JP2007166817A - Micro-actuator, micro-actuator array, micro-actuator device, and optical switch system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent defective actuation and an operation delay from occurring easily by allowing a movable section to separate from a fixed section easily. <P>SOLUTION: The micro-actuator has the fixed section, and a movable plate 12 that can be moved between a first position separated from the fixed section and a second position in contact with the fixed section with respect to the fixed position. The fixed position has a fixed electrode 41a. The movable section is provided so that a returning force for returning to the first position is generated. The movable section comprises a movable electrode 22e for allowing an electrostatic force to be generated at a portion between the fixed electrode 41a by a voltage at a portion between the fixed electrode 41a, a current path 22c for a first Lorentz force for allowing the first Lorentz force to be generated in a direction toward the second position from the first position according to a control signal, and a current path 22d for a second Lorentz force for allowing a Lorentz force be generated in the direction toward the second position from the first position according to a control signal and in a reverse direction. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention

  With the progress of micromachining technology, the importance of microactuators is increasing in various fields. As an example of a field in which microactuators are used, for example, an optical switch used for optical communication or the like to switch an optical path can be cited. As an example of such an optical switch, for example, optical switches disclosed in the following Patent Documents 1 to 3 can be cited.

  The microactuator has a fixed portion and a movable portion on which a driven body (a mirror in the case of an optical switch) is mounted and is movable with respect to the fixed portion, and can hold the movable portion at a predetermined position. Configured as follows. For example, in the microactuator that moves the mirror employed in the optical switches disclosed in the following Patent Documents 1 to 3, the position where the movable portion abuts the fixed portion by electrostatic force (the position where the mirror passes the incident light as it is) ) To be held. In this microactuator, the movable portion is returned to and held by the spring force at a position where the movable portion is separated from the fixed portion (a position where the mirror reflects incident light). Further, Lorentz force is used when the movable part is moved from a position away from the fixed part to a position in contact with the fixed part. In this microactuator, since electrostatic force and Lorentz force are used as the driving force in this way, one current path for Lorentz force is provided in the movable portion in addition to the movable electrode for electrostatic force.

  The microactuator device disclosed in Patent Document 1 includes such a microactuator and a control unit that controls the microactuator. In this microactuator device, the control unit continues to hold the movable unit at a position in contact with the fixed unit when the mirror continues the state in which the incident light is allowed to pass through (the non-reflective state). Control the microactuator.

By the way, when a plurality of microactuators are arranged two-dimensionally to form an array, it may be required to reduce the number of wires to be drawn outside without mounting an address circuit or the like. The devices disclosed in Patent Documents 2 and 3 meet such a demand.
JP 2003-159698 A JP 2004-184564 A JP 2004-338045 A

  However, in the conventional microactuator devices disclosed in Patent Documents 1 to 3, if the mirror is kept in a non-reflective state for a long time, the movable part sticks to the fixed part and cannot be separated, resulting in malfunction. There is a possibility that an operation delay may occur because the movable part is difficult to be separated from the fixed part.

  The present invention has been made in view of such circumstances, and a microactuator in which a movable part is easily separated from a fixed part and does not easily cause malfunction or operation delay, and a microactuator array and a microactuator device using the microactuator And an optical switch system.

  In addition, the present invention makes it difficult for the movable part to move away from the fixed part, causing malfunctions and delays in operation, and also reduces the number of wires to be drawn outside without mounting an address circuit or the like when an array is formed. It is an object of the present invention to provide a microactuator that can be used, a microactuator array using the same, a microactuator device, and an optical switch system.

  In order to solve the above-described problem, the microactuator according to the first aspect of the present invention is configured such that the fixed portion is fixed between a first position away from the fixed portion and a second position abutting on the fixed portion. A movable portion provided so as to be movable relative to the portion, the fixed portion has a first electrode portion, and the movable portion has a return force to return to the first position. The movable part is provided in accordance with a control signal and a second electrode part capable of generating an electrostatic force between the movable part and the first electrode part due to a voltage between the first electrode part and the first electrode part. A first driving force generation unit capable of generating a driving force other than an electrostatic force in a direction from the first position toward the second position; and from the first position to the second position according to a control signal. A second driving force generator capable of generating a driving force other than electrostatic force in the direction toward and in the opposite direction; And it has a.

  The return force is not limited to the spring force. For example, when a piezoelectric element is used as the driving force generation unit, the return force is returned to the original position when the applied voltage to the piezoelectric element is reduced to zero. The power of This point is the same also about the aspect mentioned later.

  The microactuator according to a second aspect of the present invention is the microactuator according to the first aspect, wherein the first driving force generator is a first current path that is arranged in a magnetic field and generates a Lorentz force by energization, The second driving force generator is a second current path that is arranged in the magnetic field and generates Lorentz force by energization.

  The microactuator according to a third aspect of the present invention is the microactuator according to the second aspect, wherein one current path of the first and second current paths and the second electrode are electrically connected. Is.

  A microactuator device according to a fourth aspect of the present invention is a microactuator device comprising the microactuator according to any one of the first to third aspects, and a control unit that controls the operation of the microactuator, The control unit is configured so that the movable unit moves from the second position to the first position and the second position so that the movable unit is not continuously located at the second position for a predetermined time or more. The microactuator is controlled so as to perform an operation of returning to the second position after being located at a third position between the fixed portion and the third position.

  The microactuator device according to a fifth aspect of the present invention is the microactuator device according to the fourth aspect, wherein when the control unit holds the movable unit at the second position, the first and second electrode units A voltage is applied so that an electrostatic force is generated between them.

  In the microactuator device according to a sixth aspect of the present invention, in the fourth or fifth aspect, the third position is the return force and the first driving force generator or the second driving force generation. This is a position where the driving force in the direction from the first position toward the second position by the portion is balanced.

  A microactuator array according to a seventh aspect of the present invention includes a plurality of microactuators arranged two-dimensionally, and each of the plurality of microactuators is the microactuator according to any one of the first to third aspects. Yes, each row (or each column) is wired so that a control signal for the first driving force generator of the microactuator in that row (or column) is supplied simultaneously, and for each column (or each row) The control signals for the second driving force generation units of the microactuators in the column (or the row) are supplied at the same time.

  A microactuator device according to an eighth aspect of the present invention is a microactuator device comprising: the microactuator array according to the seventh aspect; and a control unit that controls operations of the plurality of microactuators. The movable portion is moved from the second position to the first position and the second position so that the movable portion of each microactuator is not located at the second position continuously for a predetermined time or more. The plurality of microactuators are controlled so as to perform an operation of returning to the second position after being positioned at a third position between the position and a third position away from the fixed portion. is there.

  The microactuator device according to a ninth aspect of the present invention is the microactuator device according to the eighth aspect, wherein when the control unit holds the movable part of each microactuator in the second position, A voltage is applied so that an electrostatic force is generated between the first and second electrode portions.

  In the microactuator device according to a tenth aspect of the present invention, in the eighth or ninth aspect, the third position of each microactuator is the return force of the microactuator and the first position of the microactuator. This is a position where the driving force in the direction from the first position toward the second position by the second driving force generator or the second driving force generator is balanced.

  An optical switch system according to an eleventh aspect of the present invention includes the microactuator device according to any one of the fourth to sixth and eighth to tenth aspects, and a mirror provided on the movable portion. It is.

  The optical switch system according to a twelfth aspect of the present invention is the optical switch system according to the eleventh aspect, wherein the mirror is one of a reflective state and a non-reflective state when the movable part is located at the first position. When the movable part is located at the second position and the third position, the mirror is in the other state of the reflection state and the non-reflection state.

  According to the present invention, it is possible to provide a microactuator in which the movable part is easily separated from the fixed part and does not easily cause malfunction or operation delay, and a microactuator array, a microactuator device, and an optical switch system using the microactuator. .

