JPH11295529A - Adjuster for equalizing length of optical fiber and adjustment method for equalizing length of optical fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adjuster for equalizing the length of optical fibers capable of highly accurately equalizing the length of the optical fibers by simple constitution. SOLUTION: A delay waveguide group 06 composed of plural delay waveguides 061-06n respectively, different in optical path lengths is formed on a waveguide substrate 01, the delay waveguide group 06 and an input side optical fiber 02 are connected through an input side branching part 04 and the delay waveguide group 06 and an output side optical fiber 03 are connected through an output side joining part 05. The input side branching part 04 and the output side joining part 05 function as optical switches and by selecting the delay waveguide provided with an optimum delay amount from the plural delay waveguides 061-06n, fiber errors generated at the time of manufacturing a fiber connector are absorbed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber amplifier in the field of optical fiber communication, and more particularly, to an optical fiber amplifier in which transmission delay times of optical signals transmitted in parallel via a plurality of optical fibers are equal between the optical fibers. The present invention relates to a controllable optical fiber equalization adjuster and an optical fiber equalization adjustment method.

[0002]

2. Description of the Related Art Optical ATM exchanges that utilize the high speed and broadband characteristics of light to further improve the throughput over conventional electronic exchanges are being studied. In such an optical ATM exchange, a function as an exchange is realized by switching an optical cell in which a data cell serving as an information processing unit is converted into an optical signal using an optical switch capable of operating at high speed.

A cell type or packet type optical signal is used in such an optical ATM switch or a large capacity optical switch for application to connection between a processor of a supercomputer or between a processor and a memory.
For this reason, since an optical signal having a discontinuous clock phase arrives at the optical receiver provided at the optical switch output unit, the optical receiver needs to have a function of receiving the signal. At this time, the connection of the optical switch is switched for each cell (or for each packet) in a time of about several nsec, which is sufficiently shorter than the cell length (or the packet length). Therefore, the technique of extracting a high-speed clock from a preamble portion of a packet used in a conventional packet-type transmission line cannot be applied.

[0004] In order to perform error-free reception of a cell-type optical signal accompanied by switching in such a short time as about several nsec, all optical fiber paths from a transmitter to a receiver inside the optical switch must be provided. It is necessary to make the transmission path lengths of the optical signals all equal and to suppress the skew which causes the clock phase difference of the cells sufficiently small. For this reason, it is required that the length of the fiber used for the optical component constituting the optical switch be made equal in length with high accuracy.

As an example of such equalization, there is an optical fiber equalization adjuster described in FIG. 1 of the IEICE Communications Society Conference 1996, B-1076. In this optical fiber equalization adjuster, “Delay L
A variable optical delay line indicated as “ine” is inserted as an optical fiber length adjuster, and the length of the fiber in each path is equalized. In this example, 10G per route
In transmitting an optical signal of bps, if the skew allowed for good optical reception with the same clock is set to 10% or less of the width of one bit (100 psec), the skew needs to be suppressed to 10 psec or less. is there. The propagation delay in the optical fiber is about 5 nsec / m. This is equivalent to 2 mm when converted to an optical fiber length.

Further, inside these optical ATM exchanges and supercomputers, several Gbps used for these are used.
In order to connect more than s high-speed signals between boards or frames, a parallel transmission type optical interconnection technology is essential. For the transmission path of such a parallel transmission type optical interconnection, an array fiber in which a plurality of fibers are bundled in a tape shape is used for the purpose of ease of assembly and reduction of mounting volume.

Then, in order to realize parallel transmission with low skew, a plurality of array fibers are collectively subjected to end face processing. For this reason, it is promising in that relatively equal lengths are relatively easy. Further, in order to compensate for the loss of light intensity due to fiber loss or signal branching, Japanese Patent Laid-Open No. 7-162 is disclosed.
As described in JP-A-364, an array fiber using a fiber amplifier to which rare earth ions are added can also be used.

However, in the current production of connectors at the ends of optical fibers or the fusion splicing technique between ends of optical fibers, it is inevitable that a certain degree of error occurs in both single-core fibers and array fibers. For example, as production accuracy,
Unless an error of 1 to 2 cm is observed with respect to the entire length, the yield is deteriorated and the cost is increased due to damage due to end face polishing and generation of bubbles at the time of fusion. Therefore, it is very easy to equalize only the array fibers, but it is extremely difficult to equalize different array fibers from each other due to the problem of manufacturing accuracy. That is, although relative length accuracy can be ensured, it has been difficult to satisfy absolute length accuracy at low cost.

When the above-mentioned array fiber amplifier to which rare earth ions are added is used, an optical coupler used as a converging element for excitation light is required for each fiber outside the array section. For this reason, when the array fiber is finally made equal in length, a fiber length adjuster is required again, and the advantage of the equal length and the downsizing by using the array fiber cannot be utilized.

[0010]

That is, the conventional optical fiber length adjuster has the following problems. A first problem is that suppressing the skew between paths causes an increase in cost for an optical switch used for transmitting an optical signal of a class exceeding several Gbps used inside an optical ATM switch or the like.

[0011] The reason for this is that at the time of current optical connector manufacturing, an error of about several mm to about 2 cm occurs with respect to the entire length of the optical fiber. This error is caused by an error of several millimeters caused by shrinkage or misalignment during curing of the adhesive used for connectorizing, and an error of about 1 cm caused by cutting the end of the optical fiber due to damage during polishing of the connector end face. It consists of shortening the total length. Due to such causes, for example, 1
In order to realize the fiber length accuracy of 2 mm required when handling 0 Gbps optical signals, it is unavoidable that the cost increase due to the low yield at the time of producing the fiber cable increases.

The second problem is that the optical components used for fine-tuning the skew suppression inside the optical switch for transmitting optical signals of several Gbps or more increase the total volume of the delay adjuster and reduce the cost. To rise and cause. As a variable optical delay adjuster for correcting a delay amount between different optical fiber paths, for example, there is a mechanical variable optical delay adjuster as shown in FIG. The variable optical delay adjuster shown in FIG. 17 includes a fixed collimator lens 70, an input optical fiber 71 connected to the fixed collimator lens 70, and a movable collimator lens 70 which is disposed to face the fixed collimator lens 70. A collimating lens 72, an output optical fiber 73 connected to the movable collimating lens 72, and a collimating lens moving mechanism 74 for moving the movable collimating lens 72 in the axial direction with respect to the fixed collimating lens 70.
And The collimating lens moving mechanism 74 is
A base 75 extending in the moving direction of the movable collimating lens 72, a moving shaft 76 supported on the base 75, and having a thread cut on the outer periphery, and a movable shaft 76 that is screwed into the moving collimating lens 72. And a supporting block 77 which supports the supporting block.

