JP3358947B2 - Optical multiplexer / demultiplexer and optical transmission system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for optical wavelength division multiplexing communication. In particular, the present invention relates to an optical multiplexing / demultiplexing device that multiplexes and demultiplexes optical signals multiplexed at different wavelengths in an optical transmission line.

[0002]

2. Description of the Related Art Conventionally, as an example of an optical multiplexing / demultiplexing apparatus, there has been one disclosed in, for example, Japanese Patent Application Laid-Open No. 05-102929. FIG. 21 is an explanatory diagram of a conventionally proposed optical multiplexer / demultiplexer. In FIG. 21, reference numerals 11 and 13 are input terminals for inputting optical signals. 14 and 15 are output terminals,
243 is an output line, and 241 and 242 are optical filters. The optical filter 241 has a function of inputting the wavelength-multiplexed optical signal from the terminal 11 and demultiplexing the optical signal into a first wavelength group and a second wavelength group. The first wavelength group is output from the output terminal 14. The optical filter 242 is demultiplexed by the optical filter 241, and the optical signal of the second wavelength group input through the output line 243 and the light of the same wavelength as the first wavelength group input from the input terminal 13 and input from the input terminal 13. The signals are multiplexed and output from the output terminal 15.

FIG. 22 shows transmission characteristics when a Mach-Zenda type filter is used as the optical filters 241 and 242. Its transmission characteristics are sinusoidal with respect to wavelength,
The optical filter 241 has two optical waveguides in the internal optical circuit, and by adjusting the optical path length difference, a wavelength group including the wavelength λ1 is coupled between the input terminal 11 and the output terminal 14 so that the input The wavelength group including the wavelength λ2 is set to be coupled between the terminal 11 and the output line 243. That is, the optical filter 241 separates the light of the wavelength group including the wavelength λ1 and the light of the wavelength group including the wavelength λ2. In the optical filter 242, the light of the wavelength group including the wavelength λ1 and the light of the wavelength group including the wavelength λ2 are multiplexed by reversing the traveling direction of the light.

The operation will be described. The wavelength multiplexed light obtained by multiplexing the wavelengths λ1 and λ2 input from the input terminal 11 is input to the optical filter 241. In the optical filter 241, the wavelength λ1 is output from the output terminal 14, and the wavelength λ2 is output to the output line 243. The optical signal of the wavelength λ2 output to the output line 243 is input to the optical filter 242.
On the other hand, an optical signal having the same wavelength as the wavelength λ1 input from the input terminal 13 is input to the optical filter 242. In the optical filter 242, the wavelength λ1 and the wavelength λ2 are multiplexed, and a wavelength multiplexed light in which the wavelength λ1 and the wavelength λ2 are multiplexed is output to the output terminal 15. That is, the wavelength λ
One optical signal is demultiplexed and output, and another optical signal of wavelength λ1 can be multiplexed from the input terminal 13.

[0005]

However, when the Mach-Zenda type filter is constituted by a quartz optical waveguide,
The interval between the wavelength λ1 and the wavelength λ2 is several nanometers or less due to its structural limitation. Further, since the transmission characteristics are sinusoidal with respect to the wavelength, it is not possible to set a wavelength bandwidth in which the transmission characteristics are flat in a wide range. Further, a peak of the transmittance periodically exists. In an optical communication system using wavelength division multiplexing, 1.5
When a plurality of signal wavelengths are set at a wavelength interval of, for example, 1 nm or less in the micrometer band, the Mach-Zenda type filter is effective. However, even in the wavelength range from 1.2 micrometers to 1.6 micrometers, the transmission loss in optical fibers is generally less than a few decibels per kilometer, and a wide range of applications is conceivable. In this case, Mach
For a twinda filter, 1.2 micrometers to 1.6
The wavelength band cannot be set in a wide wavelength range of micrometers. The Mach-Zenda type filter is
High-precision control is necessary, for example, it is necessary to change the optical path length difference using a thin film heater or the like to adjust the phase. In addition, separate filters are required for demultiplexing and combining specific wavelengths.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and a first object of the present invention is to provide an optical multiplexing / demultiplexing apparatus capable of demultiplexing and multiplexing a wavelength-multiplexed optical signal with a simple configuration. The purpose is to:

A second object is to provide an optical multiplexing / demultiplexing device capable of multiplexing and demultiplexing in a wide wavelength band.

A third object is to provide an optical multiplexing / demultiplexing device capable of multiplexing and demultiplexing light of multiple wavelengths.

A fourth object of the present invention is to provide an optical multiplexing / demultiplexing device capable of multiplexing and demultiplexing light of multiple wavelengths in a wide wavelength band.

A fifth object of the present invention is to provide an optical multiplexing / demultiplexing device which can be changed to a transmission type or reflection type optical filter having different characteristics depending on a position where light is incident.

A sixth object is to provide an optical multiplexer / demultiplexer capable of dropping / inserting an electric signal with a simple configuration.

A seventh object is to provide an optical transmission system capable of performing bidirectional optical transmission using a plurality of optical multiplexer / demultiplexers connected in a ring.

An eighth object is to provide an optical transmission system capable of bidirectional optical transmission over a plurality of rings.

A ninth object is to provide an optical transmission system capable of bidirectional optical transmission by connecting a multi-wavelength optical multiplexer / demultiplexer and a plurality of optical multiplexers / demultiplexers in a ring.

[0015]

Means for Solving the Problems The object of the present invention is to solve the above problems.
In order to achieve the optical multiplexer / demultiplexer according to the present invention, a wavelength-division multiplexed optical input terminal for inputting a wavelength-multiplexed optical signal, an insertion optical input terminal for inputting an optical signal having a wavelength within a predetermined band,
Among the optical signals input to the wavelength multiplexing optical input terminal, the optical signal having a wavelength within the predetermined band is transmitted, the optical signals having other wavelengths are reflected, and the optical signal input to the insertion optical input terminal is An optical filter that transmits a signal, a branch optical output terminal that is input from the wavelength multiplexing optical input terminal and outputs the optical signal that is transmitted by the optical filter, and an optical filter that is input from the wavelength multiplexing optical input terminal and An optical multiplexing / demultiplexing apparatus comprising: a multiplexed light output terminal that multiplexes and outputs the optical signal reflected by the optical signal and the optical signal input from the insertion optical input terminal and transmitted by the optical filter.
The optical filter has different filter characteristics on the surface.
Change the installation position or light incident position
Then, the filter characteristics are switched.

An optical multiplexer / demultiplexer according to the next invention has a wavelength multiplexing optical input terminal for inputting a wavelength multiplexed optical signal, an insertion optical input terminal for inputting an optical signal having a wavelength within a predetermined band, and a wavelength multiplexing light. An optical filter that reflects an optical signal of a wavelength within a predetermined band among optical signals input to an input terminal, transmits an optical signal of other wavelengths, and reflects an optical signal input to an insertion optical input terminal. And a branch optical output terminal for inputting from the wavelength multiplexing optical input terminal and outputting an optical signal reflected by the optical filter; and an optical signal for inputting from the wavelength multiplexing optical input terminal and passing through the optical filter, and an insertion optical input terminal a more inputs, a and an optical signal reflected by the optical filter in the optical multiplexing and demultiplexing device and a combined light output that multiplexes outputs
The optical filter has different filter characteristics on the surface.
Having multiple areas, changing the installation position or light incident position
The filter characteristic is switched.

