADM using a TO switch is
It is difficult to save energy during operation because power is always required for a channel that has no self-holding property and is added and dropped. Also, if the power supply is interrupted in an emergency, it is no longer possible to add / drop using the optical ADM, and it is necessary to reset it when restoring. For this reason, there has been a problem that the maintenance cost becomes enormous in order to increase the reliability as a lifeline.

According to the present invention, there is provided a wavelength multiplexing type add / drop apparatus which can add / drop a predetermined wavelength by using a switch element having a self-holding function, and can flexibly cope with a change in a wavelength used in an optical network. An object of the present invention is to provide a wavelength multiplexing type add / drop method.

[0012]

The optical ADM according to claim 1 is:
It is composed of an optical path switch, two optical circulators, a plurality of optical waveguides, and a plurality of reflection type wavelength selection elements, and passes through the reflection type wavelength selection element according to the state of each 2 × 2 switch of the optical path selection switch. In this configuration, a route or a bypass route is selected, and an add / drop wavelength is selected.

The optical path switch includes a plurality of paths A arranged in parallel, a path B intersecting the plurality of paths A, and a plurality of non-power self-holding type switches for switching an optical path at each intersection of the paths A and B. One end of each path A is used as an input port, the other end is used as an output port, and the input port of the first-stage path A or one end of the path B inputs and outputs a main signal light and a drop signal light. The output port of the final path A or the other end of the path B is a second input / output port for inputting / outputting the main transmitted signal light and the add signal light.

The first optical circulator includes a main signal light input to a first input / output port of the optical path changeover switch,
The drop signal light output from the same port is separated. The plurality of optical waveguides sequentially connect the output port of each path A of the optical path changeover switch and the input port of the path A of the next stage. The plurality of reflective wavelength selection elements are inserted into the plurality of optical waveguides,
Each reflects signal light of a predetermined wavelength and transmits signal light of another wavelength. The second optical circulator separates the main transmitted signal light output from the second input / output port of the optical path switch and the add signal light input to the same port.

According to a second aspect of the present invention, there is provided an optical ADM comprising an optical path switch, two optical circulators, a plurality of optical waveguides, and a plurality of reflection-type wavelength selection elements. In this configuration, a path that passes through the reflection-type wavelength selection element or a path that bypasses the reflection-type wavelength selection element is selected, and an add / drop wavelength is selected.

The optical path switch includes a plurality of paths A arranged in parallel, a path B intersecting the plurality of paths A, and a plurality of powerless self-holding type switches for switching an optical path at each intersection of the paths A and B. 2 × 2 switch, one end of each path A as an input port, the other end as an output port, and one end of a path B for inputting / outputting a main signal light and a drop signal light.
The input / output port and the other end are second input / output ports for inputting / outputting the main transmitted signal light and the add signal light.

The first optical circulator comprises: a main signal light input to a first input / output port of the optical path changeover switch;
The drop signal light output from the same port is separated. The plurality of optical waveguides respectively connect the input port and the output port of each path A of the optical path switch. The plurality of reflection-type wavelength selection elements are inserted into the plurality of optical waveguides, each of which reflects signal light of a predetermined wavelength and transmits signal light of another wavelength. The second optical circulator separates the main transmitted signal light output from the second input / output port of the optical path changeover switch from the add signal light input to the same port.

An optical ADM according to a fourth aspect of the present invention comprises an optical path switch using a 2 × 2 switch unit, two optical circulators, a plurality of optical waveguides, and a plurality of reflection type wavelength selection elements. In this configuration, a path passing through or bypassing the reflection type wavelength selection element is selected according to the state of each 2 × 2 switch unit, and an add / drop wavelength is selected.

The optical path changeover switch has two 1 × 2 switches of a powerless self-holding type. One terminal port of the first 1 × 2 switch is a first input port, and two terminals of the second 1 × 2 switch are two. One of the terminal ports is a second input port, the first 1 × 2
One of the two terminal ports of the switch is a first output port,
Of the 1 × 2 switch of the first 1 × 2 switch as the second output port, and the other of the two terminal ports of the first 1 × 2 switch and the second output port.
2 connected to the other of the two terminal ports of the 1 × 2 switch
In this configuration, a plurality of × 2 switch units are arranged in parallel.