In this variable optical delay adjuster, by rotating the moving shaft 76, the movable collimating lens 72 moves in a desired direction in a desired distance according to the rotation direction and the rotation angle. The movement of the movable collimating lens 72 corrects the amount of delay between the fiber paths. However, this variable optical delay adjuster requires a volume for accommodating the collimating lens moving mechanism 74 itself and a volume for securing a moving range of the moving shaft 76, and thus the overall size of the delay adjuster is increased. Unavoidable. Further, the cost is increased by the amount required to manufacture the collimating lens moving mechanism 74.

A third problem is that when the variable optical delay adjuster shown in FIG. 17 is used, not only the component cost increases, but also the adjustment cost required for performing equal length increases. is there. The reason is that in order to perform equal length using the variable optical delay adjuster, it is necessary to adjust the variable optical delay adjuster for each optical path after assembling all the optical paths from the start point to the end point. is there. The main reason is that, as described in the first problem, it is difficult to make the length equal at the optical component level separated by the optical connector.

FIG. 18 shows an example in which each optical path is assembled and adjusted. FIG. 1 is a block diagram of an example of the variable optical delay adjuster. Wavelength DEMUX80 and Wavelength MUX81
Are connected by a plurality of optical waveguides, and each optical waveguide incorporates an optical gate 82 and a delay adjuster 83, respectively. The signal of several Gbps emitted from the signal generator 84 is received by the multi-wavelength optical transmitter 85, and the multi-wavelength optical transmitter 85 multiplexes the wavelength-division multiplexed signal light according to the wavelength DEMU.
Send to X80. After passing through one optical waveguide, this wavelength multiplexed signal light is output from the wavelength MUX 81 to the optical signal receiver / phase comparator 86 as a selection signal light.

In the variable optical delay adjuster shown in FIG. 18, an optical signal conforming to an actual operation is transmitted to an active component such as an optical amplifier (not shown) and an optical gate 82 inserted into an optical path, It is necessary to transmit an optical signal such as the wavelength MUX81, the wavelength DEMUX80, or an optical filter (not shown) to a component having a wavelength characteristic in advance. For this reason, it is necessary to control the output intensity and wavelength of the optical signal transmission source for adjustment or the optical signal modulation method.

As described above, it is necessary for the optical signal used in the optical path length adjustment to satisfy the specifications of each delay adjuster. As a result, a cost reduction effect by mass production cannot be expected for an optical component such as an optical fiber cable that does not depend on light intensity or wavelength, as compared with a case where adjustment at a component level is possible. The fourth problem is that
Even when the array fiber doped with rare earth ions is used, if the entire optical signal transmission path including the converging portion of the excitation light is to be made equal in length, the variable optical delay adjuster is used. And cost increases.

The reason is that each fiber must be divided into a single core since a fusion type optical coupler is used in a portion where a rare earth ion is added to an excitation light converging portion of the fiber. The single-core fused optical coupler and the rare-earth ion-doped fiber are connected by a connector or connected by fiber fusion (splice). Here, as for the connection by the connector, as described in the first problem, an error in the fiber length caused by the manufacturing accuracy of the connector becomes an obstacle to equal length. Also, in splicing by fiber fusion, it is impossible to completely avoid the occurrence of bubbles at the splicing point and an increase in loss due to misalignment, and there are also several cm cuts at the fiber end due to fusion failure. Therefore, there is the same obstacle to equal length as the problem in the connection by the connector. For this reason, even if it is possible to equalize a part of the fiber by adding an array of fibers to which rare earth ions are added, there is no improvement in terms of the entire optical signal path.

In addition to the above-mentioned conventional variable optical delay adjuster,
Japanese Unexamined Patent Publication No. 3-268630 discloses a line between a first switching point and a second switching point of an optical fiber transmission line.
An optical fiber line switching method for switching to a switching line while maintaining the synchronization state of an optical signal by compensating for a change in delay time has been proposed. In addition, Japanese Patent Application Laid-Open
No. 221708 proposes an ATM cell synchronization method and apparatus for compensating for a delay due to a possible difference in an optical path in a node by utilizing dispersion dependency in an optical fiber with respect to a wavelength.

Furthermore, Japanese Patent Application Laid-Open No. Hei 9-218314 proposes an optimum dispersion compensator for a submarine optical fiber cable in which the amount of dispersion compensation can be selected. However, none of the devices or methods proposed in these publications can solve the above-mentioned problems, in particular, the first and third problems, and sufficiently achieve the equal length of the optical fiber. Not something you can do.

The present invention has been made in view of the above-mentioned problems in the prior art, and reduces the cost of parts required for skew suppression in an optical switch for transmitting an optical signal of a class exceeding several Gbps. It is an object of the present invention to provide an optical fiber equalization adjuster and an optical fiber equalization adjustment method which can increase the yield in assembling a connector of a fiber cable whose length is precisely specified.

Further, according to the present invention, an optical fiber capable of realizing the equal length of the order of 1 mm with respect to the transmission path of an optical signal of a class exceeding several Gbps without using a fine adjustment mechanism and realizing a miniaturization of a delay adjuster. An object of the present invention is to provide an equalization length adjuster and an optical fiber equalization length adjustment method device. Further, the present invention provides an optical fiber equalization adjuster and an optical fiber equalization adjustment method that can realize a reduction in adjustment cost by performing equalization of fiber cables in a parallel transmission portion at a component level. The purpose is to do.

[0023]

To achieve this object, an optical fiber equalization adjuster according to the present invention comprises a plurality of delay guides having different optical path lengths between an input waveguide and an output waveguide. An optical fiber is made equal in length by setting a wave path, selecting only one delay waveguide having an optimum delay time, and transmitting signal light through the delay waveguide.

Specifically, claim 1 of the present invention is as follows.
An optical fiber equalization controller comprising a waveguide substrate and an optical waveguide circuit formed on the waveguide substrate, wherein the optical waveguide circuit includes a plurality of delay waveguides having different optical path lengths. Optical fiber equalization comprising a group of waveguides, an input connection for connecting the group of delay waveguides and the input optical fiber, and an output connection for connecting the group of delay waveguides and the output optical fiber. Provide a regulator.

The difference in the optical path length between the delay waveguides may be formed as the difference in the path length of the delay waveguide, or may be formed as the difference in the refractive index. Is also good. In this case, in order to change the refractive index, it is preferable to provide a heater for heating the delay waveguide and reversibly changing the refractive index, as described in claim 4.

The number of waveguides constituting the delay waveguide group is determined as a function of an error in the length of the optical fiber to be absorbed, as described in claim 3. As described in claim 5, in each of the delay waveguides constituting the delay waveguide group, a transmission amount adjusting region for adjusting the transmission amount of the optical signal is formed, and the input side connection portion is formed by these input side connection portions. It is desirable that the transmission amount adjustment region be adjusted so that the optical signal can pass through only one delay waveguide.

