JP3156228B2 - Light control type optical switch and control method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to optical communication, optical information processing,
The present invention relates to a light control type optical switch which can be used for an optical wiring of an electronic device or the like, or an optical drive type micro machine expected to be used in a medical device or the like, and a control method thereof.

[0002]

2. Description of the Related Art As conventional optical switches, three methods shown in FIGS. 16 to 18 are known according to their control methods.

The first is a method of mechanically switching the light path as shown in FIG.

In FIG. 16, reference numeral 11 denotes an optical waveguide or an optical fiber on the incident side, 12 denotes an optical waveguide or an optical fiber on the output side, and an optical fiber on the incident side at a branch point 13 as shown in FIG. The light is mechanically moved to switch light to one of the emission sides.

[0005] Second, as shown in FIG. 17, the optical path is switched by changing the refractive index of the branch point of the light guide path electrically or by light irradiation.

In FIG. 17, reference numeral 11 denotes an optical waveguide or optical fiber on the incident side, 12 denotes an optical waveguide or optical fiber on the output side, 105 denotes an electrode, and a branch point 13 of the light guide, that is, an intersection of the light guide 14. Alternatively, the optical path is switched by electrically changing the refractive index of the proximity portion.

In FIG. 17, instead of electrically changing the refractive index 13 at the branch point of the light guide path, the optical path is switched by changing the refractive index of the branch point 13 of the light guide path by irradiation with control light. It is also possible to do.

Third, as shown in FIG. 18, the incident light is diffracted by the acousto-optic effect of the surface acoustic wave to switch the optical path.

In FIG. 18, reference numeral 110 denotes incident guided light, 1
11, diffracted light, 112, transmitted light, 113, surface acoustic wave,
Reference numeral 114 denotes a power supply, and reference numeral 115 denotes a comb-shaped electrode that generates a surface acoustic wave. The comb-shaped electrode 115 diffracts the incident guided light 110 by the acousto-optic effect of the surface acoustic wave 113 and switches the optical path in the direction of 111.

[0010] In FIG.
Is light propagating in space without using an optical waveguide (hereinafter, referred to as
It is called propagating light. ).

[0011]

What is common to all of the above conventional optical switches is that the optical path is switched by changing the state of the branch point by means independent of the guided light or the propagated light. is there.

In FIG. 17, even when the refractive index of the branch point 13 of the light guide path is changed by the control light, the switching is still performed by the independent control light.

As a result, it is necessary to provide wiring and optical components for controlling the optical switch. In particular, when a large number of branch points are arranged in multiple stages, the wiring occupies a space. was there.

In particular, the development of a light actuator driven by light (or the thermal action of light), which is expected to put a micromachine as a medical device into practical use in the future, has been actively pursued. However, there is a problem that the cooperative movement of a large number of fine drive elements is indispensable, and if this is performed by a conventional optical switch, the wiring becomes enormous and the advantage of the micro machine is impaired.

Further, there is a demand that the living body does not want to use electricity. For this reason, if a conventional light control optical switch is used, a larger optical wiring space is required than the electric wiring. .

In this case, if the optical interconnection for propagating light is used, the above problem does not occur. However, it is not practical when the connection destination of the light moves or when it can be used only in a narrow space.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem, and an object of the present invention is to provide a light control type light which determines its own path by guided light or propagated light itself. It is to provide a technology that enables a switch.

The above and other objects and novel constitutions of the present invention will be apparent from the description of the present specification and the accompanying drawings.

[0019]

In order to achieve the above object, a first aspect of the present invention is a light control type optical switch, comprising: a wavelength filter that transmits only light of a specific wavelength; An optical shutter comprising a combination with a shape memory alloy whose shape is changed by light irradiation, which is arranged on the opposite side of the surface to which light is irradiated of the filter, is inserted at a branch point in the optical waveguide path. And

The means (2) of the present invention is a light control type optical switch, comprising: a wavelength filter that transmits only light of a specific wavelength; An optical shutter arranged in combination with a magnetic phase change alloy that becomes ferromagnetic by light irradiation,
A magnet inserted at a branch point in the optical waveguide path and for moving the magnetic phase change alloy that has become ferromagnetic is arranged near the magnetic phase change alloy. .

