JPH08160248A - Optical switch and optical switch group using the same - Google Patents

Abstract

PURPOSE: To attain a number of addresses M larger than a number of available wavelengths N and to provide an optical switch capable of providing M×M communication systems at maximum among a number of terminals M larger than the number of wavelengths. CONSTITUTION: This switch is provided with an optical branching part 131 to which one or plural optical signals are inputted and an optical control part 150 to which one or plural optical signals are inputted, the optical branching part 131 makes only a prescribed optical signal among the inputted one or plural optical signals pass through, at least a part of the prescribed optical signals passed through the optical branching part 131 controls the passage of an optical signal to be inputted to the optical control part 150.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical switch used in an optical system such as an optical computer, an optical switch, an optical CATV and an optical LAN.

[0002]

2. Description of the Related Art One of optical communication systems such as an optical CATV and an optical LAN that multiplexes a plurality of lights having different wavelengths and multiplexes them, and branches them to a plurality of terminals by using an optical switch.
There is something like that shown in The optical communication system shown in FIG. 13 uses optical signals having N kinds of wavelengths to input light 11, 1
2 ... 1N etc. are converted into target wavelengths λ1 (31), λ2 (32), ... λN (3N) etc. by wavelength conversion lasers 21, 22, ... 2N, respectively. The optical signals converted into these target wavelengths are mixed by the optical star coupler 40, and the desired wavelength is selected and extracted by the variable wavelength filters 51, 52, ... 5N on the output side. In the optical communication system of FIG. 13, output side tunable wavelength filters tunable wavelength filters 51, 5
2, ... 5N, etc., is limited to a predetermined fixed wavelength, this system uses N wavelengths of NxN with a maximum number of N terminals assigned one wavelength of each wavelength as the address of that terminal. It can be used as a communication system or an optical switching system. In addition, M described in the present specification and drawings,
The symbols such as N and p and the numbers of the constituent elements are common to the following.

[0003]

The above-mentioned optical communication system uses optical signals having N different wavelengths as addresses, and one address wavelength is assigned to one terminal to make a maximum of N signals.
N × N communication between terminals can be performed. However, in the case where it is required to connect more terminals than the number of usable wavelengths, there is a problem that the above-mentioned conventional optical communication system cannot handle it because the number of wavelengths serving as addresses is insufficient.

The present invention solves the above problems, realizes an address number M that is equal to or greater than the number N of wavelengths that can be used, and enables a maximum M × M communication system within the number M of terminals equal to or greater than the number of wavelengths. It is an object of the present invention to provide an optical switch for.

[0005]

The present invention has the following means in order to solve the above problems.

The optical switch according to claim 1 of the present invention comprises an optical branching unit for inputting a plurality of optical signals and an optical control unit for inputting a plurality of optical signals, wherein the optical branching unit inputs a plurality of optical signals. Of which only a predetermined optical signal is passed,
At least part of the optical signals of the predetermined optical signals that have passed through the optical branching unit controls passage of the optical signal input to the optical control unit.

The optical switch according to the second aspect of the present invention is characterized in that the optical signal input to the optical control unit is the same optical signal as the optical signals input to the optical branching unit.

The optical switch according to a third aspect of the present invention is characterized in that the optical signal input to the optical control unit is a plurality of optical signals different from the plurality of optical signals input to the optical branching unit.

The optical switch according to a fourth aspect of the present invention comprises a wavelength filter to which a plurality of optical signals are input and an optical control unit to which a plurality of optical signals are input, wherein the wavelength filter is one of the plurality of input optical signals. What is characterized in that only a predetermined optical signal is passed, and at least a part of the predetermined optical signals passed through the wavelength filter controls the passage of an optical signal input to the optical control unit. To do.

The optical switch group according to claim 4 of the present invention is
An optical branching unit for inputting a plurality of optical signals and an optical control unit for inputting a plurality of optical signals are provided, wherein the optical branching unit passes only a predetermined optical signal among the plurality of input optical signals, A plurality of optical switches are provided for controlling passage of an optical signal of at least a part of the predetermined optical signals that have passed through the optical branching unit and input to the optical control unit.