The first optical circulator separates the main signal light input to the first input port of the first 2 × 2 switch unit of the optical path changeover switch from the drop signal light output from the same port. The plurality of optical waveguides connect the first output port and the second input port of each 2 × 2 switch unit of the optical path changeover switch, and respectively connect the second output port and the first input port of the next stage 2 × 2 switch unit. Connecting. The plurality of reflection-type wavelength selection elements are inserted into an optical waveguide connecting the first output port and the second input port of the 2 × 2 switch unit, and each reflect signal light of a predetermined wavelength and signal light of another wavelength. Through. The second optical circulator is a 2 × 2 at the last stage of the optical path switch.
The main transmission signal light output from the second output port of the switch unit is separated from the add signal light input to the same port.

[0021]

(First Embodiment) FIG. 1 shows a first embodiment of the present invention. Here, a configuration example in the case where the wavelength to be added / dropped is λ1 to λ4 is shown. In the figure, 11 and 12 are optical circulators, 13a is an optical path changeover switch, 14-1 to 14-4 are reflection type wavelength selection elements,
15a is an optical waveguide.

The optical path changeover switch 13a includes five paths A1 to A5 arranged in parallel and a path B intersecting therewith.
And 2 × 2 switch # 1 that switches the optical path at the intersection
To $ 5. In the 2 × 2 switch, as shown in FIG. 2, in state 0, path A and path B are in an orthogonal state, and both signal lights are transmitted without interference, and in state 1, path A
Is converted to the path B, and the path B is converted to the path A.

The main input port 56 and the port 1 of the optical circulator 11 are connected. The reflection type wavelength selecting element 14-1 is connected to the port 2 of the optical circulator 11 via the input port of the path A1 of the optical path switch 13a, the 2 × 2 switch # 1, and the output port of the path A1. Optical path changeover switch 13 via optical waveguide 15a
The input port of the path A2 of a is connected. Similarly,
The input ports of the following paths A3 to A5 are connected to the passing ends of the reflection type wavelength selection elements 14-2 to 14-4, respectively, and the optical circulator 12 is further connected via the 2 × 2 switch # 5 and the output port of the path A5. Port 2 is connected. Port 3 of the optical circulator 12 has a main output port 57
Is connected. Port 3 of the optical circulator 11
Port 58 is connected to the optical circulator 1
The add port 59 is connected to the port 1 of the second.

FIG. 3 shows the state of the optical path switch 13a when the signal light of the wavelength λ1 is added and dropped. 2
× 2 switches # 1 to # 5 are in the states 0, 1, 0,
It is set to 0,1.

The main signal light input from the main input port 56 to the port 1 of the optical circulator 11 is output from the port 2 and is output to the path A1 of the optical path switch 13a.
Is input to This signal light passes through the path A1 and the 2 × 2 switch # 1, and is input to the reflection-type wavelength selection element 14-1. The signal light other than the wavelength λ1 is transmitted through the reflection-type wavelength selection element 14-1, and is input to the path A2 of the optical path switch 13a via the optical waveguide 15a. The signal light having the wavelength λ1 is reflected by the reflection-type wavelength selection element 14-1 and is reflected on the path A.
1, and is output from the port 3 of the optical circulator 11 to the drop port 58 as a drop signal light.

The signal light excluding the wavelength λ1 input to the path A2 of the optical path changeover switch 13a moves to the path B by the 2 × 2 switch # 2, and passes through the 2 × 2 switches # 3 and # 4 to the 2 ×.
The signal is input to the second switch # 5, is transferred to the path A5, is input to the port 2 of the optical circulator 12, and is output from the port 3 to the main output port 57 as transmitted signal light.

When the add signal light having the wavelength λ1 is input from the port 1 of the optical circulator 12, the input signal light is input from the port 2 to the optical path switch 13a, and the 2 × 2 switch ♯
5, ♯4, ♯3, ♯2, input to the reflection-type wavelength selection element 14-1 via the optical waveguide 15a, reflected, reflected, returned to the port 2 of the optical circulator 12, and transmitted from the port 3 to the main transmission. The signal is superimposed on the signal light and output to the main output port 57.

Table 1 shows 2 × 2 of the optical path changeover switch 13a.
The relationship between the switch state and the add / drop wavelength and transmission wavelength is shown.

