JPH08313942A - Optical switch used for optical device, optical fiber amplifier and optical filter - Google Patents

Abstract

PURPOSE: To obtain an inexpensive optical amplifier by setting a polarization plane rotating element at a cross state when the polarization plane of transmitted light is not rotated and setting this element at a bar state when the polarization plane of incident light is rotated 90 deg.. CONSTITUTION: This optical switch has the polarization rotating element 1 and a polarized wave separating film 2 in its basic constitution. Light inputs 3, 4 are inputted as P polarized waves (the vibration direction of the electric fields is in parallel with the plane of Fig.). In such a case, the polarization plane rotating element 1 embodied by liquid crystals and Faraday rotator, etc., attains the set of the cross state when the element is set so as not to rotate the polarization plane of the transmitted light. The polarization plane rotating element 1 attains the set of the bar state when the element is set to rotate the polarization plane of the incident light 90 deg.. At this time, the light outputs 5, 6 are outputted as the same polarized wave as the polarized wave of the incident light regardless of the cross or bar state. The bar state is attained in the case where the polarized wave is not rotated by the polarization plane rotating element 1 and the cross state is attained in the case where the polarization plane 15 rotated 90 deg. by the polarization plane rotating element 1 when the light inputs 3, 4 to the switch are polarized to the S polarized waves.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical device and an optical device used in the device, and more particularly to an optical switch in optical communication,
The present invention relates to an optical device used in signal processing using light, optical measurement, and the like, and an optical device such as an optical switch, an optical filter, and an optical amplifier used in the optical device.

[0002]

2. Description of the Related Art As shown in FIGS. 43 (a) and 43 (b), a conventional optical switch using polarization control is used to shift a light beam by using a birefringent plate or a polarization integrated in a complicated shape. A beam splitter with a separation membrane was used (Reference: K.
Noguchi, T. Sakano, T. Matsumoto, "A rearrangeab
le multichannel free-space optical switch based mu
ltistage network configuration ", IEEE, J.of Lightwa
ve Technology vol.9, pp.1726 (1991)).

Further, as shown in FIG. 44, the conventional optical fiber amplifier has been used for optical amplification by using an optical fiber amplifier with one input and one output. Furthermore, at the research stage, arrayed semiconductor amplifiers are currently under consideration. In addition, currently, integrated optical filters are waveguide type filters integrated on a substrate, and optical filters that control the transmission wavelength within the etalon surface by partially changing the refractive index of the etalon. Being developed.

[0004]

In the conventional optical switch, when a large-scale switch is constructed by these components shown in FIG. 43, there is concern about the reliability of components such as a birefringent plate and component accuracy. Assembling accuracy is highly required, and there is a defect that causes a reduction in yield in actual manufacturing.

Further, in the conventional optical amplifier, at least one pumping light source and usually two optical isolators are used for one input / output optical fiber amplifier, so that the number of optical amplifiers per input / output line is increased. There was a problem of high cost, which hindered the popularization of optical amplifiers. Further, in the semiconductor optical amplifier, there is a problem that the amplification factor largely varies depending on the input polarization, and the pattern effect is produced due to the influence of the electron relaxation time.

On the other hand, in the integration of the optical filter,
If the transmission wavelength of the filter is changed by controlling the temperature or voltage at a specific point in the two-dimensional plane and, for example, if the transmission wavelength of the filter is at regular intervals, measure the transmission wavelength of each filter, or It is necessary to monitor the control elements such as temperature and voltage at each control point at each point, which causes a problem of complicated control.

It is an object of the present invention to provide an optical switch that does not cause a reduction in yield during manufacturing and an optical device equipped with the optical switch. Another object of the present invention is to provide an optical filter capable of performing simple temperature control and voltage control, and an optical device equipped with the optical filter. Another object of the present invention is to provide an inexpensive optical amplifier and an optical device equipped with the optical amplifier.

[0008]

[Means for Solving the Problems]

(1) Configuration of First Invention The basic configuration and driving method of the optical switch according to the first invention will be described below. FIG. 1 is a diagram showing a basic configuration of an optical switch according to the first invention. In FIG. 1, 1 is a polarization plane rotating element, 2 is a polarization separation film, 3 is an optical input A, 4 is an optical input B, 5 is an optical output C, and 6 is an optical output D. Optical input 3,4
Is input with P polarization (the vibration direction of the electric field is parallel to the paper surface).

FIG. 2 is a diagram showing the operation of the optical switch according to the first aspect of the invention. The polarization plane rotating element realized by a liquid crystal, a Faraday rotator or the like is shown in FIG. 2 when the polarization plane of the transmitted light is not rotated. The cross state is set as shown in (a), and the bar state is set as shown in FIG. 2 (b) when the polarization plane of the incident light is rotated by 90 degrees by the polarization plane rotating element. The optical outputs 5 and 6 are output with the same polarization as the incident light, regardless of the cross and bar states. Also, when the optical inputs 3 and 4 to the switch are S-polarized waves, a bar state occurs when the polarization plane rotation element cannot rotate the polarization, and the polarization plane rotation element rotates the polarization plane by 90 degrees. If you do, you will be in a crossed state. cross,
This switch is suitable for integration because the polarization state of the output light does not change at any bar setting.