[0011]

According to the optical switch of the first aspect of the present invention,
An optical branching unit for inputting a plurality of optical signals and an optical control unit for inputting a plurality of optical signals are provided, and the optical branching unit passes only a predetermined optical signal among the plurality of input optical signals. Since at least a part of the predetermined optical signals that have passed through the branching unit controls the passage of the optical signals input to the optical control unit, for example, N optical switches are arranged for N optical signals. In the case of the optical switch group, each optical switch has one output terminal of the optical branching unit, and therefore the optical switch group has N output terminals.
When the number of optical signals input to the optical control unit by each optical switch is N, for example, the number of output terminals of the optical control unit is N, and the number of output terminals of the optical control unit is N. It has N × (N + 1) output terminals.

According to the optical switch of the second aspect of the present invention, since the optical signal input to the optical control unit is the same optical signal as the optical signals input to the optical branching unit, the optical control unit. If a plurality of optical signals input to the optical switch are N, for example, this optical switch has a maximum of N output terminals.

According to the optical switch of the third aspect of the present invention, the optical signal input to the optical control unit is a plurality of optical signals different from the plurality of optical signals input to the optical branching unit. If a plurality of optical signals input to the optical control unit in addition to the output terminal are N, for example, this optical switch will have a maximum of N plus 1
Will have output terminals.

According to the optical switch of claim 4 of the present invention, the optical switch comprises a wavelength filter to which a plurality of optical signals are input and an optical control unit to which a plurality of optical signals are input. Of the predetermined optical signals that have passed through the wavelength filter, at least a part of the predetermined optical signals controls the passage of the optical signals that are input to the optical control unit. In the case of an optical switch group in which N optical switches are arranged for N optical signals, a plurality of optical signals input to the optical control units of the N optical switches are, for example, N optical switches.
In the case of the number of optical switches, each optical switch has N output terminals, so that the optical switch group has a maximum of N × N output terminals.

According to a fifth aspect of the present invention, there is provided an optical switch group comprising an optical branching unit for inputting a plurality of optical signals and an optical control unit for inputting a plurality of optical signals. Light for passing only a predetermined optical signal of the optical signals, wherein at least a part of the predetermined optical signals that have passed through the optical branching unit controls the passage of the optical signal input to the optical control unit. Since a plurality of switches are provided, for example, in the case of an optical switch group in which N optical switches are arranged for N optical signals, each optical switch can have one output terminal of an optical branching unit. Therefore, the optical switch group can have a maximum of N output terminals, and at the same time, if each optical switch has a plurality of optical signals input to the optical control section, for example, N output terminals, the optical control section can output N output terminals. Since I will have it, I will make it an optical switch group Up will have a N × (N + 1) pieces of output terminals.

[0016]

The present invention will be described below in detail with reference to examples.

(Embodiment 1) An embodiment of the present invention will be described with reference to FIG. In FIG. 1, the optical switch 161 comprises a wavelength filter 121, an optical branching device 131, a drive circuit 141, and an optical control unit 150 having an optical controller 151. For example, when two input lights including the signal components of the input light A and the input light B enter the optical switch 161, and the ON / OFF operation of the optical switch is determined by the wavelength of the input light A. Will be described. The input light A passes through the optical transmission line 181, and enters the wavelength filter 121 in the optical switch 161. Since the wavelength filter 121 passes only a predetermined wavelength that has been set in advance, if the input light A that is incident matches this wavelength, the input light A passes through this wavelength filter 121 and reaches the optical branching device 131. The input light A reaching the optical branching device 131 is branched here, and one of the light beams passes through the optical transmission line 183 and is output as output light A.

