JP2004145229A - Optical switch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical switch which is higher in reliability than an optical switch of the conventional mechanical system, is lower in cost and makes wavelength selection possible. <P>SOLUTION: The optical switch is provided with an electromagnetic driving system 1 consisting of a U-shaped magnetic core which is formed to a U shape having an intermediate section and two side piece sections and is wound with coils, a soft magnetic contact 2 which can face each of the side piece sections and is oscillatably supported and a permanent magnet which is arranged to add magnetic fluxes to the U-shaped magnetic core and the armature, a mirror 3 which is an optical path converting means fixed to the contact 2, an incident side optical fiber 4 for making light incident on the optical path converting means, and exit side optical fibers 5 and 6 to which the light subjected to optical path conversion by the optical path converting means is coupled. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an optical component used in an optical communication system or the like, and particularly to an optical switch suitable for switching an optical path, cutting off an optical path, or switching an optical path only for light having a specific wavelength.
[0002]
[Prior art]
Examples of the optical switch include a waveguide type optical switch using a quartz optical waveguide or a lithium niobate crystal optical waveguide, and a mechanical type optical switch that mechanically moves an optical fiber, a prism, and the like.
[0003]
A waveguide-type optical switch performs switching by changing the refractive index of a part of the optical waveguide by applying a current to a thin-film heater installed on the optical waveguide or applying a voltage to an electrode using an electro-optic effect. Do.
[0004]
Further, an example of an optical switch in which an optical waveguide is provided with a phase modulation element and an element having a total reflection function is disclosed in Patent Document 1 below.
[0005]
[Patent Document 1]
JP-A-5-297420
[0006]
Such a waveguide type optical switch has the advantage that it has no moving parts and high reliability, but has the disadvantage that it is generally expensive and has a large loss. The overwhelming number of optical switches are mechanical.
[0007]
The mechanical optical switch is lower in cost and smaller in loss than the waveguide type optical switch, but has a problem of low reliability due to the presence of the movable part.
[0008]
Recently, optical communication networks have been set up in various areas in cities, and optical switches are needed to realize the function of flexibly controlling the signal paths. Tall optical switches are required. Among them, in particular, with the spread of the wavelength division multiplexing communication system using a plurality of wavelengths, a demand for a wavelength selection type optical switch for switching only an optical signal of a specific wavelength is increasing.
[0009]
[Problems to be solved by the invention]
In the above situation, an object of the present invention is to provide an optical switch which has higher reliability, lower cost and wavelength selection than conventional optical switches of a mechanical system.
[0010]
[Means for Solving the Problems]
The optical switch according to the first configuration of the present invention has an intermediate portion and two side pieces, and has a U-shaped magnetic core around which a coil is wound, and is capable of opposing and swinging each of the side pieces. An electromagnetic driving system including a supported soft magnetic armature, a permanent magnet arranged to apply a magnetic flux to the U-shaped magnetic core and the armature, and at least one optical path conversion fixed to the armature; Means.
[0011]
In this configuration, the apparatus further includes an incident-side optical fiber that causes light to enter the optical path-changing unit, and an emission-side optical fiber to which the light whose path has been changed by the optical-path converting unit is coupled. At least one of the side optical fibers may be plural.
[0012]
Also, an incident-side optical system for guiding the light incident from the incident-side optical fiber to the optical path changing means, and an output-side optical system for guiding the light whose path has been converted by the optical path changing means to the output-side optical fiber. System.
[0013]
The swinging motion of the armature is driven by magnetic attraction between each side piece of the U-shaped magnetic core and the armature, and reciprocates around a central portion of the armature as a fulcrum. Oscillating motion by rotational motion can be used.
[0014]
Further, the optical path changing means may be formed of a mirror fixed on the armature and installed so that a light reflection direction is in a plane substantially parallel to a swing direction of the armature.
[0015]
Further, the optical path changing means may be formed of a mirror fixed on the armature and installed so that a light reflection direction is in a plane substantially perpendicular to a swing direction of the armature. .
[0016]
Further, at least one of the incident side optical fiber and the outgoing side optical fiber may be a plurality.
[0017]
The optical path changing means may be provided near the end of the armature facing the side piece of the U-shaped magnetic core on the armature.
[0018]
The optical switch according to the second configuration of the present invention has an intermediate portion and two side pieces, and has a U-shaped magnetic core around which a coil is wound, and is capable of opposing and swinging to each of the side pieces. A supported soft magnetic armature, an electromagnetic drive system including a U-shaped magnetic core and a permanent magnet arranged to apply a magnetic flux to the armature, and a light blocking unit fixed to the armature. It is characterized by having.
[0019]
In this configuration, further, at least one incident side optical fiber for entering light near the light blocking means, and at least one exit side optical fiber to which light incident from the incident side optical fiber is coupled. Can be prepared.
[0020]
Also, an incident side optical system for guiding light incident from the incident side optical fiber to the light blocking means, and an exit side optical system for guiding light incident from the incident side optical fiber to an exit side optical fiber. Can be provided.