[0021] The means (3) of the present invention is a light control type light switch comprising at least two light control type optical switches comprising the means (1) or (2) in the same optical waveguide path. In the optical switch, a transmission wavelength of the wavelength filter is different for each of the light control type optical switches.

Further, the means (4) of the present invention is directed to a light control type switch having at least two light control type optical switches comprising the means (1) or (2) in the same optical waveguide path. The optical switch is characterized in that the shape change temperature of the shape memory alloy or the phase change temperature of the magnetic phase change alloy is different for each of the light control type optical switches.

Further, the means (5) of the present invention is directed to a light for causing a guided operation or a propagating light to enter the light control type optical switch of any of the above-mentioned means (1) to (4) to perform a switch operation. A control method of a control-type optical switch, wherein a switch operation is performed according to a wavelength of the guided light or the propagated light or an incident time.

[0024]

FIGS. 1 and 2 are schematic views for explaining the operation principle of the light control type optical switch of the present invention.

1 and 2, reference numeral 1 denotes a guided light, 11A
11E, 12A to 12D are optical fibers or optical waveguides, 13A to 13D are branch points, and 15 is an optical shutter which is deformed or moved by light irradiation.

In FIGS. 1 and 2, since the branch points are formed in multiple stages (branch points 13A to 13D), the optical fibers or optical waveguides 11A to 11E on the exit side of the branch points are
It is an optical fiber or optical waveguide on the incident side of the next branch point.

As shown in FIGS. 1 and 2, the light control type optical switch of the present invention is an optical shutter 1 which is inserted into branch points 13A to 13D and which is deformed or moved by light irradiation.
By irradiating the waveguide 5 with the guided light 1 and deforming or moving the optical shutter 15, the path of the guided light 1 can be changed.

FIG. 1 shows a state in which all of the branch points 13A to 13D are closed and the guided light 1 propagates along the main path. FIG. 2 shows a state in which the branch point 13B is opened and the branching light exits therefrom. The state where the guided light 1 is propagating in the optical fiber or the optical waveguide 12B is shown.

That is, according to the above-described means, the optical shutter inserted at the branch point is deformed or moved by changing the wavelength of the guided light or the propagating light itself or by performing pulse modulation. An optical control type optical switch that determines a path can be realized.

[0030]

Embodiments of the present invention will be described below in detail with reference to the drawings.

In all the drawings for explaining the embodiments, parts having the same functions are given the same reference numerals and their repeated explanation is omitted.

[Embodiment 1] FIGS. 3 and 4 are diagrams showing a schematic configuration of a light control type optical switch which is Embodiment 1 of the present invention.

3 and 4, reference numeral 1 denotes a guided light, 11
A, 11B and 12 are optical waveguides or optical fibers;
Is a shape memory alloy, and 36 is an optical bandpass filter that allows light of only a specific wavelength to pass.

In the first embodiment, the optical shutter 15 shown in FIGS. 1 and 2 is a combination of a shape memory alloy 35 and an optical bandpass filter 36 that allows light of a specific wavelength to pass.

FIG. 3 shows that the wavelength of the guided light 1 is different from the transmission region of the optical bandpass filter 36 and the shape memory alloy 35
2 shows a state in which the optical shutter composed of a combination of the optical bandpass filter 36 and the optical bandpass filter 36 is closed, and a state in which the guided light 1 is reflected by the optical bandpass filter 36 and propagates to the optical waveguide or the optical fiber 11B. .

[0036] When the wavelength of the guided wave 1 matches the transmission area of the optical band-pass filter 36, guided light 1, light band
After passing through the pass filter 36 , the shape memory alloy 35 is irradiated, and the shape memory alloy 35 is heated.