On the other hand, the split light 11 split by the optical splitter 131
3 is input to the drive circuit 141 of the light control unit 150. The branched light 113 input to the drive circuit 141 operates the drive circuit 141 to control the light controller 151 (details will be described later). This optical controller 151 controls the input light B that has passed through the optical transmission line 182.
The light controller 151 is controlled to pass through the light controller 151 as it is. The input light B that has passed through the optical controller 151 passes through the optical transmission line 184 and is output as output light B. If the input light A does not match the wavelength filter 121, the input light A is blocked by the wavelength filter 121 and the optical branching device 13
Does not reach 1

Therefore, the light is not output as the output light A, and the drive circuit 141 of the light controller 150 does not operate, and the light controller 1
Since 51 also does not operate, the input light B cannot pass through the light controller 151, and the output light B is also not output. In this way, in the optical switch 161, if the input light A matches the wavelength of the wavelength filter 121, both the input light A and the input light B pass through the optical switch 161. However, if the input light A does not match the wavelength filter 121, neither the input light A nor the input light B passes through the optical switch 161.

It should be noted that since it is only necessary to extract a part of the input light A from the optical branching device 131, leakage light of the input light A or the like may be used instead of the optical branching device. Further, in applying the optical switch to a system in which the optical switch is turned on / off depending on whether there is the input light A of the optical switch, the optical switch is a wavelength filter.
121 is not absolutely necessary.

FIG. 2 shows a specific example of the light control section 150 shown in FIG. The drive circuit 141 shown in FIG.
The part other than 1, the laser amplifier 251 in FIG. 2 is an example of the optical controller 151 in FIG. The drive circuit 141 is a DC power supply 221,
Light receiving element 261, resistor A222, resistor B223, transistor
231 and ground 241.
The input light A211 shown in FIG. 2 corresponds to the branched light 113 in FIG. 1, and the input light B212 corresponds to the input light B112 in FIG. The output light 292 in FIG. 2 corresponds to the output light B in FIG.

In FIG. 2, the input light A 211 is the light receiving element 26.
When it is incident on 1, a current corresponding to the input light A211 flows through the light receiving element 261. Part of that current 281 is transistor 231
Is turned on, the transistor 231 is turned on, and a current 282 also flows through the laser amplifier 251. As a result, the laser amplifier 251 is also turned on, and its input light B212 is optically amplified and output as output light 292. On the other hand, input light A211
If there is no light, no current flows from the light receiving element 211, so that the transistor 231 does not operate and remains off. Therefore, the current 282 does not flow in the laser amplifier 251, so that the laser amplifier 251 also remains off. As a result, the input light B212
Cannot pass through the laser amplifier 251, so that nothing is output to the output light 292. As described above, the drive circuit 141 optically amplifies the input light B212 when the input light A211 enters, and outputs it as the output light 292. However, if the input light A211 does not enter, no input light B212 is output. . The above is the operation of the drive circuit 141.

Further, instead of the laser amplifier 251, an optical fiber amplifier, an optical shutter, a liquid crystal or the like can be used. FIG. 3 shows an example of an optical switch 361 using an optical shutter 351 instead of the laser amplifier. The operation of FIG. 3 is the same as that of FIG. 2 except that the laser amplifier 251 in FIG. 2 is replaced by the optical shutter 351 in FIG. 2, so that the detailed description thereof will be omitted. Since the other configurations are the same as those in FIG. 1, the same members are designated by the same reference numerals and detailed description thereof will be omitted. The same applies when a liquid crystal is used instead of the optical controller, but when an optical fiber amplifier is used, it has an optical amplifying action as in the case of the laser amplifier 251.

(Embodiment 2) FIG. 4 shows another embodiment of the optical switch of the present invention. In this embodiment, both the input light A 411 and the input light B 412 pass through the optical switch 461 and output optical signals are output from the optical switch 461. Laser amplifier A45 respectively
1 and a laser amplifier B452 are inserted. As a result, the output light A491 and the output light B492 are output in the same optical amplified state. The drive circuit B442 is for driving the laser amplifier B452, and its configuration is shown in FIG.