In the optical switch according to the first aspect of the present invention, since the flat mirror, the flat polarization separation film, and the flat liquid crystal can be assembled while maintaining the parallel positional relationship, the parts can be manufactured easily and the assembling accuracy is also easy. Can be higher In addition, each switch element is equivalent to a conventional optical waveguide crossbar switch and is a waveguide type PI-LOSS switch (reference: T. Simoe, K.
Hajikano, and K. Murakami, "A path-independent ins
ertion loss opticalspace switching network ", in Te
ch. Dig. ISS'87, vol.4, Paper C12.2, 1987), the switching configuration is simple, and constant loss switching is possible regardless of the connected channel. (2) Configuration of the second invention In the optical fiber amplifier according to the second invention, in order to reduce the cost per input / output line of the optical fiber amplifier, which is required for a large number of input / output lines, a plurality of input / output lines are provided. The optical fiber amplifier uses a pumping light source common to a plurality of amplification media and an optical isolator common to a plurality of lines that collectively act on a plurality of parallel light beams. As a result, the cost of the optical fiber amplifier per I / O line can be reduced. (3) Configuration of the third invention In the optical filter according to the third invention, a plurality of optical filters whose wavelengths that are transmitted (or reflected or absorbed) are changed by a certain physical quantity P are used when a certain physical quantity changes one-dimensionally. By arranging in F, the wavelength to be filtered can be set regularly only by monitoring the physical quantity P or the filtered optical wavelength at both ends of the field F or at appropriate intervals. This facilitates control of the plurality of optical filters.

For example, if each optical filter is formed into a Fabry-Perot etalon and the temperature is used as the physical quantity P,
The change in transmission wavelength (Δλ) due to the temperature change (ΔT) can be expressed as follows. Δλ = (α + β) * λ * ΔT α: coefficient of linear expansion β: coefficient of change in refractive index normalized by refractive index with temperature λ: original transmission wavelength (reference: M. Ito, T. Kimura, IE
EE. J. of Quantum Electronics, VOL. QE-16, pp. 910-
911 (1980)) Thus, since the change of the transmission wavelength is expressed by the linear expression of the temperature change, if the optical filters are arranged at equal intervals in a rectangular parallelepiped having a uniform cross-sectional shape and a uniform material, the rectangular parallelepiped By controlling the temperature at both ends of the, it is possible to simultaneously control multiple optical filters arranged on a rectangular parallelepiped.

Specific values of α and β are as follows, when the Fabry-Perot etalon is made of AlGaAs compound.
= 0.6 × 10 ^-5 , β = 0.99 × 10 ^-4 , and Δλ = 0.8 nm when ΔT = 5 ° C for λ = 1550 nm (Reference: M. Ito, T. Kimura, IEEE. J. of Quantum Electroni
cs, VOL. QE-16, pp. 910-911 (1980)). For example, if each optical filter is in the form of a Fabry-Perot etalon and a voltage is used as the physical quantity P, the voltage change (Δ
The change (Δλ) in transmission wavelength due to V) is expressed as follows.

Δλ = γ * λ * ΔV γ: Coefficient of change in refractive index normalized by refractive index due to voltage λ: Original transmission wavelength Voltage distribution is such that resistors are arranged in series and a potential difference is provided at both ends. Then, the electrodes are placed between the resistors, and each of these electrodes is connected to one side of the optical filter to generate a potential difference between the electrodes, while the electrodes of the potential common to all the optical filters are connected. . By the above method, it is possible to apply a regularly changing voltage to each optical filter simply by changing the voltage across it, and it is possible to change the transmission wavelength regularly.

[0014]

【Example】

(1) First Invention FIG. 1 is a diagram showing a first basic configuration of an optical switch according to the first invention. Optical inputs 3 and 4 are input with P polarization (the vibration direction of the electric field is parallel to the paper surface). FIG. 2 is a diagram showing a light transmission state of the optical switch in the first invention. The figure (a) shows the transmission state of the light beam in the cross state, and the figure (b)
FIG. 6 is a diagram showing a light transmission state of a bar state. The polarization plane rotation element realized by liquid crystal or Faraday rotator is set to the cross state shown in Fig. 2 (a) when the polarization plane of the transmitted light is not rotated, and the polarization plane rotation element shifts the polarization of the incident light. Figure 2 (b) when the wavefront is set to rotate 90 degrees
The bar status is set as shown in. Optical outputs 5 and 6 are cross,
The same polarization as the incident light is output regardless of the bar state. When the optical inputs 3 and 4 to the switch are S-polarized, when the polarization plane rotation element cannot rotate the polarization, a bar state occurs, and when the polarization plane rotation element rotates the polarization plane by 90 degrees. It becomes a cross state.