[0021]
The swinging motion of the armature is driven by magnetic attraction between each side piece of the U-shaped magnetic core and the armature, and reciprocates around a central portion of the armature as a fulcrum. Oscillating motion by rotational motion can be used.
[0022]
Further, at least one of the incident side optical fiber and the outgoing side optical fiber can be plural.
[0023]
The light blocking means may be provided on the armature near the end of the U-shaped magnetic core facing the side piece.
[0024]
A third configuration of the present invention has an intermediate portion and two side pieces, and has a U-shaped magnetic core around which a coil is wound, and is supported so as to be able to oppose and swing to each of the side pieces. A soft magnetic armature, an electromagnetic drive system including a permanent magnet arranged to apply a magnetic flux to the U-shaped magnetic core and the armature, and only light in a specific wavelength range fixed to the armature. And a wavelength filter that reflects light.
[0025]
In this configuration, at least one incident side optical fiber for making light incident on the wavelength filter and at least one of light reflected by the wavelength filter or light transmitted through the wavelength filter is coupled. And one outgoing optical fiber.
[0026]
Further, an incident side optical system for guiding light incident from the incident side optical fiber to the wavelength filter, and light reflected by the wavelength filter or light transmitted through the wavelength filter is output light. And an emission-side optical system for guiding to the fiber.
[0027]
The swinging motion of the armature is driven by magnetic attraction between each side piece of the U-shaped magnetic core and the armature, and reciprocates around a central portion of the armature as a fulcrum. Oscillating motion by rotational motion can be used.
[0028]
Further, the wavelength filter is fixed near an end of the U-shaped magnetic core on the armature opposite to the side piece, and reflects light in a plane substantially perpendicular to the swinging direction of the armature. It can be installed to be.
[0029]
Then, at least one of the incident side optical fiber and the exit side optical fiber can be a plurality.
[0030]
In the optical switch according to the first, second or third configuration, the permanent magnet may be configured such that one end serving as one magnetic pole is located near the center of the intermediate portion of the U-shaped magnetic core and one end serving as the other magnetic pole. Can be arranged near the fulcrum of the swinging movement of the armature.
[0031]
The permanent magnet is a composite permanent magnet in which both ends are magnetic poles of the same polarity and the center is another magnetic pole, and can be inserted between side pieces of both ends of the U-shaped magnetic core.
[0032]
Then, either the N pole or the S pole of the permanent magnet contacts and is fixed to the armature, and can swing together with the armature.
[0033]
Further, it has a fixed-side insulator base that integrally holds the U-shaped core and the permanent magnet, and a movable-side insulator that holds the armature, and is integrally formed with the fixed-side insulator base. The U-shaped magnetic core and the permanent magnet may be fixed, and may be fixed while maintaining a state where the permanent magnet is in contact with a part of the U-shaped magnetic core.
[0034]
Further, a structure is provided that includes a hinge spring portion that supports the armature while applying an urging force or a deenergizing force to the rocking motion of the armature, and a movable spring portion that interlocks with the rocking motion of the armature. Can be.
[0035]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment of the present invention will be described with reference to FIGS.
[0036]
(Embodiment 1) FIG. 1 is a perspective view showing Embodiment 1 of an optical switch according to the present invention. FIGS. 1 (a) and 1 (b) show a state where the optical paths are switched to each other. .
[0037]
In FIG. 1, reference numeral 1 denotes an electromagnetic drive system, which is provided with an armature 2 supported so as to be swingable and an electrode terminal 10 for flowing a current to a coil included in the electromagnetic drive system 1.
[0038]
On the upper surface of one end of the armature 2, there is provided a mirror 3 formed by coating a reflective film on a thin glass plate or a crystal plate. , Output-side optical fibers 5 and 6 are provided, and a lens 7 for guiding the output light from the input-side optical fiber 4 to the mirror 3, and a lens 7 for guiding the light reflected by the mirror 3 to the output-side optical fiber 5 or 6. Lens 8 or 9 is installed, respectively.
[0039]
In addition, the electromagnetic drive system 1, the optical fibers 4, 5, 6, and the lenses 7, 8, 9 are fixed to one housing not shown in FIG. 1 by bonding, soldering, welding, or the like.
[0040]
FIG. 2 is a diagram showing the principle operation of Configuration Example 1 of the electromagnetic drive system used in the optical switch of FIG.
[0041]
In FIG. 2, a permanent magnet 22 is disposed in the center of the inside of a U-shaped iron core 21 around which a coil 19 is wound, and both ends of an armature 2 that performs oscillating motion at side pieces 21a and 21b at both ends are connected to each other. The permanent magnets 22 are arranged so as to face each other, and one end of the permanent magnet 22 is arranged as a fulcrum of the swinging movement of the armature. In the configuration example 1, the coil 19 is wound around the intermediate portion 21c. However, even if the coil 19 is wound around the side piece portions 21a and 21b, there is no change in the magnetic flux distribution generated by the coil current.