In FIG. 5, the input light 512 corresponds to the optical signal after passing through the wavelength filter 421 of FIG. 4, and the output light 592 corresponds to the optical signal after passing through the laser amplifier B452. In FIG. 5, a current is constantly flowing through the resistor C524 and the resistor A222, and a part of the current 581 flows to the transistor 231, so that the transistor 231 is always in the ON state. As a result, the current 582 always flows through the laser amplifier B452, so that the laser amplifier B452 is always in the operation (ON) state. Thus, this optical switch 461
If there is 512, it will be optically amplified and output as output light 592,
Output light 592 is not output without input light 512. FIG.
The drive circuit A441 and the laser amplifier A451 of FIG. 2 have the same configuration as that of FIG. 2, and the operation thereof is the same as that of FIG. In addition,
As for the part of the optical branching device 431, only a part of the light of the input light A 411 needs to be extracted.
It is also possible to use leakage light of light passing through the laser 411 or the laser amplifier B452. The other components of FIG. 4, such as the wavelength filter 421 and the optical branching device 431, operate in the same manner as in FIG.

Further, this optical switch 461 has an input light A411.
In applying the optical switch 461 to a system in which the optical switch 461 is turned on / off depending on whether the optical switch 461 is present or absent, the optical switch 461 does not necessarily require the wavelength filter 421. Laser amplifier A451
An optical fiber amplifier may be used instead of the laser amplifier B452.

(Embodiment 3) Another embodiment is shown in FIG. In this example, although there are two input lights,
Only one of them passes through the optical switch. In FIG. 6, the optical switch 661 comprises a wavelength filter 621, a drive circuit 641 and an optical controller 651. The input light A611 is incident on the wavelength filter 621 through the optical transmission line 681. If the wavelength of the incident input light A611 matches the preset wavelength of the wavelength filter 621, the input light A611 passes through the wavelength filter 621 and reaches the drive circuit 641.

When the drive circuit 641 receives the optical signal, it drives the optical controller 651 to operate (turn on) the optical controller 651. When the light controller 651 operates (turns on), input light B612
Passes through light controller 651. As a result, the input light B612 passes through the optical switch 661 and is output as output light B692. On the other hand, if the wavelength of the input light A611 does not match the wavelength preset by the wavelength filter 611, the input light A611 cannot pass through the wavelength filter 621, and the drive circuit 641 does not operate. Therefore, since the light controller 651 also remains off, the input light B612 cannot pass through the light controller 651.

As described above, the optical switch 661 has the input light A
If 611 matches the wavelength preset in the wavelength filter 621, the input light B612 is output as output light B692, but if the input light A611 does not match the wavelength preset in the wavelength filter 621, the optical switch 66
1 does not pass the input light B612. A laser amplifier, an optical fiber amplifier, an optical shutter, a liquid crystal, or the like can be used as the light controller 651. Light controller
Optical switch 761 when laser amplifier is used as 651
The configuration of is shown in FIG. The drive circuit 641 and the laser amplifier 751 in this case have the same configurations as in FIG. 2 and their operations are also the same as in FIG. Here, the input light A711 is the input light A611 of FIG.
And the output light B792 corresponds to the output light B692 in FIG. Also, input light A611,711 of this optical switch 661,761
In applying this optical switch 661,761 to a system in which the optical switch is turned on / off depending on whether or not there is a wavelength filter 621 as the optical switch 661,761.
Is not always necessary.

Next, an example of the configuration of an optical communication system using the optical switch of the present invention as an optical switch group will be described with reference to FIG. For convenience of explanation, the conditions are set as follows. Assuming that the number N of usable wavelengths is 10 and the number of terminals M to be connected is 100 terminals, 100 × 1
00 communication system. Since only 10 types of wavelengths can be used in the conventional technique, the maximum number of connectable terminals is 10. Therefore, the limit is to construct a 10 × 10 communication system.