FIG. 3 is a diagram showing a second basic structure of the optical switch in the first invention, showing an optical switch in the case of using a substance containing cholesteric liquid crystal instead of the polarization separation film. The helical pitch of the liquid crystal molecule system of the substance containing cholesteric liquid crystal is made almost equal to the wavelength of the input light, and effective selective reflection (one of the right-hand circular polarization and the left-hand circular polarization depending on the direction of the helix) It is set so that the wave component is transmitted and the other circularly polarized wave component is reflected).

FIG. 4 is a diagram showing an embodiment of a 4 × 4 PI-LOSS configuration switch. In FIG. 4, 9 is a mirror, 10 is a prism, 11 is input 0, 12 is input 1, 1
3 is input 2, 14 is input 3, 15 is output 0, 16 is output
1, 17 is output 2, 18 is output 3, 19 is refractive index about 1.5
, 20 is a sand surface that diffuses light. 16 in FIG.
It is a figure which shows the Example of the PI-LOSS structure switch of x16. In FIG. 5, 21 is a switch in which four 4 × 4 PI-LOSS switches are integrated in parallel, 22 is an optical path adjusting prism, 23 is an input ray train, and 24 is an output ray train.

(2) Second Invention FIGS. 6 to 11 are views showing first to sixth embodiments of an optical amplifier array according to the second invention, respectively. In each figure, 31 is an Er-doped optical fiber bundle, 32 is an excitation light source, 3
3 is a branching / multiplexing device, 34 is an optical isolator, 35 is an optical bandpass filter, 36 is a lens array, 37 is an arrayed ferrule, 38 is an input optical fiber bundle, and 39 is an output optical fiber bundle.

Further, FIG. 12 shows the branching used in FIGS.
It is a figure which shows the Example of a multiplexer (4 branch of pump light, and the multiplexing of pump light and signal light), the same figure (a) is a top view and the same figure (b) is a side view. In FIG. 12, 41 is a branching ND filter, 42 is a mirror, 43 is signal light, 44 is pump light, and 45 is signal light + pump light. 13 to 1
6 is a diagram showing a cross section of the optical amplifier array, in which the end face of the fiber is obliquely polished to reduce reflection. In the figure, 46 is a light beam, 47 is a sub-assembly (SA) by integrating a fiber and a collimating lens, and 48 is a support for spatially aligning the position and angle of SA.

FIG. 17 is a view showing the optical fiber end face aligning mechanism in FIG. 13 or FIG. 14, and shows an embodiment in which the end face is inclined to suppress reflection. FIG.
Is a front view, and FIG. 4B is a side view. (3) Third Invention FIG. 18 is a diagram showing a first embodiment of an optical filter according to the third invention. In the figure, 51 is a rigid body A, 52 is an optical filter, 53 is a lens, 54 is a ferrule, 55 is an optical fiber, 56 is an optical connector, 57 is a light beam, 58 is a thermal sensor,
Reference numeral 59 is a heating element, 60 is a temperature controller 1, 61 is a Peltier element, 62 is a temperature controller 2, 63 is a housing, and 64 is a radiation fin. The temperature is used as the physical quantity P, the rigid body A made of glass or the like is given a temperature distribution, and the temperature distribution is set using the heating elements, the temperature sensors, and the temperature controller arranged at both ends of the rigid body A. Each optical filter is made of an etalon material such as a semiconductor having a large refractive index change with temperature, and the transmission wavelength is set with regularity according to the temperature at each position of the rigid body A. In addition, the temperature of the housing of the optical filter is controlled by the temperature sensor, the Peltier element, and the temperature controller 2 arranged on the outer circumference of the housing.
The temperature is controlled to maintain a constant temperature so that the influence of the external environment can be eliminated.

FIG. 19 is a diagram showing a second embodiment of the optical filter according to the third invention. In addition to the control shown in FIG. 18, FIG. 19 shows a configuration in which a heating element and a temperature sensor, which are grounded every two optical filters, allow fine adjustment of the transmission wavelength of each optical filter. The fine adjustment of FIG. 19 is effective when it is necessary to consider the following things, for example.

Correction when the mounting position of the individual optical filter portion on the rigid body A is deviated and the temperature is different from the design temperature. Correction when the thermal conductivity of the rigid body A varies depending on the part and the set temperature of the individual optical filter becomes different from the design. As a method of correction (common), if the temperature measured by a thermal sensor installed at a location other than the ends of the rigid body A is lower than the design value, raise the temperature of the heating element placed close to this thermal sensor. To adjust. Conversely, if the temperature is higher than the set value, control is not performed.