The shape memory alloy 35 is deformed at a certain temperature or higher to make the guided light 1 go straight.

FIG. 4 shows that the shape memory alloy 35 is deformed, the optical shutter composed of the combination of the shape memory alloy 35 and the optical band-pass filter 36 is opened, and the guided light 1 goes straight to the optical waveguide or the optical fiber 12. This shows a state of propagation.

In the first embodiment, a tunable laser whose wavelength can be varied is used as a light source of the guided light 1.
If the passing wavelength region of the optical bandpass filter 36 at each of the branch points 13A to 13D shown in FIGS. 1 and 2 is set so as not to cause crosstalk, each of the branch points 13A to 13D shown in FIGS. In the above, only light having a wavelength that matches the transmission wavelength region can deform the shape memory alloy 35 at each of the branch points 13A to 13D. Therefore, by changing the wavelength of the guided light 1, It is possible to change the path of the guided light 1.

[Embodiment 2] FIGS. 5 and 6 are diagrams showing a schematic configuration of a light control type optical switch which is Embodiment 2 of the present invention.

As in the first embodiment, the second embodiment uses a shape memory alloy as the optical shutter 15 shown in FIGS.

5 and 6, reference numeral 11 denotes an optical waveguide, 5
1 is an optical waveguide substrate, 35 is a shape memory alloy, 52 is a fixing point of the shape memory alloy 35, 53 is a glass substrate holding the shape memory alloy 35, and 54 is a hole formed in the glass substrate 53.

The optical waveguide 11 is made of quartz and doped with Ge to reduce the relative refractive index difference from the cladding by 0.3.
The optical waveguide 11 bent in the shape of a "ku" having a core of% was formed.

This is changed to the optical waveguide 11 at the bending point 56.
Then, the entire substrate was polished perpendicularly to the shape shown in FIG.

The optical waveguide 11 has a core shape of 8 μm × 8
It is a single-mode optical waveguide for semiconductor laser light having a wavelength of 1.3 μm and a rectangular shape of μm.

As the shape memory alloy 35, an alloy of 50% of Ni and 50% of Ti having a thickness of 3 μm was formed on a glass substrate by sputtering, shaped into a square of 20 μm, and separated from the substrate.

This was annealed in a vacuum at 600 ° C. for 6 hours in an electric furnace.

At the time of annealing, the NiTi film was wound around a quartz glass rod.
Curled according to the curvature of the glass rod.

As shown in FIG. 6, this was fixed at one end only to a glass substrate 53 and attached near a hole 54 of the glass substrate 53.

The curl of the shape memory alloy 35 was corrected by attaching it to the optical waveguide 11 with an adhesive tape having a weak adhesive force at the tip.

A matching liquid was inserted between the optical waveguide 11 and the shape memory alloy 35 to suppress light scattering.

In the second embodiment, no optical bandpass filter is inserted between the shape memory alloy 35 and the end of the optical waveguide 11.

In the second embodiment, the guided light 1 is
In the above, a state in which the shape memory alloy 35 is all irradiated was applied, and a 1.3 μm wavelength semiconductor laser beam was introduced from the incident end of the optical waveguide 11.

When the power is initially low, there is no change in the shape memory alloy 35, and the guided light 1 is reflected by the shape memory alloy 35 and the light propagates to the optical waveguide 11 on the emission side.

[0055] was the incident power to 60 mW, the shape memory alloy 35 undergoes a deformation, striking the adhesive strength of the adhesive tape
Chi win curling deformation force is generated occurs, the shape memory alloy 35 leaves the optical waveguide 11.

As a result, light was emitted from the core in the direction of 22.

After the measurement, the martensitic transformation temperature of the shape memory alloy 35 was 40 ° C.

In the second embodiment, a quartz-based material is used as the material of the optical waveguide 11, but the material is not necessarily limited to this.