[0029]

[Table 1] When the main signal light input from the main input port 56 includes a wavelength that does not correspond to the wavelength selected by the reflection-type wavelength selection elements 14-1 to 14-4, all of the signal lights are transmitted signals. Output from the main output port 57. That is, unlike the optical ADM using the AWG, the optical ADM of the present invention can add a channel of a new wavelength.

Further, in the configuration of the first embodiment, the main signal light may be inputted from the path B of the optical path switch 13a. In this case, the state 0 and the state 1 of the 2 × 2 switch # 1 in Table 1 may be reversed. Also,
Route the main transmitted signal light to the path B of the optical path switch 13a.
May be output. In that case, 2 × in Table 1
The state 0 and the state 1 of the switch # 5 may be reversed.

(Second Embodiment) FIG. 4 shows a second embodiment of the present invention.
An embodiment will be described. Here, a configuration example in the case where the wavelength to be added / dropped is λ1 to λ4 is shown. In the figure, 1
Reference numerals 1 and 12 denote optical circulators, 13b denotes an optical path changeover switch, 14-1 to 14-4 denote reflection wavelength selection elements, and 15b
Is an optical waveguide. The difference from the first embodiment is that the configuration of the optical path switch 13b and the optical path switch 13b
This is a connection form between the optical waveguide 15b and the optical waveguide 15b.

The optical path changeover switch 13b includes four paths A1 to A4 arranged in parallel and a path B intersecting therewith.
And 2 × 2 switch # 1 that switches the optical path at the intersection
~ $ 4. In the 2 × 2 switch, as shown in FIG. 2, in state 0, path A and path B are in an orthogonal state, and both signal lights are transmitted without interference, and in state 1, path A
Is converted to the path B, and the path B is converted to the path A.

The main input port 56 and the port 1 of the optical circulator 11 are connected. The port 2 of the optical circulator 11 has a path B of the optical path changeover switch 13b, 2 ×
The reflection type wavelength selection element 14-1 is connected to the 2 switch # 1 via the output port of the path A1, and the input port of the path A1 of the optical path changeover switch 13b is connected to the passing end thereof via the optical waveguide 15b. Similarly, the paths A2 to A4 of the optical path changeover switch 13b are connected in a loop via the reflection-type wavelength selection elements 14-2 to 14-4 and the optical waveguide 15b, respectively. Port 2 of circulator 12 is connected. The main output port 57 is connected to the port 3 of the optical circulator 12. The drop port 58 is connected to the port 3 of the optical circulator 11, and the add port 59 is connected to the port 1 of the optical circulator 12.

FIG. 5 shows the state of the optical path switch 13b when the signal light having the wavelength λ1 is added or dropped. 2
The × 2 switches # 1 to # 4 have states 1, 0, 0,
Set to 0.

The main signal light input from the main input port 56 to the port 1 of the optical circulator 11 is output from the port 2 and input to the path B of the optical path switch 13b. This signal light is transferred from the path B to the path A1 by the 2 × 2 switch # 1, and is input to the reflection-type wavelength selection element 14-1.
5b is input to the path A1 of the optical path switch 13b. The signal light having the wavelength λ1 is transmitted to the reflection type wavelength selection element 14.
The light is reflected at −1, and travels back through the paths A1 and B, and is output from the port 3 of the optical circulator 11 to the drop port 58 as a drop signal.

The signal light excluding the wavelength λ1 input to the path A1 of the optical path changeover switch 13b is transferred to the path B by the 2 × 2 switch # 1, passes through the 2 × 2 switches # 2 to # 5 in order, and becomes an optical circulator. The signal is input to port 2 of port 12, and is output from port 3 to main output port 57 as transmitted signal light.

When the add signal light having the wavelength λ1 is input from the port 1 of the optical circulator 12, the input signal light is input from the port 2 to the optical path switch 13b, and the 2 × 2 switch ♯
4, .SIGMA.3, .SIGMA.2, .SIGMA.1 and are input to the reflection-type wavelength selection element 14-1 via the optical waveguide 15b, reflected, reflected, returned to the port 2 of the optical circulator 12, and transmitted from the port 3 to the main transmission. The signal is superimposed on the signal light and output to the main output port 57.