FIG. 20 is a view showing a third embodiment (part) of the optical filter according to the third invention, and FIGS.
In the temperature gradient control type optical filter shown in Fig. 6, the connection with the rigid body A having a temperature gradient is performed through a support having a small cross-sectional area so that the temperature distribution inside each optical filter itself can be reduced. Is. FIG. 21 is a diagram showing a fourth embodiment (part) of the optical filter in the third invention, which is an embodiment of the optical filter using a voltage as the physical quantity P and an electric resistance as a field for generating the distribution. . The transmission wavelength is set to be different depending on the voltage applied to each optical filter.

FIG. 22 is a diagram showing a fifth embodiment of the optical filter according to the third invention, which is an example of the configuration for monitoring the wavelengths at both ends in controlling the optical filter shown in FIG. Figure 2
The wavelength 2 monitor monitors the reference light quantity by converting the light quantity when the light of the reference wavelength is input to the reference optical filter into an electric signal by the wavelength monitor consisting of a photodiode and an electric circuit. It is stored in memory, and when the optical filter is used, the amount of light input to the wavelength monitor is electrically converted and compared with the reference value, and temperature control is performed so that the value at that time is within a certain range of deviation from the reference value. . As for the control method, if the wavelengths of the optical filters at both ends of the optical filter array are controlled, the wavelengths of the optical filters between them can be controlled. (4) Fourth invention (configuration example of polarization independence of optical switch) FIG. 23 is a diagram showing an embodiment in which the polarization dependency of an input optical signal is almost eliminated, and (a) to (c). 3 types are shown. It is separated into two polarization components orthogonal to each other by the polarization separator in the input section, and one of the spatially separated polarization components is
Approximately 9 polarization planes using a λ / 2 plate or Faraday rotator
The optical signal is sent to the main part of the optical switch by rotating it by 0 degree and matching it with the other polarization split by the polarization splitter and making it into two rays that are parallel to each other. At the main part of the optical switch, the switch is set by one of the following three methods.

Two switches each having a normal configuration are arranged in parallel to set the switches. The two switch elements arranged side by side perform the same operation at the same time to set the switch. Two rays are input to one switch element to set the switch. After passing through the switch body, one of the two parallel rays is rotated by 90 degrees with a λ / 2 plate or a Faraday rotator to make it orthogonal to each other. The combiner outputs one beam and outputs it.

Incidentally, this type of polarization independent method is already known. However, it was only applied to this optical switch. (5) Fifth invention (combination method of optical switch, optical amplifier, optical filter, etc.) a) Embodiment of combination of optical switch and optical amplifier FIGS. 24 to 26 show an optical amplifier array and a spatial optical switch, respectively. It is a figure which shows the 1st-3rd Example used in combination. By using the arrayed optical amplifier in combination with the optical switch, it is possible to compensate for the loss when using the optical switch alone, and at a lower cost and in a smaller size than when using the optical switch and multiple individual optical amplifiers in combination. There is an advantage that the system can be realized. B) Example of combination of optical amplifier and optical filter FIG. 27 is a diagram showing an example of using an optical filter array and an optical amplifier array in combination. By using the optical filter and the optical amplifier in combination, the loss in the optical filter can be compensated. In addition, by using an arrayed optical filter and an arrayed optical amplifier in combination, this can be realized at a smaller size and at a lower cost than when using an individual optical filter and an individual optical amplifier. C) Embodiment of combination of optical filter and wavelength type switch FIG. 28 is a diagram showing a first embodiment using a combination of an optical filter array and a wavelength type optical switch. By using an arrayed optical filter in combination with a wavelength type switch, it is possible to achieve a smaller size than when using an individual optical filter and a wavelength type optical filter in combination.