  In addition, according to the present invention, the movable part is easily separated from the fixed part, and it is difficult to cause an operation failure or an operation delay. In addition, when an array is formed, the number of wirings to be drawn outside is reduced without mounting an address circuit or the like. And a microactuator array, a microactuator device, and an optical switch system using the same.

  Hereinafter, a microactuator, a microactuator array, a microactuator device, and an optical switch system according to the present invention will be described with reference to the drawings.

  [First Embodiment]

  FIG. 1 is a schematic configuration diagram showing an optical switch system according to a first embodiment of the present invention. For convenience of explanation, as shown in FIG. 1, an X axis, a Y axis, and a Z axis that are orthogonal to each other are defined (the same applies to the drawings described later). In FIG. 1, an X ′ axis and a Y ′ axis indicate axes obtained by rotating the X axis and the Y axis by 45 ° around the Z axis, respectively. The surface of the substrate 11 of the optical switch array 1 is parallel to the XY plane. The direction of the arrow in the Z-axis direction is called the + Z direction or + Z side, and the opposite direction is called the -Z direction or -Z side, and the same applies to the X-axis direction and the Y-axis direction. The + side in the Z-axis direction may be referred to as the upper side, and the − side in the Z-axis direction may be referred to as the lower side.

  As shown in FIG. 1, this optical switch system includes an optical switch array 1, m optical input optical fibers 2, m optical output optical fibers 3, and n optical output optical fibers 4. In response to the optical path switching state command signal, the optical path switching state indicated by the optical path switching state command signal is realized in response to the magnet 5 as a magnetic field generating unit that generates a magnetic field as will be described later with respect to the optical switch array 1. And an external control circuit 6 serving as a control unit for supplying a control signal to the optical switch array 1. In the example shown in FIG. 1, m = 3 and n = 3, but m and n may each be an arbitrary number.

  In the present embodiment, the magnet 5 is a permanent magnet disposed on the lower side of the optical switch array 1 and applies a substantially uniform magnetic field toward the + side along the X-axis direction with respect to the optical switch array 1. It has occurred. However, instead of the magnet 5, for example, a permanent magnet having another shape, an electromagnet, or the like may be used as the magnetic field generation unit.

  As shown in FIG. 1, the optical switch array 1 includes a substrate 11 and m × n mirrors 31 arranged on the substrate 11. The m light input optical fibers 2 are arranged in a plane parallel to the XY plane so as to guide incident light in the Y′-axis direction from one side in the Y′-axis direction with respect to the substrate 11. The m optical output optical fibers 3 are arranged on the other side of the substrate 11 so as to face the m optical input optical fibers 2 and are not reflected by any mirror 31 of the optical switch array 1. Are arranged in a plane parallel to the XY plane so that light traveling in the Y′-axis direction is incident on the XY plane. The n light output optical fibers 4 are arranged in a plane parallel to the XY plane so that light reflected by any mirror 31 of the optical switch array 1 and traveling in the −X′-axis direction is incident. ing. The m × n mirrors 31 can be moved in and out by a microactuator described later with respect to the intersection of the outgoing optical path of the m optical input optical fibers 2 and the incident optical path of the optical output optical fiber 4. It is arranged on the substrate 11 in a two-dimensional matrix so that it can move in the Z-axis direction. In this example, the orientation of the mirror 31 is set so that the normal line thereof is parallel to the Y axis that forms 45 ° with the Y axis ′ in a plane parallel to the XY plane. However, the angle can be changed as appropriate. When the angle of the mirror 31 is changed, the direction of the optical fiber 4 for light output may be set according to the angle. The optical path switching principle of this optical switch system is the same as the optical path switching principle of the conventional two-dimensional optical switch.

  FIG. 2 is a schematic plan view schematically showing the optical switch array 1 in FIG. The optical switch array 1 includes a substrate 11 (not shown in FIG. 2), m × n movable plates 12 arranged two-dimensionally on the substrate 11, and mirrors 31 mounted on each movable plate 12. And. In FIG. 1 and FIG. 2 and the drawings to be described later, nine optical switches are arranged in 3 rows and 3 columns for the sake of simplicity, but the number of optical switches is not limited at all. Portions other than the mirror 31 in the optical switch array 1 constitute a microactuator array. In the present invention, the microactuator and the optical switch may be used alone without being arrayed.

  Next, the structure of one optical switch as a unit element of the optical switch array 1 in FIG. 1 will be described with reference to FIGS.

  FIG. 3 is a schematic plan view schematically showing one optical switch as a unit element of the optical switch array 1 in FIG. FIG. 4 is a schematic cross-sectional view along the line A-A ′ in FIG. 3. However, FIG. 4 shows only a cross section of the movable plate 12. FIG. 5 is a diagram showing a pattern shape of the Al film 22 when the movable plate 12 in FIG. 3 is viewed from above. In order to facilitate understanding, in FIG. 5, the Al film 22 is indicated by hatching. In FIG. 5, the fixed electrode 41a formed on the substrate 11 is also indicated by a broken line. FIG. 6 is a schematic cross-sectional view of the cross section taken along the line B-B ′ in FIGS. 3 and 5 when viewed from the + Y side in the −Y axis direction. However, FIG. 6 also shows the mirror 31 viewed in the −Y-axis direction. FIG. 6 shows a state in which the mirror 31 is held on the upper side and has advanced into the optical path. In FIG. 6, for convenience of drawing notation, the convex portion 24 described later is omitted and is shown as having no step.

  As shown in FIGS. 2 and 3, one optical switch as a unit element of the optical switch array 1 is provided on a substrate 11 such as a silicon substrate, and 1 as a movable part constituting one microactuator together with the substrate 11. Two movable plates 12 and a mirror 31 as an optical element which is a driven body mounted on the movable plate 12 are provided.

  The movable plate 12 is composed of a thin film, and as shown in FIGS. 3 to 6, the lower silicon nitride film (SiN film) 21 and the upper SiN film 23 over the entire planar shape of the movable plate 12, and these The intermediate Al film 22 is partially formed between the first and second films 21 and 23. That is, the movable plate 12 includes a part composed of a two-layer film in which SiN films 21 and 23 are laminated in order from the bottom, and a part composed of a three-layer film in which the SiN film 21, Al film 22, and SiN film 23 are laminated in order from the bottom. Have both. The pattern shape of the Al film 22 is as shown in FIG. 5, which will be described later. The movable plate 12 faces upward with respect to the substrate 11 as shown in FIG. 6 due to the internal stress generated by the difference in thermal expansion coefficient between the SiN films 21 and 23 and the Al film 22 and the internal stress generated at the time of film formation ( The film is formed with a predetermined film thickness and film formation conditions so as to be curved in the + Z direction.

  As shown in FIG. 3, the movable plate 12 includes a rectangular mirror mounting plate 12a as a mounting portion for mounting the mirror 31 (that is, a support base for the mirror 31), and an end portion of the mirror mounting plate 12a. And two strip-shaped support plates 12b connected to each other. In the present embodiment, these two support plates 12b are two beam portions mechanically connected in parallel to each other. The support plate 12b has a leg portion 12c and a leg portion 12d at each end. The legs 12c and 12d are both fixed to the substrate 11, and the movable plate 12 is lifted on the mirror mounting plate 12a side with the legs 12c and 12d as fixed ends, as shown in FIG. Thus, in the present embodiment, the movable plate 12 is a movable portion having a cantilever structure with the leg portions 12c and 12d as fixed ends. In the present embodiment, the substrate 11 and insulating films 13, 14, 15 and the like, which will be described later, laminated on the substrate 11 constitute a fixed portion.

  As shown in FIG. 3, the movable plate 12 is provided with a convex portion 24 so as to surround a region including a portion where the mirror 31 of the movable plate 12 is mounted. As shown in FIG. 4, the convex portion 24 is formed by making the multilayer film constituting the movable plate 12 convex. By providing the convex portion 24 in this manner, a step is generated. Therefore, in the movable plate 12, the region surrounded by the convex portion 24 and the region provided with the convex portion 24 are suppressed from bending due to internal stress and are flat. Sex can be maintained. Therefore, even when the movable plate 12 is in a state where the mirror 31 is lifted to the upper position by bending due to internal stress as shown in FIG. The shape of the mirror 31 can be kept constant.