Table 2 shows 2 × 2 of the optical path changeover switch 13b.
The relationship between the switch state and the add / drop wavelength and transmission wavelength is shown.

[0039]

[Table 2] When the main signal light input from the main input port 56 includes a wavelength that does not correspond to the wavelength selected by the reflection-type wavelength selection elements 14-1 to 14-4, all of the signal lights are transmitted signals. Output from the main output port 57. That is, unlike the optical ADM using the AWG, the optical ADM of the present invention can add a channel of a new wavelength.

(Third Embodiment) 2 × 2 switches of the optical path switch 13a of the first embodiment shown in FIG. 1, FIG.
2 × of the optical path changeover switch 13b of the second embodiment shown in FIG.
The two switches can be configured using two 1 × 2 switches. FIG. 6 shows two 1 × 2 switches {ia,}
reflection type wavelength selection element (selection wavelength λi) 14 using ib
-Indicates a 2x2 switch unit that switches whether to pass i. Assuming that the state 0 of the 1 × 2 switches ♯ia and ♯ib is transmitted and the state 1 is reflected, as shown in FIG. 7, in the state (0, 0), the path passes through the reflective wavelength selection element 14-i, In the state (1, 1), the reflection type wavelength selection element 1
The route bypasses 4-i.

FIG. 8 shows a third embodiment of the present invention using the 2 × 2 switch unit of FIG. 6 instead of the 2 × 2 switches # 1 to # 4 of the optical path changeover switch 13b of FIG. For example, the 2 × 2 switch # 1 in FIG. 4 corresponds to the 1 × 2 switches # 1a and # 1b in FIG. The add / drop operation and the transmission operation of the signal light having the wavelengths λ1 to λ4 are the same as in the second embodiment. That is, the state 0 of the switch #i in Table 2 is associated with the state (1, 1) of the 1 × 2 switches #ia and #ib in FIG.
By associating the states (0, 0) of the switches #ia and #ib, the operation of the optical ADM shown in FIG.

FIG. 9 shows a configuration equivalent to the third embodiment of the present invention. The difference from the third embodiment shown in FIG. 8 is that the 1 × 2 switches # 1a, # 1b of the optical path switch 13d
This is where the connection directions of # 4a and # 4b are changed. However, the state 0 of the switch #i in Table 2 and the 1 × in FIG.
The state (0, 0) of the two switches ♯ia and ♯ib is associated with the state 1 of the switch ♯i and the 1 × 2 switch ♯ia, ♯
The state (1, 1) of ib is associated. The present configuration has a feature that the optical waveguide connecting the passing end of the reflection-type wavelength selection element and the next 1 × 2 switch does not need to be largely routed, and can be made compact as a whole.

(Embodiment) FIG. 10 shows an embodiment of the optical path changeover switches 13a and 13b used in the optical ADM of the present invention.

The optical path changeover switches 13a, 13 of this embodiment
The 2 × 2 switch of b is called a “thermocapillary light switch”,
An extremely thin groove is cut in the intersecting waveguides at an angle of 45 degrees to the optical axis of each waveguide, and the index matching oil is slid in the groove by thermal capillary action to switch between total reflection and transmission. is there. That is, when the oil is located at the intersection of the waveguides, the light is transmitted as it is, and when the oil is not located at the intersection of the waveguides, the light path is switched by totally reflecting the light to another intersecting waveguide. It has become. The thermocapillary optical switch has a self-holding property that consumes electric power only at the time of state switching, and has a characteristic that there is no wavelength dependence and polarization dependence in principle (references:
JP-A-8-62645 (Japanese Patent Application No. 6-19525)
9. Surface hearing thermal control type waveguide optical switch and matrix type optical switch)).

Such optical path changeover switches 13a, 13
In the state b, the 2 × 2 switches are simultaneously switched according to the patterns shown in Table 1 or Table 2 according to the add / drop wavelength to be set. As a configuration for performing the switching, the memory 2 storing the pattern of Table 1 or Table 2 is used.
1 and a control unit 2 for driving and controlling a corresponding 2 × 2 switch by referring to a memory according to an add / drop wavelength to be set
2 and a bus control interface 23 for remote control by commands from the center.