Also, as described in claim 6,
One or both of the input side waveguide and the output side waveguide can be composed of a waveguide doped with rare earth ions. In this case, the optical fiber equalization adjuster includes a pump light source that emits pump light for exciting the input waveguide or the output waveguide, and a merger that merges the pump light with the input waveguide or the output waveguide. , And the merger is preferably formed on a waveguide substrate.

According to a seventh aspect of the present invention, means for selecting a signal light path is provided in one or both of the input side connection part and the output side connection part and / or at least one of the delay waveguides. preferable. The path selecting means selects one delay waveguide having an optimum delay time from the delay waveguide group, and transmits signal light from the input waveguide to the output waveguide via the delay waveguide. Thereby, it functions to adjust the transmission delay time of the signal light.

Further, by measuring a transmission delay time of an optical signal in a fiber patch cord in which a fiber equalizing module is incorporated, an optimum delay waveguide is selected from a plurality of delay waveguides, and a waveguide constituting an optical switch is selected. The optical path can be trimmed to fix the optical switch.
Specifically, for example, as described in claim 8, one or both of the input side connection part and the output side connection part are:
An optical switch that can change the path passing through the delay waveguide according to the change in the refractive index of the waveguide can be used.

Alternatively, as described in claim 9, one or both of the input side connection part and the output side connection part are:
It consists of an optical switch that selects the only path with the optimum amount of delay by trimming from a plurality of connections already established between the input side waveguide or output side waveguide and the delay waveguide group. be able to. Further, as described in claim 10, one or both of the input-side connection part and the output-side connection part select only one connection with an optimum delay amount from the delay waveguide group, and Alternatively, an optical switch that forms a waveguide by trimming an output-side waveguide can be used.

[0031] Further, as set forth in claim 11, one or both of the input side connection part and the output side connection part are:
It is preferable that the optical switch be of a type in which the state is constantly maintained after the path of the optical signal is changed. One or both of the input side connection part and the output side connection part are defined in claim 12.
As described in (1), a 1 × n optical switch can be configured as connected in multiple stages.

As set forth in claim 13, the delay waveguide group may be configured as a series combination of a coarse adjustment delay waveguide and a fine adjustment delay waveguide having different unit delay times. It is possible. The present invention also provides an array-type optical fiber equalization adjuster using the optical fiber equalization adjuster described above.

For example, a fourteenth aspect of the present invention is the above-mentioned optical fiber equalization adjuster integrally formed on the same substrate;
An array fiber in which a plurality of optical fibers are taped, wherein each of the optical fiber equalization adjusters is connected to the optical fiber in a one-to-one relationship. Further, a fiber amplifier array doped with rare earth ions can be used as the array fiber. In this case, excitation light of the fiber amplifier array is introduced from the light source to the fiber amplifier array. The directional coupler type confluence may be formed integrally with the isometric adjuster.

A sixteenth aspect of the present invention is an array type optical fiber equalizing length adjuster comprising an array fiber amplifier comprising a plurality of optical fibers containing rare earth ions and a delay adjusting device connected to one end of the array fiber amplifier. The delay adjustment device includes an optical waveguide substrate, at least one excitation light source, a tape fiber including a plurality of cores, and a plurality of tape fibers formed on the optical waveguide substrate and connecting the array fiber amplifier and the tape fiber. An optical signal waveguide, a plurality of excitation light waveguides formed on the optical waveguide substrate and connected to the optical signal waveguide, an optical fiber connecting the excitation light source and the excitation light waveguide, and formed on the optical waveguide substrate; Provided is an array-type optical fiber equalizing length adjuster, which comprises a directional coupler for coupling an optical signal waveguide and a pumping optical waveguide, respectively.

Also, as described in claim 17, the delay adjusting device can be connected to both ends of the array fiber amplifier. As described in claim 18, the excitation light source may be formed on the optical waveguide substrate, and the excitation light source may be directly connected to the excitation light waveguide. Also, as described in claim 19,
A grating reflector can be used as the directional coupler.

According to a twentieth aspect of the present invention, an array-type optical fiber equalization adjuster includes a light guide for connecting any one of the above-described optical fiber equalization adjusters to each of the optical signal waveguides. It can be configured by forming it on a waveguide substrate. Claim 21 is an array fiber amplifier comprising a plurality of optical fibers containing rare earth ions, a delay adjusting device connected to one end of the array fiber amplifier, and any one of the above-mentioned devices connected to the other end of the array fiber amplifier. An optical fiber isometric adjuster, comprising: an array-type optical fiber isometric adjuster, comprising: an optical waveguide substrate, at least one excitation light source, and a tape fiber including a plurality of cores. A plurality of optical signal waveguides formed on the optical waveguide substrate and connecting the array fiber amplifier and the tape fiber; and a plurality of excitation light waveguides formed on the optical waveguide substrate and connected to the optical signal waveguide, An optical fiber connecting the pumping light source and the pumping optical waveguide, and a directional coupler formed on the optical waveguide substrate and coupling the optical signal waveguide and the pumping optical waveguide, respectively. Providing an array type optical fiber length-equalization regulator that.

In the present invention, one of the delay waveguides having an optimum delay time is selected from a plurality of delay waveguides having different optical path lengths, and the input waveguide is selected via the delay waveguide. Provided is an optical fiber equalization adjusting method for transmitting an optical signal from a waveguide to an output waveguide. According to a twenty-third aspect, a delay waveguide through which an optical signal passes can be changed according to a change in the refractive index of the delay waveguide.

[0038]

According to the present invention, by selecting a delay waveguide having an optimum delay amount from among delay waveguides having different delay amounts inside the equal length module, a fiber error generated at the time of manufacturing a fiber connector can be reduced. It becomes possible to adjust the total length of the fiber patch cord so that the absorption and the delay time in the transmission of the optical signal become constant.

Further, according to the present invention, it is possible to prevent a decrease in yield due to a fiber length error due to failure in polishing of an end face of a patch cord at the time of manufacturing a fiber connector.
Further, in the conventional delay adjuster, the fiber amplifier doped with rare earth ions is composed of individual components such as couplers, so that it is very difficult to control the transmission delay time. It is possible to control the overall length of the fiber amplifier to which similar ions are added with high accuracy.

[0040]

BEST MODE FOR CARRYING OUT THE INVENTION

[0041]

FIG. 1 shows a delay adjuster 00 according to a first embodiment of the present invention. The optical fiber equalization adjuster 00 shown in FIG. 1 includes a waveguide substrate 01 and an optical waveguide circuit formed on the waveguide substrate 01. The waveguide substrate 01 is connected to the input optical fiber 02 and the output optical fiber 03, respectively.

