JP2005238346A - Actuator and optical device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an actuator and an optical device for accurately determining a position of a movable plate in a state of applying no stress to the movable plate by a plate driving part. <P>SOLUTION: This actuator has the movable plate 2 displaceable by deflecting a flexible plate support part 1 having one end connected to a fixing part 10, the plate driving part 3 for driving the movable plate 2, a movable latch part 5 displaceable by deflecting a flexible latch support part 4 having one end connected to the fixing part 10, and a latch driving part 6 for driving a movable latch part 5. When the plate driving part 3 does not apply stress to the movable plate 2, and when the latch driving part 6 does not apply stress to the movable latch part 5, the movable latch part 5 holds a position of the movable plate by contacting with the movable plate, and when the plate driving part 3 displaces the movable plate 2, the latch driving part 6 displaces the movable latch part 5 in the direction for separating from the movable plate 2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an actuator and an optical device, and more particularly to an actuator and an optical device based on a microelectromechanical system.

  An optical switch which is one of optical devices is mainly classified into three types: a mechanical type, a waveguide type, and a micro-electro-mechanical system (MEMS) type. Among these, in the MEMS type, the optical waveguide, the mirror, and the driving mechanism can be integrally formed on one silicon chip by using a micromachining technology formed by a semiconductor process. Moreover, the core diameter of the optical fiber used for optical communication is as small as 9 μm, and the MEMS type has been expected to be applied to an optical switch in terms of size and cost.

  An attractive force due to static electricity has been used as a driving principle of the MEMS mechanism. It is roughly classified into a gap closing method that uses a surface-direction attractive force between two electrodes and a comb method that uses an attractive force in a plane-parallel direction of the comb-shaped electrodes arranged opposite to each other.

Conventionally, a fixed electrode and a movable electrode are arranged opposite to each other, and the movable electrode is displaced with respect to the movable electrode in an actuator that displaces the movable electrode by an electrostatic attractive force generated between both electrodes and the optical switch using the actuator A technique is known in which a movable electrode is held in a displaced state even after the electrostatic attraction is released using a latch member that is fitted in a state (see, for example, Patent Documents 1 and 2).
JP 2003-241117 A JP 2003-279864 A

  However, in the techniques disclosed in Patent Documents 1 and 2, the latch member is fitted in the displaced state with respect to the movable electrode, but the movable electrode is not displaced, that is, in a state where no electrostatic attractive force is applied. The position of cannot be held. Usually, the movable electrode is fixed via a flexible support material, and can be displaced by bending the support material. Therefore, the position of the movable electrode in a state where the support member is not bent cannot be accurately determined, and is easily displaced by external vibration or the like.

  The first feature of the present invention is that a flexible plate support part having one end connected to a fixed part that supports the entire actuator, and a displacement that is connected to the other end of the plate support part by bending the plate support part. A movable plate, a plate driving unit that applies displacement to the movable plate, a flexible latch support unit having one end connected to the fixed unit, and a latch connected to the other end of the latch support unit. An actuator having a movable latch part that can be displaced by bending of the support part, and a latch drive part that applies displacement to the movable latch part to displace it, and the plate drive part applies stress to the movable plate. When the latch drive unit does not apply stress to the movable latch unit, the movable latch unit contacts the movable plate to hold the position of the movable plate, and the plate drive unit When displacing the over preparative latch driving portion is summarized in that to displace in a direction away moving latch portion from the movable plate.

  A second feature of the present invention is an optical switch including the actuator according to the first feature, a mirror connected to the movable plate, and a pair of optical waveguides that intersect or face each other in the vicinity of the mirror. And

  According to the present invention, it is possible to provide an actuator and an optical device that accurately determine the position of the movable plate in a state where the plate driving unit does not apply stress to the movable plate.

  Embodiments of the present invention will be described below with reference to the drawings. In the description of the drawings, the same or similar parts are denoted by the same or similar reference numerals.

(First embodiment)
As shown in FIG. 1, the actuator according to the first embodiment of the present invention includes a fixed portion 10 that supports the entire actuator, a flexible plate support portion 1 having one end connected to the fixed portion 10, and A movable plate 2 connected to the other end of the plate support portion 1 and displaceable by bending of the plate support portion 1, a plate driving portion 3 for applying displacement to the movable plate 2, and a fixed portion 10. A flexible latch support portion 4 connected at one end, a movable latch portion 5 connected to the other end of the latch support portion 4 and displaceable by bending the latch support portion 4, and a movable latch portion 5 A latch driving unit 6 that is displaced by applying stress, an electrical interlocking line 7 that electrically connects the plate driving unit 3 and the latch driving unit 6, and a latch mechanism 8 that holds the movable plate 2 in a displaced state. Have The movable plate 2 has a fitting member 9 on its side surface, and the fitting member 9 is fitted to the distal end portion of the movable latch portion 5.