The reflection-type wavelength selection element 14 may be one in which fiber gratings having predetermined transmission wavelengths are connected in a loop. Also,
The optical path switch 13, the reflection type wavelength selection element 14, and the optical waveguide 15 may all be integrated on the same substrate. Such an element can be usually manufactured using a quartz-based planar waveguide optical circuit (PLC), but can also be manufactured using an InP-based semiconductor substrate.

A 2 × 2 switch called a “thermocapillary light switch” used for the light path changeover switches 13a and 13b can simultaneously transmit or totally reflect input from two directions as shown in FIG. Although possible, it can also be used as a 1 × 2 switch used for the optical path changeover switches 13c and 13d.

As the 1 × 2 switch used for the optical path changeover switches 13c and 13d, for example, a latch type switch using fiber micromachine technology can be used (reference: S. Nagaoka, "Compact Latching-Type").
Single-Mode-Fiber Switches Fabricated by a Fiber-
Micromachining Technique and Their Practical Appli
cations ", IEEE JOURNAL OF SELECTED TOPICS IN QUANTU
M ELECTRONICS, VOL.5, NO.1, JAN./FEB., 1999).

This is, as shown in FIG. 11, one movable optical fiber 31 and two fixed optical fibers 32-1 and 32.
The movable optical fiber 31 is coated with a magnetic material 33 on the movable optical fiber 31 and magnetically driven using a solenoid coil 34 and a magnet 35 to move the movable optical fiber 31 to the two fixed optical fibers 32-1 and 32-2. In this configuration, one of them is directly opposed.

[0050]

As described above, according to the present invention, a resettable wavelength multiplexing type add / drop device (optical ADM) can be provided with a simple configuration and at low cost, and a switch element having a self-holding property is used. As a result, operation cost and power saving can be achieved.

Further, since signal light other than the wavelength reflected by the built-in reflection type wavelength selection element is transmitted, it is possible to add a new wavelength channel without renewing the installed equipment. is there. As a result, an extremely scalable optical network can be constructed.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment of the present invention.

FIG. 2 is a diagram showing a state of a 2 × 2 switch.

FIG. 3 is a diagram illustrating a state of an optical path changeover switch 13a when a signal light having a wavelength λ1 is added and dropped.

FIG. 4 is a diagram showing a second embodiment of the present invention.

FIG. 5 is a diagram showing a state of an optical path changeover switch 13b when a signal light having a wavelength λ1 is added / dropped.

FIG. 6 shows a 2 × configuration using two 1 × 2 switches.
The figure which shows the structure of a two switch unit.

FIG. 7 is a diagram showing a state of a 2 × 2 switch unit.

FIG. 8 is a diagram showing a third embodiment of the present invention.

FIG. 9 is a diagram showing a configuration equivalent to the third embodiment of the present invention.

FIG. 10 is a diagram showing a configuration of an embodiment of optical path changeover switches 13a and 13b.

FIG. 11 is a diagram showing an embodiment configuration of a 1 × 2 switch.

FIG. 12 shows a conventional optical AD using an AWG and a TO switch.
The figure which shows the structural example of M.

[Explanation of symbols]

11, 12 Optical circulator 13a, 13b, 13c, 13d Optical path changeover switch 14-1 to 14-4 Reflection type wavelength selection element 15a, 15b, 15c Optical waveguide 21 Memory 22 Control unit 23 Bus control interface 31 Movable optical fiber 32-1 , 32-2 Fixed optical fiber 33 Magnetic material 34 Solenoid coil 35 Magnet 51-54 Array waveguide diffraction grating (AWG) 55 Mach-Zehnder thermo-optic switch (TO switch) 56 Main input port 57 Main output port 58 Drop port 59 Add port

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G02B 6/28 B (72) Inventor Fumiwa Ohira 3-19-2 Nishishinjuku, Shinjuku-ku, Tokyo Nippon Telegraph and Telephone Inside Telephone Co., Ltd. (72) Inventor Tomomi Sakata 3-192-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Japan Telegraph and Telephone Corporation (72) Inventor Hitoshi Ohara 3-2-1, Nishi-Shinjuku, Shinjuku-ku, Tokyo Nippon Telegraph and Telephone Telephone Co., Ltd. F-term (reference) 2H041 AA06 AA14 AC04 2H047 KB01 LA01 LA19 LA26 TA00 5K002 BA02 BA04 BA05 BA06 BA21 CA05 DA02 FA01 5K069 AA13 BA09 DA05 DB33 DB35 DB36 EA24 EA25