  As described above, in the movable plate 12, the region surrounded by the convex portion 24 and the region provided with the convex portion 24 are suppressed from being curved, but the region close to the leg portion 12 d of the support plate 12 b has the convex portion 24. Not provided. Thereby, due to the curvature of the region of the support plate 12b where the convex portion 24 is not provided, the movable plate 12 is lifted on the mirror mounting plate 12a side as shown in FIG. 6 with the leg portions 12c and 12d as fixed ends. ing. Moreover, the area | region near the leg part 12d of the support plate 12b becomes the leaf | plate spring part as an elastic part by the convex part 24 not being provided.

  Here, the shape of the Al film 22 of the movable plate 12 will be described with reference to FIG. In the present embodiment, the Al film 22 is patterned into a shape as shown in FIG. 5 in order to drive the movable plate 12 using a total of three forces of two Lorentz forces and an electrostatic force as driving forces. .

  The pattern 22 a of the Al film 22 extends from each of the two leg portions 12 d along the outer peripheral edge of the movable plate 12 to the distal end side (+ X side) of the movable plate 12, and one side of the distal end of the movable plate 12. 12e is connected to a linear pattern 22c extending in the Y-axis direction along 12e. The pattern 22c is a first current path (first current path for Lorentz force) that is arranged in a magnetic field and generates a first Lorentz force as a driving force when energized. Hereinafter, the pattern 22c may be referred to as a first Lorentz force current path 22c. The pattern 22 c is also a pattern in the Al film 22. The pattern 22a is a wiring pattern for supplying current to the Lorentz force current path 22c. As shown in FIG. 6, the pattern 22a is connected to the wiring pattern 42a made of an Al film or the like through the contact hole of the insulating film 15 and the SiN film 21 in the leg portion 12d on the + Y side, and the leg on the −Y side. Similarly, another wiring pattern (not shown in FIG. 6) is connected to the portion 12d, and a current as a first Lorentz force drive signal is supplied from these wiring patterns via the leg portion 12d. The Lorentz force current path 22c is placed in the magnetic field in the X-axis direction by the magnet 5 shown in FIG. Accordingly, when a current is supplied to the Lorentz force current path 22c via the pattern 22a, a Lorentz force in the + Z direction or the −Z direction is generated in the first Lorentz force current path 22c depending on the direction of the current.

  As shown in FIGS. 6 and 7, insulating films 13, 14, and 15 such as silicon oxide films are stacked on the substrate 11 sequentially from the substrate 11, and the wiring pattern 42a is formed between the insulating films 14 and 15. Is formed.

  The pattern 22b of the Al film 22 extends from each of the two leg portions 12c along the inner edge of the movable plate 12 to the tip side (+ X side) of the movable plate 12, and is adjacent to the pattern 22c and parallel to it. Then, it is connected to a linear pattern 22d extending in the Y-axis direction. The pattern 22d is a second current path (second Lorentz force current path) that is arranged in the magnetic field and generates a second Lorentz force as a driving force when energized. Hereinafter, the pattern 22d may be referred to as a second Lorentz force current path 22d. The pattern 22 d is also a pattern in the Al film 22. Since the shape of the second current path for Lorentz force 22d has substantially the same shape as that of the first current path for Lorentz force 22c, if currents of the same magnitude are flowed in opposite directions to each other, The Lorentz forces generated in the two are almost the same and in opposite directions cancel each other.

  The pattern 22b is connected to a rectangular pattern 22e disposed on the distal end side of the movable plate 12. The pattern 22e is a movable electrode for generating an electrostatic force as a driving force. Hereinafter, the pattern 22e may be referred to as the movable electrode 22e. The patterns 22e and 22b are also patterns in the Al film 22.

  The pattern 22b is a wiring pattern for supplying a current to the Lorentz force current path 22d and for applying a potential to the movable electrode 22e. The pattern 22b is connected to a wiring pattern (not shown in FIG. 6) made of an Al film or the like through the contact hole of the insulating film 15 and the SiN film 21 in the leg portion 12c on the + Y side, and the leg on the −Y side. Similarly, the part 12c is connected to another Lorentz force wiring pattern (not shown in FIG. 6). A current as a second Lorentz force drive signal is supplied from these wiring patterns via the leg 12c. The Lorentz force current path 22d is placed in the magnetic field in the X-axis direction by the magnet 5 shown in FIG. Accordingly, when a current is supplied to the Lorentz force current path 22d via the pattern 22b, a Lorentz force in the + Z direction or the −Z direction is generated in the Lorentz force current path 22d depending on the direction of the current. Further, a voltage (electrostatic force voltage, electrostatic force drive signal) is applied between the current supply state and the fixed electrode 41a made of an Al film. As shown in FIGS. 5 and 6, the fixed electrode 41a is formed between the insulating films 13 and 14 on the substrate 11, and is disposed at a position facing the movable electrode 22e. When a voltage is applied between the movable electrode 22e and the fixed electrode 35, an electrostatic force as a driving force is generated between them, and the movable plate 12 is attracted to the substrate 11 by this electrostatic force.

  In the present embodiment, the electrostatic force voltage between the movable electrode 22e and the fixed electrode 41a, the current flowing through the first Lorentz force current path 22c, and the current flowing through the first Lorentz force current path 22d are controlled. As a result, the mirror 31 is held on the upper side (opposite side of the substrate 11) (FIG. 6, FIG. 7A described later), and the mirror 31 is held at the lower position shown in FIG. 7C described later. In this state, the mirror 31 can be held at the lower intermediate position shown in FIG. In the present embodiment, as described later, such control is performed by the external control circuit 6.

  FIG. 7 is a schematic side view schematically showing each position where the movable part of one optical switch and the mirror 31 provided thereon are held. In FIG. 7, the structure of each part is shown greatly simplified. 6 and 7, K indicates a cross section of the optical path with respect to the advance position of the mirror 31. FIG. 7A shows the same state as FIG.

  Here, what control signals are given to hold the mirror 31 of one optical switch shown in FIGS. 3 to 6 at each position shown in FIG. 7 will be described with reference to FIG. FIG. 8 is an explanatory diagram showing an example of a control signal given to one optical switch. 8, elements that are the same as or correspond to those in FIG. 5 are given the same reference numerals, and redundant descriptions thereof are omitted.

  Here, to facilitate understanding, it is assumed that the changeover switches SWR and SWL, the variable DC voltage sources VV and VH, and the variable DC current sources IV and IH are connected as shown in FIG.

  As shown in FIG. 8, in the leg portion 12d on the -Y side, the pattern 22a is connected to the ground (ground). On the other hand, a variable DC current source IV is connected between the pattern 22a in the leg portion 12d on the + Y side and the ground. Therefore, the current from the variable DC current source IV becomes the first Lorentz force current flowing in the first Lorentz force current path 22c. The variable DC current source IV includes, for example, a positive current + I (a setting example of this value will be described later) and a variable current having a value from zero to a negative current −I (a setting example of this value will be described later). Can be output. Here, the positive current refers to a current that generates a first Lorentz force in the −Z direction (direction toward the substrate 11) in the first Lorentz force current path 22c, and the negative current refers to the first Lorentz force. A current that generates a first Lorentz force in the + Z direction (a direction away from the substrate 11) in the force current path 22c.

  The changeover switches SWR and SWL are switched in conjunction with each other, and the changeover switch SWR is selectively connected between the contacts a1 and c1 and is selectively connected between the contacts a2 and c2 of the changeover switch SWL. Switching between the contacts b1 and c1 of the SWR is selectively connected and the contacts b2 and c2 of the changeover switch SWL are selectively connected.