As the shape memory alloy 35, NiTi
Although an alloy was used, it is not necessarily limited to this.

In the second embodiment, the shape change temperature of the shape memory alloy 35 at each of the branch points 13A to 13D shown in FIGS. 1 and 2 is made different, and the irradiation time of the guided light 1 is changed. , Each branch point 13A to 13D
Since the deformation of the shape memory alloy 35 can be controlled, it is possible to change the path of the guided light 1 by the guided light 1 itself by changing the irradiation time of the guided light 1.

Third Embodiment FIGS. 7 and 8 are diagrams showing a schematic configuration of a light control type optical switch according to a third embodiment of the present invention.

In FIGS. 7 and 8, reference numeral 1 denotes a guided light;
A, 11B and 12 are optical waveguides or optical fibers;
Is an optical bandpass filter that allows light of only a specific wavelength to pass, 71 is a magnetic phase change alloy, and 72 is a magnet.

As the magnetic phase change alloy 71, for example, F
An eRh magnetic phase change alloy is used.

In the first embodiment, the optical shutter 15 shown in FIGS. 1 and 2 is a combination of the magnetic phase change alloy 71, the magnet 72, and the optical band-pass filter 36 that allows light of a specific wavelength to pass. .

[0065] FIG. 5, like FIG. 3, the wavelength of the guided wave 1 is, unlike the transmission region of the optical band-pass filter 36, an optical shutter consisting of a magnetic phase change alloy 71, the magnet 72 and the optical band-pass filter 36 Indicates a closed state, and indicates a state in which the guided light 1 is reflected by the optical bandpass filter 36 and propagates to the optical waveguide or the optical fiber 11B.

If the wavelength of the guided light 1 is an optical bandpass filter
-36 , the guided light 1 is in the optical band.
The magnetic phase change alloy 71 is irradiated by passing through the pass filter 36 to heat the magnetic phase change alloy 71.

The magnetic phase change alloy 71 causes a ferromagnetic phase change from a certain temperature.

The magnetic phase change alloy 71 is diamagnetic at room temperature and is not attracted to the magnet 72, but when it becomes ferromagnetic, it is attracted to the magnet 72 and causes the guided light 1 to travel straight.

FIG. 6 shows a state in which the optical shutter including the magnetic phase change alloy 71, the magnet 72 and the optical bandpass filter 36 is opened, and the guided light 1 travels straight and propagates to the optical waveguide or the optical fiber 12. ing.

In the third embodiment, the magnetic phase change alloy 7
Although the FeRh magnetic phase change alloy was used as No. 1, it is not necessarily limited to this.

In the third embodiment, a tunable laser whose wavelength can be varied is used as a light source of the guided light 1.
If the passing wavelength region of the optical bandpass filter 36 at each of the branch points 13A to 13D shown in FIGS. 1 and 2 is set so as not to cause crosstalk, each of the branch points 13A to 13D shown in FIGS. In the above, only light having a wavelength matching the transmission wavelength region can change the magnetic phase change alloy 71 at each of the branch points 13A to 13D to ferromagnetic phase change. The wave light 1 itself can change the path of the guided light 1.

[Embodiment 4] FIGS. 9 and 10 are diagrams showing a schematic configuration of a light control type optical switch which is Embodiment 4 of the present invention.

9 and 10, reference numeral 1 denotes a guided light, 11
A, 11B and 12 are optical waveguides or optical fibers;
Denotes a magnetic phase change alloy, 72 denotes a magnet, and 91 denotes a dielectric thin film coated on the surface of the magnetic phase change alloy 71.

As the magnetic phase change alloy 71, for example, F
eRh magnetic phase change alloy or FeRh with Pd, P
An FeRh magnetic phase change alloy to which elements such as t and Ir are added is used.

The dielectric thin film 91 coated on the surface of the magnetic phase change alloy 71 has a different light absorption coefficient at a certain wavelength.