[0042]
In FIG. 2A showing the non-excited state of the coil 19, the armature 2 is attracted to one side piece 21 b by the magnetic flux φ 1 generated by the permanent magnet 22.
[0043]
Further, in FIG. 2B showing the coil excited state, the magnetic flux φ0 generated in the U-shaped iron core 21 by the excitation cancels the magnetic flux φ1 and is added to the magnetic flux φ2 in the other side portion 21a of the armature 2, The armature 2 swings about the fulcrum A and reverses in the other direction (clockwise). In this state, the armature 2 is attracted to the side piece 21a by the magnetic flux φ2 as shown in FIG.
[0044]
Further, in order to reverse this state and return to the state of FIG. 2A, the current direction of the coil may be reversed. Regarding the present electromagnetic drive system, a detailed principle and structure are described in Patent Document 2 below.
[0045]
[Patent Document 2]
JP-A-63-301441
[0046]
Next, the operation of the optical switch according to the first embodiment will be described with reference to FIG. FIG. 1A shows a state where the end of the armature 2 on the side opposite to the side where the mirror 3 is installed is attracted to the U-shaped iron core, and FIG. 1B shows the state where the mirror 3 is installed. The state where the side was sucked by the U-shaped iron core is shown.
[0047]
In FIG. 1A, light 11 from an incident side optical fiber 4 is collimated by a lens 7 and enters a mirror 3. The light 12 reflected upward by the mirror 3 is converged by the lens 8 and is coupled to the output side optical fiber 5.
[0048]
Next, in the state of FIG. 1B in which a current is applied to the coil from the electrode terminal 10 and the armature 2 is tilted in the opposite direction, the light 11 from the incident side optical fiber 4 is reflected by the mirror 3 in FIG. Is reflected in the opposite direction, becomes light 13, passes through the lens 9, is converged, and is coupled to the output side optical fiber 6.
[0049]
In order to return to the original state shown in FIG. 1A, a current in the opposite direction may be applied to the electrode terminal 10. As described above, the output port can be switched by applying the current to the electrode terminal 10.
[0050]
By the way, if the incident side optical fiber 4 and the exit side optical fiber 5 are arranged so that the direction of the light 12 reflected by the mirror 3 is in a plane parallel to the swinging direction of the armature 2, adjustment during manufacturing However, it is not always necessary to be in a parallel plane.
[0051]
The electromagnetic drive system having the structure shown in FIG. 2 used in the first embodiment has the same structure and principle as those used for the electromagnetic relay before, and has been used for more than several years and has high reliability. Has been established. Also, an inexpensive manufacturing method has been established. Further, the optical system components to be used are also commonly used in conventional optical devices, and the optical switch according to the first embodiment can be manufactured at low cost.
[0052]
FIG. 3 is a diagram showing a principle operation of a configuration example 2 of an electromagnetic drive system that can be used for the optical switch of the present invention.
[0053]
In FIG. 3, a composite permanent magnet 32 having an N pole at the center and S poles at both ends is inserted between side pieces at both ends of a U-shaped iron core 31 around which a coil 29 is wound. The two ends of the armature 30 that makes a rocking motion are arranged to face each of the pieces 31a and 31b. Further, a projection serving as a fulcrum of the swinging movement is provided at the center of the armature 30, and is arranged so as to be in contact with the center of the permanent magnet 32.
[0054]
In FIG. 3A showing one of the non-excited states of the coil 29, the armature 30 is attracted to one side piece 31b side by the magnetic flux φ1 generated by the permanent magnet 32.
[0055]
In FIG. 3 (b) showing the coil excitation state, the magnetic flux φ0 generated in the U-shaped iron core 31 by the excitation cancels the magnetic flux φ1 and is added to the magnetic flux φ2 in the other side portion 31a of the armature 30. Numeral 30 swings around the fulcrum A and reverses in the other direction (clockwise). In this state, even if the excitation of the coil 29 is cut off, as shown in FIG. 3C, the armature 30 is attracted to the side piece 31a by the magnetic flux φ2.
[0056]
Further, in order to reverse this state and return to the state of FIG. 3A, the current direction of the coil may be reversed. The present electromagnetic drive system has the same structure and principle as those used for electromagnetic relays, and high reliability and low-cost manufacturing methods have already been established. Regarding the present electromagnetic drive system, the detailed principle and structure are described in Patent Document 3 below.
[0057]
[Patent Document 3]
JP 2000-311568 A
[0058]
Here, as the structure of the electromagnetic drive system of FIGS. 2 and 3, a fixed-side insulator base that integrally holds a U-shaped iron core and a permanent magnet, and a movable-side insulator that holds the armature are formed in the U-shape. Since the permanent magnet and the U-shaped iron core are formed by integral molding while maintaining the state where the permanent magnet is in contact with a part of the iron core, there is no need to fix the permanent magnet and the U-shaped iron core with an adhesive, so that the standby required for curing the adhesive This has the advantage that no time is required. In addition, the process can be simplified by integral molding, and the positional accuracy between the U-shaped iron core, the permanent magnet, and the electric terminal can be improved.