The optical multiplexer / demultiplexer according to the next invention has
Wavelengths λ1 to λn in predetermined first to n-th bands (n is an integer)
Multiplexed optical signal to which the multiplexed optical signal including the optical signal
An input terminal and a signal within the predetermined first to n-th bands, respectively.
First to n-th insertions for inputting optical signals of wavelengths λ1a to λna
A light input terminal, and a wavelength input to the multiplex optical input terminal.
Reflects optical signals of wavelengths λ1 to λn among multiplexed optical signals
While transmitting optical signals of other wavelengths,
Wavelengths λ1a to λ input to first to n-th insertion optical input terminals
first to n-th optical filters for reflecting na inserted light;
Input from the wavelength multiplexed optical input terminal, and the first to n-th
Optical signals of the wavelengths λ1 to λn reflected by the optical filter
First to n-th branched light output terminals for respectively outputting signals,
Wavelengths λ1 to λn input from the wavelength multiplexing optical input terminal
Of multiplexed light passes through the first to n-th optical filters, respectively.
An optical path, and a wavelength λ1a input from the insertion optical input terminal.
To λna are reflected by the first to nth optical filters.
To the same optical path and pass through this optical path
Multiplexed light output terminal that outputs multiplexed light
An optical multiplexer / demultiplexer comprising: the optical filter,
Installation with multiple areas with different filter characteristics on the surface
Change the filter characteristics by changing the position or light incident position
Configuration.

The optical multiplexer / demultiplexer according to the next invention is the optical multiplexer / demultiplexer.
Filters apply a deposited film deposited on one side of a glass body to another
It is configured to be inserted between the lath body.

An optical multiplexing / demultiplexing device according to the next invention provides an electric signal
Signal input means for inputting a signal, and the electric signal input means
An electrical signal input from the optical signal having a wavelength within the predetermined band.
Electro-optical conversion means for converting the
An optical signal having a wavelength within the predetermined band among the output optical signals
Input optical input terminal for inputting the
The output optical signal having a wavelength within the predetermined band
And a photoelectric conversion means for converting the
You.

[0020]

[0021]

The optical transmission system according to the next invention is characterized in that
In an optical transmission system in which a plurality of optical multiplexing / demultiplexing apparatuses according to [0015] or [0016] are connected in a ring shape and optical transmission is performed by using an optical signal, the optical multiplexing / demultiplexing apparatus uses a demultiplexing / adding wavelength. Are used for mutually performing optical transmission using optical signals of wavelengths within the same predetermined band.

In the optical transmission system according to the next invention, the step
A plurality of optical multiplexing / demultiplexing apparatuses according to [0015] or [0016] are connected in a ring shape, a plurality of rings are formed, the rings are connected to each other, and light is mutually transmitted using an optical signal. 2. Description of the Related Art In an optical transmission system for transmission, optical multiplexing / demultiplexing devices mutually perform optical transmission using optical signals having wavelengths within a predetermined band having the same demultiplexing / adding wavelength.

The optical transmission system according to the next invention provides the optical transmission system according to the above paragraph [0015] or [0] for performing optical multiplexing / demultiplexing of a single wavelength.
016], a plurality of single-wavelength optical multiplexing / demultiplexing devices are connected to each other in a ring shape using the multi-wavelength optical multiplexing / demultiplexing device according to paragraph [0017], which performs multi-wavelength optical multiplexing / demultiplexing. In an optical transmission system in which a single-wavelength optical multiplexer / demultiplexer and a multi-wavelength optical multiplexer / demultiplexer mutually transmit an optical signal using an optical signal, the optical multiplexer / demultiplexer has a wavelength within a predetermined band in which the demultiplexing and insertion wavelengths are the same. The optical signals are mutually transmitted using the optical signals.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 In this embodiment, multiplexed light is made incident on a transmission filter, and light is made incident from a surface opposite to the incident surface to constitute an optical multiplexer / demultiplexer. FIG. 1 shows an example of the present embodiment. A wavelength division multiplexed signal having three wavelengths of λ1, λ2, and λ3 is input, a wavelength signal of λ1 is demultiplexed, and a wavelength signal of λ1a is inserted and multiplexed. And outputs a wavelength multiplexed signal. In FIG. 1, paths are indicated by lines for three wavelengths for easy understanding of the operation.

In the figure, reference numeral 11 denotes an input terminal of a wavelength multiplexed signal having three wavelengths of λ1, λ2, and λ3, and reference numeral 12 denotes a transmission filter which has transmission characteristics shown in FIG. 2 and transmits wavelength signal light of λ1, λ1a. , Λ2 and λ3 are reflected. Reference numeral 13 denotes an input terminal for light to be inserted / combined. This terminal is arranged so that multiplexed light is incident from a surface opposite to a surface on which light from the input terminal 11 is incident on the transmission filter 12. The terminals 13 are arranged so that the incident angles from the back surface of the transmission filter become the same. Thus, even if an optical signal is input from any surface, the wavelength transmittance characteristics are the same. Reference numeral 14 denotes an output terminal of the demultiplexed light, and reference numeral 15 denotes an output terminal of the wavelength multiplexed signal.

FIG. 2 shows the transmittance characteristics of the transmission filter 12. When the transmission center wavelength of the transmission filter 12 is λB1 and the transmission wavelength bandwidth is 2ΔλB1, the signal wavelength λ1, the signal wavelength λ1a, the transmission center wavelength λB1, and the transmission wavelength bandwidth 2ΔλB1
Is set so as to satisfy λB1−ΔλB1 <λ1 <λB1 + ΔλB1 λB1-ΔλB1 <λ1a <λB1 + ΔλB1. The signal wavelength λ1 and the signal wavelength λ1a need to have substantially the same value, but each may be within the range of the bandwidth 2ΔλB1. Also,
The transmission characteristics of the transmission filter at the signal wavelengths λ2 and λ3 are almost total reflection.

Next, the operation will be described. Input terminal 1
The three wavelength multiplexed signals λ1, λ2, λ3 from FIG.
The transmission type filter 12 having the transmittance characteristic shown in FIG.
One wavelength signal light is transmitted, and the wavelength signal lights of λ2 and λ3 are reflected. The transmitted wavelength signal light of λ1 is output from the output terminal 14 provided on the transmitted light path. On the other hand, the signal light having the wavelength of λ1a from the input terminal 13 is transmitted through the transmission filter 12, and the transmitted light path is made to coincide with the reflected light path of the reflected wavelength multiplexed signal of λ2 and λ3. λ3
The optical signal of wavelength λ1a is inserted and multiplexed into the wavelength multiplexed signal light, and output from an output terminal 15 provided on the optical path.
As described above, the wavelength signal light of λ1 is demultiplexed from the wavelength multiplexed signal light by one transmission filter, and the wavelength signal light of λ1a is inserted and multiplexed into the wavelength multiplexed signal light. The device can be configured.

Next, FIG. 3 shows a specific example of the configuration of the optical multiplexer / demultiplexer. In the figure, a transmission filter 12 is made of an optically transparent material in a wavelength band sufficiently wider than wavelengths λ1 to λ3,
For example, a dielectric multilayer film is formed on the surface of a glass body 55 having a triangular prism shape by vapor deposition so as to have the transmission characteristics shown in FIG. Then, it is sandwiched and fixed with a glass body 55 having the same shape as this. The input terminal 11 is formed by fusing an optical fiber to the surface of the glass body 55 so that the input light irradiates the transmission filter 12 to form the input terminal 11.
The input terminal 13 illuminates the glass body 5 so that the input light irradiates the transmission filter 12 and the incident angle is the same as the incident angle of the light transmitted from the input terminal 11 through the transmission filter 12.
The input terminal 13 is formed by fusing an optical fiber to the surface of the substrate 5.