Claims (12)

[Claims] 1. A plurality of paths A arranged in parallel, a path B intersecting the paths A, and a plurality of powerless self-holding 2 × switching optical paths at each intersection of the paths A and B. 2
One end of each path A is an input port, the other end is an output port, and the input port of the first stage path A or one end of the path B is a first input / output terminal for inputting / outputting main signal light and drop signal light. An optical path changeover switch serving as an output port, and having the other end of the output port of the path A or the other end of the path B as a second input / output port for inputting / outputting a main transmitted signal light and an add signal light; A first optical circulator for separating a main signal light input to one input / output port, a drop signal light output from the same port, an output port of each path A of the optical path changeover switch and a path A of a next stage. A plurality of optical waveguides for sequentially connecting input ports, and a plurality of reflection types inserted into the plurality of optical waveguides, each of which reflects signal light of a predetermined wavelength and transmits signal light of another wavelength. A length selection element; and a second optical circulator for separating a main transmitted signal light output from a second input / output port of the optical path switch and an add signal light input to the port. A wavelength multiplexing type add / drop apparatus, wherein a path passing through the reflective wavelength selecting element or a bypassing path is selected in accordance with the state of each 2 × 2 switch, and an add / drop wavelength is selected. . 2. A plurality of paths A arranged in parallel, a path B intersecting the paths A, and a plurality of 2 × power-free self-holding type switching optical paths at each intersection of the paths A and B. 2
One end of each path A as an input port, the other end as an output port, one end of the path B as a first input / output port for inputting / outputting main signal light and drop signal light, and the other end as a main input / output port. An optical path switch serving as a second input / output port for inputting / outputting the transmitted signal light and the add signal light, a main signal light input to a first input / output port of the optical path switch, and a drop signal output from the port A first optical circulator for separating light, a plurality of optical waveguides respectively connecting an input port and an output port of each path A of the optical path changeover switch, and a signal having a predetermined wavelength inserted into each of the plurality of optical waveguides A plurality of reflective wavelength selection elements that reflect light and transmit signal light of another wavelength; and a main transmission signal output from a second input / output port of the optical path switch. A light and a second optical circulator for separating an add signal light input to the same port; and a path passing through the reflective wavelength selection element according to the state of each 2 × 2 switch of the optical path changeover switch or A wavelength division multiplexing type add / drop apparatus, wherein a bypass route is selected and an add / drop wavelength is selected. 3. The wavelength-division multiplexing add / drop device according to claim 1, wherein the 2 × 2 switch constituting the optical path changeover switch includes two orthogonal waveguides and an intersection between the two waveguides. A thermo-capillary optical switch including a groove formed at an angle of 45 degrees with respect to the optical axis of the waveguide, and a refractive index matching oil that switches between total reflection and transmission by sliding in the groove by a thermo-capillary phenomenon. A wavelength multiplexing type add / drop device characterized by the above-mentioned. 4. A switch having two 1 × 2 switches of a powerless self-holding type, wherein one terminal port of a first 1 × 2 switch is connected to a first terminal.
An input port, one of the two terminal ports of the second 1 × 2 switch is a second input port, one of the two terminal ports of the first 1 × 2 switch is a first output port, and one of the two terminal ports of the second 1 × 2 switch is The terminal port is defined as a second output port, and the other of the two terminal ports of the first 1 × 2 switch and the second
An optical path switch in which a plurality of 2 × 2 switch units connected to the other of the terminal ports are arranged in parallel, a main signal light input to a first input port of a first stage 2 × 2 switch unit of the optical path switch, A first optical circulator for separating the drop signal light output from the port, a first output port and a second input port of each 2 × 2 switch unit of the optical path switch, and a second output port and a next output port; A plurality of optical waveguides respectively connecting the first input ports of the 2 × 2 switch units of the stage; and a plurality of optical waveguides inserted into the optical waveguides connecting the first output port and the second input port of the 2 × 2 switch unit, each of which has a predetermined shape. A plurality of reflective wavelength-selecting elements that reflect signal light of a wavelength and transmit signal light of other wavelengths; and a 2 × 2 switch at the last stage of the optical path changeover switch. And a second optical circulator for separating the main transmitted signal light output from the second output port of the switch unit and the add signal light input to the same port, wherein each of the 2 × 2 switch units of the optical path changeover switch is provided. A wavelength-division multiplexing add / drop apparatus, wherein a path passing through the reflective wavelength selection element or a bypass path is selected according to a state, and an add / drop wavelength is selected. 