[0059]
Further, as used in an electromagnetic relay, a hinge spring portion for supporting the armature while applying an urging force or a deenergizing force to the rocking motion of the armature, and a movable member interlocked with the rocking motion of the armature By providing the spring portion, an additional force is applied to the oscillating motion, and the power consumption required for performing the switching operation can be reduced.
[0060]
In addition, it is possible to check the fixed state of the oscillating motion by using the end of the movable spring portion as the electrical contact, and to grasp the switching state and stabilize the operation.
[0061]
FIG. 4 is a diagram showing a principle operation of a configuration example 3 of the electromagnetic drive system usable in the present invention.
[0062]
In FIG. 4, an armature 40 that performs oscillating motion is disposed at each of the two side pieces 41 a and 41 b of the U-shaped iron core 41 around which the coil 39 is wound so that both ends thereof are opposed to each other. A permanent magnet 42 having an N-pole on the armature 40 side and an S-pole on the opposite side is provided, and a central portion of the permanent magnet 42 is arranged so as to be a fulcrum of the swinging movement of the armature. At the center of the lower portion of the permanent magnet 42, a projection 43 made of a non-magnetic material is provided as a fulcrum of the swinging motion.
[0063]
In FIG. 4A showing the non-excited state of the coil 39, the armature 40 is attracted to one side piece 41b by the magnetic flux φ1 generated by the permanent magnet.
[0064]
Further, in FIG. 4B showing the coil excitation state, the magnetic flux φ0 generated in the U-shaped iron core 41 by the excitation cancels the magnetic flux φ1 and is added to the magnetic flux φ2 in the other side portion 41a of the armature 40. The armature 40 swings about the fulcrum A and reverses in the other direction (clockwise). In this state, even if the excitation of the coil 39 is stopped, as shown in FIG. 4C, the armature 40 is attracted to the side piece 41a by the magnetic flux φ2.
[0065]
Further, in order to reverse this state and return to the state of FIG. 4A, the current direction of the coil may be reversed. The present electromagnetic drive system has the same structure and principle as those used for electromagnetic relays, and high reliability and low-cost manufacturing methods have already been established.
[0066]
Further, as used in an electromagnetic relay, a hinge spring portion for supporting the armature while applying an urging force or a deenergizing force to the rocking motion of the armature, and a movable member interlocked with the rocking motion of the armature By providing the spring portion, an additional force is applied to the oscillating motion, and the power consumption required for performing the switching operation can be reduced.
[0067]
In addition, by using the end of the movable spring portion as an electrical contact, it is possible to check the fixed state of the oscillating motion, and to grasp the switching state and stabilize the operation.
[0068]
(Embodiment 2) FIG. 5 is a perspective view showing an optical switch according to Embodiment 2 of the present invention, and FIGS. 5 (a) and 5 (b) show a state where the respective optical paths are switched. .
[0069]
In FIG. 5, reference numeral 51 denotes an electromagnetic drive system, in which an armature 52 supported so as to be swingable and an electrode terminal 44 for flowing a current to a coil included in the electromagnetic drive system 51 are provided. A mirror 53 formed by coating a reflective film on a glass plate or a crystal plate is provided on the upper surface of one end of the armature 52, and the reflecting surface of the mirror 53 swings the armature 52. It is almost parallel to the direction.
[0070]
Further, with respect to the reflection surface of the mirror 53, the incident side optical fiber 54 and the exit side optical fiber 56, and the exit side optical fiber 57 and the exit side optical fiber 57 Each of the incident side optical fibers 55 is provided.
[0071]
Lenses 58 and 59 for guiding light emitted from the incident side optical fiber 54 or 55 to the mirror 53, and lenses 60 and 61 for guiding light reflected by the mirror 53 to the output side optical fiber 56 or 57, respectively. is set up.
[0072]
The electromagnetic drive system 51, the optical fibers 54, 55, 56, 57 and the lenses 58, 59, 60, 61 are fixed to one housing not shown in FIG. 5 by bonding, soldering, welding, or the like. .
[0073]
Further, in the second embodiment, the reflecting surface of the mirror 53 is provided substantially parallel to the swing direction of the armature 52, and the light reflecting direction is substantially perpendicular to the swing direction of the armature 52. However, the reflecting surface of the mirror 53 may be installed at an angle from a direction parallel to the swinging direction of the armature 52.
[0074]
The electromagnetic drive system 51 used in the second embodiment is the above-described electromagnetic drive system having any of the configurations shown in FIGS. 2, 3, and 4, and the operation thereof is described in the first embodiment. It is the same as
[0075]
Next, the operation of the optical switch according to the second embodiment will be described with reference to FIG. FIG. 5A shows a state in which the end of the armature 52 opposite to the side on which the mirror 53 is installed is attracted to the U-shaped iron core, and FIG. 5B shows the state where the mirror 3 is installed. The state where it was sucked by the U-shaped iron core is shown.