In the fourth embodiment, the optical shutter 15 shown in FIGS. 1 and 2 is a combination of a magnetic phase-change alloy 71 having a surface coated with a dielectric thin film 91 and a magnet 72.

FIG. 11 shows the temperature change of the magnetization of the FeRh magnetic phase change alloy.

In the case of 50% Fe and 50% Rh, FIG.
As shown in FIG. 1, at the temperature T2, the phase changes from antiferromagnetic to ferromagnetic,
Thereafter, as the temperature rises, the magnetization decreases according to Curie-Weiss' law, and becomes paramagnetic at the Curie point, and the magnetization disappears.

T1 is a temperature around 80 ° C.

On the other hand, when elements such as Pd, Pt, and Ir are added to FeRh, the transition temperature between antiferromagnetic and ferromagnetic changes,
In the case of Pd, it is lower than T1, and in the case of Pt and Ir, it is higher than T1.

FIG. 12 shows a temperature rise with respect to heating energy when a dielectric film is coated on the surface of the FeRh magnetic phase change alloy and the light absorption coefficient is changed.

(A) is a case where the absorption coefficient is large, and the temperature rise is steep with respect to the heating energy.
(B) According to (c), the absorption coefficient decreases and the temperature rise decreases.

FIG. 13 is a graph showing Fe at each transition temperature shown in FIG.
In the case where a dielectric film is coated on the surface of the Rh alloy and the transition temperature is low for light of a certain wavelength, the absorption coefficient becomes higher and the absorption coefficient becomes lower as the transition temperature becomes higher. It shows a temperature change with respect to the heating energy of light.

In FIG. 13, the lower the transition temperature, the greater the temperature rise with the same energy, so that the transition occurs earlier and the Curie point is reached earlier.

In the fourth embodiment, the magnetic phase change alloy 71 having the characteristics shown in FIG. 13 is used as the magnetic phase change alloy 71 of the optical shutter 15 at each of the branch points 13A to 13D shown in FIGS. Used.

When it is desired to open a shutter using the magnetic phase change alloy 71 having a transition energy of E1 (hereinafter referred to as E1) as a component, the heating energies are set to E1 and E1.
The pulse width of the guided light 1 is determined, or the number of pulses having the same pulse width is determined so that the pulse width can be set between the two.

As a result, the shutter having the transition point E1 becomes ferromagnetic and attracted by the magnet 72.
As shown, the shutter opens and the guided light travels straight and propagates into the optical waveguide or optical fiber.

With the energy of the guided light, other shutters cannot be opened.

However, after the shutter having the transfer energy E1 is opened, the same shutter cannot be opened continuously.

Further, even when the shutter of E1 is continuously opened, the light energy beyond the opening of the shutter of E1 cannot be continuously output from E1.

This is because a shutter before E1 is opened.

When the shutter for the transfer energy E2 is opened, the heating energy of the guided light 1 is set between E2 and E3.

In this case, the shutter becomes paramagnetic because the shutter below E2 is above the Curie point, and the shutter does not open.

When the shutters of the transition energies E3 and E4 are opened, the same operation is performed as described above.

If it is not desired to open any of the shutters, it is sufficient to apply energy to the guided light above the Curie point of the medium having the highest energy (indicated here by E4).

As a result, all the shutters become paramagnetic, so that the shutters are not opened.

In the fourth embodiment, the magnetic phase change alloy 7
1, FeRh magnetic phase change alloy or FeRh
Although a FeRh magnetic phase change alloy in which elements such as Pd, Pt, and Ir are added to h is used, the invention is not necessarily limited to this.