The optical waveguide circuit includes a delay waveguide group 06 composed of a plurality of delay waveguides 061 to 06n having different optical path lengths, an input waveguide 02a connected to the input optical fiber 02, and an output light. An output side waveguide 03a connected to the fiber 03, an input side branch portion 04 as an input side connection portion connecting the delay waveguide group 06 and the input side waveguide 02a, a delay waveguide group 06 and the output side Waveguide 03a
Merging section 05 as an output side connecting section for connecting
And consisting of

The input-side branch section 04 has a function as an optical switch, and guides input light incident from the input-side optical fiber 02 to one of the plurality of delay waveguides 061 to 06n. The output-side merging unit 05 has a function as an optical switch similarly to the input-side branching unit 04, and guides the optical signal from the delay waveguide group 06 to the output-side optical fiber 03.

The optical fiber equalizing length adjuster according to the present embodiment having the above-described configuration operates as follows. A connector or another optical module is connected to each end of the input optical fiber 02 and the output optical fiber 03, and the total length of the optical fiber cable is defined as the length between the end points. The total length of this optical fiber cable is
Due to the assembly error when connecting to these optical connectors or other optical modules, an error occurs with respect to the desired length accuracy. For this error, the delay waveguide 0 through which the optical signal passes
By setting 6 to the optimum delay time, it is possible to absorb an error in the desired length accuracy.

More specifically, the initial length at the time of manufacturing the optical fiber cable is set within a range that can be adjusted by the delay waveguide, and assembly with the connector or the optical module is performed. After that, the input side branching unit 04 and the output side merging unit 05 functioning as an optical switch are controlled, and one delay waveguide having an optimum delay amount is selected from the delay waveguide group 06. As a result, it is possible to absorb the error of the fiber cable length generated at the time of assembling with the connector or the optical module, and to precisely adjust the entire length of each fiber cable.

[0046]

[Example of First Embodiment] The configuration of an example of the first embodiment will be described with reference to FIG. The bit rate of the optical signal passing through the inside of the input side branching unit 04 and the output side merging unit 05 is set to 10 Gbps. It is assumed that a plurality of optical cell (or packet) signals transmitted in the same clock with the same phase arrive at the same receiver after passing through different paths. When the receiver uses the same clock for reception, the skew between optical cells allowed to suppress the increase in the amount of deterioration in reception sensitivity is about 1/10 of 1 bit. The time of the allowable skew corresponds to 10 psec, which is 2 mm when converted into the length of the optical fiber.
That is, the error of the optical fiber length is about 2 mm (± 1 mm)
It is required that: For this reason, the optical path length differences of the respective delay waveguides 061 to 06n are manufactured in 2 mm steps.

The delay waveguide 0 constituting the delay waveguide group 06
The number n of 61-06n is determined by the error in the length of the optical fiber to be absorbed. For example, in the assembly of the optical connector, if an error of ± 2 mm at one end is allowed, the error at both ends of the fiber cable is ± 4 mm at the maximum. Therefore, four delay waveguides 061 to 064 are required (± 4 mm ÷ ± 1 mm = 4).

Here, as the waveguide substrate 01, a silica-based quartz glass substrate, an organic substrate, a LiNbO ₃ substrate,
A substrate made of any optical waveguide material, such as a compound semiconductor substrate, can be used. Further, the waveguide substrate 01
Each of the delay waveguides 061-0 of the delay waveguide group 06 formed in
6n can be provided as a difference in path length or a difference in refractive index.

Next, the configuration of the input-side branching unit 04 functioning as an optical switch will be described. The input-side branching unit 04 and the output-side merging unit 05 are both composed of 1 × n optical switches composed of waveguides. In such a configuration, assuming that the optical fiber is assembled to the optical connector, further adjusted, and it is assumed that adjustment after actually mounting it inside the delay adjuster is unnecessary, it is used for the input-side branching unit 04 and the output-side merging unit 05. As the 1 × n optical switch as the route selecting means, a fixed one that does not require control after mounting is appropriate.
For that purpose, it is necessary to fix the connection state of the 1 × n optical switch.

As a typical example of such a 1 × n optical switch, as shown in FIG. 2, there are a plurality of 1 × 2 optical switches connected in multiple stages. In the multi-stage connection optical switch shown in FIG. 2, the input side optical fiber 041 is the first 1 × 2 optical switch 042.
a 1 × 2 optical switch 042a
Is further connected to a pair of second 1 × 2 optical switches 042b. Two delay waveguides are connected to each of the pair of second 1 × 2 optical switches 042b.

As a means for fixing the connection state of the 1 × n optical switch, a distortion is generated in the delay waveguide and its vicinity by heating, or an impurity is added to the delay waveguide, thereby constantly changing the refractive index. There is a way to keep the changes. The means for generating distortion by heating includes irradiating the waveguide substrate 01 with high-power laser light, or using a heater formed near the delay waveguide 061-06n on the waveguide substrate 01.

FIG. 3 shows an example of an optical patch cord using the optical fiber equalization adjuster 00 according to the first embodiment shown in FIG. The optical patch cord shown in FIG. 3 includes the optical fiber equalization adjuster 00 shown in FIG. 1, an input optical fiber 02 and an output optical fiber 03 connected to the optical fiber equalization adjuster 00, The electrodes 21 and 0 connected to the input side optical fiber 02 and the output side optical fiber 03, respectively.
31.

In such an optical patch cord, when the input side optical fiber 02 and the output side optical fiber 03 are connected to the delay adjuster 00, and the waveguide substrate 01 is sealed to form a module structure, the electrodes 021, The waveguide substrate 01 can be heated by leading the power supply 031 to the outside of the module and connecting a power supply to the electrodes 21 and 031. For this reason, since the manufacture of the entire optical patch cord including the sealing of the waveguide substrate 01 and the adjustment of the entire length of the optical patch cord can be performed in separate steps, a method of heating the waveguide substrate 01 using a heater is used. Is advantageous for cost reduction.

A procedure for adjusting the total length of the fiber in the optical patch cord shown in FIG. 3 will be described with reference to FIG. FIG. 4 shows an example of a delay adjuster for selecting a delay waveguide having an optimal amount of delay from the delay waveguide group 06 of the optical fiber equalization adjuster 00. The delay adjuster is connected to the optical fiber equalization adjuster 00, the input optical fiber 02 and the output optical fiber 03 connected to the optical fiber equalization adjuster 00, and connected to the input optical fiber 02. A short pulse generator 21 and a waveform observation device 22 connected to the output side optical fiber 03.