  As shown in FIG. 8, the common contact c1 of the changeover switch SWR is connected to the pattern 22b at the leg portion 12c on the + Y side. A variable DC voltage source VH is connected between the switching contact a1 of the changeover switch SWR and the ground. The variable DC voltage source VH can selectively apply, for example, a negative potential −V (a setting example of this value will be described later) and a zero potential (ground potential) with reference to the ground potential to the switching contact a1. Shall. A variable DC current source IH is connected between the switching contact b1 of the changeover switch SWR and the ground. The variable DC current source IH outputs a variable current having a value from zero to a positive current + I when the changeover switches SWR and SWL are switched to the switching contacts b1 and b2 side (that is, the variable DC current source IH side). It shall be possible. Here, the positive current refers to a current that generates a second Lorentz force in the −Z direction (direction toward the substrate 11) in the second current path 22d for Lorentz force.

  As shown in FIG. 8, the common contact c2 of the changeover switch SWL is connected to the pattern 22b at the −Y side leg 12c. The switching contact a2 of the changeover switch SWL is electrically floating, and the switching contact b2 of the changeover switch SWL is connected to the ground.

  Therefore, when the changeover switches SWR and SWL are switched to the switching contacts b1 and b2 side (that is, the variable DC current source IH side), the current from the variable DC current source IH is supplied to the second Lorentz force current path 22d. This is the second current for Lorentz force that flows. In this switching state, when the second current for Lorentz force flows from the variable DC current source IH, a voltage drop occurs due to the electric resistance of the patterns 22b and 22d. However, since the electric resistances of the patterns 22b and 22d are small, the voltage drop of the patterns 22b and 22d due to the second current for Lorentz force is almost zero, so that the movable electrode 22e has almost zero with respect to the ground potential. (Approximately ground potential) is applied. Since the voltage drop of the patterns 22b and 22d due to the second Lorentz force current can be made smaller than the potential applied by the variable DC voltage source VV, it can be ignored. That is, when the changeover switches SWR and SWL are switched to the variable DC current source IH side, the potential applied to the movable electrode 22e is approximately zero with respect to the ground potential (that is, the ground potential). Potential). In the following description, it is assumed that the potential of the movable electrode 22e is zero in such a state.

  On the other hand, when the changeover switches SWR and SWL are switched to the switching contacts a1 and a2 side (that is, the variable DC voltage VH side), the second Lorentz force current flows in the second Lorentz force current path 22d. Instead, the potential from the variable DC voltage source VH with respect to the ground potential is applied to the movable electrode 22e.

  Further, as shown in FIG. 8, a variable DC voltage source VV is connected between the fixed electrode 41a and the ground. The variable DC voltage source VV can, for example, selectively apply a positive potential + V (a setting example of this value will be described later) and a zero potential (ground potential) with respect to the ground potential to the fixed electrode 41a. And

  FIG. 7A shows the state in which the electrostatic force (electrostatic force between the two due to the voltage (potential difference) between the fixed electrode 41a and the movable electrode 22e) and the first and second Lorentz forces are not applied. Show. Also, when the same Lorentz force current flows in the opposite directions to the Lorentz force current paths 22d and 22e with the changeover switches SWR and SWL switched to the variable DC current source IH side, Since the first and second Lorentz forces generated in the above are almost the same and are opposite to each other and cancel each other, the state is almost as shown in FIG. In other words, in the state shown in FIG. 7A, when the same currents for the Lorentz force flow through the Lorentz force current paths 22d and 22e in opposite directions, the state shown in FIG. 7A is maintained. can do. In the state shown in FIG. 7A, even if the voltage between the fixed electrode 41a and the movable electrode 22e is V or 2V, the distance between the fixed electrode 41a and the movable electrode 22e is sufficiently long. The electrostatic force acting between the two is sufficiently small, and the state shown in FIG.

  The current and voltage supplied to the optical switch by the switching state of the changeover switches SWR and SWL and the outputs of the variable DC voltage sources VV and VH and the variable DC current sources IV and IH are control signals for the optical switch. . Examples of control signals necessary for maintaining each state shown in FIG. 7 will be understood from the following description.

  In the state shown in FIG. 7A, the movable plate 12 returns to the state curved in the + Z direction by the spring force of the leaf spring portion formed by the region near the leg portion 12d of the support plate 12b, and the movable portion is moved from the fixed portion. The mirror 31 is held away from the upper position. As a result, the mirror 31 advances into the optical path K, reflects the light incident on the optical path K, and enters a reflective state.

  The state shown in FIG. 7B is, for example, in a state where the electrostatic force is not applied and only one of the variable DC current sources IV and IH and only one of the current paths 22c and 22d for Lorentz force. This is a state that is maintained when a positive current of a predetermined magnitude is applied to generate a downward Lorentz force (of course, there are countless other current settings). In this state, the downward Lorentz force balances with the spring force of the movable plate 12 at a position where the movable portion does not contact the fixed portion and leaves a space from the fixed portion (lower intermediate position). Then, the movable plate 12 and the mirror 31 are held at the lower intermediate position. The space is set to a distance at which a sufficient electrostatic force can be generated between the movable electrode 22e of the movable plate 12 and the fixed electrode 41a of the fixed portion. In this state, the mirror 31 leaves the optical path K, and the light incident on the optical path K passes through the mirror 31 without being reflected by the mirror 31 and enters a non-reflective state.

  In the state shown in FIG. 7B, a predetermined voltage is sufficiently applied between the movable electrode 22e of the movable plate 12 and the fixed electrode 41a of the fixed portion by the variable DC voltage source VH and / or the variable DC voltage source VV. When an electrostatic force is applied, the movable plate 12 and the mirror 31 are further moved downward by the electrostatic force, and as shown in FIG. 7C, at the lower position where the movable plate 12 abuts the fixed portion. Quiesce.

  Specifically, the transition from the state shown in FIG. 7B to the state shown in FIG. 7C is performed, for example, when a positive first Lorentz force current having a predetermined magnitude is generated by the variable DC current source IV. When the changeover switches SWR and SWL are switched to the variable DC voltage source VH side, a negative potential having an absolute value greater than or equal to a predetermined value is applied to the movable electrode 22e, and a zero potential is applied to the fixed electrode 41a. (Ground potential) is applied, a zero potential (ground potential) is applied to the movable electrode 22e and a positive potential having an absolute value greater than or equal to a predetermined value is applied to the fixed electrode 41a, or a predetermined potential is applied to the movable electrode 22e. This is achieved by applying a negative potential having an absolute value greater than or equal to the value and applying a positive potential having an absolute value greater than or equal to the predetermined value to the fixed electrode 41a. Further, in the transition from the state shown in FIG. 7B to the state shown in FIG. 7C, the current from the variable DC current source IV does not flow, and the changeover switches SWR and SWL are on the variable DC current source IH side. When the second Lorentz force current is supplied from the variable DC current source IH to the second Lorentz force current path 22d, as described above, the potential of the movable electrode 22e is zero (ground potential). Therefore, this is achieved by applying a negative potential having an absolute value greater than or equal to a predetermined value to the fixed electrode 41a by the variable DC voltage source VV.

  After shifting from the state shown in FIG. 7B to the state shown in FIG. 7C, the current for the first or second Lorentz force that has flowed until then is made zero, and the first or second Lorentz force is made. The application of is stopped. Even if the application of the Lorentz force is stopped, since the electrostatic force is applied, the movable plate 12 and the mirror 31 continue to be held at the lower position shown in FIG.

  Also in the state shown in FIG. 7C, the mirror 31 has left the optical path K and is in a non-reflective state as in the state shown in FIG. 7B.

  Note that the state shown in FIG. 7C can be maintained under certain conditions even when the magnitude of the flowing current or the magnitude of the potential varies.