  When the plate driving unit 3 does not apply stress to the movable plate 2 and the latch driving unit 6 does not apply stress to the movable latch unit 5, the tip of the movable latch unit 5 is a fitting member of the movable plate 2. The position of the movable plate 2 is maintained by contact (fitting) with 9.

  The movable plate 2 can be displaced toward the plate driving unit 3 by bending the plate support unit 1. The plate driving unit 3 applies stress to the movable plate 2 and displaces it to the plate driving unit 3 side. If the plate driving unit 3 does not apply stress to the movable plate 2, it returns to the original state by the elastic restoring force of the plate support unit 1. Note that the latch mechanism 8 holds the movable plate 2 in a state of being displaced toward the plate driving unit 3. Moreover, in order to return to the original state shown in FIG. 1 only by the elastic restoring force of the plate support part 1 and to fit the front end of the movable latch part 5 and the fitting member 9, the inclination of the outside of the fitting member 9 is increased. It is desirable to loosen. Thus, the latch can be applied in the original state shown in FIG. 1 only by the elastic restoring force of the plate support portion 1.

  When the plate driving unit 3 displaces the movable plate 2, the latch driving unit 6 displaces the movable latch unit 5 in a direction away from the movable plate 2. Specifically, in the state shown in FIG. 1, since the tip of the movable latch portion 5 is fitted with the fitting member 9 of the movable plate 2, the fitting becomes an obstacle, and the movable plate 2 is displaced. I can't. When the movable plate 2 is displaced, it is necessary to release the fitting between the tip of the movable latch portion 5 and the fitting member 9. Therefore, the plate driving unit 3 and the latch driving unit 6 are electrically interlocked by the electric interlocking line 7 so that the plate driving unit 3 drives the movable plate 2 and the latch driving unit 6 moves the movable latch unit 5. The operation of driving away from the plate 2 is linked.

  As described above, conventionally, the movable plate 2 is stable because no structural stress is applied at the initial formation position, but its position easily fluctuates due to disturbance and is unstable. I can say that. However, as shown in FIG. 1, by newly providing a latch mechanism at the initial formation position of the movable plate 2, the positional accuracy at the initial formation position of the movable plate 2 is improved, and against disturbances such as vibration and impact. Can also be prevented from being easily displaced.

  Further, by electrically interlocking the plate driving unit 3 and the latch driving unit 6, electronic control is not necessary, and the electric circuit can be simplified.

  The movable plate 2 and the movable latch portion 5 are suspended from four flexible support portions 1 and 4, respectively. The fixing unit 10 is a basic component of the MEMS structure. In FIG. 1, four support portions 1 and 4 are described, but one support portion may be provided for each of the upper and lower portions, and a folded structure may be used. In the case of the folded structure, the elongation of the support portions 1 and 4 when bent can be relaxed. By the support parts 1 and 4, the movable plate 2 and the movable latch part 5 can each move linearly (one-dimensionally).

  The actuator shown in FIG. 1 has a two-layer structure composed of an upper layer and a lower layer. All the components of the actuator shown in FIG. 1 are arranged in the upper layer. Among the constituent elements of the actuator, the fixed portion 10 is connected to a substrate disposed in a lower layer that is overlapped with an insulating film below the upper layer. The components excluding the fixing part 10 are arranged so as to overlap above the substrate, but the insulating film is not arranged. Therefore, the support portions 1 and 4 whose one ends are connected to the fixed portion 10 can freely bend (displace) with respect to the substrate, and similarly, the movable element connected to the support portions 1 and 4 is the substrate. Can move against. An actuator having such a two-layer structure can be easily formed using a semiconductor process. That is, a two-layer structure can be easily realized by using an anisotropic etching method such as a photolithography method, a reactive ion etching method (RIE method), and a wet etching method of an insulating film (oxide film).

(Second Embodiment)
As shown in FIG. 2, the actuator according to the second embodiment of the present invention includes a fixing portion 10 that supports the entire actuator, a flexible plate support portion 1 having one end connected to the fixing portion 10, and A movable plate 2 that is connected to the other end of the plate support portion 1 and can be displaced by bending the plate support portion 1, and first and second plate drive portions 3 a that are displaced by applying stress to the movable plate 2. 3b, a flexible latch support portion 4 having one end connected to the fixed portion 10, and a movable latch portion 5 connected to the other end of the latch support portion 4 and displaceable by bending the latch support portion 4. And first and second latch driving units 6a and 6b for applying displacement to the movable latch unit 5, and between the first plate driving unit 3a and the first latch driving unit 6a and the second plate. Drive unit 3b and second latch First and second electrical interlocking lines 7a and 7b that electrically connect the moving parts 6b, respectively, and first and second latch mechanisms 8a and 8b that hold the movable plate 2 in a displaced state. . The movable plate 2 has a fitting member 9 on its side surface, and the fitting member 9 is fitted to the distal end portion of the movable latch portion 5.