This delay adjuster operates as follows.
The optical short pulse 24 output from the short pulse generator 21 enters the input side optical fiber 02, passes through the optical fiber equalization adjuster 00, and is output from the output side optical fiber 03 to the pulse train 25.
Is output as This pulse train 25 is applied to the waveform observation device 22.
Observed by

A synchronizing signal 23 is emitted from the short pulse generator 21 to the waveform observer 22. Multiple pulse trains 25
Are compared with each other on the basis of the synchronization signal 23, and an optimum delay waveguide is selected from the delay waveguide group 06 by this comparison. For example, when the optical path length difference in each of the delay waveguides 061-06n of the delay waveguide group 06 is a step of 2 mm, the time difference corresponds to 10 psec as described above. Therefore, when an optical pulse having a pulse width of 10 psec or less is input from the input optical fiber 02, the delay waveguide 061-06n is output from the output optical fiber 03.
N consecutive optical pulse trains equal to the number of
Obtained at intervals. When an optical pulse having a delay time closest to the required delay time of the optical patch cord is selected from the optical pulse train, one delay waveguide corresponding to the optical pulse can be specified.

Thereafter, the input-side branch portion 04 and the output-side junction portion 05 as optical switches are fixed to a desired delay path by irradiating a high-power laser beam such as a YAG laser or heating by a heater. In addition, when a heater is used to control the input-side branch unit 04 and the output-side junction unit 05 as an optical switch, the input-side branch unit 04 and the output-side junction unit can be used without using the optical short pulse 24. 05 can be adjusted.

For example, by using a continuous optical signal modulated at 10 Gbps NRZ and observing its waveform, it is possible to observe a difference in delay time of 10 psec. By continuously and weakly heating the heater formed on the waveguide substrate 01, each of the delay waveguides 061-0 is heated.
6n causes a reversible refractive index change, so that the input-side branch unit 04 and the output-side junction unit 05 as optical switches can be temporarily switched.

Therefore, a continuous optical signal of 10 Gbps is incident on the optical patch cord, and the path of the delay waveguide that optimizes the delay time of the transmitted optical signal obtained at the output-side merging section 05 is changed to an optical switch (input side branch). Unit 04 and output side merging unit 05)
Select by switching. After that, by increasing the amount of heating by the heater, an irreversible change in the refractive index is generated, and the optical switch is fixed so as to have an optimal path. By using such a method, adjustment after mounting the fiber in the delay adjuster is also possible.

By applying such a 1 × n optical switch to the input-side branching unit 04 and the output-side merging unit 05, the total power of the input optical signal is output via only one delay waveguide. Therefore, the power of the optical signal is lossless in principle. FIG. 5 shows an example of a delay adjuster for selecting a delay waveguide by using the optical fiber equalization adjuster 00 shown in FIG. 1 and the above-described reversible optical switch.

As shown in FIG. 5, the optical fiber equalization adjuster 00 is an optical transmitter 211 mounted in the same delay adjuster.
And an optical receiver 221 in the optical fiber path. That is, the optical fiber equalization adjuster 0
0 is connected to the optical transmitter 211 via the input side optical fiber 02, and is connected to the optical receiver 221 via the output side optical fiber 03.
Is connected to An optical switch capable of reversible switching is used as the 1 × n optical switch constituting the force-side branching unit 04 and the output-side merging unit 05 of the optical fiber equalization adjuster 00. These 1 × n optical switches are controlled by an optical switch control circuit 26.

The input optical signal emitted from the signal generator 21 is output as an output signal 224 from the optical receiver 221 via the optical transmitter 211 and the optical fiber equalization adjuster 00. The bit phase extraction circuit 222 extracts the bit phase of the input optical signal from the output signal 224 and transmits a signal representing this phase to the delay difference detection circuit 223. Delay difference detection circuit 2
Reference numeral 23 compares this signal with a reference signal 23 issued from the signal generation circuit 21 to detect a change in a bit phase difference, that is, a delay difference. The fluctuation amount of the delay difference detected by the delay difference detection circuit 223 is transmitted to the optical switch control circuit 26, and the delay amount of the optical fiber equalization adjuster 00 is controlled to an optimum value. For example, when the delay difference detected by the delay difference detection circuit 223 exceeds an allowable value, the optical switch control circuit 26 switches the optical switch of the optical fiber equalization adjuster 00. This compensates for variations in fiber length.

In order to absorb a decrease in the yield due to an abnormal polishing of the end face at the time of assembling the connector, it is necessary to absorb a cutting amount of the fiber which is cut when the assembling of the connector fails. For example, taking the case of the SC connector as an example, the length of the fiber cut at the time of reassembly is approximately 15 mm. 2 mm described in the above embodiment
In order to absorb such a large error by using the structure of the delay adjustment waveguide of the step (± 1 mm), 12 delay waveguides are required in addition to the four delay waveguides necessary for absorbing the assembly error. Required.

Although an optical switch formed on a waveguide substrate has no loss in principle, an excess loss occurs in each 1 × 2 optical switch unit. Accordingly, there is a problem that the loss increases. For this increase in loss, an optical fiber equalization adjuster 00 as shown in FIG. 6 can be used. The delay waveguide group 06a in the optical fiber equalization adjuster 00 shown in FIG. 6 is composed of a combination of a coarse adjustment delay waveguide group 06C and a fine adjustment delay waveguide group 06F. That is, by forming a two-stage delay waveguide group, it is possible to avoid an increase in loss. Coarse adjustment side delay waveguide group 0
6C compensates for the delay for a fiber length of about 15 mm to cut during reassembly of the connector. The fine adjustment side delay waveguide group 06F absorbs a connector assembly error. The fine adjustment-side delay waveguide group 06F is composed of a plurality of delay waveguides of 2 mm steps similar to the delay waveguide group 06 in the optical fiber equalization adjuster 00 shown in FIG.

FIG. 7 shows another embodiment of the optical fiber equalization adjuster 00. In the optical fiber equalization adjuster 00, a fiber amplifier 12 doped with rare earth ions is used as an input side optical fiber. The fiber amplifier 12 doped with rare earth ions is the output side optical fiber 03
It is also possible to use as. For example, when the input side optical fiber is composed of the rare earth ion-doped fiber amplifier 12, it is necessary to use an excitation light source to excite the rare earth ion-doped fiber amplifier 12. However, there is a problem that an equal length error occurs when the pump light emitted from the pump light source and the optical signal transmitted through the input waveguide 02a (see FIG. 1) are combined.

FIG. 8 shows an example of a delay adjuster for avoiding this error. As shown in FIG. 8, the delay waveguide group 0
Numeral 6 is connected to a rare earth ion-doped fiber amplifier 12 as an input optical fiber via an input waveguide 16. The excitation light emitted from the excitation light source 11 is the optical fiber 1
1a, and enters the waveguide 13. The waveguide 13 is
It merges with the input-side waveguide 16 via a merger 14 formed on the waveguide substrate. Therefore, the waveguide 13
The excitation light transmitted through the
6 converges with an optical signal passing through the optical signal.

With the delay adjuster having such a configuration, the above-described problem of the error of equal length can be avoided. FIG. 9 shows an example of an optical switch used in the input side branching unit 04 and the output side merging unit 05. The optical signal input from the input side waveguide 041 is branched by the input side branching unit 043 to each of the delay waveguides 061-06n. Each delay waveguide 0
A transmission amount adjustment area 071-07n for adjusting the transmission amount of the optical signal is provided on the path 61-06n. By adjusting these transmission amount adjustment regions 071-07n, only one delay waveguide is set in a transmission state.