  When the first and second currents for Lorentz force do not flow in the first and second Lorentz force current paths 22c and 22d, respectively, a negative potential having an absolute value greater than or equal to a predetermined value is applied to the movable electrode 22e. Whether a zero potential (ground potential) is applied to the fixed electrode 41a or a zero potential (ground potential) is applied to the movable electrode 22e and a positive potential having an absolute value greater than or equal to a predetermined value is applied to the fixed electrode 41a. Alternatively, a negative potential having an absolute value greater than or equal to a predetermined value is applied to the movable electrode 22e, and a positive potential having an absolute value greater than or equal to the predetermined value is applied to the fixed electrode 41a, as shown in FIG. The state can be maintained.

  Next, a case where a negative first Lorentz force current is caused to flow through the first Lorentz force current path 22c and no second Lorentz force current is flowing through the second Lorentz force current path 22d. ,explain. Here, the positive current of the magnitude required for pulling down the movable plate 12 from the position shown in FIG. 7A to the position shown in FIG. 7B is + I, which is the same size and the flow direction is reverse. Is defined as -I. This negative current −I generates a Lorentz force in a direction (+ Z direction) in which the movable plate 12 is moved away from the substrate 11. In an operation example described later, it is necessary to maintain the state shown in FIG. 7C in a state where the positive current −I is applied. The magnitude of the potential difference between the fixed electrode 41a and the movable electrode 22e necessary to achieve this can be set in principle. That is, a voltage V corresponding to a potential difference that is slightly larger than the lower limit of the magnitude of the potential difference (as requested by practical reasons) is defined, and is −V if negative and + V if positive. A potential −V is applied to the movable electrode 22e and a zero potential is applied to the fixed electrode 41a, a zero potential is applied to the movable electrode 22e and a potential + V is applied to the fixed electrode 41a, or a potential is applied to the movable electrode 22e. When −V is applied and the potential + V is applied to the fixed electrode 41a, the state shown in FIG. 7C can be maintained even if the negative current −I is caused to flow through the first current path 22c for Lorentz force. it can.

  In the state shown in FIG. 7C, the electric potential of the fixed electrode 41a and the electric potential of the movable electrode 22e are both set to zero potential without flowing current through the first and second Lorentz force current paths 22c and 22d. When the application of the second Lorentz force and the electrostatic force is stopped, the state shown in FIG. On the other hand, in the state shown in FIG. 7C, when a positive current + I is passed through one of the first and second Lorentz force current paths 22c and 22d, the state shown in FIG. 7B is obtained.

  Although the driving method using the DC voltage sources VH and VV has been described here, driving using an AC voltage is also possible. For that, a method similar to the method disclosed in Patent Document 3 can be applied.

  Focusing on one optical switch, in the present embodiment, the lower position shown in FIG. 7C is set so that the movable plate 12 does not continue to be located at the lower position shown in FIG. Then, after the light is positioned at the lower intermediate position shown in FIG. 7B, the operation returns to the lower position shown in FIG. 7C (referred to as “contact continuation stopping operation”). The microactuator of the switch is controlled. In order to realize this control, for example, while the non-reflecting state is maintained for a long time, the movable plate 12 is moved to the lower intermediate position shown in FIG. 7B and the lower position shown in FIG. What is necessary is just to control the microactuator of the said optical switch so that it may be located in a side position alternately. Specific control signals necessary for this can be understood from the above description.

  As described above, in the present embodiment, even when the non-reflective state is maintained for a long time, the duration in which the mirror 31 and the movable plate 12 are located at the lower position shown in FIG. 7C. Therefore, the movable plate 12 is difficult to stick to the fixed portion, and the movable portion is easily separated from the fixed portion when returning from the position shown in FIG. 7C to the position shown in FIG. Therefore, it becomes difficult to cause malfunction and delay in operation.

  By the way, if only the sticking between the movable plate 12 and the fixed portion is prevented, the electrostatic force voltage (the fixed electrode 41a and the movable electrode 22e can be reduced even while the non-reflective state is maintained for a long time. The first or second Lorentz force current may be always + I and always maintained at the lower intermediate position shown in FIG. 7B. However, if the current for the first or second Lorentz force is maintained at + I in such a long period of time, the power consumption is significantly increased. In contrast, in the present embodiment, during the period of maintaining the non-reflective state, the lower intermediate position shown in FIG. 7B and the lower position shown in FIG. Since the lower middle position shown in b) can be kept to the minimum necessary time, the power consumption can be greatly reduced.

  FIG. 9 is an electric circuit diagram showing the optical switch array 1 and the external control circuit 6 of the optical switch system according to the present embodiment. However, FIG. 9 schematically shows only some of the components of the external control circuit 6. In FIG. 9, elements arranged outside the optical switch array 1 are components of the external control circuit 6.

  The single optical switch shown in FIGS. 3 to 6 includes one capacitor (corresponding to a capacitor formed by the fixed electrode 41a and the movable electrode 22e) and one first coil (first coil) in terms of electrical circuit. 1 Lorentz force current path 22c) and one second coil (corresponding to the second Lorentz force current path 22d). In FIG. 9, the capacitor, the first coil, and the second coil of the optical switch in the m-th row and the n-th column are denoted as Cmn, LAmn, and LBmn, respectively. For example, the capacitor, first coil, and second coil of the optical switch in the upper left (first row, first column) in FIG. 9 are denoted as C11, LA11, and LB11, respectively. In FIG. 9, nine optical switches are arranged in three rows and three columns as described above for the sake of simplicity. However, the number of optical switches is not limited at all, and the principle is the same even when, for example, an optical switch having 100 rows and 100 columns is provided.

  In the optical switch array 1, in order to reduce the number of control lines, common wiring is provided for each row and each column as shown in FIG.

  As shown in FIG. 9, the optical switch array 1 is provided with terminals EBL1 to EBL3, terminals EBR1 to EBR3, terminals S0 to S3, and terminals EA1 to EA3. These terminals are external connection terminals for connection to the external control circuit 6. In the present embodiment, the electrical connection shown in FIG. 9 is realized by the wiring pattern 42a described above. Each of the terminals can be configured, for example, by using a part of the wiring pattern as an electrode pad.

  The fixed electrodes 41a of the capacitors C11, C21, C31 in the first column are electrically connected in common to the terminal S1. The fixed electrodes 41a of the capacitors C12, C22, and C32 in the second row are electrically connected in common to the terminal S2. The fixed electrodes 41a of the capacitors C13, C23, C33 in the third row are electrically connected in common to the terminal S3. Thus, in the present embodiment, the fixed electrode 41a of the microactuator in the column is electrically connected in common for each column.

  The second coils LB11, LB12, LB13 in the first row are connected in series, one end of which is connected to the terminal EBL1 and the other end is connected to the terminal EBR1. Second coils LB21, LB22, and LB23 in the second row are connected in series, and one end thereof is connected to terminal EBL2 and the other end is connected to terminal EBR2. The second coils LB31, LB32, LB33 in the third row are connected in series, and one end thereof is connected to the terminal EBL3 and the other end is connected to the terminal EBR3. The movable electrode 22e of each capacitor Cmn is connected to the left end in FIG. 9 of the second coil LBmn of the same microactuator.

  The second coils LB11, LB12, LB13 in the first row have the same direction of Lorentz force generated in the second coils LB11, LB12, LB13 when a current is passed between the terminals EBR1, EBL1. In addition, they are connected with the same current direction. The same applies to the second coils LB21, LB22, and LB23 in the second row and the second coils LB31, LB32, and LB33 in the third row. In the present embodiment, when current flows in a direction from terminals EBR1 to EBR3 to terminals EBL1 to EBL3 (current in this direction is a positive current), the second current path for Lorentz force of the microactuator. 22d is set so that the second Lorentz force works downward.

  In the present embodiment, wiring is performed so that a current as a control signal for the second coil LBmn is simultaneously supplied for each row in this way.