FIG. 29 is a diagram showing a second embodiment in which an optical filter array and a wavelength type optical switch are used in combination. The arrayed optical filter is applied to the wavelength selective delay part of the wavelength type switch. It is an example. Also in this case, the size can be reduced as compared with the case where the individual optical filter is used. D) Example of Combination of Optical Filter and Spatial Optical Switch FIG. 30 is a diagram showing an example of using an optical filter array and a spatial optical switch in combination. By using an arrayed optical filter, a smaller size can be realized than using multiple individual optical filters. E) Example of combination of optical switch, optical amplifier and optical filter FIG. 31 is a diagram showing an example of using an optical filter array and a spatial optical switch in combination. By using an arrayed optical filter as the optical filter used for the input or output of the wavelength switch, rather than using multiple individual optical filters,
The size can be reduced. Also, by using an arrayed optical amplifier as the optical amplifier that compensates for the loss, the size can be reduced by using multiple individual optical amplifiers. There is also a high possibility of cost reduction. F) Example of combination of optical amplifier and transmission line FIG. 32 is a diagram showing an example of using an optical amplifier array and a transmission line in combination. When multiple transmission lines are arranged side by side, the optical amplifiers installed on the lines have the advantage that they can be realized at a smaller size and lower cost than using individual optical amplifiers. G) Embodiment of combination of optical amplifier and wavelength type switch FIGS. 33 and 34 are views showing first and second embodiments using a combination of an optical filter array and a wavelength type optical switch. By using arrayed optical amplifiers as optical amplifiers that compensate for the loss of wavelength-type switches, miniaturization can be achieved by using multiple individual optical amplifiers. There is also a high possibility of cost reduction. H) Example of combination of optical amplifier, optical filter and optical attenuator FIG. 35 is a diagram showing an example of using an optical amplifier array, an optical filter and an optical attenuator in combination. An amplifier has an amplification factor dependency depending on the wavelength. The wavelength band is divided into specific wavelength bands by an optical coupler and an optical filter array, and the attenuation factor is adjusted for each band. Has the advantage of being small. The use of arrayed optical amplifiers and arrayed optical filters has the advantage of miniaturization. I) Example of combination of optical amplifier and optical transmitter FIG. 36 is a diagram showing an example of using an optical amplifier and a plurality of optical transmitters in combination. One arrayed optical amplifier is used to deal with multiple transmitters, which has the advantage of cost reduction compared to using multiple individual optical amplifiers. N) Example of combination of optical amplifier and optical receiver FIG. 37 is a diagram showing an example of using an optical amplifier and a plurality of optical receivers in combination. One arrayed optical amplifier supports multiple receivers, which has the advantage of cost reduction compared to using multiple individual optical amplifiers. 38) Example of combination of optical amplifier and optical coupler FIG. 38 is a diagram showing an example of using an optical amplifier array and an optical coupler in combination. By amplifying after branching by the coupler, nonlinear effects in the optical fiber due to excessive optical input are suppressed, and by using arrayed optical amplifiers, it is more cost effective than using multiple individual optical amplifiers.
There is an advantage that it is possible to reduce the size and size. Wo) Example of combination of optical amplifier and photodetector FIG. 39 is a diagram showing an example of using an optical amplifier array and a plurality of photodetectors in combination. By using arrayed optical amplifiers as preamplifiers for multiple photodetectors, it is possible to reduce size and cost compared to using multiple individual optical amplifiers.
There is an advantage that can be achieved. W) Example of combination of optical amplifier and wavelength converter FIGS. 40 and 41 are diagrams showing first and second examples in which an optical amplifier array and a wavelength converter are used in combination. Since the optical amplifier has a limited wavelength band that can be amplified, in order to amplify the wavelength outside the amplifiable band of the optical amplifier, the wavelength is converted in front of the optical amplifier and is amplified to a wavelength within the amplifiable band. Therefore, it is necessary to perform wavelength conversion to the original wavelength again after amplification. The use of arrayed optical amplifiers as amplifiers for multiple wavelength converters has the advantage of cost reduction. F) Embodiment of combination of optical amplifier, demultiplexer, multiplexer and optical attenuator FIG. 42 shows an embodiment in which an optical amplifier array, an optical demultiplexer / optical multiplexer and an optical attenuator are used in combination. FIG. An amplifier has an amplification factor dependence on wavelength, and it has the advantage that the wavelength dependence of the overall amplification factor can be reduced by dividing the wavelength band and adjusting the attenuation factor for each band.

[0027]

As described above, according to the present invention, the following effects can be obtained. (1) Since the number of parts can be reduced, it is possible to prevent a decrease in yield that occurs during assembly. Further, by using the N input / N output N × N optical switch as a bypass switch, the line switching of various optical communication systems can be performed smoothly.

(2) It is possible to efficiently obtain light in a specific wavelength region in which the spectral distribution of incident light changes. (3) The temperature in the housing means can be controlled more uniformly. (4) By setting the wavelengths of the light passing through the mirror means to be different, it is possible to easily identify the light.

(5) The radiation cost can be increased. (6) Only the intensity of light can be increased while keeping the wavelength of light as it is. Moreover, since the number of components of the pumping light source and the optical isolator can be reduced, the manufacturing cost can be reduced. (7) An optical switch suitable as a switch for optical communication can be provided.

(8) An optical filter suitable as a filter for optical communication can be provided. (9) An optical amplifier suitable as an amplifier for optical communication can be provided. (10) The processing can be performed so as not to reduce the yield that occurs during assembly. In addition, it is possible to smoothly switch the lines of various optical communication systems.

(11) It is possible to increase only the light intensity while keeping the light wavelength. (12) Only the light intensity can be increased while keeping the light wavelength, and the number of treatments can be reduced, so that the treatment time and the cost required for the treatment can be reduced.

[Brief description of drawings]

FIG. 1 is a diagram showing a first basic configuration of an optical switch according to a first invention.

FIG. 2 is a diagram showing an operation of the optical switch according to the first invention.

FIG. 3 is a diagram showing a second basic configuration of the optical switch according to the first invention.

FIG. 4 is a diagram showing an embodiment of a 4 × 4 PI-LOSS configuration switch.