By using an optical switch having such a configuration for at least one of the input-side branch unit 04 and the output-side junction unit 05, it is also possible to configure an optical fiber equalization adjuster. Transmission amount adjustment area 071-
As described in the above embodiment, the adjustment of the transmission amount of the optical signal at 07n can be performed by using the high-power laser beam irradiation or the thermal refractive index change by the heater. Further, each delay waveguide 061-06n is disclosed in
The semiconductor optical amplifier may be configured as a waveguide type optical fiber amplifier by adding rare earth ions proposed in Japanese Patent Application Laid-Open No. 1115, or by using a method proposed in Japanese Patent Application Laid-Open No. 1-253718. Wave path 061-0
6n, it is also possible to control the transmission amount of the optical signal in the transmission amount adjustment region 071-07n by injecting or blocking the excitation light or the current.

FIG. 10 shows an example of a delay adjuster in which the optical fiber equalization adjuster 00 shown in FIG. 1 is applied to an array fiber. The delay adjuster shown in FIG.
1, a plurality of optical fiber equalization adjusters 00 shown in FIG. 1 formed on a waveguide substrate 01, and an array fiber 02T obtained by tapering a plurality of optical fibers 021-02n.
And consisting of Each of the optical fiber equalization adjusters 00 is connected to the optical fiber 021-02n in a one-to-one relationship.

That is, the present delay adjuster is connected to the optical fiber 0
21-02n and the optical fiber equalization adjuster 00 are both arrayed, and the arrayed optical fiber equalization adjuster 00 is connected to the array fiber 02T in which the optical fibers are arrayed. The configuration of the delay adjuster is applicable to all optical fiber equalization adjusters according to the embodiments described above.

[0071]

Second Embodiment FIG. 11 shows an optical fiber equalization adjuster according to a second embodiment of the present invention. The optical fiber equalization adjuster according to the present embodiment constitutes an array type optical fiber equalization adjuster. An array-type optical fiber equalization controller according to the present embodiment is an array fiber amplifier 1 including a plurality of optical fibers 121 to 12n containing rare earth ions.
2T, and a delay adjusting device connected to one end of the array fiber amplifier 12T.

The other end of the array fiber amplifier 12T is formed on a connector 181. The delay adjusting device includes an optical waveguide substrate 10, a plurality of excitation light sources 11, and a plurality of cores 1.
63, one end of which is formed on the connector 182, and the array fiber amplifier 12 which is formed on the optical waveguide substrate 10 and is arrayed together.
A plurality of input-side optical signal waveguides 161 and output-side optical signal waveguides 162 connecting the T and the tape fiber 163T;
A plurality of excitation optical waveguides 1 formed on an optical waveguide substrate 10
3, connecting the excitation light source 11 and the excitation light waveguide 13;
Array fiber amplifier 1 including a plurality of optical fibers 12
2U, and a directional coupler 14 formed on the optical waveguide substrate 10 and coupling the input optical signal waveguide 161, the output optical signal waveguide 162, and the pumping optical waveguide 13.

The optical signal is transmitted to the rare earth ion-doped fiber 12.
The light enters from T, passes through the input-side optical signal waveguide 161 and the output-side optical signal waveguide 162, and is output from the tape fiber 163T. In the present array-type optical fiber equalization adjuster, optical signals can be transmitted in both directions in principle, and there is no input / output directionality. The excitation light for exciting the rare earth ion-doped fiber 12T is the excitation light source 11
The light exits through the excitation light waveguide 13, joins the optical signal waveguide 161 from the directional coupler 14 as the excitation light junction, and enters the rare-earth ion-doped fiber 12 </ b> T.

Next, an embodiment of the array-type optical fiber equalization adjuster shown in FIG. 11 will be described below. A plurality of input-side optical signal waveguides 1 are provided on an optical waveguide substrate 10 at intervals of 250 μm.
61 and an output-side optical signal waveguide 162, a plurality of erbium-doped fibers (hereinafter referred to as “tape EDF”) 12T taped at 250 μm intervals at one end of the input-side optical signal waveguide 161, and an output. Side optical signal waveguide 16
A plurality of normal tape fibers 163T also taped at intervals of 250 μm were respectively connected to the opposite ends of the two. The optical fibers connected to both ends of the input-side optical signal waveguide 161 and the output-side optical signal waveguide 162 are cut to a prescribed length, and the ends of the optical fibers are connected to the multi-core connectors 181 and 182 or the single-core connectors, respectively. Processed as a connector.

The input side and output side optical signal waveguides 161 and 162 on the optical waveguide substrate 10 are respectively coupled with directional couplers 14 having wavelength dependency. The optical fiber 12 connected to the excitation light waveguide 13 and the excitation light source 11 are connected. The directional coupler 14 transmits a 1.55 μm optical signal from the input side optical signal waveguide 161 to the output side optical signal waveguide 162, or
Pass in the opposite direction. The excitation light output from the excitation light source 11 enters the directional coupler 14 via the excitation light waveguide 13 and is emitted to the input side optical signal waveguide 161.

FIG. 12 shows a second example of the optical fiber equalization adjuster according to the second embodiment. In the optical fiber equalizing length adjuster shown in FIG. 11, a multi-core connector 181 is formed at one end of the tape EDF12T, and a delay adjusting device is connected at the other end. In the second example shown in FIG. , Delay adjusting devices are symmetrically connected to both ends of the tape EDF12T. The configuration of the delay adjustment device in this example is the same as the configuration of the delay adjustment device shown in FIG. However, the optical fibers 12 connecting the excitation light source 11 and the excitation light waveguide 13 are not arrayed.

FIG. 13 shows a first modification of the array-type optical fiber equalization adjuster shown in FIG. The pumping light source 11 in this modified example is mounted on the optical waveguide substrate 10 and is directly used as the pumping light waveguide 13 unlike the pumping light source 11 in the array type optical fiber equalization length adjuster shown in FIG. Therefore, in this modification, the excitation light source 1
Optical fiber 12 connecting optical fiber 1 and pumping optical waveguide 13
Need not be provided.

FIG. 14 shows a second modification of the array-type optical fiber equalization adjuster shown in FIG. In this modification, the excitation light source 11 is mounted on the optical waveguide substrate 10 and the excitation light source 11
Directional coupler 14 that joins the excitation light from the light source with the incident light
Is a reflection type using a grating reflector 14G formed on the waveguide substrate 10. By using the grating reflector 14G, the directional coupler 1
The length of the waveguide at the portion 4 can be reduced by half, and the optical waveguide substrate 10 can be reduced in size.