In the communication system of this example, 100 addresses are required in order to connect 100 terminals with 10 usable wavelengths. To realize this, two wavelengths λA and λB are used. Since each of them can take 10 kinds of wavelengths, a maximum of 100 address wavelengths can be made by combining these. By the way, by combining three wavelengths, a maximum of 1000 addresses can be created, and by using the optical switch of the present invention, 1000 × 100.
A communication system of 0 can be constructed. Since two wavelengths are used here, at least two optical signals are required. These optical signals can be multiplexed and transmitted on a single optical transmission line, but here, in order to simplify the explanation, 2
A case will be described in which one optical signal uses one optical transmission line.

Further, the optical signal and the optical transmission line for data transmission can be provided separately from the optical signal and the optical transmission line for the address wavelength, but here, for simplification of description, the data signal is the address wavelength λA, Description will be made assuming that each optical signal of λ B is transmitted as a modulation signal using the carrier as a carrier. Therefore, in FIG. 8, the number of spatially multiplexed optical transmission lines is two each. However, in general, the address wavelength signal and the data signal may be separately transmitted, and in this case, the number of spatially multiplexed optical transmission lines is generally p. Also, the address wavelength λA
Will be referred to as a first address wavelength, and the address wavelength .lambda.B will be referred to as a second address wavelength.

In FIG. 8, the optical transmitter 811 has two variable wavelength modulators inside (details will be described later with reference to FIG. 9), and the first address wavelength is the destination address of the destination terminal to be transmitted independently. The wavelengths are set to λA and the second address wavelength λB, and the data signal to be transmitted is modulated and transmitted to the two optical transmission lines of the optical transmission line 821. Optical transmission line in FIG.
821 The diagonal lines in other optical transmission lines indicate that there are a plurality of transmission lines, and the symbol p in the middle thereof indicates that the number of parallel transmission lines is p. Note that p represents the number of parallel transmission lines in general. In the example of FIG. 8, the number p of parallel optical transmission lines is two. Optical transmitters 812, 81m etc. are also optical transmitters
Similar to 811, the number of optical transmitters required is M, and there are 100 optical transmitters in total.

The optical signal transmitted to the optical transmission line 821 is input to the optical branching unit 831. The optical branching unit 831 (details of which will be described later with reference to FIG. 10) receives the optical signals input thereto by N optical transmission lines.
The optical transmission lines 8211 to 821n are branched to 8211 to 821n, and these optical transmission lines 8211 to 821n are optical switches 1-1-1 and 1-N in the optical switch 1-1 group.
It is connected to N optical switches, such as optical switches 1-N-1 in the group. The optical signal transmitted to the optical transmission line 82m is also input to the optical branching unit 83m.

The optical branching unit 83m has the same structure as that of the optical branching unit 831. The optical signal input thereto is converted into N optical transmission lines 82m1 to 82m.
mn, and each of these optical transmission lines 82m1 to 82mn is an optical switch 1-
It is connected to N optical switches such as optical switch 1-1-M in group 1 and optical switch 1-NM in group 1-N.
The optical switch 1-1-1, etc. referred to here are the optical switches of the present invention. The optical switch 1-1 group is a set of M optical switches 1-1-1 to 1-1-M. All the optical switches 1-1-1 to 1-1-M in this optical switch 1-1 group are the first address wavelength λ of the input optical signal.
Only A having a wavelength λ1 has a function of transmitting all optical signals combined with the optical signal and outputting the optical signal to the optical transmission lines 8311 to 831m, respectively.

The optical switch 1-1 group also has a function of preventing an optical signal whose first address wavelength λA is not wavelength λ1 from passing through this optical switch. Optical switch 1-1
The M optical switches 1-1-1 to 1-1-M in the group independently perform the same operation. Also, optical switch 1-
Similarly for N group, M of optical switch 1-N-1 to optical switch 1-NM
It is a set of individual optical switches. All the optical switches 1-N-1 to 1-NM in this optical switch 1-N group have only the input optical signal with the first address wavelength λA of wavelength λN combined with the optical signal. It has a function of transmitting all optical signals and outputting the optical signals to the optical transmission lines 83n1 to 83nm, respectively.