[0076]
In FIG. 5A, the light 45 from the incident side optical fiber 54 is collimated by the lens 58 and enters the mirror reflecting surface from the back side of the mirror 53. The light 46 reflected by the mirror 53 is converged by the lens 60 and is coupled to the output side optical fiber 56.
[0077]
On the other hand, light 47 from the incident side optical fiber 55 is collimated by the lens 59 and enters the mirror reflecting surface from the front side of the mirror 53. The light 48 reflected by the mirror 53 is converged by the lens 61 and is coupled to the output side optical fiber 57.
[0078]
Next, when a current is applied to the coil from the electrode terminal 44 and the armature 52 is tilted in the opposite direction, in the state of FIG. The light beams 45 and 47 pass above the mirror 53 and are coupled to the output side optical fibers 57 and 56 provided on the opposite sides of the mirror 53 via lenses 61 and 60, respectively.
[0079]
Further, in order to return to the original state of FIG. 5A, a current in the opposite direction may be applied to the electrode terminal 44.
[0080]
As described above, the output port can be switched by applying the current to the electrode terminal 44. Here, the shape and position of the mirror 53 and the light beam diameter are determined in consideration of the moving distance (normally 0.3 to 0.6 mm) of the end of the armature 52, and in the state of FIG. Is reflected, and in the state of FIG. 5B, most of the energy of light is set to pass.
[0081]
Further, the thickness of the substrate of the mirror 53 is set to a sufficiently small thickness of about 0.1 to 1 mm so that light loss does not increase in both optical path switching states.
[0082]
In the second embodiment, one mirror is provided only at one end of the armature to realize an optical switch for switching between 2 × 2 ports. However, the mirror is also provided at the other end of the armature. If two optical fibers are respectively disposed on the incident side and the output side with respect to the mirror, a 2-channel 2 × 2 port switching optical switch can be realized.
[0083]
In addition, a set of incident / reflection directions in multiple directions with respect to one mirror, for example, a plane perpendicular to the plane on which the incident-side and exit-side optical fibers are arranged in FIG. By installing a set of side optical fibers, a multi-channel optical switch can be configured.
[0084]
As described above, the electromagnetic drive system used in the second embodiment uses the drive system of the electromagnetic relay having high reliability, and the optical components to be used are low in cost, so that they are inexpensive and have high reliability. An optical switch can be realized.
[0085]
In FIG. 5, a light blocking type optical switch can be realized by changing the mirror 53 to a plate for blocking light such as metal.
[0086]
Further, in the examples of FIGS. 1 and 5, a lens is used to collimate the emitted light from the optical fiber and couple the collimated light to the optical fiber. However, a TEC fiber having an enlarged core portion is used as the optical fiber. This eliminates the need for a lens. Further, if the collimated light is generated in advance, the optical fiber is unnecessary.
[0087]
Incidentally, also in the second embodiment, in the electromagnetic drive system shown in FIG. 2 or FIG. 3, a fixed-side insulator base for integrally holding a U-shaped iron core and a permanent magnet, and a movable for holding the armature. By forming the side insulator and integral molding while maintaining the state where the permanent magnet is in contact with a part of the U-shaped iron core, it is not necessary to fix the permanent magnet and the U-shaped iron core with an adhesive, The advantage is that the waiting time required for curing the adhesive is not required. In addition, the process can be simplified by integral molding, and the positional accuracy between the U-shaped iron core, the permanent magnet, and the electric terminal can be improved.
[0088]
Further, in the electromagnetic drive system shown in FIG. 2, FIG. 3 or FIG. 4, a hinge spring portion for supporting the armature while applying an urging force or a deceleration force to the swinging motion of the armature, By providing the movable spring portion that is linked to the kinetic motion, an additional force is applied to the oscillating motion, and the power consumption required for performing the switching operation can be reduced. In addition, by using the end of the movable spring portion as an electrical contact, it is possible to check the fixed state of the oscillating motion, to grasp the switching state and to stabilize the operation.
[0089]
(Embodiment 3) FIG. 6 is a perspective view showing an optical switch according to Embodiment 3 of the present invention. FIG. 6 (a) shows a state where the optical path is switched only for light of a specific wavelength, FIG. 6B shows a state before the optical path is switched.
[0090]
In FIG. 6, reference numeral 51 denotes an electromagnetic drive system, in which an armature 52 supported so as to be swingable and an electrode terminal 44 for flowing a current to a coil included in the electromagnetic drive system are provided. A wavelength filter 63 formed by coating a dielectric multi-layer film on a glass plate or a crystal plate is provided on the upper surface of one end of the armature 52. The reflection surface of the wavelength filter 63 is 52 is substantially parallel to the swing direction.