FIG. 15 shows a third modification of the array-type optical fiber equalization adjuster shown in FIG. In the array-type optical fiber equalization adjuster according to the present modification, for example, the optical fiber equalization adjuster 00 shown in FIG. 1 is formed on each delay waveguide. Other configurations are shown in FIG.
This is the same as the array-type optical fiber equalization adjuster according to the second modification shown in FIG.

FIG. 16 shows a fourth modification of the array type optical fiber equalization adjuster shown in FIG. In the fourth modification shown in FIG. 16, a delay adjusting device similar to the delay adjusting device shown in FIG. 13 is connected to one end of the tape EDF 12T, and a waveguide substrate is connected to the other end of the tape EDF 12T. A plurality of optical fiber equalization adjusters 00 formed on the optical fiber 01 are connected.

[0081]

As described above, the present invention has the following effects. A first effect is that the cost of parts required for skew suppression can be reduced in a transmission path of an optical cell (or packet) switch using an optical signal of a class exceeding several Gbps.

The reason is that the combination of an optical waveguide element having a simple structure and capable of trimming the path length enables
This is because it is possible to significantly suppress a decrease in yield due to inaccuracy in length at the time of assembling a fiber cable with a connector whose entire length is specified with an accuracy of about 1 mm. The second effect is that a delay adjuster required for skew suppression can be miniaturized in a transmission path of an optical cell (or packet) switch using an optical signal of a class exceeding several Gbps.

The reason for this is that the mechanical variable fine adjustment mechanism is eliminated, and the path length is adjusted by trimming, and an optical waveguide element that fixes the path length during manufacturing is used. A third effect is that the cost of adjusting the fiber length of an optical fiber cable or an optical module with an optical fiber can be reduced. The reason for this is that individual adjustments can be made for each optical component, and requirements for wavelength, light intensity, signal format, etc. for the characteristics of the adjustment optical signal are greatly relaxed compared to adjustments made after the entire optical path is assembled. That is because

The fourth effect is that the total length of the arrayed fiber amplifier can be controlled. Conventionally, it was difficult to control the fiber length in units of 1 mm because it is composed of a plurality of optical components. However, according to the present invention, even for an arrayed fiber amplifier doped with rare earth ions,
For the purpose of equal length, the total length of the arrayed fiber amplifier can be controlled.

The reason for this is that, in the past, individual fiber couplers were connected to each fiber amplifier in order to combine pumping light. However, in the present invention, an array of directional lights is arranged on a delay waveguide. This is for forming the excitation light converging portion using the coupler.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an optical fiber equalization adjuster according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a configuration of an input-side branch unit as an optical switch.

FIG. 3 is a plan view showing an overall configuration of an optical patch cord to which the optical fiber equalization adjuster according to the first embodiment of the present invention is applied.

FIG. 4 is a block diagram of an example of a device that performs delay adjustment using the optical fiber equalization adjuster shown in FIG. 1;

FIG. 5 is a block diagram of another example of a device for performing delay adjustment using the optical fiber equalization adjuster shown in FIG. 1;

FIG. 6 is a schematic diagram showing a configuration of a modification of the optical fiber equalization adjuster according to the first embodiment of the present invention.

FIG. 7 is a schematic diagram illustrating a configuration of a modification of the optical fiber equalization adjuster according to the first embodiment of the present invention.

FIG. 8 is a schematic diagram showing a configuration of a modification of the optical fiber equalization adjuster according to the first embodiment of the present invention.

FIG. 9 is a schematic diagram illustrating an example of a configuration of an input-side branch unit included in the optical switch.

FIG. 10 is a schematic diagram showing a configuration of an application example of the optical fiber equalization adjuster according to the first embodiment of the present invention.

FIG. 11 is a schematic diagram illustrating an optical fiber equalization adjuster according to a second embodiment of the present invention.

FIG. 12 is a schematic diagram showing a configuration of a modification of the optical fiber equalization adjuster according to the second embodiment of the present invention.

FIG. 13 is a schematic diagram showing a configuration of a modification of the optical fiber equalization adjuster according to the second embodiment of the present invention.

FIG. 14 is a schematic diagram illustrating a configuration of a modification of the optical fiber equalization adjuster according to the second embodiment of the present invention.

FIG. 15 is a schematic diagram showing a configuration of a modification of the optical fiber equalization adjuster according to the second embodiment of the present invention.

FIG. 16 is a schematic diagram showing a configuration of a modification of the optical fiber equalization adjuster according to the second embodiment of the present invention.

FIG. 17 is a schematic diagram showing a configuration of a conventional optical fiber equalization adjuster.

FIG. 18 is a block diagram illustrating an example of an optical fiber equalization adjuster.

[Explanation of symbols]

 00 Optical fiber equalization adjuster 01 Waveguide substrate 02 Input side optical fiber 02a Input side waveguide 02T Array fiber 03 Output side optical fiber 03a Output side waveguide 04 Input side branch part 05 Output side merging part 06 Delay waveguide group 061-06n delay waveguide 06C coarse adjustment delay waveguide group 06F fine adjustment delay waveguide group 07 transmission amount adjustment region 10 optical waveguide substrate 11 excitation light source 12 rare earth ion-doped fiber amplifier 12T array fiber amplifier 13 excitation light waveguide 14 Directional coupler 14G Grating reflector 21 Short pulse light source 22 Waveform observer 23 Synchronous signal 24 Optical short pulse 25 Optical short pulse train 26 Optical switch control circuit 161 Input side optical signal waveguide 162 Output side optical signal waveguide 163T Tape fiber 181 Array connector 182 Array connector Data 211 optical transmitter 221 optical receiver 222 bit phase extraction circuit 223 delay difference detecting circuit

──────────────────────────────────────────────────の Continuation of the front page (51) Int.Cl. ⁶ Identification code FI H04B 10/12 (72) Inventor Akio Tajima 5-7-1 Shiba, Minato-ku, Tokyo NEC Corporation (72) Invention Person Yoshiharu Maeno 5-7-1 Shiba, Minato-ku, Tokyo Inside the NEC Corporation (72) Inventor Naoya Hemi 7-1-1 Shiba, Minato-ku, Tokyo Inside NEC Corporation

Claims (23)