FIG. 5 is a diagram showing an embodiment of a 16 × 16 PI-LOSS configuration switch.

FIG. 6 is a diagram showing a first embodiment of an optical amplifier array according to the second invention.

FIG. 7 is a diagram showing a second embodiment of the optical amplifier array according to the second invention.

FIG. 8 is a diagram showing a third embodiment of the optical amplifier array according to the second invention.

FIG. 9 is a diagram showing a fourth embodiment of the optical amplifier array according to the second invention.

FIG. 10 is a diagram showing a fifth embodiment of the optical amplifier array according to the second invention.

FIG. 11 is a diagram showing a sixth embodiment of the optical amplifier array according to the second invention.

FIG. 12 is a diagram showing an embodiment of the branching / multiplexing device in FIGS. 6 to 8;

13 is a diagram showing a cross section of the first optical fiber amplifier array in FIG. 6 or FIG.

14 is a view showing a cross section of the second optical fiber amplifier array in FIG. 6 or FIG.

FIG. 15 is a diagram showing a cross section of a third optical fiber amplifier array.

FIG. 16 is a diagram showing a cross section of a fourth optical fiber amplifier array.

17 is a view showing the optical fiber end face alignment mechanism in FIG. 13 or FIG.

FIG. 18 is a diagram showing a first embodiment of an optical filter according to the third invention.

FIG. 19 is a diagram showing a second embodiment of the optical filter according to the third invention.

FIG. 20 is a diagram showing a third embodiment (part) of the optical filter according to the third invention.

FIG. 21 is a view showing a fourth embodiment (part) of the optical filter according to the third invention.

FIG. 22 is a diagram showing a fifth embodiment of the optical filter according to the third invention.

FIG. 23 is a diagram showing an example in which the polarization dependence of the input optical signal is almost eliminated.

FIG. 24 is a diagram showing a first embodiment using a combination of an optical amplifier array and a spatial optical switch.

FIG. 25 is a diagram showing a second embodiment using a combination of an optical amplifier array and a spatial optical switch.

FIG. 26 is a diagram showing a third embodiment using a combination of an optical amplifier array and a spatial optical switch.

FIG. 27 is a diagram showing an example in which an optical filter array and an optical amplifier array are used in combination.

FIG. 28 is a diagram showing a first embodiment using a combination of an optical filter array and a wavelength type optical switch.

FIG. 29 is a diagram showing a second embodiment using a combination of an optical filter array and a wavelength type optical switch.

FIG. 30 is a diagram showing an embodiment in which an optical filter array and a spatial optical switch are used in combination.

FIG. 31 is a diagram showing an example in which an optical filter array and a spatial optical switch are used in combination.

FIG. 32 is a diagram showing an embodiment in which an optical amplifier array and a transmission line are used in combination.

FIG. 33 is a diagram showing a first embodiment using a combination of an optical filter array and a wavelength type optical switch.

FIG. 34 is a diagram showing a second embodiment using a combination of an optical filter array and a wavelength type optical switch.

FIG. 35 is a diagram showing a first embodiment using a combination of an optical amplifier array, an optical filter, and an optical attenuator.

FIG. 36 is a diagram showing an embodiment in which an optical amplifier and a plurality of optical transmitters are used in combination.

FIG. 37 is a diagram showing an embodiment in which an optical amplifier and a plurality of optical receivers are used in combination.

FIG. 38 is a diagram showing an embodiment in which an optical amplifier array and an optical coupler are used in combination.

FIG. 39 is a diagram showing an embodiment in which an optical amplifier array and a plurality of photodetectors are used in combination.

FIG. 40 is a diagram showing a first embodiment using a combination of an optical amplifier array and a wavelength converter.

FIG. 41 is a diagram showing a second embodiment using a combination of an optical amplifier array and a wavelength converter.

FIG. 42 is a diagram showing an embodiment in which an optical amplifier array, an optical demultiplexer / optical multiplexer, and an optical attenuator are used in combination.

FIG. 43 is a diagram showing an optical switch using conventional polarization control.

FIG. 44 is a diagram showing a conventional optical fiber amplifier.

[Explanation of reference symbols] 1: Polarization plane rotating element 2: Polarization separation film 3: Optical input A 4: Optical input B 5: Optical output C 6: Optical output D 7: Substance containing cholesteric liquid crystal 8: λ / 4 plate 9: Mirror 10: Prism 11: Input 0 12: Input 1 13: Input 2 14: Input 3 15: Output 0 16: Output 1 17: Output 2 18: Output 3 19: Material with a refractive index of about 1.5 20: Light Sand surface to diffuse 21: 4 x 4 PI-LOSS Switch with 4 switches integrated in parallel 22: Optical path adjusting prism 23: Input beam train 24: Output beam train 31: Er-doped optical fiber bundle 32: Excitation light source 33 : Branching / multiplexing device 34: Optical isolator 35: Optical bandpass filter 36: Lens array 37: Arrayed ferrule 38: Input optical fiber bundle 39: Output optical fiber bundle 40: Multiplexing filter 41: Branching ND filter 42: Mirror 43 : Signal light 44: Pump light 45: Signal light + Pump light 51: Rigid body A 52: Optical filter 53: Lens 54: Ferrule 55: Optical fiber 56: Optical connector 57: Ray 58: Thermal sensor 59: Heating element 60: Temperature controller 1 61: Peltier element 62: Temperature controller 2 63: Housing 64: Radiating fin 65: Support 66: Substance having electro-optical effect 67: Resistor 68: Transparent electrode 69: Voltage V ₀ 70: Voltage V ₁ 71: Voltage V ₂ 72: Wavelength monitor