[0091]
Here, the wavelength filter 63 is formed so as to reflect only the wavelength component of λi (i = 1, 2,...) Of the incident light and transmit the other wavelength components. For example, when the incident light is a light in which signal lights of five wavelengths of 1510 nm, 1530 nm, 1550 nm, 1570 nm, and 1590 nm are multiplexed, and λi is 1550 nm, light of 1550 nm is reflected by the wavelength filter 63, and others. Are transmitted through the wavelength filter 63.
[0092]
An incident side optical fiber 54 and an outgoing side optical fiber 56 are installed on the side of the reflection surface of the wavelength filter 63, and the two optical fibers are symmetric with respect to the light reflection point of the wavelength filter 63. The outgoing side optical fiber 57 and the incoming side optical fiber 55 are installed in various directions.
[0093]
Further, lenses 58 and 59 for guiding outgoing light from the incident-side optical fibers 54 and 55 to the wavelength filter 63, and light reflected by the wavelength filter 63 and light transmitted through the wavelength filter 63 are output to the output side. Lenses 60 and 61 for guiding to optical fibers 56 and 57 are provided, respectively.
[0094]
Note that the electromagnetic drive system 51, the optical fibers 54, 55, 56, 57 and the lenses 58, 59, 60, 61 are fixed to one housing not shown in FIG. 1 by bonding, soldering, welding, or the like. .
[0095]
The electromagnetic drive system 51 used in the third embodiment is the above-described electromagnetic drive system having any one of the configurations shown in FIGS. 2, 3, and 4, and its operation is described in the first embodiment. It is the same as
[0096]
Next, the operation of the optical switch according to the present embodiment will be described with reference to FIG.
[0097]
FIG. 6A shows a state in which the end of the armature 52 on the side opposite to the side where the wavelength filter 63 is installed is attracted to the U-shaped iron core, and FIG. The state where the installation side is adsorbed is shown.
[0098]
In FIG. 6A, light having n wavelengths from wavelengths λ1 to λn is multiplexed on the light propagating through the incident-side optical fiber. The light 45 emitted from the incident side optical fiber 54 is collimated by the lens 58 and enters the film surface from the back side of the wavelength filter 63. The light 46 of the wavelength λi reflected by the wavelength filter 63 is converged by the lens 60 and enters the output side optical fiber 56.
[0099]
On the other hand, light having a wavelength λi, which is emitted and modulated by a light source different from the light 45, propagates through the incident side optical fiber 55. The light 47 emitted from the incident side optical fiber 55 is collimated by the lens 59 and enters the film surface from the front side of the wavelength filter 63. The light of the wavelength λi reflected by the wavelength filter 63 and the lights of the wavelengths λ1, ‥, λi-1, λi + 1, ‥, λn emitted from the incident side optical fiber 54 and transmitted through the wavelength filter 63 are combined to form a light. The light is converged by the lens 61 and is coupled to the emission-side optical fiber 57.
[0100]
As a result, the light propagating through the input side optical fiber 54 is extracted only to the output side optical fiber 56 with the optical signal having the wavelength λi, and another optical signal having the wavelength λi is added and synthesized by the input side optical fiber 55 instead. The light is propagated to the emission side optical fiber 57.
[0101]
Next, in the state of FIG. 6B in which a current is applied to the coil from the electrode terminal 44 and the armature 52 is tilted in the opposite direction, the wavelength filter 63 moves downward and exits from the incident side optical fiber 54. Since the light 45 passes above the wavelength filter 63 and enters the output side optical fiber 57 via the lens 61, the original optical signal propagates to the output side optical fiber 57 as it is.
[0102]
Further, in order to return to the original state of FIG. 6A, a current in the opposite direction may be applied to the electrode terminal 44. As described above, the output port can be switched by applying the current to the electrode terminal 44.
[0103]
Here, the shape, position, and light beam diameter of the wavelength filter 63 are determined in consideration of the moving distance (normally 0.3 to 0.6 mm) of the end of the armature 52, and in the state of FIG. Is reflected, and in the state of FIG. 5B, most of the energy of light is set to pass. The thickness of the substrate of the wavelength filter 63 is set to a sufficiently small thickness of about 0.1 to 1 mm so that light loss does not increase in both optical path switching states.
[0104]
In the third embodiment, one wavelength filter is provided only at one end of the armature to realize an optical switch for switching. However, the other end of the armature has a different wavelength. If a wavelength filter that reflects light is installed, and two optical fibers for each of the incident side and the output side are similarly arranged for the wavelength filter, a two-channel switching optical switch can be realized.
[0105]
Further, in the third embodiment, the optical fiber is used to input or output the light having the wavelength λ, but the modulated light from the light source may be directly incident on the wavelength filter, and the reflected light from the wavelength filter may be reflected. Light may be directly input to the photodetector.