The optical switch 1-N group also has a function of preventing an optical signal whose first address wavelength λA is not the wavelength λN from passing through this optical switch. Optical switch 1-N
The M optical switches 1-N-1 to 1-NM in the group independently perform the same operation. The first address wavelength selecting unit 876 has N optical switch groups for controlling an optical signal by such a first address wavelength, and N wavelengths λ1 to λN are assigned to the first address wavelength, respectively. . The optical signals output to the optical transmission lines 8311-831m are input to the optical star coupler unit 881 (details will be described later with reference to FIG. 11).

The optical signals coming from the optical transmission lines 8311-831m are mixed therein for each of the first address wavelength signal and the second address wavelength signal and output to the optical transmission lines 8511-851n. this is,
The same applies to the optical star coupler unit 88n and the like. The optical signals mixed by the optical star coupler unit 881 are N in the optical switch 2-1 group.
Input to each optical switch. In the N optical switches of the optical switches 2-1-1 to 2-N, the second address wavelength λB is set and set for each of the N wavelengths of wavelengths λ1 to λN for each optical switch. Only when the same wavelength as the second wavelength is input as the second address wavelength, the combination of the optical signals is passed. Optical switch
2-1-1 allows only the second address wavelength λB having the wavelength λ1 to pass, and blocks the others.

The optical switch 2-1-2 has the second address wavelength λB.
Pass only those with wavelength λ2 and block others. In the optical switch 2-1-N, the second address wavelength λB is the wavelength λ
Only N's are allowed to pass and the others are blocked. Similarly, in the optical switch 2-N group, the optical signals mixed in the optical star coupler unit 88n are input to N optical switches in the optical switch 2-N group. In the N optical switches 2-N-1 to 2-NN, the second address wavelength .lambda.B is set to each of the N wavelengths .lambda.1 to .lambda.N for each optical switch. Only when the same wavelength as the set wavelength is input as the second address wavelength, the combination of the optical signals is passed. For example, the optical switch 2-N-1 allows only the second address wavelength .lambda.B having the wavelength .lambda.1 to pass and blocks the others.

The optical switch 2-N-2 has the second address wavelength λB.
Pass only those with wavelength λ2 and block others. In the optical switch 2-NN, the second address wavelength λB is the wavelength λ
Only N's are allowed to pass and the others are blocked. In the second address wavelength selection unit 877, there are N such optical switch groups in total.

The optical signal passing through the second address selecting unit 877 passes through the optical transmission paths 8411, 841n, 84n1, 84nn, etc., and reaches the intended optical receivers 8911, 891n, 89n1, 89nn, etc. For example, an optical signal emitted from a combination of wavelength addresses (λ1, λ1) reaches the optical receiver 8911.

Further, the optical signal emitted by the combination of the wavelength addresses (λN, λN) reaches the optical receiver 89nn. There are M optical receivers in total, and there are 100 optical receivers in the present description, and one optical transmitter is paired with one optical transmitter as shown in FIG. As described above, the optical switch of the present invention enables a 100 × 100 optical communication system between 100 terminals despite the use of 10 wavelengths.

FIG. 9 shows the internal structure of the optical transmitter 811 and the optical transmission line.
It shows the relationship with 821. In FIG. 9, data to be transmitted is accumulated in transmission buffers 911 and 912 and sent to the variable wavelength modulators 931 and 932 under the control of the access control unit 921. The variable wavelength modulators 931 and 932 respectively set the first address wavelength λA941 and the second address wavelength λB942 in accordance with the address of the terminal of the other party to be transmitted under the control of the access control unit 921, and modulates the data signal to transmit the light. It sends light to the 821.