  The first coils LA11, LA21, LA31 in the first row are connected in series, with one end connected to the terminal EA1 and the other end connected to the terminal S0. The coils LA12, LA22, LA32 in the second row are connected in series, one end of which is connected to the terminal EA2 and the other end is connected to the terminal S0. The third row coils LA13, LA23, LA33 are connected in series, one end of which is connected to the terminal EA3 and the other end is connected to the terminal S0.

  The first coils LA11, LA21, LA31 in the first row have the same direction of the Lorentz force generated in the first coils LA11, LA21, LA31 when a current is passed between the terminals EA1, S0. In addition, they are connected with the same current direction. The same applies to the first coils LA12, LA22, LA32 in the second row and the first coils LA13, LA23, LA33 in the third row. In the present embodiment, when current flows in the direction from terminal EA1, EA2, EA3 toward terminal S0 (current in this direction is a positive current), current path 22c for the first Lorentz force of the microactuator. The Lorentz force is set to work downward.

  In the present embodiment, wiring is performed so that a current as a control signal for the first coil LAmn is simultaneously supplied for each column in this way.

  The optical switch array 1 used in the present embodiment is not equipped with an address circuit, a column selection switch, a row selection switch, or the like as shown in FIG.

  The optical switch array 1 used in the present embodiment can be manufactured by using a semiconductor manufacturing technique such as film formation and patterning, etching, and sacrificial layer formation / removal. The mirror 31 is formed by, for example, forming a recess corresponding to the mirror 31 in the resist, and then growing Au, Ni, or other metal to be the mirror 31 by electrolytic plating, and then removing the resist. Can be formed.

  In this embodiment, as shown in FIG. 9, the changeover switches SWR1 and SWL1, the variable DC voltage source corresponding to the changeover switches SWR and SWL, the variable DC voltage source VH and the variable DC current source IH in FIG. 8, respectively. VH1 and variable DC current source IH1 are provided in common for the optical switch in the first row. A common contact of the changeover switch SWR1 is connected to the terminal EBR1, and a common contact of the changeover switch SWL1 is connected to the terminal EBL1. Reference numeral H1 denotes a current / potential switching supply unit that is configured by the changeover switches SWR1 and SWL1, the variable DC voltage source VH1, and the variable DC current source IH1 as a whole.

  Similarly, the changeover switches SWR2, SWL2, the variable DC voltage source VH2, and the variable DC current source IH2 respectively corresponding to the changeover switches SWR, SWL, the variable DC voltage source VH, and the variable DC current source IH in FIG. The optical switch is provided in common. The common contact of the changeover switch SWR2 is connected to the terminal EBR2, and the common contact of the changeover switch SWL2 is connected to the terminal EBL2. Reference numeral H2 denotes a current / potential switching supply unit that is configured as a whole by the changeover switches SWR2 and SWL2, the variable DC voltage source VH2, and the variable DC current source IH2.

  Similarly, the changeover switches SWR3, SWL3, the variable DC voltage source VH3, and the variable DC current source IH3 corresponding to the changeover switches SWR, SWL, the variable DC voltage source VH, and the variable DC current source IH, respectively, in FIG. The optical switch is provided in common. A common contact of the changeover switch SWR3 is connected to the terminal EBR3, and a common contact of the changeover switch SWL3 is connected to the terminal EBL3. Reference numeral H3 denotes a current / potential switching supply unit that is configured as a whole by the changeover switches SWR3 and SWL3, the variable DC voltage source VH3, and the variable DC current source IH3.

  As shown in FIG. 9, the variable DC voltage source VV1 and the variable DC current source IV1 corresponding to the variable DC voltage source VV and the variable DC current source IV in FIG. 8 are common to the optical switches in the first column. Is provided. Similarly, a variable DC voltage source VV2 and a variable DC current source IV2 respectively corresponding to the variable DC voltage source VV and the variable DC current source IV in FIG. 8 are provided in common for the optical switch in the second column. Yes. Similarly, a variable DC voltage source VV3 and a variable DC current source IV3 corresponding to the variable DC voltage source VV and variable DC current source IV in FIG. 8 are provided in common for the optical switch in the third column. Yes. The terminal S0 is grounded in the external control circuit 6.

  In the present embodiment, the external control circuit 6 uses the above-described elements or the like to cause the current flowing through the terminals EBL1 to EBL3, the potential applied to the terminals EBL1 to EBL3, the current flowing through the terminals EA1 to EA3, and the terminals S1 to S3. By controlling the potential applied to the optical switch, the optical path switching state of each optical switch of the optical switch array 1 is controlled, and the contact continuation stop operation described above is realized. The external control circuit 6 applies a control signal for realizing the optical path switching state indicated by the optical path switching state command signal in response to the optical path switching state command signal to the terminals EBL1 to EBL3 and the terminals EBL1 to EBL3. Are supplied as potentials, currents flowing through the terminals EA1 to EA3, and potentials applied to the terminals S1 to S3, realizing the optical path switching state and realizing the contact continuation stopping operation described above. The specific circuit configuration of the external control circuit 6 is apparent from the operation example described below.

  Next, an operation example of the optical switch system according to the present embodiment will be described. In the following description, the mirror 31 of the optical switch in the m-th row and the n-th column is assumed to be Mmn. For example, the mirror 31 of the optical switch in the upper left (first row, first column) in FIG. 9 is denoted as a mirror M11. In the following description, the position shown in FIG. 7A is “(a) position”, the position shown in FIG. 7B is “(b) position”, and the position shown in FIG. c) “Position”.

  FIG. 10 shows an example of a timing chart of potentials and currents supplied to the corresponding terminals by the variable DC voltage sources VV1 to VV3, the variable DC current sources IV1 to IV3 and the current / potential switching supply units H1 to H3 of the external control circuit 6, respectively. Is shown.

  At time t1, which is the initial state when the power is turned on, all the mirrors Mmn are in the position (a). Next, at time t2, the potential + V is supplied from the variable DC voltage sources VV1 to VV3, and the current / potential switching supply units H1 to H3 are switched to the variable DC voltage sources VH1 to VH3 to supply the potential -V.

  Next, at time t3, a positive current + I is supplied from each of the variable DC current sources IV1 to IV3. At this time, all the mirrors Mmn move to the position (c). Subsequently, at time t4, the currents IV1 to IV3 are returned to zero. At this time, since the electrostatic force acts between the movable electrode 22e and the fixed electrode 41a, all the mirrors Mmn are kept in the position (c). As after time t4, the potential + V is applied by the variable DC voltage sources VV1 to VV3, the potential -V is applied by the current / potential switching supply units H1 to H3, and the variable DC current sources IV1 to IV3 are applied. Is a steady state of the optical switch system according to the present embodiment, and a series of operations (a series of optical path switching operations and a series of contact continuation stop operations) are temporarily terminated in this state, It is customary to proceed to the next operation.

  Next, a procedure for moving only one mirror among the mirrors in each row (and each column) from the state where all the mirrors Mmn are in the (c) position to the (a) position will be described. At time t6, the potential applied by the variable DC voltage source VV1 and the potential applied to the current / potential switching supply unit H1 are set to zero. Then, there is no electrostatic force between the movable electrode 22e and the fixed electrode 41a in the mirror M11, the movable plate 12 moves upward by the spring force of the leaf spring portion of the movable plate 12, and the mirror M11 is moved to the position (a). It becomes. At time t7, the potential + V is applied again by the variable DC voltage source VV1, and the potential -V is applied by the current / potential switching supply unit H1. At this time, since the mirror M11 is in the position (a), the mirror M11 does not move. Next, from time t8 to t11, similar to time t6 to t8, a release operation (an operation to move the mirror from the (c) position to the (a) position) is performed on the mirror M22 and the mirror M33. Through these series of operations, the mirrors M11, M22, and M33 are in the (a) position and are in the reflecting state, and the other mirrors are in the (c) position and remain in the non-reflecting state.