In the fourth embodiment, a magnetic phase change alloy 71 having characteristics as shown in FIG. 13 is used as the magnetic phase change alloy 71 of the optical shutter 15 at each of the branch points 13A to 13D shown in FIGS. 1 and 2 by determining the pulse width of the guided light 1 or the number of light pulses having the same pulse width so that the heating energy can be set arbitrarily.
Since the magnetic phase change alloy 71 at any of the branch points 13A to 13D shown in FIG.
By changing the pulse width of the guided light 1 or the number of pulses having the same pulse width, the path of the guided light 1 can be changed by the guided light 1 itself.

[Fifth Embodiment] FIGS. 14 and 15 are views showing a schematic configuration of a light control type optical switch which is a fifth embodiment of the present invention.

In the fifth embodiment, as in the fourth embodiment, a magnetic phase change alloy 71 having a surface coated with a dielectric thin film 91 and a magnet 72 are combined as the optical shutter 15 shown in FIGS. It is a thing.

14 and 15, reference numeral 1 denotes a guided light;
Reference numeral 1 denotes an optical waveguide, 51 denotes a substrate of the optical waveguide 11, 71 denotes a FeRh magnetic phase change alloy having a surface coated with a dielectric thin film, or FeRhPt magnetic phase change alloy having a surface coated with a dielectric thin film; Is a magnet, 15
1 is a glass substrate, 152 is a groove formed in the glass substrate 151, 153 is a spring made of phosphor bronze, 154 is Fe
Shutter section having Rh magnetic phase change alloy, 155 is Fe
This is a shutter section having a RhPt magnetic phase change alloy.

In the fifth embodiment, an optical waveguide 11 having the same structure as that used in the second embodiment and having two branch points 13A and 13B as shown in FIG. 14 was manufactured.

Next, a 50% Fe, 50% Rh alloy and an alloy obtained by adding 5% of Pt to this alloy were prepared, and a thin film having a thickness of 4 μm was formed on a quartz glass substrate having a thickness of 100 μm by sputtering.

Thereafter, annealing was performed at 600 ° C. for 5 hours in a vacuum to make the composition and structure uniform.

The phase transition temperature of the two alloy films is 70 ° C. (Fe
Rh) and 120 ° C. (FeRhPt).

Thereafter, a SiN derivative film was formed on the magnetic film by sputtering at several thousand A, and the reflectance of each film was set to 30.
% And 60%.

By processing these elements together with the substrate, 20 μm
FeRh magnetic phase change alloy 71 having a size of m × 15 μm and coated on its surface with a dielectric thin film, or
FeRhPt whose surface is coated with a dielectric thin film
A magnetic phase change alloy 71 was prepared and used as a part of the shutter.

Next, a glass plate 151 having a groove 152 of a size just enough to receive the magnetic phase change alloy 71 therein and move the magnetic phase change alloy 71 therein is prepared. The magnetic phase change alloy 71 was inserted into the above.

However, the magnetic phase change alloy 71 has a thickness of 10 μm.
It was pressed in the direction opposite to the direction in which it always moved with a phosphor bronze spring of m diameter.

A 5 mm square NdFeB magnet 72 was set in the direction in which the magnetic phase change alloy 71 moved.

Further, a matching liquid was inserted between the magnetic phase change alloy 71 and the optical waveguide 11.

The guided light 1 was modulated by a modulator using a 1.3 μm semiconductor laser light to form a pulse light having a width of 100 ms.

When the pulse amplitude is 50 mW and the pulse interval is 200 ms or more, the shutter section 154 having the FeRh magnetic phase change alloy at the branch point 13A and the shutter section 155 having the FeRhPt magnetic phase change alloy at the branch point B do not change. The pulse light 1 propagated along the main path.

When the pulse interval is set to 150 ms, the temperature of the shutter portion 154 having the FeRh magnetic phase change alloy at the branch point 13A rises to the transition temperature or higher, and the FeRh magnetic phase change alloy becomes ferromagnetic and overcomes the drag of the spring. The FeR at the branch point 13A is drawn by the magnet 72.
The shutter portion 154 having the h magnetic phase change alloy was opened, and the pulse light 1 was emitted from the optical waveguide 11 in the direction of 23.