The output terminal 14 is formed by fusing an optical fiber on the surface of the glass body 55 so that the light from the input terminal 11 passes through the transmission filter 12 and exits to the output terminal 14. The output terminal 15 is placed on the surface of the glass body 55 so that the light path from the input terminal 11 is reflected by the transmission filter 12 and the light path from the input terminal 13 is transmitted through the transmission filter 12. The output terminal 15 is formed by fusing the fiber. In addition, the transmission type filter 12
By using a dielectric multilayer film, the number of layers, the thickness of each layer, by changing the refractive index, the transmission wavelength bandwidth of the transmission filter is 10 nm or more, and for example, a wide range of 1.2 to 1.6 micrometers , Can be arbitrarily set in the wavelength range described above, so that an optical signal wavelength-multiplexed in a wide range of wavelength bands can be demultiplexed and multiplexed.

Embodiment 2 In Embodiment 1, a transmission filter is used, but in this embodiment, an optical multiplexer / demultiplexer is configured using a reflection filter. FIG. 4 shows an example of the present embodiment. In the figure, reference numeral 14 denotes an output terminal of the demultiplexed light, 15 denotes an output terminal of the multiplexed light, 31 denotes a reflection type filter, which has the transmission characteristics shown in FIG. 5 and reflects the wavelength signal light of λ1, λ1a; Transmits signal light of wavelength λ3. 1
Reference numeral 3 denotes an input terminal for light to be inserted / combined. This terminal is arranged so that multiplexed light is incident from a surface opposite to a surface on which light from the input terminal 11 is incident on the reflection type filter 31. The terminals 13 are arranged so that the incident angles from the back surface of the reflection type filter are the same. Others are the same as those in FIG.

FIG. 5 shows the transmittance characteristics of the reflection type filter 31. When the reflection center wavelength of the reflection type filter 31 is λB1 and the reflection bandwidth is 2ΔλB1, the relationship among the signal wavelength λ1, the signal wavelength λ1a, the reflection center wavelength λB1, and the reflection bandwidth 2ΔλB1 is λB1−ΔλB1 <λ1 <λB1 + It is set so that ΔλB1 λB1-ΔλB1 <λ1a <λB1 + ΔλB1 is satisfied. The signal wavelength λ1 and the signal wavelength λ1a need to have substantially the same value, but each may be within the range of the bandwidth 2ΔλB1. Also,
The transmission characteristics of the reflection type filter at the signal wavelength λ2 and the signal wavelength λ3 are almost all transmission.

Next, the operation will be described. Input terminal 1
The three wavelength multiplexed signals λ1, λ2, λ3 from FIG.
The reflection type filter 31 having the transmittance characteristic shown in FIG.
The wavelength signal light of one wavelength is reflected, and the wavelength signal lights of λ2 and λ3 are transmitted. The reflected wavelength signal light of λ1 is output from the output terminal 14 provided on the reflected light path. On the other hand, the wavelength signal light of λ1a from the input terminal 13 is reflected by the reflection type filter 31, and the wavelength of λ1a is matched by matching the reflected light path with the transmitted light path of the transmitted wavelength multiplexed signal light of λ2 and λ3. The signal light and the wavelength multiplexed signal light of λ2 and λ3 are inserted and multiplexed, and output from an output terminal 15 provided on the optical path. As described above, the wavelength signal light of λ1 is demultiplexed from the wavelength multiplexed signal light by one reflection type filter, and the wavelength signal light of λ1a is inserted and multiplexed into the wavelength multiplexed signal light. A wave device can be configured.

Next, FIG. 6 shows a specific example of the configuration of the optical multiplexer / demultiplexer. In the figure, a reflective filter 31 is formed by vapor deposition on a surface of an optically transparent material, for example, a glass body 55 having a triangular prism shape in a wavelength band sufficiently wider than the wavelengths λ1 to λ3 so as to have a transmission characteristic shown in FIG. A dielectric multilayer film is formed, and is fixed by being sandwiched between glass bodies 55 having the same shape. The input terminal 11 is formed by fusing an optical fiber to the surface of the glass body 55 so that the input light irradiates the reflective filter 31 to form the input terminal 11. Input terminal 1
3, an optical fiber is applied to the surface of the glass body 55 so that the input light irradiates the reflective filter 31 and the incident angle is the same as the incident angle of the light transmitted through the reflective filter 31 from the input terminal 11. The input terminal 13 is formed by fusion.

The output terminal 14 is formed by fusing an optical fiber on the surface of the glass body 55 so that the light from the input terminal 11 is reflected by the reflection type filter 31 and emitted to the output terminal 14. The output terminal 15 is placed on the surface of the glass body 55 so that the light path from the input terminal 11 is transmitted through the reflective filter 31 and the light path from the input terminal 13 is reflected from the reflective filter 31. The output terminal 15 is formed by fusing the fiber. Further, the reflection type filter 31
By using a dielectric multilayer film, the number of layers, the thickness of each layer, and the refractive index are changed so that the transmission wavelength bandwidth of the reflective filter 31 is 10 nm or more, and for example, 1.2 μm to 1.6 μm. Since it can be set arbitrarily in a wide wavelength range, it is possible to demultiplex and multiplex an optical signal wavelength-multiplexed in a wide wavelength band.

Embodiment 3 In this embodiment, a multi-wavelength optical multiplexer / demultiplexer is constructed by using a plurality of reflection filters. FIG. 7 shows an example of the present embodiment.
1, λ2, λ3, λ4 wavelength signals are input, λ1, λ2, λ
3, while splitting the wavelength signal of λ4, λ1a, λ2a, λ3a,
An example is shown in which a wavelength signal of λ4a is inserted and multiplexed and output. In the figure, reference numeral 109 denotes an input terminal of a wavelength-division multiplexed signal light, and in this embodiment, a case where signals of four wavelengths of λ1, λ2, λ3, and λ4 are multiplexed is shown. The input light is wavelength-multiplexed into one optical fiber and input. 31,3
2, 33, and 34 are reflection filters of wavelengths λ1, λ2, λ3, and λ4, respectively, which are shown in FIGS. 5, 9, 10, and 11, respectively.
Has the transmission characteristics shown in FIG. Then, the reflection filter of λ1 reflects the wavelength signal light of λ1, λ1a, and λ2, λ2a, λ3,
λ3a, λ4, and λ4a wavelength signal light is transmitted.

Similarly, the reflection type filter of λ2 is λ2, λ
2a is reflected, and λ1, λ1a, λ3, λ3a, λ
4, the wavelength signal light of λ4a is transmitted, the reflection filter of λ3 reflects the wavelength signal light of λ3, λ3a, and λ1, λ1a, λ2,
λ2a, λ4, and λ4a wavelength signal light are transmitted. The reflection filter of λ4 reflects the wavelength signal light of λ4, λ4a, and λ1,
λ1a, λ2, λ2a, λ3, and λ3a are transmitted. Reference numerals 101, 102, 103, and 104 denote input terminals of light to be inserted and multiplexed, and light is input from the surface opposite to the surface on which light from the input terminal 109 is incident on the reflective filters 31, 32, 33, and 34, respectively. These input terminals are arranged so that light enters. 105, 106, 107, 108
Is an output terminal for the demultiplexed wavelength signals of λ1, λ2, λ3 and λ4. Reference numeral 110 denotes an output terminal of the wavelength multiplexed signal light, which is arranged on the same optical path as the input light.