[Claims] 1. An optical fiber equalization adjuster comprising a waveguide substrate and an optical waveguide circuit formed on the waveguide substrate, wherein the optical waveguide circuit has a plurality of optical path lengths different from each other. A delay waveguide group including a delay waveguide, an input-side connection unit that connects the delay waveguide group to an input-side optical fiber, and an output-side connection unit that connects the delay waveguide group to an output-side optical fiber. An optical fiber equalization adjuster characterized by comprising: 2. The optical fiber according to claim 1, wherein the difference in optical path length between the delay waveguides is caused by a difference in a path length of the delay waveguide or a difference in a refractive index. Moderator. 3. The optical fiber equalization according to claim 1, wherein the number of the waveguides constituting the delay waveguide group is a function of an error of an optical fiber length to be absorbed. Moderator. 4. The apparatus according to claim 1, further comprising a heater formed on said waveguide substrate for heating said delay waveguide and reversibly changing a refractive index.
The optical fiber equalization adjuster according to any one of claims 1 to 4. 5. A transmission amount adjusting region for adjusting a transmission amount of an optical signal is formed in each of the delay waveguides constituting the delay waveguide group, and the input side connection portion adjusts the transmission amount. The optical fiber equalization adjuster according to any one of claims 1 to 4, wherein an area is adjusted so that an optical signal can pass through only one delay waveguide. 6. At least one of the input-side waveguide and the output-side waveguide comprises a waveguide doped with rare-earth ions, and the optical fiber equalization adjuster includes the input-side waveguide or the input-side waveguide. An excitation light source that emits excitation light that excites an output-side waveguide, and a junction that merges the excitation light with the input-side waveguide or the output-side waveguide, further includes a junction on the waveguide substrate. The optical fiber equalizing length adjuster according to any one of claims 1 to 5, wherein the optical fiber length adjuster is formed. 7. A means for selecting a signal light path in at least one of the input side connection part and the output side connection part or at least one of the delay waveguides, The path selection means selects one delay waveguide having an optimum delay time from the delay waveguide group, and transmits the signal light from the input waveguide to the output waveguide via the delay waveguide. The optical fiber equalization length adjuster according to claim 1, wherein the optical fiber equalization adjuster adjusts the transmission delay time of the signal light. 8. An optical switch capable of changing a path passing through the delay waveguide according to at least one of a refractive index of the waveguide and at least one of the input-side connection and the output-side connection. The optical fiber equalizing length adjuster according to any one of claims 1 to 6, wherein: 9. At least one of the input-side connection portion and the output-side connection portion is a plurality of the connection portions already established between the input side waveguide or the output side waveguide and the delay waveguide group. 7. The optical fiber equalization adjustment according to claim 1, comprising an optical switch for selecting, by trimming, a single path having an optimum delay amount from among the connections described above. vessel. 10. The at least one of the input side connection part and the output side connection part selects only one connection having an optimum delay amount from the delay waveguide group, and selects the input side waveguide or the output side. 7. The optical fiber equalizing length adjuster according to claim 1, comprising an optical switch that forms a waveguide by trimming a side waveguide. 11. At least one of the input-side connection and the output-side connection comprises an optical switch of a type in which the state is constantly maintained after changing the path of an optical signal. The optical fiber equalizing length adjuster according to claim 8, wherein: 12. The apparatus according to claim 1, wherein at least one of the input side connection part and the output side connection part is formed by connecting 1 × n optical switches in multiple stages. The optical fiber equalization adjuster according to item. 13. The delay waveguide group according to claim 1, wherein a coarse adjustment delay waveguide and a fine adjustment delay waveguide having different unit delay times are combined in series.
13. The optical fiber equalization adjuster according to any one of claims 12 to 12. 14. An optical fiber equalization adjuster according to claim 1, which is integrated and formed on the same substrate, an array fiber in which a plurality of optical fibers are taped, and An array-type optical fiber equalization adjuster, wherein each of the optical fiber equalization adjusters is connected to the optical fiber in a one-to-one relationship. 15. The array fiber is a fiber amplifier array to which rare earth ions are added, and the directional coupler-type converging section for introducing excitation light of the fiber amplifier array from a light source to the fiber amplifier array is adjusted to be equal in length. 15. The array-type optical fiber equalization adjuster according to claim 14, wherein the fiber amplifier array is made equal in length by being integrally formed with a device. 16. An array fiber amplifier comprising a plurality of optical fibers containing rare earth ions, and a delay adjusting device connected to one end of the array fiber amplifier, wherein the delay adjusting device comprises: an optical waveguide substrate; One excitation light source, a tape fiber composed of a plurality of cores, a plurality of optical signal waveguides formed on the optical waveguide substrate, and connecting the array fiber amplifier and the tape fiber, and on the optical waveguide substrate A plurality of excitation light waveguides connected to the optical signal waveguide, an optical fiber connecting the excitation light source and the excitation light waveguide, and formed on the optical waveguide substrate, the optical signal waveguide; A directional coupler that couples the pumping light waveguides with each other; and an array-type optical fiber equalization adjuster, comprising: 17. An array fiber amplifier comprising a plurality of optical fibers containing rare earth ions, and a delay adjusting device connected to both ends of the array fiber amplifier, wherein the delay adjusting device comprises: an optical waveguide substrate; One excitation light source, a tape fiber composed of a plurality of cores, a plurality of optical signal waveguides formed on the optical waveguide substrate, and connecting the array fiber amplifier and the tape fiber, and on the optical waveguide substrate A plurality of excitation light waveguides connected to the optical signal waveguide, an optical fiber connecting the excitation light source and the excitation light waveguide, and formed on the optical waveguide substrate, the optical signal waveguide; A directional coupler that couples the pumping light waveguides with each other; and an array-type optical fiber equalization adjuster, comprising: 18. The array type optical fiber according to claim 16, wherein said excitation light source is formed on said optical waveguide substrate, and said excitation light source is directly connected to said excitation light waveguide. Lengthening regulator. 19. The array-type optical fiber equalizing length adjuster according to claim 16, wherein the directional coupler forms a grating reflector. 20. The optical fiber equalization adjuster according to claim 1, formed on the optical waveguide substrate so as to be connected to each of the optical signal waveguides. The array-type optical fiber equalization adjuster according to any one of claims 14 to 19. 21. An array fiber amplifier comprising a plurality of optical fibers containing rare earth ions, a delay adjusting device connected to one end of the array fiber amplifier, and connected to the other end of the array fiber amplifier. An optical fiber equalization adjuster according to any one of claims 1 to 7, wherein the delay adjuster includes: an optical waveguide substrate; at least one excitation light source; and a tape fiber including a plurality of cores; A plurality of optical signal waveguides formed on the optical waveguide substrate and connecting the array fiber amplifier and the tape fiber; and a plurality of excitation light guides formed on the optical waveguide substrate and connected to the optical signal waveguide. A waveguide, an optical fiber connecting the pumping light source and the pumping optical waveguide, and an optical signal waveguide and the pumping optical waveguide formed on the optical waveguide substrate. Array optical fiber length-equalization regulator is made of a directional coupler which, respectively binding,. 22. One delay waveguide having an optimum delay time is selected from a plurality of delay waveguides having different optical path lengths, and light is transmitted from the input waveguide to the output waveguide via the delay waveguide. An optical fiber equalization adjustment method for transmitting a signal. 23. The method according to claim 22, wherein a delay waveguide through which the optical signal passes is changed according to a change in the refractive index of the delay waveguide.