However, after 500 ms, the branch point 13A
1 having FeRh magnetic phase change alloy
54 was closed.

When the same pulse light 1 was applied, the shutter section 154 having the FeRh magnetic phase change alloy at the branch point 13A was opened again 500 ms later.

On the other hand, at the moment when the shutter 154 having the FeRh magnetic phase change alloy at the branch point 13A is closed,
When the pulse interval of the pulse light 1 was set to 50 ms, the shutter unit 154 having the FeRh magnetic phase change alloy at the branch point 13A slightly moved but did not open. Instead, the FeRhPt magnetic phase change alloy at the branch point 13B was replaced with the FeRhPt magnetic phase change alloy. The shutter unit 155 having the light was opened, and the pulsed light 1 was emitted in the direction from the optical waveguide 11 to 22.

In the fifth embodiment, a quartz-based material is used as the material of the optical waveguide 11, but the material is not necessarily limited to this.

Further, as the magnetic phase change alloy 71, FeR
Although an h magnetic phase change alloy or an FeRhPt magnetic phase change alloy was used, the invention is not necessarily limited thereto.

Although the dielectric thin film 91 is a SiN derivative film, it is not limited to this.

In the fifth embodiment, as in the fourth embodiment, arbitrary branch points 13A to 13D shown in FIGS.
Can change the magnetic phase change alloy 71 in ferromagnetic phase to ferromagnetic. Therefore, by changing the pulse width of the guided light 1 or the number of pulses having the same pulse width, the guided light 1 It is possible to change the route.

In each of the above embodiments, the waveguide light 1
As described above, the case of light propagating through an optical waveguide or an optical fiber has been described. However, the present invention is also applicable to the case of light propagating in space without using an optical waveguide.

Although the present invention has been described in detail with reference to the embodiments, it is needless to say that the present invention is not limited to the above-described embodiments and can be variously modified without departing from the gist thereof.

[0124]

As described above, according to the present invention,
In the optical control type optical switch, the optical shutter inserted at the branch point is deformed or moved by changing the wavelength of the guided light or the propagating light itself or by pulse modulation, so that the path is determined by itself. An optical control type optical switch can be realized.

Accordingly, it is necessary to provide wiring and optical components for controlling the optical switch. In particular, when a large number of branch points are arranged in multiple stages, the wiring occupies a space. Problem can be solved.

[Brief description of the drawings]

FIG. 1 is a schematic diagram for explaining the operation principle of a light control type optical switch of the present invention.

FIG. 2 is a schematic diagram for explaining the operation principle of the light control type optical switch of the present invention.

FIG. 3 is a diagram illustrating a schematic configuration of a light control type optical switch that is Embodiment 1 of the present invention.

FIG. 4 is a diagram illustrating a schematic configuration of a light control type optical switch that is Embodiment 1 of the present invention.

FIG. 5 is a diagram illustrating a schematic configuration of a light control type optical switch according to a second embodiment of the present invention.

FIG. 6 is a diagram illustrating a schematic configuration of a light control type optical switch according to a second embodiment of the present invention.

FIG. 7 is a diagram illustrating a schematic configuration of a light control type optical switch according to a third embodiment of the present invention.

FIG. 8 is a diagram illustrating a schematic configuration of a light control type optical switch according to a third embodiment of the present invention.

FIG. 9 is a diagram illustrating a schematic configuration of a light control type optical switch according to a fourth embodiment of the present invention.

FIG. 10 is a diagram illustrating a schematic configuration of a light control type optical switch according to a fourth embodiment of the present invention.

FIG. 11 is a graph showing the temperature change of the magnetization of the FeRh magnetic phase change alloy.

FIG. 12 is a graph showing a temperature rise with respect to heating energy when a dielectric film is coated on the surface of an FeRh magnetic phase change alloy and the light absorption coefficient is changed.