[0106]
The electromagnetic drive system having the structure shown in FIGS. 2, 3, and 4 used in the third embodiment is the same as that used in the conventional electromagnetic relay, as described in the other embodiments. The structure and principle have been in practical use for more than several years, and high reliability has been established. Also, an inexpensive manufacturing method has been established. In addition, the optical system components used are also commonly used in conventional optical devices, and the optical switch according to the third embodiment can be manufactured at low cost.
[0107]
Here, in the electromagnetic drive system shown in FIGS. 2 and 3, the fixed-side insulator base for integrally holding the U-shaped iron core and the permanent magnet and the movable-side insulator for holding the armature are formed in the U-shaped iron core. The permanent magnet and the U-shaped iron core do not need to be fixed with an adhesive by holding the state where the permanent magnet is in contact with a part of the adhesive, and the standby time required for curing the adhesive is eliminated. This has the advantage of eliminating the need. In addition, the process is simplified by the integral formation, and the positional accuracy between the U-shaped iron core, the permanent magnet, and the electric terminal can be improved.
[0108]
Further, the electromagnetic drive system shown in FIG. 2, FIG. 3 or FIG. 4 is provided with a hinge spring for supporting the swinging movement of the armature and a movable spring for interlocking with the swinging movement of the armature. , And the power consumption required for the switching operation can be reduced. In addition, by using the end of the movable spring portion as an electrical contact, it is possible to check the fixed state of the oscillating motion, and to grasp the switching state and stabilize the operation.
[0109]
In the third embodiment shown in FIG. 6, a lens is used to collimate the light emitted from the optical fiber and couple the collimated light to the optical fiber. However, a TEC fiber having an enlarged core portion is used as the optical fiber. This eliminates the need for a lens.
[0110]
Further, in the above embodiment, the optical fiber is used in the input section for introducing light into the optical switch or in the output section for extracting light therefrom, but a general optical waveguide is used. Alternatively, when the collimated light has already been generated, both the optical fiber and the lens can be omitted.
[0111]
In the above embodiment, the U-shaped iron core is used to guide the magnetic flux by the permanent magnet or the coil. However, a U-shaped core made of a general soft magnetic material may be used.
[0112]
【The invention's effect】
As is apparent from the above description, according to the present invention, by combining the electromagnetic drive system structure of the existing electromagnetic relay and simple optical components, the reliability is higher and the cost is lower than that of the conventional mechanical type optical switch. It is possible to provide an optical switch capable of selecting a wavelength and selecting a wavelength.
[Brief description of the drawings]
FIG. 1 is a perspective view of an optical switch according to a first embodiment. FIGS. 1A and 1B are diagrams showing a state where the optical paths are switched to each other.
FIG. 2 is a principle configuration diagram showing a configuration example 1 of an electromagnetic drive system used in the optical switch of the present invention. FIG. 2A shows a state without excitation by a coil, FIG. 2B shows a state excited by a coil, and FIG. 2C shows another state without excitation by a coil.
FIG. 3 is a principle configuration diagram showing a configuration example 2 of an electromagnetic drive system used in the optical switch of the present invention. FIG. 3A shows a state without excitation by a coil, FIG. 3B shows a state of excitation by a coil, and FIG. 3C shows another state without excitation by a coil.
FIG. 4 is a principle configuration diagram showing a configuration example 3 of an electromagnetic drive system used in the optical switch of the present invention. FIG. 4A shows a state without excitation by a coil, FIG. 4B shows a state excited by a coil, and FIG. 4C shows another state without excitation by a coil.
FIG. 5 is a perspective view of an optical switch according to a second embodiment. FIGS. 5A and 5B are diagrams showing a state where the optical paths are switched.
FIG. 6 is a perspective view of an optical switch according to a third embodiment. FIG. 6A illustrates a state where the optical path is switched only for light of a specific wavelength, and FIG. 6B illustrates a state before the optical path is switched.