FIG. 5, FIG. 9, FIG. 10, and FIG.
It is a transmittance characteristic of the reflection type filter 31, the reflection type filter 32, the reflection type filter 33, and the reflection type filter. The transmission center wavelength of the reflection type filters 31 to 34 is set to λBn (n = 1 to
4), when the transmission wavelength bandwidth is 2ΔλBn (n = 1 to 4), the relationship among the signal wavelength λn, the signal wavelength λna, the transmission center wavelength λBn, and the transmission wavelength bandwidth 2ΔλBn is λBn−ΔλBn <λn <λBn + ΔλBn λBn−ΔλBn <λna <λBn + ΔλBn (n = 1 to 4).

The operation will be described. Input terminal 1 in FIG.
The wavelength-division multiplexed signals of λ1, λ2, λ3, and λ4 from 09 are reflected by the reflection type filter 31 having transmission characteristics shown in FIG.
3, the wavelength signal of λ4 is transmitted and output on the transmitted light path,
The wavelength signal light of 1 is reflected, and the output terminal 10 on the reflected light path is
5 is output. On the other hand, λ inserted from the input terminal 101
The signal light having the wavelength of 1a is reflected by the reflection type filter 31,
By matching the reflected light path with the transmitted light path of the transmitted wavelength signals of λ2, λ3 and λ4, the wavelength signal light of λ1a and the wavelength multiplexed signal light of λ2, λ3 and λ4 are multiplexed. The multiplexed wavelength multiplexed signal light of λ1a, λ2, λ3, and λ4 is output to the reflection filter 32.

The reflection type filter 32 having the transmission characteristics shown in FIG. 9 transmits the wavelength signal light of λ1a, λ3, λ4 of the input light, outputs it on the transmission light path, reflects the wavelength signal light of λ2,
The signal is output to the output terminal 106 on the reflected light path. On the other hand, the signal light having a wavelength of λ2a input from the input terminal 102 is reflected by the reflection type filter 32, and the reflected light path matches the transmitted light path of the transmitted wavelength multiplexed signal light of λ1a, λ3, λ4. By this, the wavelength signal light of λ2a is converted to λ1a, λ3,
It is inserted and multiplexed into the wavelength multiplexed signal light of λ4. Then, the multiplexed wavelength multiplexed signals of λ1a, λ2a, λ3, and λ4 are output to the reflection filter 33. Similarly, the same operation is repeated in the reflection type filter 33 and the reflection type filter 34 having the transmission characteristics shown in FIGS.
05, output terminal 106, output terminal 107, output terminal 10
8 outputs wavelength signals of λ1, λ2, λ3, λ4, respectively, and an output terminal 110 outputs wavelength multiplexed signals of λ1a, λ2a, λ3a, λ4a. That is, by using a plurality of reflection filters, optical multiplexing and optical demultiplexing of multiple wavelengths can be performed.

Next, FIG. 8 shows a specific configuration example of the optical multiplexer / demultiplexer. In the figure, reflection filters 31, 32,
33, 34 are provided on the surface of an optically transparent material, for example, a glass body 55 having a triangular prism shape in a wavelength band sufficiently wider than the wavelengths λ1 to λ4, and the transmission characteristics shown in FIGS. A dielectric multilayer film is formed by vapor deposition so as to have
Then, it is sandwiched and fixed with a glass body 55 having the same shape as this. The input terminal 109 is formed by fusing an optical fiber to the surface of the glass body 55 so that the input light is output to the output terminal 110 when the input light passes through the reflection type filters 31, 32, 33, and 34. Input terminal 10
1, 102, 103, and 104 irradiate the reflection type filters 31, 32, 33, and 34 with the input light, and the incident angles of the reflection type filters 31, 32, and 3 from the input terminal 109.
An optical fiber is fused to the surface of the glass body 55 so as to have the same angle of incidence of the light transmitted through
102, 103 and 104 are formed.

Output terminals 105, 106, 107, 108
Indicate that the light from the input terminal 109 is reflected by the reflection type filters 31 and 3
2, 33, and 34 and output terminals 105, 106, and 10
Optical fibers are fused onto the surfaces of the four glass bodies 55 so that the output terminals 105, 106, 1
07 and 108 are formed. The output terminal 110 is configured to transmit light from the input terminal 109 to the reflection type filters 31, 32, 33, 3.
4 and the input terminals 101, 102, 10
The light from 3, 104 is reflected by the reflection filters 31, 32, 3
An optical fiber is fused on the surface of the glass body 55 so as to coincide with the optical path reflecting the light beams 3 and 34 to form the output terminal 110. Further, by changing the number of layers of the dielectric multilayer film, the thickness of each layer, and the refractive index of the reflective filters 31, 32, 33, and 34 as described above, the wavelength bandwidth of the reflective filters is increased to 10 nm or more. And can be set arbitrarily in a wide wavelength range of, for example, 1.2 μm to 1.6 μm.

Embodiment 4 This embodiment is intended to switch to different transmission characteristics by changing the position of the reflection type filter. FIG. 12 shows an embodiment of the present invention.
And FIG. In FIG. 12, 141 is a reflection type filter, and FIG. 13 shows a state seen from the front.
Others are the same as those in FIG. Reflective filter 141
Is configured such that an upper half area and a lower half area are switched and arranged on the optical path of input light. The upper half region has a characteristic of reflecting only optical signals in a wavelength band including the signal wavelengths λ1 and λ1a and transmitting optical signals in other wavelength bands. FIG. 5 shows the characteristics. The lower half region has a characteristic of reflecting only optical signals in a wavelength band including the signal wavelength λ2 and the signal wavelength λ2a and transmitting optical signals in other wavelength bands. FIG. 9 shows the characteristics.

In FIG. 12, the input light from the input terminal 11 shows a case where signals of three wavelengths λ1, λ2, and λ3 are multiplexed, and is input to one optical fiber after being multiplexed. . The upper half area of the reflection filter 141 is arranged on the optical path of the input light. Reflective filter 141
The wavelength signal lights of λ2 and λ3 of the input light input to the upper half region are transmitted and output to the output terminal 15 on the transmission optical path. The wavelength signal light of λ1 is reflected by the reflection type filter 1.
The light is reflected at 41 and output to the output terminal 14 on the reflected light path. From the input terminal 13, a wavelength signal of λ1a is input. According to the transmittance characteristic of the upper half region of the reflection filter 141, the wavelength signal light of λ1a is reflected by the reflection filter 141. At this time, the optical path of the input light is set so that the wavelength signal of λ1a is output on the same optical path as the wavelength signals of λ2 and λ3. Therefore, the wavelength signals of λ1a, λ2, and λ3 are wavelength-multiplexed on the same optical path and output from the output terminal 15.

Next, FIG. 14 shows a case where the lower half area of the reflection filter 141 has been moved so as to be arranged on the optical path of the input light. In this case, the lower half region of the reflection filter 141 has a characteristic of reflecting only optical signals in a wavelength band including the signal wavelength λ2 and the signal wavelength λ2a and transmitting optical signals in other wavelength bands. When an optical signal having a signal wavelength of λ2a is input from 13, the wavelength signals of λ1, λ2a, and λ3 are wavelength-multiplexed on the same optical path and output from the output terminal 15. By changing the position held by the reflective filter 141 in this manner, a plurality of wavelength bands for multiplexing and demultiplexing can be provided.