FIG. 13 shows a coating of a dielectric film on the surface of the FeRh alloy at each transition temperature shown in FIG. 11 so that a material having a lower transition temperature for light of a certain wavelength has a larger absorption coefficient and a transition temperature. It is a graph which shows the temperature change with respect to the heating energy of light at the time of making absorption coefficient low so that it may become high.

FIG. 14 is a diagram illustrating a schematic configuration of an optically controlled optical switch that is Embodiment 5 of the present invention.

FIG. 15 is a diagram illustrating a schematic configuration of an optically controlled optical switch that is Embodiment 5 of the present invention.

FIG. 16 is a diagram showing a schematic configuration of a conventional optical switch.

FIG. 17 is a diagram showing a schematic configuration of a conventional optical switch.

FIG. 18 is a diagram showing a schematic configuration of a conventional optical switch.

[Explanation of symbols]

1, guided light, 11, 11A, 11B, 11C, 11D,
11E, 12, 12A, 12B, 12C, 12D ... optical waveguide or optical fiber, 13, 13A, 13B, 13
C, 13D: branch point, 15: optical shutter, 35: shape memory alloy, 36: optical bandpass filter, 51: substrate for optical waveguide, 52: fixing point of shape memory alloy 35, 53: holding shape memory alloy 35 A glass substrate, 54: a hole formed in the glass substrate 53, 71: a magnetic phase change alloy, 72: a magnet,
91: dielectric thin film, 151: glass substrate, 152: groove formed in the glass substrate 151, 153: spring made of phosphor bronze, 154: shutter portion having a FeRh magnetic phase change alloy, 155: FeRhPt magnetic phase A shutter portion having a variable alloy, 105 ... electrodes, 110 ... incident guided light,
11: diffracted light, 112: transmitted light, 113: surface acoustic wave,
114 ... power supply, 115 ... comb-shaped electrode.

────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Bunichi Yoshimura 1-6, Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (56) References JP-A-2-12219 (JP, A) JP-A JP-A-61-285421 (JP, A) JP-A-60-162489 (JP, A) JP-A-62-299730 (JP, A) JP-A-63-194628 (JP, A) JP-A-5-207967 (JP, A) , A) (58) Field surveyed (Int. Cl. ⁷ , DB name) G02B 26/00-26/08

Claims (5)

(57) [Claims] 1. A combination of a wavelength filter that transmits only light of a specific wavelength and a shape memory alloy whose shape is changed by light irradiation, which is disposed on a surface of the wavelength filter opposite to a surface irradiated with light. An optical control type optical switch characterized in that an optical shutter comprising: is inserted at a branch point in an optical waveguide path. 2. A wavelength filter that transmits only light of a specific wavelength, and a magnetic phase change alloy which is disposed on a surface of the wavelength filter opposite to a surface irradiated with light and becomes ferromagnetic by light irradiation. An optical shutter composed of a combination is inserted at a branch point in the optical waveguide path, and a magnet for moving the magnetic phase change alloy that has become ferromagnetic is disposed near the magnetic phase change alloy. An optical control type optical switch, comprising: 3. An optical control type optical switch comprising at least two optical control type optical switches according to claim 1 or 2 installed in the same optical waveguide path, wherein the transmission wavelength of said wavelength filter is: A light control type optical switch, wherein each of the light control type optical switches is different. 4. An optical control type optical switch comprising at least two optical control type optical switches according to claim 1 or 2 installed in the same optical waveguide path, wherein the shape memory alloy has a shape change temperature. Or, the phase change temperature of the magnetic phase change alloy is different for each of the light control type optical switches. 5. A method for controlling a light control type optical switch according to claim 1, wherein guided light or propagation light is incident on the light control type optical switch according to claim 1 to perform a switch operation. The wavelength of the guided or propagated light;
Alternatively, a control method of a light control type optical switch, wherein a switch operation is performed according to an incident time.