  Next, a mirror replacement operation, that is, an optical path switching operation will be described with reference to FIG. Here, at time t21, the state is the same as after time t11 in FIG. 10 (that is, a steady state in which the mirrors M11, M22, and M33 are at the position (a) and the other mirrors are at the position (c)). And At time t22, a positive current + I is supplied from the variable DC current source IV1. As a result, all the movable plates 12 in the (a) position in the first row move to the (c) position. Eventually, since the mirror at the position (a) is only the mirror M11, only the mirror M11 moves to the position (c). Thereafter, at time t23, the current of the variable DC current source IV1 is set to zero. Next, at time t24, a positive current + I is supplied from the variable DC current source IV2. As a result, all the movable plates 12 in the (a) position in the second row move to the (c) position. Eventually, only M22 in the position (a) moves to the position (c). Thereafter, at time t25, the current of the variable DC current source IV2 is set to zero. Next, at time t26, the mirror M12 is moved from the (c) position to the (a) position. This procedure is the same as the time t8 in FIG. The procedure at time t27 is the same as that at time t9 in FIG. Finally, at time t28, the mirror M21 is moved from the (c) position to the (a) position, and the replacement is completed. Then, it returns to a steady state at time t29.

  From the above description of the operation with reference to FIGS. 10 and 11, the optical switch system according to the present embodiment can realize an arbitrary optical path switching state indicated by the optical path switching state command signal in response to the optical path switching state command signal. ,Recognize.

  Next, the contact continuation stop operation will be described with reference to FIG. Here, at time t41, the state is the same as that after time t11 in FIG. 10 (that is, a steady state in which the mirrors M11, M22, and M33 are in the (a) position and the other mirrors are in the (c) position). And Here, an example in which the contact continuation stop operation of the mirror M21 is performed from this state will be described.

  First, at time t42, the potential applied by the variable DC voltage source VV1 is set to zero. Next, at time t43, the current / potential switching supply unit H1 is switched to the variable DC current source IH1 side. At this time, the voltage between the movable electrode 22e of the optical switch of the mirror M11 and the fixed electrode 41a becomes zero, but since the mirror M11 is originally in the position (a), the position does not change. Further, since the voltage between the movable electrode 22e of the optical switch of the mirrors M12 and M13 and the fixed electrode 41a is V (= + V-0), the position of the mirrors M12 and M13 is (c) due to the electrostatic force thereby. The position remains unchanged.

  Next, the current of the variable DC current source IV1 of the current / potential switching supply unit H1 is gradually changed from time t44 to reach the positive current + I at time t45. At the same time, the current of the variable DC current source IV1 is changed to the negative current -I at the time t45 so that the time change and the magnitude of the current are substantially the same. In this process, since the mirror M11 is in the position (a), the position should change when a current is applied, but the variable DC current source IV1 and the current / potential switching supply unit H1 just cancel each other. Since the current is applied to the two, the Lorentz forces of both cancel each other, so that only the amount of current flowing changes in the mirror M11 while maintaining the position (a). Since the mirrors M12, M13, M21, and M31 are at the position (c), the current flowing in this process changes, but the position does not change. That is, the movable plate 12 of the optical switch of the mirrors M12 and M13 receives an upward Lorentz force due to the positive current from the current / potential switching supply unit H1, but the movable electrode 22e of the optical switch and the fixed electrode 41a Since the voltage between them is V (= + V-0), the positions of the mirrors M12 and M13 remain unchanged at the position (c) due to the electrostatic force. Further, since the movable plate 12 of the optical switch of the mirrors M21 and M31 receives a downward Lorentz force due to the negative current from the variable DC current source IV1, the positions of the mirrors M21 and M31 remain unchanged at the position (c).

  Next, at time t45, the potential of the current / potential switching supply unit H2 is set to zero. At this time, the positive current + I from the variable DC current source IV1 flows through the optical switch of the mirror M21, and the voltage between the movable electrode 22e and the fixed electrode 41a of the optical switch is zero. As already described, the mirror M21 is in the (b) position. At this time, since a predetermined space is provided between the fixed portion of the mirror M21 and the movable plate 12, sticking due to the movable plate 12 being in contact with the fixed portion for a long time is prevented. Even if the potential of the current / potential switching supply unit H2 is set to zero, the position of the mirror M22 remains unchanged at the position (a), and the mirror M23 remains unchanged at the position (c). The reason is that in the case of the mirror M22, the voltage V is applied between the movable electrode 22e of the optical switch of the mirror M22 and the fixed electrode 41a, but the mirror M22 is at the position (a), so This is because the distance is sufficiently long so that almost no electrostatic force is generated, and the first and second currents for the Lorentz force do not flow through the optical switch, and the Lorentz force is not applied. In the case of the mirror M23, both the first and second currents for Lorentz force do not flow through the optical switch and no Lorentz force is applied, and the mirror M23 is at the position (c), and the mirror M22 This is because the voltage V is applied between the movable electrode 22e and the fixed electrode 41a of the optical switch, and a sufficiently large electrostatic force acts between the two.

  Next, at time t46, the potential of the current / potential switching supply unit H2 is set to −V again. As a result, the mirror M21 returns to the position (c) again. At times t47, t48, and t49, the operations just opposite to those at times t42, t43, and t44 are performed, the system returns to the steady state, and the series of operations ends.

  From the above description of the contact continuation stop operation with reference to FIG. 12, for any mirror located at the position (c) in the steady state in any optical path switching state, the position of the other mirror is not changed. It can be seen that the contact continuation stop operation can be performed.

  In the present embodiment, under the control of the external control circuit 6, the contact continuation stop operation of each optical switch is performed at a predetermined appropriate timing so that the state of the position (c) of each optical switch does not continue for a predetermined time or longer. It is to be done in.

  According to the present embodiment, since the contact continuation stopping operation is performed in this way, it is possible to shorten the continuation period in which the mirror 31 and the movable plate 12 are located at the lower position shown in FIG. . Therefore, it becomes difficult for the movable plate 12 to stick to the fixed portion, and when the movable plate 12 returns from the position shown in FIG. 7C to the position shown in FIG. It becomes difficult to cause an operation delay. Further, according to the present embodiment, as described above, the lower intermediate position shown in FIG. 7B and the lower position shown in FIG. As a result, the lower intermediate position shown in FIG. 7B can be kept at a necessary minimum time, and thus power consumption can be greatly reduced.

  Furthermore, according to the present embodiment, as shown in FIG. 9 described above, common wiring is provided for each row and column, so that the number of wirings to be drawn outside can be reduced without mounting an address circuit or the like. it can. In spite of the common wiring, the movable plate 12 is provided with two current paths 22c and 22d for Lorentz force as two driving force generators for generating a driving force other than the electrostatic force. Therefore, in the operation of stopping the contact of a certain mirror 31, the position of another mirror is not changed, and an appropriate optical path switching state can be maintained.

  [Second Embodiment]

  FIG. 13 shows the pattern shape of the Al film 22 when the movable plate 12 of one optical switch of the optical switch array 101 used in the optical switch system according to the second embodiment of the present invention is viewed from above. FIG. 5 corresponds to FIG. 13, elements that are the same as or correspond to those in FIG. 5 are given the same reference numerals, and redundant descriptions thereof are omitted.

  FIG. 14 is an electric circuit diagram showing the optical switch array 101 and the external control circuit 106 of the optical switch system according to the present embodiment, and corresponds to FIG. 14, elements that are the same as or correspond to those in FIG. 9 are given the same reference numerals, and redundant descriptions thereof are omitted.

  This embodiment is different from the first embodiment only in the points described below.

  In the first embodiment, in each optical switch, the pattern 22b is used not only as the wiring of the Lorentz force current path 22c but also as the wiring of the movable electrode 22e. As shown in FIG. 13, in each optical switch, the pattern 22b is used only as the wiring of the Lorentz force current path 22c, and the pattern 22f is added as the wiring of the movable electrode 22e. The pattern 22 f is also a pattern in the Al film 22. Accordingly, in the present embodiment, a leg portion 12e for connecting the pattern 22e to the substrate 11 side is added.