  The first and second plate driving units 3 a and 3 b do not apply stress to the movable plate 2, and the first and second latch driving units 6 a and 6 b do not apply stress to the movable latch unit 5. Sometimes, the tip of the movable latch portion 5 contacts the fitting member 9 of the movable plate 2 to hold the position of the movable plate 2.

  The movable plate 2 can be displaced to the side of the first plate driving unit 3a (upper side) and the side of the second plate driving unit 3b (lower side) by bending the plate support unit 1. The first plate driving unit 3a applies stress to the movable plate 2 to displace it upward. The second plate driving unit 3b applies stress to the movable plate 2 and displaces it downward. The movable plate 2 returns to the original state by the elastic restoring force of the plate support 1 if the first and second plate driving units 3a and 3b do not apply stress to the movable plate 2. Note that the first latch mechanism 8a holds the movable plate 2 in a state of being displaced upward. The second latch mechanism 8b holds the movable plate 2 in a state of being displaced downward.

  When the first plate driving unit 3 a displaces the movable plate 2, the first latch driving unit 6 a displaces the movable latch unit 5 in a direction away from the movable plate 2. When the second plate driving unit 3 b displaces the movable plate 2, the second latch driving unit 6 b displaces the movable latch unit 5 in a direction away from the movable plate 2. Specifically, in the state shown in FIG. 2, the tip of the movable latch portion 5 is fitted with the fitting member 9 of the movable plate 2, so that the fitting becomes an obstacle and the movable plate 2 is displaced. I can't. When the movable plate 2 is displaced, it is necessary to release the fitting between the tip of the movable latch portion 5 and the fitting member 9. Therefore, the first plate driving unit 3a electrically operates the first plate driving unit 3a and the first latch driving unit 6a by the first electric interlocking line 7a, and the first plate driving unit 3a drives the movable plate 2. (Operation to move the movable plate 2 from the lower position or the center position to the upper position) and the operation in which the first latch driving unit 6a drives the movable latch unit 5 away from the movable plate 2 are linked. Similarly, the second plate driving unit 3b and the second latch driving unit 6b are electrically interlocked by the second electrical interlocking line 7b, and the second plate driving unit 3b drives the movable plate 2. The operation (the operation of displacing the movable plate 2 from the upper position or the center position to the lower position) and the operation of the second latch driving unit 6b driving the movable latch unit 5 in the direction away from the movable plate 2 are linked.

  As described above, as shown in FIG. 2, by newly providing a latch mechanism at the initial formation position of the movable plate 2, the positional accuracy at the initial formation position of the movable plate 2 is improved, and vibration, impact, etc. It is possible to prevent displacement easily even against disturbance.

  Further, by electrically interlocking the first plate driving unit 3a and the first latch driving unit 6a, electronic control is not necessary, and the electric circuit can be simplified. Similarly, by electrically interlocking the second plate driving unit 3b and the second latch driving unit 6b, electronic control is not necessary, and the electric circuit can be simplified.

(First embodiment)
With reference to FIG. 3, a first embodiment of the actuator having the basic structure of the actuator shown in FIGS. 1 and 2 will be described.

As shown in FIG. 3, the actuator according to the first embodiment is connected to a fixed portion 10, a flexible plate support portion 1 having one end connected to the fixed portion 10, and the other end of the plate support portion 1. The movable plate 2 is displaceable by bending the plate support portion 1, the first and second plate driving portions 3 a and 3 b are displaced by applying stress to the movable plate 2, and the fixed portion 10 has one end. Are connected to the other end of the latch support, and the first and second movable latches 5a and 5b can be displaced by bending the latch support. The first and second latch driving portions 6a and 6b for applying stress to the first and second movable latch portions 5a and 5b and displacing the first and second movable latch portions 5a and 5b, the first and second plate driving portions 3a and 3b, and the first Between the first and second latch driving units 6a and 6b Re has a first electrical interlocking lines 7a _1, 7a ₂ and second electrical interlock line 7b _1, and 7b ₂ that electrically connects. The movable plate 2 has first and second fitting members 9a, 9b on its side surfaces, and the first and second fitting members 9a, 9b are first and second movable latch portions 5a, 5b. It is separated from the tip portion by a “predetermined gap”. FIG. 3 shows a state immediately after the manufacture of the actuator. By performing an “irreversible operation” from this state, the first and second fitting members 9a and 9b can move to the first and second movable members. The latch portions 5a and 5b are respectively fitted with the tip portions. The “predetermined gap” and “irreversible operation” will be described later with reference to FIGS. 4 (a) and 4 (b).