In the above example, the reflection type filter 141 has different transmission characteristics in the upper and lower halves of the entire area, and the reflection type filter 141 is moved in the linear direction. By rotating the reflective filter 171 having a plurality of different transmission characteristics formed thereon, a plurality of wavelength bands can be similarly multiplexed and demultiplexed even when the incident position of the optical signal is moved. The same effect can be obtained by using a transmission filter instead of the reflection filters 141 and 171. Further, an example has been described in which switching is performed by giving different transmission characteristics to two locations on the reflective filter, but switching may be performed by giving different transmission characteristics to two or more locations.

Embodiment 5 In this embodiment, an electric signal is converted into an optical signal, input to an optical multiplexer / demultiplexer, and optically multiplexed. The optical multiplexer / demultiplexer converts the optical signal demultiplexed from the multiplex into an electric signal. It is converted and output. FIG. 16 illustrates an embodiment of the present invention, in which 195 is input information, 196 is a laser diode control circuit, 197 is a laser diode, 198 is a control signal, 191 is a photodiode, and 192 is an output signal. , 193 are receiving circuits, 19
4 is output information. Others are the same as those in FIG. In this embodiment, the input light from the input terminal 11 is λ1,
The figure shows a case where signals of three wavelengths λ2 and λ3 are multiplexed, and the signals are multiplexed and input to one optical fiber.
The reflection type filter 31 has the transmittance characteristic shown in FIG. 5, and is arranged on the optical path of the input light.

The wavelength signals of λ2 and λ3 of the input light input to the reflection filter 31 are transmitted and output on the transmitted light path. The wavelength signal of λ1 is reflected by the reflection type filter 31.
And is output on the reflected light path. On the reflected light path, a photodiode 191 is disposed as an electro-optical conversion means for receiving an optical signal of the signal wavelength λ1 and outputting an electric signal, and an output signal 192 from the photodiode 191 is provided.
Is input to the receiving circuit 193. From the receiving circuit 193, the electric signal component carried in the optical signal having the signal wavelength λ1 is output to the outside as output information 194.

In order to insert certain information as an optical signal on the transmission line, the information signal to be inserted is input to the laser diode control circuit 196 as input information 195. The laser diode control circuit 196 includes a control signal 1 for driving a laser diode 197 as an electro-optical converter.
98 is output. The laser diode 197 receives the control signal 198, which is an electric signal, and converts the electric signal component into λ
The optical signal carried by the optical signal having the signal wavelength of 1a is output.
The output light is input to the reflection filter 31. The signal wavelength λ1a reflects from the reflective filter 31 according to the transmittance characteristics of the reflective filter 31. At this time, the signal wavelength λ1a is
The optical path of the input light, that is, the position of the light emitting point of the laser diode 197 and the emission direction are set so as to be output on the same optical path as the signal wavelengths λ2 and λ3. Therefore, the signal wavelengths λ1a, λ2, and λ3 are wavelength-multiplexed on the same optical path and output from the output terminal 15.

As described above, the electric signal is converted into light, multiplexed into multiplexed light, the light split from the multiplexed light is converted into an electric signal, and the multiplexed light is multiplexed as it is. Multiplex transmission over a wider band. Although the case where the reflection type filter 31 is used as the wavelength demultiplexing means has been described, the transmission type filter 12 may be used.
In this case, the position of the output terminal of the wavelength division multiplexed light and the position of the electro-optical conversion means may be changed. FIG. 17 shows a transmission filter 1.
2 shows a configuration diagram in the case of using 2.

Embodiment 6 In this embodiment, a plurality of optical multiplexing / demultiplexing devices are connected in a ring via an optical fiber, and the optical multiplexing / demultiplexing devices mutually use optical signals within the same wavelength band to each other. It enables communication. FIG. 18 is a block diagram illustrating an example of configuring an optical communication system using eight optical multiplexer / demultiplexers. In the figure, reference numerals 211 to 218 denote optical multiplexing / demultiplexing devices using the reflection type filters shown in FIGS. 219 is an optical fiber. The other parts are the same as those in FIGS. 4 and 6 and will not be described. The optical multiplexing / demultiplexing device 211 and the optical multiplexing / demultiplexing device 215 reflect the characteristic of FIG. 5 that reflects the wavelength signal λ1, and the optical multiplexing / demultiplexing device 212 and the optical multiplexing / demultiplexing device 216 reflect the characteristic of FIG. And the optical multiplexing / demultiplexing device 213 and the optical multiplexing / demultiplexing device 217
The optical multiplexer / demultiplexer 214 and the optical multiplexer / demultiplexer 218 have the characteristic shown in FIG. 11 that reflects the wavelength signal λ4.

The output terminal 15 of the optical multiplexer / demultiplexer 211 is connected to the input terminal 11 of the optical multiplexer / demultiplexer 212 by an optical fiber 219.
Connected to. The output terminal 15 of the optical multiplexer / demultiplexer 212 is connected to the input terminal 1 of the optical multiplexer / demultiplexer 213 by an optical fiber 219.
Connected to 1. Similarly, all the optical multiplexer / demultiplexers of the optical multiplexer / demultiplexer 211 to the optical multiplexer / demultiplexer 218 are connected in a ring shape.

Next, the operation between the optical multiplexer / demultiplexer 211 and the optical multiplexer / demultiplexer 215 will be described. Optical multiplexer / demultiplexer 211
Is λ inputted to the input terminal 13 in the reflection type filter.
The signal light having the wavelength of 1 is reflected and output to the output terminal 15.
The optical multiplexer / demultiplexers 212, 213, and 214 transmit the signal light having the wavelength of λ1 input to the respective input terminals 11 and output the signal light to the output terminal 15. The optical multiplexer / demultiplexer 215 reflects the signal light having the wavelength of λ1 input to the input terminal 11 and outputs the signal light to the output terminal 14. Accordingly, the signal light having the wavelength of λ1 input to the input terminal 13 of the optical multiplexer / demultiplexer 211 is output to the output terminal 14 of the optical multiplexer / demultiplexer 215.

The optical multiplexer / demultiplexer 215 reflects the signal light having the wavelength of λ1a input to the input terminal 13 and outputs the signal light to the output terminal 15. The optical multiplexer / demultiplexers 216, 217, and 218 transmit the signal light having the wavelength of λ1a input to the respective input terminals 11, and output the signal light to the output terminal 15. Optical multiplexer / demultiplexer 211
Reflects the signal light having the wavelength of λ1a input to the input terminal 11 and outputs the signal light to the output terminal 14. Therefore, the optical multiplexer / demultiplexer 2
The signal light having a wavelength of λ1a input to the input terminal 13 of the fifteen is output to the output terminal 14 of the optical multiplexer / demultiplexer 211. That is,
By using the signal wavelength λ1a and the signal wavelength λ1 between the optical multiplexing / demultiplexing device 211 and the optical multiplexing / demultiplexing device 215, two-way communication becomes possible.