[Explanation of symbols]
1,51 Electromagnetic drive system
2,30,40,52 armature
10,44 electrode terminals
11, 12, 13, 45, 46, 47, 48 light
19, 29, 39 coil
21,31,41 U-shaped iron core
21a, 21b, 31a, 31b, 41a, 41b Side piece
21c middle part
22, 32, 42 permanent magnet
3,53 mirror
4,54,55 Incident optical fiber
5,6,56,57 Outgoing side optical fiber
7, 8, 9, 58, 59, 60, 61 lenses
43 Projection
63 wavelength filter
A fulcrum
φ0, φ1, φ2 magnetic flux

Claims (23)

A U-shaped magnetic core having an intermediate portion and two side pieces, around which a coil is wound, a soft magnetic armature supported so as to be capable of swinging and opposing each of the side pieces; An optical switch comprising: an electromagnetic drive system including a U-shaped magnetic core and a permanent magnet arranged to apply a magnetic flux to the armature; and at least one optical path conversion unit fixed to the armature. . An incident-side optical fiber that causes light to enter the optical-path converting unit, and an emitting-side optical fiber to which light whose optical path has been converted by the optical-path converting unit is coupled. 2. The optical switch according to claim 1, wherein one of the optical switches is plural. 3. The optical system according to claim 1, further comprising: an incident-side optical system for guiding light to the optical path conversion unit; and an emission-side optical system for guiding light whose optical path is converted by the optical path conversion unit. 4. Light switch. The oscillating motion of the armature is driven by magnetic attraction between each side piece of the U-shaped core and the armature, and a reciprocating rotary motion around a central portion of the armature as a fulcrum. The optical switch according to claim 1, wherein the optical switch is a rocking motion. The optical path changing means comprises a mirror fixed on the armature and installed such that a light reflection direction is in a plane substantially parallel to a swing direction of the armature. 5. The optical switch according to any one of 1 to 4. The optical path changing means is characterized by comprising a mirror fixed on the armature and installed so that a light reflection direction is in a plane substantially perpendicular to a swing direction of the armature. The optical switch according to claim 1. The optical switch according to any one of claims 1 to 6, wherein the optical path changing means is provided near an end of the armature facing the side piece of the U-shaped magnetic core. A U-shaped magnetic core having an intermediate portion and two side pieces, around which a coil is wound, a soft magnetic armature supported so as to be capable of swinging and opposing each of the side pieces; An electromagnetic drive system comprising a U-shaped magnetic core and a permanent magnet arranged to apply a magnetic flux to the armature, and a light blocking means fixed to the armature and blocking a light beam. Light switch. At least one incident side optical fiber for entering light near the light blocking means, and at least one exit side optical fiber to which the light incident from the incident side optical fiber is coupled. The optical switch according to claim 8, wherein An incident-side optical system for guiding light to the light blocking means, and an exit-side optical system for guiding light incident from the incident-side optical fiber to an exit-side optical fiber. 10. The optical switch according to 8 or 9. The oscillating motion of the armature is driven by magnetic attraction between each side piece of the U-shaped core and the armature, and a reciprocating rotary motion around a central portion of the armature as a fulcrum. The optical switch according to claim 8, 9 or 10, wherein the optical switch is a rocking motion. The optical switch according to any one of claims 8 to 11, wherein the light blocking means is provided near an end of the armature facing the side piece of the U-shaped magnetic core on the armature. A U-shaped magnetic core having an intermediate portion and two side pieces, around which a coil is wound, a soft magnetic armature supported so as to be capable of swinging and opposing each of the side pieces; An electromagnetic drive system comprising a U-shaped magnetic core and a permanent magnet arranged to apply magnetic flux to the armature, and a wavelength filter fixed to the armature and reflecting only light in a specific wavelength range. An optical switch, characterized in that: At least one incident side optical fiber for entering light into the wavelength filter, and at least one output side to which at least one of light reflected by the wavelength filter and light transmitted through the wavelength filter is coupled; The optical switch according to claim 13, further comprising an optical fiber. An incident-side optical system for guiding the light incident from the incident-side optical fiber to the wavelength filter, and the light reflected by the wavelength filter or the light transmitted through the wavelength filter is transmitted to the output-side optical fiber. The optical switch according to claim 13, further comprising an emission-side optical system for guiding the light. The oscillating motion of the armature is driven by magnetic attraction between each side piece of the U-shaped core and the armature, and a reciprocating rotary motion around a central portion of the armature as a fulcrum. 16. The optical switch according to claim 13, 14 or 15, wherein the optical switch is a rocking motion. The wavelength filter is fixed near an end of the U-shaped magnetic core on the armature facing the side piece of the U-shaped magnetic core, and reflects light in a plane substantially perpendicular to a swing direction of the armature. The optical switch according to any one of claims 13 to 16, wherein the optical switch is installed in a light source. 18. The optical switch according to claim 14, wherein at least one of the incident side optical fiber and the exit side optical fiber is a plurality. The permanent magnet is arranged such that one end serving as one magnetic pole is located near the center of the intermediate portion of the U-shaped magnetic core, and one end serving as the other magnetic pole is located near a fulcrum of the swinging motion of the armature. The optical switch according to any one of claims 1 to 18, wherein: The permanent magnet is a composite permanent magnet in which both ends become the same magnetic pole and the center part becomes another magnetic pole, and is inserted between side pieces of both ends of the U-shaped magnetic core. The optical switch according to claim 1. 19. The optical switch according to claim 1, wherein one of an N pole and an S pole of the permanent magnet contacts and is fixed to the armature, and swings together with the armature. A fixed-side insulator base for integrally holding the U-shaped core and the permanent magnet; and a movable-side insulator for holding the armature. The core is integrally formed with the fixed-side insulator base. 21. The optical switch according to claim 19, wherein the U-shaped magnetic core and the permanent magnet are fixed, and fixed while maintaining a state where the permanent magnet is in contact with a part of the U-shaped magnetic core. A hinge spring portion for supporting the armature while applying an urging force or a deenergizing force to the rocking motion of the armature, and a movable spring portion interlocking with the rocking motion of the armature. Item 23. The optical switch according to any one of Items 19 to 22.

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