Claims (27)

[Claims] 1. An optical input port and an optical output port are provided,
When the light beams that make up the crossbar switch are in the cross state, the settings are such that they pass through the polarization plane rotator with a variable rotation angle, the polarization separation film, and the polarization plane rotator with a variable rotation angle. When the constituent rays are in the bar state, they pass through the polarization plane rotation element with a variable rotation angle, are reflected by the polarization separation film, and pass through the polarization plane rotation element with a variable rotation angle. Characteristic optical switch. 2. An optical input port and an optical output port are provided,
When the light rays that make up the crossbar switch are in the crossed state, the polarization plane rotation element that has a variable rotation angle, a substance that exhibits reflective properties that are selective to the left and right circularly polarized waves, such as cholesteric liquid crystal, and the rotation angle is It is set to pass through the variable polarization plane rotation element, and when the light beam forming the crossbar switch is in the bar state, it passes through the variable polarization plane rotation element and is reflected by the cholesteric liquid crystal. The optical switch is characterized in that the setting is such that it passes through a polarization plane rotating element with variable. 3. The optical switch according to claim 1, wherein the optical switch has a plurality of optical input ports and a plurality of optical output ports. 4. The optical switch according to claim 3, wherein a prism for an input / output port, two or more parallel mirrors for changing an optical path, and a plurality of polarization plane rotating elements are integrated in the same plane. An optical switch characterized by using a plate-shaped structure. 5. The optical switch according to claim 3, wherein the optical switch has a PI-LOSS configuration. 6. The optical switch according to claim 2, wherein cholesteric liquid crystal is used. 7. An optical fiber which constitutes an inversion distribution of N natural numbers of 2 or more, serves as an amplification medium, a number of pumping light sources less than N, optical isolators less than 2 × N, an optical coupling system, and a multiplexer. An optical fiber amplifier of N input and N output, comprising: 8. An optical fiber which constitutes an inversion distribution of N natural numbers of 2 or more, serves as an amplification medium, a pumping light source of a number less than N, two optical isolators, an optical coupling system, a multiplexer, and an optical band. N comprising a pass filter and
Input N output optical fiber amplifier. 9. A natural number N input optical fibers of 2 or more, N
For parallel fiber end face alignment mechanism, N spatially arranged lenses, 1 optical isolator working for N rays, N input rays and less than N pumping sources A branching / combining device that acts against each other to couple the pumping light to subsequent N fibers serving as amplification media, N parallel fiber end face alignment mechanisms, N amplification media fibers, and N parallel fibers. Fiber end face alignment mechanism, N spatially arranged lenses in parallel, one optical isolator that works for N rays, an optical bandpass filter that works for N rays, N An optical fiber characterized in that lenses arranged spatially in parallel, N parallel fiber end face alignment mechanisms, and N output optical fibers are arranged in the above order, and further less than N pumping light sources are provided. Amplifier. 10. A natural number N input optical fibers of 2 or more,
N parallel fiber end face alignment mechanisms, N spatially arranged lenses, one optical isolator working on N rays, N parallel fiber end face alignment features, N A fiber serving as an amplification medium, N parallel fiber end face alignment mechanisms, N spatially arranged lenses in parallel, acting on N input light beams and less than N pump light sources to generate pump light. A branching / multiplexing device that is coupled to the fiber serving as the N amplification medium in the front, one optical isolator that functions for N rays, an optical bandpass filter that functions for N rays, N Of the optical system, wherein the spatially parallel lenses, the N parallel fiber end face aligning mechanisms, and the N output optical fibers are arranged in the above order, and further less than N pumping light sources are provided. Fiber amplifier. 11. A natural number N input optical fibers of 2 or more,
N parallel fiber end face alignment mechanisms, N spatially arranged lenses, 1 optical isolator working on N rays, N input rays and less than N pumping sources For coupling the pumping light to subsequent N fibers serving as amplification media, N parallel fiber end face alignment mechanisms, N amplification fibers, and N amplification media. Parallel fiber end face alignment mechanism, N spatially arranged lenses in parallel, act on N input rays and less than N pump sources to direct pump light to the front N
Branching / multiplexing device that is coupled to the fiber that serves as the amplification medium, one optical isolator that functions for N rays, an optical bandpass filter that functions for N rays, and N spatial points An optical fiber amplifier characterized by arranging lenses arranged in parallel with each other, N parallel fiber end face alignment mechanisms, and N output optical fibers in the above order, and further providing less than N pumping light sources. 12. A natural number N input optical fibers of 2 or more,