Similarly, signal wavelengths λ2a to λ4a, λ2 to λ4
, Two-way communication is possible between the optical multiplexer / demultiplexer 212 and the optical multiplexer / demultiplexer 216, the optical multiplexer / demultiplexer 213 and the optical multiplexer / demultiplexer 217, and the optical multiplexer / demultiplexer 214 and the optical multiplexer / demultiplexer 218. In this example, a reflection-type filter is used for each of the optical multiplexer / demultiplexers 211 to 218, but a transmission-type filter may be used. Further, in the above example, the case where four wavelength bands are set has been described. However, even if the number of wavelengths is increased, the two-way optical multiplexer / demultiplexer arranged on the ring-shaped transmission line has the same principle even if the number of wavelengths is increased. Can communicate.

Embodiment 7 In this embodiment, two ring-shaped communication paths constituted by a plurality of optical multiplexing / demultiplexing devices are provided.
The ring-shaped communication paths are connected to communicate with each other. FIG. 19 shows a configuration example of an inter-ring connection type communication system that connects two ring communication paths and uses an optical multiplexing / demultiplexing device. In the figure, reference numeral 40 denotes a first ring constituting a ring communication path, and eight optical multiplexing / demultiplexing devices 211 to 211 are provided.
218 are connected by an optical fiber 219 in a ring shape. Reference numeral 40a denotes a second ring constituting a ring-shaped communication path, in which eight optical multiplexer / demultiplexers 211a to 218a are connected in a ring shape by an optical fiber 219. The first ring 40 and the second ring 40a are the same as those shown in the sixth embodiment. That is, in the first ring 40, between the optical multiplexer / demultiplexer 211 and the optical multiplexer / demultiplexer 215,
By using the signal wavelength λ1a and the signal wavelength λ1, bidirectional communication can be performed. Also, using the signal wavelengths λ2a to λ4a and the signal wavelengths λ2 to λ4, respectively, the optical multiplexer / demultiplexer 212 and the optical multiplexer / demultiplexer 216, the optical multiplexer / demultiplexer 213 and the optical multiplexer / demultiplexer 217, and the optical multiplexer / demultiplexer 214 and the optical multiplexer / demultiplexer are used. Two-way communication can be performed between the wave devices 218.

Similarly, in the second ring 40a, bidirectional communication can be performed between the optical multiplexing / demultiplexing device 211a and the optical multiplexing / demultiplexing device 215a by using the signal wavelength λ1a and the signal wavelength λ1. Further, the signal wavelengths λ2a to λ4a and the signal wavelengths λ2 to λ
4, the optical multiplexer / demultiplexer 212a and the optical multiplexer / demultiplexer 216a, and the optical multiplexer / demultiplexer 213a and the optical multiplexer / demultiplexer 21
7a, bidirectional communication can be performed between the optical multiplexer / demultiplexer 214a and the optical multiplexer / demultiplexer 218a. Next, the output terminal 14 of the optical multiplexer / demultiplexer 215 connected to the first ring 40 is connected by an optical fiber 219 to the input terminal 13 of the optical multiplexer / demultiplexer 211a connected to the second ring 40a. The output terminal 14 of the optical multiplexer / demultiplexer 211a is connected to the input terminal 13 of the optical multiplexer / demultiplexer 215 via an optical fiber 219.

The operation will be described. First ring 40
Is input to the input terminal 13 of the optical multiplexer / demultiplexer 211, the signal of wavelength λ1 is output to the output terminal 15 of the optical multiplexer / demultiplexer 211, and the first ring 40 is moved counterclockwise. In the circumferential direction, the optical multiplexer / demultiplexer 212, 213, 21
4 and is output to the output terminal 14 of the optical multiplexer / demultiplexer 215. The output terminal 14 of the optical multiplexer / demultiplexer 215 is connected to the input terminal 13 of the optical multiplexer / demultiplexer 211a of the second ring, and the signal wavelength λ1 input to the optical multiplexer / demultiplexer 211a is transmitted through the second ring 40a. The light is output from the output terminal 14 of the optical multiplexing / demultiplexing device 215a in the counterclockwise direction via the optical multiplexing / demultiplexing devices 212a, 213a, and 214a.

On the other hand, the input terminal 1 of the optical multiplexer / demultiplexer 215a
The signal light having the wavelength of λ1a input to
The ring 40a of the optical multiplexer / demultiplexer 21 in the counterclockwise direction.
6a, 217a, and 218a, output to the output terminal 14 of the optical multiplexer / demultiplexer 211a, further input to the input terminal 13 of the optical multiplexer / demultiplexer 215 of the first ring 40, and output to the optical multiplexer / demultiplexer 216, 217, 218 through the optical multiplexer / demultiplexer 21
1 output terminal 14. Therefore, two-way communication can be performed between the optical multiplexing / demultiplexing device 211 and the optical multiplexing / demultiplexing device 215a arranged in two different ring transmission paths by using the signal wavelength λ1a and the signal wavelength λ1.

Embodiment 8 This embodiment relates to an optical multiplexer / demultiplexer having one wavelength (hereinafter simply referred to as an optical multiplexer / demultiplexer) and an optical multiplexer / demultiplexer having a plurality of wavelengths (hereinafter referred to as a multi-wavelength optical multiplexer / demultiplexer). ) To form a ring type optical communication system capable of bidirectional communication of a plurality of lines. FIG.
Reference numeral 0 indicates an example in which a ring-type optical communication system is configured using one multi-wavelength optical multiplexer / demultiplexer and four optical multiplexers / demultiplexers. In the figure, reference numeral 231 denotes the four-wavelength multi-wavelength optical multiplexer / demultiplexer described in the third embodiment. Reference numerals 211 to 214 denote the optical multiplexing / demultiplexing devices described in the second embodiment, which use the reflection type filters shown in FIGS. 219 is an optical fiber. The other parts are the same as those in FIGS. 4 and 6 and will not be described.

The optical multiplexer / demultiplexer 211 has the characteristic shown in FIG. 5 for reflecting the wavelength signal λ1, the optical multiplexer / demultiplexer 212 has the characteristic shown in FIG. 9 for reflecting the wavelength signal λ2, and the optical multiplexer / demultiplexer 213 has the characteristic shown in FIG.
The optical multiplexer / demultiplexer 214 has the characteristic shown in FIG. 11 that reflects the wavelength signal λ3 and the characteristic shown in FIG. 11 that reflects the wavelength signal λ4. The output terminal 11 of the multi-wavelength optical multiplexer / demultiplexer 231
0 is connected to the input terminal 11 of the optical multiplexer / demultiplexer 211 by an optical fiber 219, and the output terminal 15 of the optical multiplexer / demultiplexer 211 is connected to the input terminal 11 of the optical multiplexer / demultiplexer 212 by an optical fiber 219. Similarly, the optical multiplexing / demultiplexing device 2
12 and the input terminal 1 of the optical multiplexer / demultiplexer 213
1 is an output terminal 15 of the optical multiplexer / demultiplexer 213 and an input terminal 11 of the optical multiplexer / demultiplexer 214 is an optical fiber 219
Is connected. The output terminal 15 of the optical multiplexer / demultiplexer 214 is connected to the input terminal 109 of the multi-wavelength optical multiplexer / demultiplexer 231.
Connected to. That is, the multi-wavelength optical multiplexer / demultiplexer 231 and the optical multiplexer / demultiplexers 211 to 214 form a ring-shaped communication path.

The multi-wavelength optical multiplexing / demultiplexing device 231 receives signal lights of wavelengths λ1a to λ4a from the four input terminals 101 to 104,
The light is reflected by the reflection filter, wavelength-multiplexed on the same optical path, and output from the output terminal 110. Next, the optical multiplexer / demultiplexer 211 is connected to the output terminal 11 of the multi-wavelength optical multiplexer / demultiplexer 231.
Of the wavelength signals of signal light having wavelengths of λ1a to λ4a from 0, λ
1a is reflected and output to the output terminal 14, and λ2
Signal light of wavelengths a, λ3a and λ4a is transmitted.