  In the first embodiment, the first and second plate driving units 3a and 3b are comb-type actuators that use an attractive force in a direction parallel to the electrode surfaces of the comb-shaped electrodes disposed opposite to each other. On the other hand, the first and second latch driving units 6a and 6b are gap closing type actuators that utilize an attractive force in a direction perpendicular to the electrode surfaces of the comb-shaped electrodes disposed in opposition to each other. That is, the first and second latch driving units 6a and 6b include a fixed electrode connected to the fixed unit 10 and a movable electrode that can be freely displaced, and the electrode surfaces of the fixed electrode and the movable electrode are arranged in the driving direction. It is arranged vertically. In any type of actuator, an electrostatic attractive force (driving force) is generated by applying a potential difference between opposing comb electrodes.

  The comb type actuator (1) has a long driving stroke, but the resistance to the stress in the direction perpendicular to the driving direction of the flexible support becomes low. (2) It has a long shape in the direction perpendicular to the driving direction and requires a large space. Therefore, it is suitable for the first and second plate driving units 3a and 3b, which are movable plate actuators that require a relatively long driving stroke.

On the other hand, the gap closing type actuator (1) has a short operating stroke, but can be easily multi-staged to obtain a high output. (2) It has a long shape in the driving direction. (3) Since the flexible support is relatively short and can be placed at a distance, the resistance to lateral stress is high. Therefore, it is suitable for the first and second latch driving units 6a and 6b, which are latch release actuators. Further, the gap closing type actuator can charge the left and right electrostatic driving units independently with respect to the driving direction. Accordingly, the first electrical interlocking line 7a ₁ is connected to the first latch driving part 6a ₁ , the first electrical interlocking line 7a ₂ is connected to the first latch driving part 6a ₂ , and the first latch The driving units 6a ₁ and 6a ₂ can independently drive the first movable latch unit 5a. Similarly, the second electrical interlocking line 7b ₁ is connected to the second latch driver 6b ₁ , the second electrical interlocking line 7b ₂ is connected to the _second latch driver 6b ₂ , and the second The latch driving units 6b ₁ and 6b ₂ can independently drive the second movable latch unit 5b.

  3 has fitting members 9a and 9b on both side surfaces of the movable plate 2, respectively, and has a bilaterally symmetric configuration. However, when it is not necessary to consider the balance of force, only one of them is used. It does not matter. In this case, each of the movable latch portions 5a and 5b and the latch drive portions 6a and 6b is only one.

  Further, the combination of the comb method and the gap closing method is not limited to the example of the actuator shown in FIG. 3, and other combinations may be used.

  Next, referring to FIGS. 4A and 4B, the state (initial state) of the second movable latch portion 5b immediately after the initial formation and the second movable latch after performing the irreversible operation. The state (fitting state) of the part 5b will be described. The first movable latch portion 5a is the same as the second movable latch portion 5b.

  As shown in FIG. 4A, the second movable latch portion 5b includes a latch member 13 that comes into contact with the second fitting member 9b, a columnar member 14 connected to the latch member 13, and a columnar member 14. A tapered latch claw 15 disposed on the side surface, a flexible return preventing member 16, a frame 18, and the support portion 4 are provided. The second movable latch portion 5b is connected to the frame 18 via the latch support portion 4 and can be displaced by the latch support portion 4 being bent. The columnar member 14 is suspended at four places (at least two places) by the latch support portion 4. The latch claw 15 may have a triangular shape or a cone shape.

  In a MEMS structure manufactured through a series of semiconductor manufacturing processes, a plurality of members are not in contact with each other immediately after the manufacturing, and there is a predetermined structure determined by the requirements of the semiconductor manufacturing process between adjacent members. A gap (for example, about 5 μm) is always formed. Therefore, the actuator of FIG. 1 manufactured through a series of semiconductor manufacturing processes is no exception, and immediately after the manufacture, the predetermined gap is formed between the latch member 13 and the second fitting member 9b. ing. Two return prevention members 16 are arranged along the latch claw 15, and the predetermined gap is formed between the return prevention member 16 and the latch claw 15.

  As shown in FIG. 4B, the latch support 4 is bent and the latch member 13, the columnar member 14 and the latch claw 15 are displaced toward the second fitting member 9b. This displacement operation is performed until the second fitting member 9b and the latch member 13 come into contact with each other. And when the return prevention member 16 engages with the latch claw 15, the state where the second fitting member 9b and the latch member 13 are in contact with each other is irreversibly held. That is, once the irreversible operation is performed from the initial state of FIG. 4A to the fitted state of FIG. 4B, the initial state of FIG. There is nothing. By performing an irreversible operation from the initial state shown in FIG. 4A to the fitted state shown in FIG. 4B, the first and second plate driving units 3a and 3b apply stress to the movable plate 2. In addition, when the first and second latch driving units 6a, 6b are not applying stress to the first and second movable latch units 5a, 5b, the first and second movable latch units 5a, 5b can hold the position of the movable plate 2 in contact with the movable plate 2. This irreversible operation can be performed manually or using some drive means. The displacement length of the second movable latch portion 5b is such that the predetermined gap is filled and the latch support portion necessary for the latch member 13 to pressurize the second fitting member 9b with an appropriate pressure. This is the total length of the four deflection lengths.