N parallel fiber end face alignment mechanisms, N spatially arranged lenses, one optical isolator working on N rays, N parallel fiber end face alignment features, N A splitter / combiner that acts on the input light beam and less than N pumping light sources to couple the pumping light to the subsequent N fibers serving as amplification media, N fibers serving as amplification media, and N fibers Parallel fiber end face alignment mechanism, N spatially arranged lenses, 1 optical isolator that works for N rays, N optical bandpass filter that works for N rays Spatially parallel lenses, N parallel fiber end face alignment mechanisms, N
An optical fiber amplifier, characterized in that a plurality of output optical fibers are arranged in the above order, and further less than N pumping light sources are provided. 13. A natural number N input optical fibers of 2 or more,
N parallel fiber end face alignment mechanisms, N spatially arranged lenses, one optical isolator working on N rays, N parallel fiber end face alignment features, N A fiber serving as an amplification medium, a branching beam which acts on N input light beams and less than N pumping light sources to couple the pumping light to N forward fibers serving as an amplification medium.
Multiplexer, N parallel fiber end face alignment mechanisms, N spatially aligned lenses, 1 optical isolator that works on N rays, works on N rays An optical bandpass filter, N spatially arranged lenses in parallel, N parallel fiber end face alignment mechanisms, N output optical fibers are arranged in the above order, and a pumping light source less than N is provided. An optical fiber amplifier characterized by that. 14. A natural number N input optical fibers of 2 or more,
N parallel fiber end face alignment mechanisms, N spatially arranged lenses, one optical isolator working on N rays, N parallel fiber end face alignment features, N A splitter / combiner that acts on an input beam and less than N pumping light sources to couple the pumping light to the subsequent N fibers serving as amplification media, N fibers serving as amplification media, and N fibers A splitter / multiplexer that acts on an input light beam and less than N pumping light sources to couple the pumping light to N forward fibers serving as an amplification medium, N parallel fiber end face alignment mechanisms, N , Spatially arranged in parallel, one optical isolator that works for N rays, an optical bandpass filter that works for N rays, N spatially arranged lenses , N parallel fiber end face aligners , An optical fiber amplifier characterized in that arranged N output optical fiber, the order of above, provided even less pumping source than the N. 15. An optical fiber amplifier according to claims 9 to 14, wherein a fiber and a collimating lens are integrated to form a sub-assembly (SA) instead of the fiber end face alignment mechanism and the spatially arranged lens. The optical fiber amplifier is characterized in that a plurality of SAs are integrated with a support for spatially aligning the positions and angles of the SAs. 16. The optical fiber amplifier according to claim 7, wherein the fiber end face aligning mechanism in which fibers are arranged two-dimensionally is obliquely polished for each column (or row) when the fiber end face aligning mechanism is used. An optical fiber amplifier characterized by using. 17. A field F in which a certain physical quantity P is spatially distributed.
An optical filter characterized by arranging a plurality of optical filters and controlling the characteristics of these optical filters by adjusting the distribution of the physical quantity P of the field F. 18. A field F in which a certain physical quantity P is one-dimensionally distributed.
An optical filter characterized by arranging a plurality of optical filters and controlling the characteristics of these optical filters by adjusting the distribution of the physical quantity P of the field F. 19. A field F in which a certain physical quantity P is one-dimensionally distributed.
, A plurality of optical filters in a plurality of columns are arranged in parallel in the direction in which the physical quantity changes, and the characteristics of these optical filters are controlled by adjusting the distribution of the physical quantity P of the field F. filter. 20. An optical filter characterized in that a plurality of optical filters are arranged on an object A having a temperature distribution, and the characteristics of these optical filters are controlled by adjusting the temperature distribution of A. 21. An optical filter characterized in that a plurality of optical filters are arranged on an object A having a temperature distribution in one direction, and the characteristics of these optical filters are controlled by adjusting the temperature distribution of A. . 22. The optical filter according to claim 17, wherein each optical filter is a filter having a characteristic of an etalon structure. 23. The optical filter according to claim 17, wherein the temperature distribution of the object A (or field F) having a temperature distribution is controlled by using a resistance and a heat sensor. . 24. The optical filter according to any one of claims 17 to 19, wherein an electric field is used as the physical quantity P. 25. The optical filter according to any one of claims 17 to 19, wherein a magnetic field is used as the physical quantity P. 26. The optical filter according to claim 17, wherein pressure is used as the physical quantity P. 27. The optical filter according to any one of claims 24 to 26, wherein the optical filter having an etalon structure is used.