The optical multiplexer / demultiplexer 211 has an input terminal 1
Λ2 which reflects and transmits the signal light of wavelength λ1 input to 3
The signal is output to the output terminal 15 together with the signal light having the wavelengths of a, λ3a, and λ4a. The optical multiplexing / demultiplexing device 212 reflects only the wavelength signal λ2a of the signal light having the wavelengths of λ1, λ2a, λ3a, and λ4a from the output terminal 15 of the optical multiplexing / demultiplexing device 211, outputs the signal to the output terminal 14, and outputs λ1, λ3a , Λ4a. Further, the optical multiplexer / demultiplexer 212 reflects the signal light having the wavelength of λ2 input to the input terminal 13 and transmits λ1, λ3a,
The signal is output to the output terminal 15 together with the signal light having the wavelength of λ4a.

Similarly, the optical multiplexer / demultiplexer 213 reflects the signal light having the wavelength of λ3a input to the input terminal 11 and outputs the signal light to the output terminal 14, while also reflecting the λ3 reflected from the input terminal 13 and the transmitted λ1 , Λ2 and λ4a are output to the output terminal 15. The optical multiplexer / demultiplexer 214 reflects the signal light having the wavelength of λ4a input to the input terminal 11, outputs the signal light to the output terminal 14, and reflects the λ4 reflected from the input terminal 13.
Then, the transmitted signal light having the wavelengths of λ1, λ2, and λ3 is output to the output terminal 15.

Therefore, two-way communication is possible between the multi-wavelength optical multiplexer / demultiplexer 231 and the optical multiplexer / demultiplexer 211 by using the signal wavelength λ1a and the signal wavelength λ1. Similarly, the multi-wavelength optical multiplexing / demultiplexing device 231 and the optical multiplexing / demultiplexing device 212, the multi-wavelength optical multiplexing / demultiplexing device 231 and the optical multiplexing / demultiplexing device 213, and the multi-wavelength optical multiplexing / demultiplexing device 23 using the signal wavelengths λ2a to λ4a and λ2 to λ4.
1 and the optical multiplexer / demultiplexer 214 can also perform bidirectional communication. In the above example, a reflection filter is used for the optical multiplexing / demultiplexing devices 211 to 214, but a transmission filter may be used.

[0066]

As described above, according to the present invention, the wavelength signal light of λ1 is demultiplexed from the wavelength-division multiplexed signal light by one transmission filter, and the wavelength signal light of λ1a is inserted / combined into the wavelength-division multiplexed signal light. Since the waves are waved, a compact optical multiplexing / demultiplexing device can be configured.
Furthermore, depending on the position where light is incident, transmission characteristics or reflection characteristics
Multiplexing and demultiplexing with one optical filter.
Wavelength bands can be plural.

According to the next invention , the wavelength signal light of λ1 is demultiplexed from the wavelength multiplexed signal light by one reflection type filter, and the wavelength signal light of λ1a is multiplexed with the wavelength multiplexed signal light. A compact optical multiplexer / demultiplexer can be configured. further,
Change transmission or reflection characteristics depending on the position where light enters
Wavelength band for multiplexing and demultiplexing with one optical filter
Can be multiple.

[0068]

Further , according to the next invention, since a plurality of reflection filters are arranged on the same optical path, multi-wavelength optical multiplexing and optical demultiplexing can be performed. In addition, transmission characteristics depend on the position where light enters.
Or because the reflection characteristics can be changed, one optical filter
Multiple wavelength bands can be combined and demultiplexed.

Further , according to the next invention , the optical filter is constituted by the vapor-deposited film. Therefore, by changing the number of layers, the thickness, and the refractive index of the vapor-deposited film, an optical signal wavelength-multiplexed in a wide wavelength band can be separated. Waves can be combined.

[0071]

Further , according to the next invention, an electric signal is converted into light, multiplexed into multiplexed light, light split from the multiplexed light is converted into an electric signal, and the multiplexed light is multiplexed as it is. Broadband multiplex transmission can be performed by multiplexing with a signal.

According to the next invention, since the optical multiplexing / demultiplexing devices are connected in a ring shape, bidirectional optical transmission can be performed using optical signals in the same wavelength band.

According to the next invention, the optical multiplexer / demultiplexer is connected in the form of a ring, and a plurality of the rings are provided to connect the rings. Can be transmitted.

According to the next invention, the multi-wavelength optical multiplexer / demultiplexer and the plurality of optical multiplexers / demultiplexers are connected in a ring shape.
Bidirectional optical transmission can be performed using optical signals in the same wavelength band.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an optical multiplexer / demultiplexer according to Embodiment 1 of the present invention.

FIG. 2 is a diagram illustrating transmission characteristics of a transmission filter having a wavelength of λ1 according to the first embodiment of the present invention;

FIG. 3 is a configuration diagram of an optical multiplexing / demultiplexing device using a transmission filter sandwiched between glass bodies according to Embodiment 1 of the present invention;

FIG. 4 is a configuration diagram of an optical multiplexing / demultiplexing device according to a second embodiment of the present invention.

FIG. 5 is a diagram illustrating transmission characteristics of a reflective filter having a wavelength of λ1 according to Embodiment 2 of the present invention;

FIG. 6 is a configuration diagram of an optical multiplexing / demultiplexing device using a reflection type filter sandwiched between glass bodies according to Embodiment 2 of the present invention.

FIG. 7 is a configuration diagram of a multi-wavelength optical multiplexer / demultiplexer according to Embodiment 3 of the present invention.

FIG. 8 is a configuration diagram of an optical multiplexing / demultiplexing device using a multi-wavelength reflective filter sandwiched between glass bodies according to Embodiment 3 of the present invention.

FIG. 9 is a diagram illustrating transmission characteristics of a reflective filter having a wavelength of λ2 according to Embodiment 3 of the present invention;

FIG. 10 is a diagram illustrating transmission characteristics of a reflective filter having a wavelength of λ3 according to Embodiment 3 of the present invention;

FIG. 11 is a diagram illustrating transmission characteristics of a reflective filter having a wavelength of λ4 according to the third embodiment of the present invention;

FIG. 12 is a diagram illustrating a state in which an upper half region of a reflection type filter according to Embodiment 4 of the present invention has been moved so as to be disposed on an optical path of input light.

FIG. 13 is a diagram showing a shape of a reflection filter according to Embodiment 4 of the present invention.

FIG. 14 is a view showing a state in which a lower half region of a reflection type filter according to Embodiment 4 of the present invention has been moved so as to be arranged on an optical path of input light.

FIG. 15 is an explanatory diagram of a reflection type filter having a plurality of different transmission characteristics formed on a circle according to the fourth embodiment of the present invention.

FIG. 16 is a configuration diagram of an apparatus for converting an electric signal into light and optically multiplexing the same with an optical multiplexing / demultiplexing apparatus using a reflection filter according to a fifth embodiment of the present invention.

FIG. 17 is a configuration diagram of an apparatus for converting an electric signal into light and optically multiplexing the same with an optical multiplexing / demultiplexing apparatus using a transmission filter according to a fifth embodiment of the present invention.

FIG. 18 is a configuration diagram of a ring-type optical communication system using an optical multiplexer / demultiplexer according to Embodiment 6 of the present invention.