  As shown in FIG. 5, the first and second plate driving units 3a and 3b do not apply stress to the movable plate 2, and the first and second latch driving units 6a and 6b are movable latch units 5a, When no stress is applied to 5b (uncharged state), the tips of the first and second movable latch portions 5a and 5b come into contact with the first and second fitting members 9, respectively, and the movable plate 2 position (center position) is held. Since the tips of the first and second movable latch portions 5a and 5b pressurize the first and second fitting members 9 with an appropriate pressure by the elastic reaction force caused by the bending of the latch support portion 4, the movable plate 2 is accurately positioned at the center position.

  The movable plate 2 can be displaced to the side of the first plate driving unit 3a (upper side) and the side of the second plate driving unit 3b (lower side) by bending the plate support unit 1. The first plate driving unit 3a applies stress to the movable plate 2 to displace it upward. The second plate driving unit 3b applies stress to the movable plate 2 and displaces it downward. The movable plate 2 returns to the original state by the elastic restoring force of the plate support 1 if the first and second plate driving units 3a and 3b do not apply stress to the movable plate 2.

As shown in FIG. 6, when the second plate driving unit 3b displaces the movable plate 2, the first and second latch driving units 6a ₂ and 6b ₂ are used as the first and second movable latch units 5a and 5b. Are displaced in the direction away from the movable plate 2. Specifically, in the state shown in FIG. 5, the tips of the first and second movable latch portions 5a and 5b are fitted with the first and second fitting members 9a and 9b of the movable plate 2, respectively. Therefore, the fitting becomes an obstacle, and the movable plate 2 cannot be displaced. When the movable plate 2 is displaced, it is necessary to release the fitting between the tips of the first and second movable latch portions 5a and 5b and the first and second fitting members 9a and 9b. Therefore, the second plate driving unit 3b and the first and second latch driving units 6a ₂ and 6b ₂ are electrically linked by the first and second electrical interlocking lines 7a ₂ and 7b ₂ , The second plate driving unit 3b drives the movable plate 2 (the operation of displacing the movable plate 2 from the center position to the lower position), and the first and second latch driving units 6a ₂ and 6b ₂ are the first and second. The operation of driving the movable latch portions 5a and 5b in the direction away from the movable plate 2 is interlocked.

Similarly, when the first plate driving unit 3a displaces the movable plate 2, the first and second latch driving units 6a ₁ and 6b _{1 use} the first and second movable latch units 5a and 5b as the movable plate. Displace in the direction away from 2. That is, the first plate driving unit 3a and the first and second latch driving units 6a ₁ and 6b ₁ are electrically linked by the first and second electrical interlocking lines 7a ₁ and 7b ₁ , One plate driving unit 3a drives the movable plate 2 (an operation to move the movable plate 2 from the central position to the upper position), and the first and second latch driving units 6a ₁ and 6b ₁ are the first and second ones. The operation of driving the movable latch portions 5a and 5b in the direction away from the movable plate 2 is interlocked.

  The first and second movable latch portions 5a and 5b are fitted with the first and second fitting members 9a and 9b by the driving force of the first and second plate driving portions 3a and 3b, respectively. The friction force acts on the mating surface, but the fitting angle and the first and second latches between the tips of the first and second movable latch portions 5a and 5b and the first and second fitting members 9a and 9b, respectively. By appropriately setting the driving force of the driving units 6a and 6b, the latch releasing operation can be smoothly performed.

(Second embodiment)
A second embodiment of an optical device (for example, an optical switch) using the actuator shown in FIG. 3 will be described with reference to FIG.

  The optical switch according to the second embodiment includes an actuator shown in FIG. 3, a rigid arm 88 extended from the movable plate 2, mirrors 90a, 90b, 90c connected to the tip of the rigid arm 88, and a mirror 90a. To 90c, optical waveguides (for example, optical fibers) 101a, 101b, 101c, and 101d that face each other in the vicinity. In a state where the movable plate 2 is held at the center position, the light output from the optical waveguide 101a is reflected by the mirror 90b and enters the optical waveguide 101c. In a state where the first plate driving unit 3a is driven and the movable plate 2 is displaced to the upper position, the light output from the optical waveguide 101a is reflected by the mirror 90a and enters the optical waveguide 101b. In a state where the second plate driving unit 3b is driven and the movable plate 2 is displaced to the lower position, the light output from the optical waveguide 101a is reflected by the mirror 90c and enters the optical waveguide 101d.