5. The wavelength-division multiplexing add / drop device according to claim 4, wherein the 1 × 2 switch constituting the 2 × 2 switch unit of the optical path switch includes two orthogonal waveguides and an intersection thereof. A thermocapillary optical switch comprising a groove formed at an angle of 45 degrees with respect to the optical axis of each waveguide, and a refractive index matching oil that slides in the groove by thermal capillary action to switch between total reflection and transmission. A wavelength multiplexing type add / drop device characterized by the following. 6. The wavelength-division multiplexing add / drop device according to claim 4, wherein the 1 × 2 switch constituting the 2 × 2 switch unit of the optical path switch is one movable optical fiber and two fixed lights. A wavelength division multiplexing type add / drop apparatus characterized in that a fiber is opposed to the movable optical fiber, a magnetic substance is applied to the movable optical fiber, and the movable optical fiber is directly opposed to one of the two fixed optical fibers by magnetic driving. . 7. The wavelength multiplexing type add / drop device according to claim 1, wherein the reflection type wavelength selecting element is a grating filter formed in the optical waveguide. Wavelength multiplex type add / drop device. 8. The wavelength-division multiplexing add / drop device according to claim 7, wherein the optical path switching switch, the optical waveguide, and the reflection type wavelength selection element are monolithically integrated on the same substrate. Wavelength multiplex type add / drop device. 9. A wavelength multiplexing add / drop method using the wavelength multiplexing type add / drop device according to claim 1 or 2, wherein the wavelength-multiplexed main signal light is passed through the first optical circulator. Inputting the signal to the first input / output port, selecting a path that passes through or bypasses the reflective wavelength selection element according to a combination of switching states of the 2 × 2 switch of the optical path switch; Taking out the signal light reflected by the selection element through the reverse path to the first input / output port, outputting the signal light as drop signal light separated from the main signal light through the first optical circulator, The transmitted signal light and the signal light bypassing the reflective wavelength selecting element are taken out to the second input / output port as main transmitted signal light, and the second optical circuit A wavelength multiplexing type add / drop method, wherein the output is performed via a comparator. 10. The wavelength-division multiplexing add / drop method according to claim 9, wherein the add signal light having a wavelength equal to one of the wavelengths of the drop signal light output from the first optical circulator is used as the second light. A wavelength-division multiplexing add / drop method, wherein the signal is input to the second input / output port via a circulator, reflected by a corresponding reflection-type wavelength selection element, and multiplexed with the main transmission signal light. 11. The wavelength multiplexing type add / drop method using the wavelength multiplexing type add / drop device according to claim 4, wherein the optical path switching switch multiplexes the wavelength multiplexed main signal light via the first optical circulator. The first input port of the 2 × 2 switch unit of the first stage, and the path that passes through or bypasses the reflective wavelength selection element according to the combination of the switching states of the 2 × 2 switch unit of the optical path switch. The signal light reflected by the reflection type wavelength selection element is taken out to the first input port by a reverse path, and output as a drop signal light separated from the main signal light through the first optical circulator, The signal light transmitted through the reflection-type wavelength selection element and the signal light bypassing the reflection-type wavelength selection element are used as main transmission signal light as the optical path. Replacement extraction to a second output port of the 2 × 2 switch unit in the final stage of the switch, a wavelength multiplexing add-drop method and outputting through the second optical circulator. 12. The wavelength multiplexing add / drop method according to claim 11, wherein the add signal light having a wavelength equal to one of the wavelengths of the drop signal light output from the first optical circulator is used as the second light. The signal is input to a second output port of a 2 × 2 switch unit at the last stage of the optical path switch via a circulator, reflected by a corresponding reflection type wavelength selection element, and multiplexed with the main transmitted signal light. Wavelength multiplex type add / drop method.