  In the present embodiment, the wiring of the Lorentz force current path 22c and the wiring of the movable electrode 22e are separated, and the wiring of the optical switch array 101 and the configuration of the external control circuit 106 are shown in FIG. Has also changed.

  In the optical switch array 101, as shown in FIG. 14, the terminals EBL1 to EBL3 in FIG. 9 are removed, and the left ends of the second coils LB11, LB21, LB31 in the figure are connected to the terminal S0. Further, in the optical switch array 101, as shown in FIG. 14, instead of the terminals EBR1 to EBR3 in FIG. 9, terminals EBV1 to EBV3 and terminals EBI1 to EBI3 are provided. The movable electrode 22e of each capacitor Cmn is not connected to the second coil LBmn of the same microactuator.

  The capacitors C11, C12, C13 in the first row are electrically connected in common to the terminal EBV1. The capacitors C21, C22, C23 in the second row are electrically connected in common to the terminal EBV2. The capacitors C31, C32, C33 in the third row are electrically connected in common to the terminal EBV3.

  The right end in FIG. 14 of the coil LB13 is electrically connected to the terminal EBI1, the right end in FIG. 14 of the coil LB23 is electrically connected to the terminal EBI2, and the right end in FIG. 14 of the coil LB33 is electrically connected to the terminal EBI3. It is connected to the.

  In the external control circuit 106, the selector switches SWR1 to SWR3 and SWL1 to SWL3 in FIG. 9 are removed. One ends of variable DC voltage sources VH1 to VH3 are connected to terminals EBV1 to EBV3, respectively. One ends of variable DC current sources IH1 to IH3 are connected to terminals EBI1 to EBI3, respectively.

  Also according to the present embodiment, substantially the same operation as that described with reference to FIGS. 10 to 12 with respect to the first embodiment is possible. Therefore, the same advantages as those of the first embodiment can be obtained by this embodiment.

  Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments.

  For example, each of the embodiments described above is an example of an optical switch system using an optical switch array in which a plurality of optical switches are two-dimensionally arranged. However, the present invention is an optical switch using only one optical switch. It may be a system. In this case, the control unit that controls the operation of the microactuator of the optical switch may be configured to control the operation as described with reference to FIGS. 7 and 8.

  Moreover, although the said embodiment was an example which applied the microactuator apparatus by this invention to the optical switch system, it is not limited to the use.

  Furthermore, in the above embodiment, two Lorentz forces are used as the two driving forces as the driving force other than the electrostatic force, but the present invention is not limited to this, and the driving force other than the electrostatic force is used. As the two driving forces, various driving forces can be used. For example, instead of driving with Lorentz force, driving may be performed using a piezoelectric element.

1 is a schematic configuration diagram showing an optical switch system according to a first embodiment of the present invention. FIG. 2 is a schematic plan view schematically showing the optical switch array in FIG. 1. FIG. 2 is a schematic plan view schematically showing one optical switch as a unit element of the optical switch array in FIG. 1. FIG. 4 is a schematic cross-sectional view along the line A-A ′ in FIG. 3. It is a figure which shows the pattern shape of Al film when the movable plate in FIG. 3 is seen from the top. FIG. 6 is a schematic cross-sectional view of a cross section taken along line B-B ′ in FIGS. 3 and 5 when viewed from the + Y side in the −Y axis direction. It is a schematic side view which shows typically each position where the movable plate of one optical switch and the mirror provided in this are hold | maintained. It is explanatory drawing which shows the example of the control signal given to one optical switch. FIG. 2 is an electric circuit diagram showing an optical switch array and an external control circuit in FIG. 1. 2 is a timing chart showing an example of the operation of the optical switch system shown in FIG. 1. 6 is a timing chart showing another example of the operation of the optical switch system shown in FIG. 1. 6 is a timing chart showing still another example of the operation of the optical switch system shown in FIG. 1. It is a figure which shows the pattern shape of Al film when the movable plate of one optical switch of the optical switch array used with the optical switch system by the 2nd Embodiment of this invention is seen from the top. It is an electric circuit diagram which shows the optical switch array and external control circuit of the optical switch system by the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Optical switch array 2 Optical fiber for optical inputs 3, 4 Optical fiber for optical outputs 5 Magnet 6 External control circuit 11 Substrate 12 Movable plate 22c First current path for Lorentz force 22d Second current path for Lorentz force 22e Movable electrode 31 mirror 41a fixed electrode

Claims (12)

A fixed portion, and a movable portion provided so as to be movable with respect to the fixed portion between a first position away from the fixed portion and a second position abutting on the fixed portion,
The fixed part has a first electrode part,
The movable part is provided so as to generate a return force to return to the first position,
The movable portion includes a second electrode portion that can generate an electrostatic force with the first electrode portion due to a voltage between the first electrode portion and the first electrode portion. A first driving force generator capable of generating a driving force other than an electrostatic force in a direction toward the second position, a direction toward the second position from the first position according to a control signal, and the opposite direction And a second driving force generator capable of generating a driving force other than an electrostatic force. The first driving force generation unit is a first current path that is arranged in a magnetic field and generates Lorentz force by energization,
2. The microactuator according to claim 1, wherein the second driving force generation unit is a second current path that is arranged in a magnetic field and generates a Lorentz force when energized. 3.   3. The microactuator according to claim 2, wherein one of the first and second current paths is electrically connected to the second electrode. A microactuator device comprising the microactuator according to any one of claims 1 to 3 and a control unit that controls the operation of the microactuator,
The control unit is configured so that the movable unit moves from the second position to the first position and the second position so that the movable unit is not continuously located at the second position for a predetermined time or more. The microactuator is controlled so as to perform an operation of returning to the second position after being positioned at a third position between the fixed position and the third position. Actuator device.   The said control part applies a voltage so that an electrostatic force may arise between the said 1st and 2nd electrode part, when hold | maintaining the said movable part in the said 2nd position. The microactuator device described.   The third position is a position where the return force and the driving force in the direction from the first position toward the second position by the first driving force generator or the second driving force generator are balanced. The microactuator device according to claim 4 or 5, wherein Comprising a plurality of microactuators arranged in two dimensions,
Each of the plurality of microactuators is the microactuator according to any one of claims 1 to 3,
For each row (or each column), wiring is performed so that a control signal for the first driving force generation unit of the microactuator of the row (or the column) is supplied simultaneously,
A microactuator array, wherein wiring is performed so that a control signal for the second driving force generation unit of the microactuator in the column (or row) is simultaneously supplied for each column (or row). A microactuator device comprising: the microactuator array according to claim 7; and a control unit that controls operations of the plurality of microactuators.
The control unit is configured so that the movable part is moved from the second position to the first position and the second position so that the movable part of each microactuator is not continuously located at the second position for a predetermined time or more. The plurality of microactuators are controlled to perform an operation of returning to the second position after being positioned at a third position between the second position and a third position away from the fixed portion. A microactuator device characterized in that:   The controller applies a voltage so that an electrostatic force is generated between the first and second electrode portions of the microactuator when the movable portion of each microactuator is held at the second position. The microactuator device according to claim 8.   The third position of each microactuator is the first position of the microactuator from the first position of the microactuator and the first driving force generation unit or the second driving force generation unit of the microactuator. 10. The microactuator device according to claim 8, wherein the microactuator device is in a position where a driving force in a direction toward the position 2 is balanced.   An optical switch system comprising the microactuator device according to any one of claims 4 to 6 and 8 to 10, and a mirror provided on the movable portion. When the movable part is located at the first position, the mirror is in one of a reflective state and a non-reflective state,
The light according to claim 11, wherein when the movable part is located at the second position and the third position, the mirror is in the other state of a reflective state and a non-reflective state. Switch system.

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