  Since the movable plate is accurately held at the upper position, the center position, and the lower position, the positions of the mirrors 90a to 90c attached to the distal end of the rigid arm 88 connected to the movable plate are also accurately determined. Therefore, according to the second embodiment, a three-branch optical switch that accurately reflects the optical axis guided by the optical waveguide 101a in three directions and accurately enters the corresponding optical waveguides 101b to 101d. Can be provided.

(First reference example)
With reference to FIG. 8, the difficulty of wiring when an actuator having a MEMS structure is formed using a single-layer silicon substrate will be described. The basic configuration of the actuator shown in FIG. 8 differs from the basic configuration of the actuator shown in FIG. 2 only in the configuration of the first and second latch drive units 6a and 6b, and the other components are the same. ing.

  In the actuator of FIG. 8, multistage comb type actuators that can be charged independently on the left and right are used as the first and second latch driving units 6a and 6b. The comb-shaped fixed electrodes 12a to 12d and the movable electrodes 11a to 11d connected to the movable latch portion 5 are alternately arranged, and the electrode surfaces of the comb-shaped electrodes are parallel to the movable direction. The first electrical interlocking line 7a connects the first plate driving unit 3a and the fixed electrode 12a. The second electrical interlocking line 7b connects the second plate driving unit 3b and the fixed electrode 12c. The fixed electrode 12a and the fixed electrode 12d are connected by a third electrical interlocking line 7c. However, the fixed electrode 12b and the second plate driving unit 3b cannot be wired. This is because when an actuator having a MEMS structure is formed using a single-layer silicon substrate, the wirings cannot be crossed. However, if wire bonding or the like that can be wired in three dimensions is added, it can be connected. Therefore, the multi-stage comb-type actuator cannot be charged in the left and right directions independently and interlocked with the first and second plate driving units 3a and 3b. Therefore, as shown in FIG. 3, it is desirable to use a gap closing type actuator as the first and second latch driving units 6a and 6b.

(Second reference example)
Referring to FIG. 9, an actuator formed using a single-layer silicon substrate, the “first displacement state” displaced in the first direction (left direction), and the second direction to counter this A reference example of an actuator having a state holding function in three states of “second displacement state” displaced in the right direction and “center state” not displaced in any direction will be described. The actuator shown in FIG. 9 is disclosed in detail in an unpublished prior application (Japanese Patent Application No. 2003-301549) by the same applicant as the present application.

  As shown in FIG. 9, the actuator according to the second reference example includes a fixing portion 55 that supports the entire actuator, a flexible central support portion 56 having one end connected to the fixing portion 55, and a central support portion. A central electrode unit 51 connected to the other end of 56, a fitting unit 52 connected to the fixing portion 55, a flexible first side support portion 57 having one end connected to the fixing portion 55, A first side electrode unit 53 connected to the other end of the first side support portion 57; a flexible second side support portion 58 having one end connected to the fixing portion 55; and a second side. And a second side electrode unit 54 connected to the other end of the support portion 58.

  The central electrode unit 51 includes a movable plate 62 connected to the other end of the central support portion 56, a first central electrode 63 connected to the movable plate 62 in the first direction, and a second direction connected to the movable plate 62. And a second center electrode 64 connected to the movable plate 62 and a center fitting portion (65a, 65b) connected to the movable plate 62 in the first and second directions. The first side electrode unit 53 includes a first side electrode 68 connected to the other end of the first side support portion 57, a first fitting release portion 69 connected to the first side electrode 68, and Have The second side electrode unit 54 includes a second side electrode 71 connected to the other end of the second side support portion 58, a second fitting release portion 72 connected to the second side electrode 71, Have In FIG. 9, the first direction corresponds to the left direction, and the second direction corresponds to the right direction.

  The central fitting portions (65a, 65b) are a first central fitting portion 65a connected to the movable plate 62 in the first direction, and a second central fitting connected to the movable plate 62 in the second direction. And a joint portion 65b. The fitting unit 52 includes a first side fitting portion 52a that fits with the first center fitting portion 65a, and a second side fitting portion 52b that fits with the second center fitting portion 65b. Have.

  The 1st center fitting part 65a has the 1st center nail | claw 82a and the 1st side nail | claw 83a. The second center fitting portion 65b has a second center claw 82b and a second side claw 83b. The first side fitting portion 52 a includes a first fitting claw 81 a and a first convex portion 66 a that contacts the first fitting releasing portion 69. The second side fitting portion 52 b includes a second fitting claw 81 b and a second convex portion 66 b that contacts the second fitting release portion 72.

  The movable plate 62, the first central electrode 63, the second central electrode 64, and the central fitting portions (65a, 65b) are bent in the first direction and the first direction by the deflection of the central support portion 56. Each can be displaced in the opposing second direction.