FIG. 10 shows the structure of the optical branching unit 831. The optical branching unit 831 is composed of p optical branching devices that branch one input signal into N optical transmission lines. FIG. 10 shows the configuration when p is 2. The optical branching unit 831 is the optical transmission line 82.
1 to N optical splitters 10 for receiving 1 p optical transmission lines, respectively
Enter in 11 and 1012. The optical splitters 1011 and 1012 split the input optical signals into N optical transmission lines, and further combine the optical transmission lines output from the optical splitters 1011 and 1012 into two optical transmission lines. It connects to the transmission path 8211 or 821n. The optical transmission lines 8211 to 821n on the output side in FIG. 10 indicate that there are N sets of optical transmission lines each having two sets.

FIG. 11 shows the structure of the optical star coupler unit 881. The optical star coupler unit 881 has p M to N optical star couplers for mixing and distributing M sets of optical inputs to N sets of optical outputs. FIG. 11 shows the case where p is 2. The optical star coupler unit 881 has optical transmission lines 8311 to 83.
Using 1m as an input signal, optical star couplers 1111 and 1112 mix and distribute for each address wavelength, and combine the transmission lines that are the outputs of each optical star couplers 1111 and 1112 into two optical signals. It is output to the transmission lines 8511 to 851n.

FIG. 12 shows the structure of the terminal.
The terminal 1211 includes an optical transmitter 811, an optical receiver 891, and a controller 1221. The control unit 1221 receives the data 1231 from the outside, converts it into an optical signal at the optical transmitter 811 and converts it to the optical transmission line 82.
Send to 1. On the other hand, the optical receiver 891 receives the optical signal from the optical transmission path 8411, demodulates it into an electric signal, and transmits it to the control unit 1221. The control unit 1221 transmits the data 1231 to the outside. It should be noted that the optical receiver 891 has two light receiving devices, which correspond to the two optical transmission lines 3411 respectively.

As described above, the optical switch of the present invention and the optical switch group using the optical switch constitute an optical communication system for connecting more terminals than the number of usable wavelengths, which has been impossible in the past. You can

[0048]

As described above, by using the optical switch of the present invention and the optical switch group using the same, an optical communication system for connecting a number of terminals of which the number of usable wavelengths is greater than that which has hitherto been impossible. Can be built. According to the optical switch of claim 1 of the present invention, the optical switch includes an optical branching unit for inputting one or more optical signals and an optical control unit for inputting one or more optical signals, and the optical branching unit inputs Of the one or more optical signals, only a predetermined optical signal is passed, and at least a part of the predetermined optical signals that have passed through the optical branching unit is input to the optical control unit. Since the passage is controlled, for example, in the case of an optical switch group in which N optical switches are arranged for N optical signals, each optical switch has one output terminal of the optical branching unit, and therefore the optical switch group is provided. Has N output terminals and, at the same time, when each optical switch inputs a plurality of optical signals to the optical control section, for example, N, it has N output terminals for the optical control section. Has a maximum of N × (N + 1) output terminals It is possible.

According to the optical switch of the second aspect of the present invention, the optical signal input to the optical control unit is input to the optical branching unit.
This optical switch has a maximum of N output terminals if the plurality of optical signals input to the optical control unit are, for example, N since they are the same one or a plurality of optical signals as one or a plurality of optical signals. be able to.

According to the optical switch of the third aspect of the present invention, the optical signal input to the optical control unit is input to the optical branching unit.
Since it is one or a plurality of optical signals different from one or a plurality of optical signals, if the plurality of optical signals input to the optical control unit in addition to the output terminal of the optical branching unit are N, for example, this optical switch is maximum. Can have N plus 1 output terminal.

According to the optical switch of claim 4 of the present invention, a wavelength filter to which one or a plurality of optical signals are input and an optical control unit to which one or a plurality of optical signals are input are provided, and the wavelength filter is an input. Of the one or more optical signals, only a predetermined optical signal is allowed to pass, and at least a part of the predetermined optical signals that have passed through the wavelength filter are input to the optical control unit. Because it controls the passage
For example, in the case of an optical switch group in which N optical switches are arranged for N optical signals, when the plurality of optical signals input to the optical control unit of the N optical switches are N, the respective optical switches Since N has N output terminals, the optical switch group can have a maximum of N × N output terminals.