FIG. 19 is a configuration diagram of an inter-ring connection type optical communication system according to a seventh embodiment of the present invention.

FIG. 20 is a configuration diagram of a ring-type optical communication system using a multi-wavelength optical multiplexer / demultiplexer according to an eighth embodiment of the present invention.

FIG. 21 is a configuration diagram of an optical multiplexer / demultiplexer using a conventional optical filter.

FIG. 22 is a diagram for explaining an operation of a conventional optical multiplexer / demultiplexer using an optical filter.

[Explanation of symbols]

 REFERENCE SIGNS LIST 11 input terminal 12 transmission filter 13 input terminal 14 output terminal 15 output terminal 31 reflection filter 55 glass body 101, 102, 103, 104 input terminal 105, 106, 107, 108 output terminal 109 input terminal 110 output terminal 141 reflection type Filter 171 Reflective filter 191 Photodiode 192 Output signal 193 Receiving circuit 194 Output information 195 Input information 196 Laser diode control circuit 197 Laser diode 198 Control signal 211 212, 213, 214 Optical multiplexer / demultiplexer 215 216, 217, 218 Optical multiplexer / demultiplexer Device 219 Optical fiber 231 Optical multiplexer / demultiplexer

Continued on the front page (72) Inventor Takayuki Suga 1-3-1 Gotenyama, Musashino-shi, Tokyo Crystal Park Building NTT Advanced Technology Corporation (72) Inventor Toshihiro Ichikawa Marunouchi, Chiyoda-ku, Tokyo 2-3-2 Mitsubishi Electric Corporation (72) Inventor Naohiko Yasui 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Electric Corporation (56) References JP-A-55-97752 (JP, A) JP-A-55-100761 (JP, A) JP-A-55-34569 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04J 14/00 H04B 10/00 INSPEC (DIALOG) JICST File (JOIS)

Claims (8)

(57) [Claims] 1. A wavelength multiplexed light input terminal for inputting a wavelength multiplexed optical signal, the insertion optical input terminal for receiving an optical signal having a wavelength within a predetermined band
When, among the optical signal inputted to the wavelength division multiplexed light input terminal, and transmitting the optical signal of the wavelength within said predetermined band, while reflecting the optical signal of the other wavelengths are input to the add light input terminal An optical filter that transmits the optical signal, and a branch optical output terminal that is input from the wavelength multiplexing optical input terminal and outputs the optical signal that is transmitted by the optical filter.
And multiplexes the optical signal input from the wavelength multiplexed optical input terminal and reflected by the optical filter and the optical signal input from the insertion optical input terminal and transmitted by the optical filter. optical wavelength division that includes a combined light output
A wave device, wherein the optical filter has a plurality of filters having different filter characteristics on a surface.
The installation position or the light incident position is changed to
Light characterized by switching the filter characteristics
Multi / demultiplexer. Wherein the multi-wavelength light input terminal for inputting a wavelength multiplexed optical signal, the insertion optical input terminal for receiving an optical signal having a wavelength within a predetermined band
And, among the optical signals input to the wavelength multiplexed optical input terminal, reflect an optical signal having a wavelength within the predetermined band, transmit an optical signal having other wavelengths, and input the optical signal to the insertion optical input terminal. an optical filter for reflecting the optical signal, the input from the wavelength-multiplexed light input terminal, the branched light output terminal for outputting the optical signal reflected by said optical filter
And multiplexes the optical signal input from the wavelength multiplexing optical input terminal and transmitted through the optical filter and the optical signal input from the insertion optical input terminal and reflected by the optical filter, and outputs the multiplexed signal. optical wavelength division that includes a combined light output
A wave device, wherein the optical filter has a plurality of filters having different filter characteristics on a surface.
The installation position or the light incident position is changed to
Light characterized by switching the filter characteristics
Multi / demultiplexer. 3. A multiplexed optical input terminal for inputting multiplexed optical signals including optical signals of wavelengths λ1 to λn (n is an integer) within predetermined first to n-th bands , respectively, and 1 to the wavelength λ1a in the n-th band
First to nth insertion optical input terminals for inputting an optical signal of λna
And reflecting the optical signals of wavelengths λ1 to λn among the wavelength-multiplexed optical signals input to the multiplexed optical input terminal, transmitting the optical signals of other wavelengths, and inserting the first to nth insertions. a first through an optical filter of the n reflecting the insertion optical wavelength λ1a~λna input to the optical input terminal is input from the multi-wavelength light input terminal, the first to n
First to n-th branched optical output terminals for respectively outputting the optical signals of the wavelengths λ1 to λn reflected by the optical filter
And wavelengths λ1 to λn input from the wavelength multiplexing optical input terminal.
Optical paths through which the multiplexed light passes through the first to n-th optical filters, respectively, and a wavelength λ1a input from the insertion optical input terminal.
A multiplexed light output terminal for arranging an optical path on which the insertion light of λna is reflected by the first to nth optical filters in the same optical path, and outputting a multiplexed light multiplexed by passing through this optical path.
An optical multiplexer / demultiplexer comprising: a plurality of optical filters having different filter characteristics on a surface.
The installation position or the light incident position is changed to
Light characterized by switching the filter characteristics
Multi / demultiplexer. Wherein said optical filter, constituting the deposited film was deposited on one surface of the glass body, interleave between the other glass body
4. The method according to claim 1, wherein:
3. The optical multiplexer / demultiplexer according to claim 1. 5. A electrical signal input means for inputting an electrical signal, and electrical-optical converter means for converting an electric signal input from the electrical signal input means into an optical signal of wavelength within said predetermined band, the electrical-optical converter and add light input terminal for receiving an optical signal of wavelength within said predetermined band of the optical signal means has outputted, converts the optical signal of the wavelength of the branched light output within the predetermined band output by the terminal to an electric signal a photoelectric conversion means for
Characterized in that it is configured to further comprise, a 請 Motomeko 1
5. The optical multiplexing / demultiplexing device according to any one of the chairs 4. 6. An optical transmission system in which a plurality of optical multiplexing / demultiplexing apparatuses according to claim 1 or 2 are connected in a ring shape, and optical transmission is performed by using an optical signal therebetween. An optical transmission system, wherein optical transmission is performed mutually using optical signals of wavelengths within a predetermined band having the same wave and insertion wavelength. 7. A plurality of optical multiplexing / demultiplexing apparatuses according to claim 1 or 2 are connected in a ring shape, a plurality of rings are formed, and the rings are connected to each other to transmit optical signals to each other. An optical transmission system for performing optical transmission by using the optical multiplexer / demultiplexer, wherein the optical multiplexer / demultiplexer mutually performs optical transmission using optical signals of wavelengths within a predetermined band having the same demultiplexing / adding wavelength. . 8. A claim 3 for a plurality and optical multiplexing-demultiplexing of multi-wavelength light multiplexing and demultiplexing device having a single wavelength according to claim 1 or 2 for optical multiplexing-demultiplexing a single wavelength In an optical transmission system connected in a ring using a multi-wavelength optical multiplexing / demultiplexing device described above, a single-wavelength optical multiplexing / demultiplexing device and a multi-wavelength optical multiplexing / demultiplexing device mutually perform optical transmission using optical signals, An optical transmission system, wherein the optical multiplexing / demultiplexing devices mutually perform optical transmission using optical signals having wavelengths within a predetermined band having the same demultiplexing / adding wavelength.