  Specifically, by generating a potential difference between the first central electrode 63 and the first side electrode 68, an electrostatic attractive force is generated between the first central electrode 63 and the first side electrode 68, The central electrode unit 51 including the first central electrode 63 is displaced in the first direction, and the first side electrode unit 53 including the first side electrode 68 is displaced in the second direction. On the other hand, by generating a potential difference between the second central electrode 64 and the second side electrode 71, an electrostatic attractive force is generated between the second central electrode 64 and the second side electrode 71. The central electrode unit 51 including the central electrode 64 is displaced in the second direction, and the second side electrode unit 54 including the second side electrode 71 is displaced in the first direction.

  The fitting unit 52 is fitted with the central electrode unit 51 to thereby displace the central electrode unit 51 in the first direction, “first displacement state”, and in the second direction, “second displacement state”. ”And“ central state ”that is not displaced in any of the first and second directions.

  Specifically, the first side fitting portion 52a is fitted to the first fitting claw 81a and the first central claw 82a of the first central fitting portion 65a, thereby moving the movable plate 62 to the center. Keep in state. The first side fitting portion 52a is fitted with the first fitting claw 81a and the first side claw 83a of the first center fitting portion 65a, thereby moving the movable plate 62 to the second displacement. Keep in state. That is, the first central claw 82a prevents the movable plate 62 from moving in the first direction relative to the central state, and the first side claw 83a prevents the movable plate 62 from moving in the second displacement state. It is prevented from moving in the direction of 1. On the other hand, the 2nd side fitting part 52b hold | maintains the movable plate 62 to a center state by fitting with the 2nd fitting nail | claw 81b and the 2nd center nail | claw 82b of the 2nd center fitting part 65b. To do. The second side fitting portion 52b is fitted with the second fitting claw 81b and the second side claw 83b of the second center fitting portion 65b, thereby moving the movable plate 62 to the first displacement. Keep in state. In other words, the second central claw 82b prevents the movable plate 62 from moving in the second direction relative to the central state, and the second side claw 83b prevents the movable plate 62 from moving in the first displacement state. It is prevented from moving in the direction of 2.

  However, as shown in FIGS. 10A and 10B, the MEMS structures manufactured through a series of semiconductor manufacturing processes are in contact with adjacent members 91 and 92 immediately after the manufacturing. (FIG. 10B), and a predetermined gap (for example, 5 μm) determined by the necessary conditions of the semiconductor manufacturing process is necessarily formed between the adjacent members 91 and 92 ( FIG. 10 (a)). The actuator of FIG. 9 manufactured through a series of semiconductor manufacturing processes is no exception. Immediately after the manufacture, as shown in FIG. 10C, the first fitting claw 81a and the first central claw 82a are There is no contact, and the predetermined gap is formed. The same applies to the second fitting claw 81b and the second central claw 82b. For example, when a gap of 5 μm is formed, between the first fitting claw 81a and the first central claw 82a and between the second fitting claw 81b and the second central claw 82b. A gap of 5 μm is formed in each case. Therefore, a gap of 10 μm in total is generated in the first and second directions, and the position of the central electrode unit 51 becomes unstable within the range of 10 μm in the first and second directions in the center state.

(Other embodiments)
As described above, the present invention has been described with reference to the first and second embodiments and examples thereof. However, it should be understood that the description and drawings constituting a part of this disclosure limit the present invention. is not. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art. That is, it should be understood that the present invention includes various embodiments not described herein. Therefore, the present invention is limited only by the invention specifying matters according to the scope of claims reasonable from this disclosure.

  As described above, according to the inventions related to claims 1 and 5, the movable latch portion 5 that holds the state of the movable plate 2 has an irreversible structure, so that a predetermined distance between members necessary for forming the MEMS structure can be obtained. The gap can be filled by simple post-processing and a pressurized contact state can be created. Therefore, reliable positioning by mechanical fitting between members in an uncharged state is possible. In other words, it is possible to form a normal latch that engages with the uncharged movable plate 2.

  According to the second aspect of the present invention, the first and second plate driving units 3a and 3b can be displaced by applying stress in the first and second directions with respect to the movable plate 2, so that three positions are provided. Mold actuators can be constructed.

  According to the third aspect of the invention, the configuration of the latch driving unit can be reduced, and a three-position actuator can be easily configured even in a two-dimensional structure.

  According to the invention of claim 4, the normal latch can be formed by performing the irreversible operation with a simple operation.

  The present invention can be used for an optical switch that performs optical path switching in an optical device used for optical communication.