According to the optical switch group of the fifth aspect of the present invention, an optical branching unit to which one or a plurality of optical signals are inputted and one
An optical control unit to which one or a plurality of optical signals are input is provided, and the optical branching unit allows only a predetermined optical signal of the input one or a plurality of optical signals to pass, and the predetermined optical signal to pass through the optical branching unit. Of the optical signals, at least a part of the optical signals has a plurality of optical switches for controlling the passage of the optical signals input to the optical control unit. Therefore, for example, N optical switches for N optical signals. In the case of the optical switch group in which the optical switches are arranged, each optical switch can have one output terminal of the optical branching unit, so that the optical switch group can have a maximum of N output terminals and at the same time each optical switch has If a plurality of optical signals input to the optical control unit are N, for example, the optical control unit has N output terminals. Therefore, the optical switch group may have a maximum of N × (N + 1) output terminals. it can.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of an optical switch of the present invention.

FIG. 2 is a circuit diagram showing an example of an optical control unit of the optical switch shown in FIG.

FIG. 3 is a configuration diagram showing another embodiment of the optical switch of the present invention.

FIG. 4 is a configuration diagram showing another embodiment of the optical switch of the present invention.

5 is a circuit diagram showing an example of a laser amplifier of the optical switch shown in FIG.

FIG. 6 is a configuration diagram showing another embodiment of the optical switch of the present invention.

FIG. 7 is a configuration diagram showing another embodiment of the optical switch of the present invention.

FIG. 8 is a configuration diagram showing an example of an optical communication system using the optical switch and the optical switch group of the present invention.

9 is a configuration diagram showing an example of an optical transmitter of the optical communication system of FIG.

10 is a configuration diagram showing an example of an optical branching unit of the optical communication system of FIG.

11 is a configuration diagram showing an example of an optical star coupler of the optical communication system of FIG.

12 is a configuration diagram showing an example of a terminal unit of the optical communication system of FIG.

FIG. 13 is a configuration diagram showing an example of a conventional optical communication system.

[Explanation of symbols]

 131 Optical Branching Unit 141 Drive Circuit 150 Optical Control Unit 151 Optical Controller 161 Optical Switch 721 Wavelength Filter 761 Optical Switch

Claims (5)

[Claims] 1. An optical branching unit for inputting one or a plurality of optical signals and an optical control unit for inputting one or a plurality of optical signals, the optical branching unit for inputting one or more optical signals. Of the predetermined optical signals that have passed through the optical branching unit, at least a part of the optical signals that pass through the predetermined optical signals are controlled to control the passage of the optical signals that are input to the optical control unit. Characteristic optical switch. 2. The optical signal according to claim 1, wherein the optical signal input to the optical control unit is the same optical signal as the optical signal input to the optical branching unit. switch. 3. The optical switch according to claim 1, wherein the optical signal input to the optical control unit is one or a plurality of optical signals different from the one or a plurality of optical signals input to the optical branching unit. . 4. A wavelength filter to which one or a plurality of optical signals are input, and an optical control unit to which one or a plurality of optical signals are input, wherein the wavelength filter is a predetermined one of the input one or a plurality of optical signals. Of the predetermined optical signals that have passed through the wavelength filter, and controls the passage of at least some of the optical signals that are input to the optical control unit. Optical switch. 5. An optical branching unit to which one or a plurality of optical signals is input and an optical control unit to which one or a plurality of optical signals are input, wherein the optical branching unit is for inputting one or more optical signals. An optical switch that allows only a predetermined optical signal to pass therethrough, and controls the passage of an optical signal in which some of the predetermined optical signals that have passed through the optical branching unit are input to the optical control unit. An optical switch group having a plurality of optical switches.