It is a top view which shows the actuator concerning the 1st Embodiment of this invention. It is a top view which shows the actuator concerning the 2nd Embodiment of this invention. It is a top view which shows the initial state immediately after manufacture of the actuator concerning the 1st Example which has the actuator shown in FIG.1 and FIG.2 as a basic composition. FIG. 4A is a plan view showing the state (initial state) of the first and second movable latch portions immediately after the initial formation, and FIG. 4B is the first and second after the irreversible operation. It is a top view which shows the state (fitting state) of this movable latch part. FIG. 5 is a plan view showing the actuator in a fitted state (uncharged state) after performing the irreversible operation in FIG. 4B from the state of FIG. 3. FIG. 6 is a plan view showing a state in which the movable plate is displaced from the non-charged state shown in FIG. 5 toward the second plate driving unit. It is a top view which shows the optical device (optical switch) concerning the 2nd Example using the actuator shown in FIG. It is a top view which shows the case where the actuator which has a MEMS structure is formed using a single layer of silicon. It is a top view which shows the actuator concerning the 2nd reference example formed using the single layer silicon substrate. 10 (a) to 10 (c) show that the MEMS structure manufactured through a series of semiconductor manufacturing processes is not formed by contacting adjacent members immediately after the manufacturing. FIG. 5 is a diagram for explaining that a predetermined gap determined by a necessary condition of a semiconductor manufacturing process is formed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Plate support part 2 ... Movable plate 3 ... Plate drive part 3a ... 1st plate drive part 3b ... 2nd plate drive part 4 ... Latch support part 5 ... Movable latch part 5a ... 1st movable latch part 5b ... 2nd movable latch part 6 ... Latch drive part 6a1, 6a2 ... 1st latch drive part 6b1, 6b2 ... 2nd latch drive part 7 ... Electrical interlocking line 7a1, 7a2 ... 1st electrical interlocking line 7b1, 7b2 ... second electrical interlocking line 7c ... third electrical interlocking line 8 ... latch mechanism 8a ... first latch mechanism 8b ... second latch mechanism 9 ... fitting member 9a ... first fitting member 9b ... 2nd fitting member 10 ... Fixed part 11a-11d ... Movable electrode 12a-12d ... Fixed electrode 13 ... Latch member 14 ... Columnar member 15 ... Latch claw 16 ... Prevention member 18 ... Frame 51 ... Central electrode unit 52 ... Fitting Unit 52a ... 1st side fitting part 52b ... 2nd side fitting part 53 ... 1st side electrode unit 54 ... 2nd side electrode unit 55 ... Fixing part 56 ... Center support part 57 ... 1st side support Part 58 ... second side support part 62 ... movable plate 63 ... first center electrode 64 ... second center electrode 65a ... first center fitting part 65b ... second center fitting part 66a ... first Convex part 66b ... second convex part 68 ... first side electrode 69 ... first fitting release part 71 ... second side electrode 72 ... second fitting release part 81a ... first fitting claw 81b ... second fitting claw 82a ... first central claw 82b ... second central claw 83a ... first side claw 83b ... second side claw 88 ... rigid arm 90a-90c ... mirror 101a-101d ... optical waveguide

Claims (5)

A flexible plate support having one end connected to a fixed part that supports the entire actuator;
A movable plate connected to the other end of the plate support and displaceable by bending of the plate support;
A plate driving section for applying stress to the movable plate and displacing the movable plate;
A flexible latch support having one end connected to the fixed portion;
A movable latch part connected to the other end of the latch support part and displaceable by bending the latch support part;
A latch driving section that applies stress to the movable latch section to displace it,
When the plate driver does not apply stress to the movable plate and the latch driver does not apply stress to the movable latch, the movable latch contacts the movable plate and moves the movable plate. Hold the position of the plate,
The actuator, wherein when the plate driving unit displaces the movable plate, the latch driving unit displaces the movable latch unit in a direction away from the movable plate. The plate driving unit is
A first plate driving section for applying stress to the movable plate in a first direction and displacing the movable plate;
2. The actuator according to claim 1, further comprising: a second plate driving unit configured to apply stress to the movable plate in a second direction opposite to the first direction to displace the movable plate.   The actuator according to claim 2, wherein the latch driving unit includes a comb electrode using a gap closing method. The movable latch portion is
A latch member in contact with the movable plate;
A columnar member connected to the latch member;
A latch claw disposed on a side surface of the columnar member;
The actuator according to claim 1, further comprising: a flexible return preventing member that irreversibly holds the columnar member in a displaced state by fitting with the latch claw. A flexible plate support having one end connected to a fixed part that supports the entire actuator;
A movable plate connected to the other end of the plate support and displaceable by bending of the plate support;
A plate driver that applies stress to the movable plate to displace it;
A flexible latch support having one end connected to the fixed portion;
A movable latch part connected to the other end of the latch support part and displaceable by bending the latch support part;
A latch driving section for applying stress to the movable latch section and displacing the movable latch section;
A mirror connected to the movable plate;
A pair of optical waveguides that intersect or face each other in the vicinity of the mirror;
When the plate driver does not apply stress to the movable plate and the latch driver does not apply stress to the movable latch, the movable latch contacts the movable plate and moves the movable plate. Hold the position of the plate,
The optical device, wherein when the plate driving unit displaces the movable plate, the latch driving unit displaces the movable latch unit in a direction away from the movable plate.