JP2002287045A - Parallel flat plate type micro electrostatic actuator, micro optical path switch, micro mechanical switch, and their driving method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a parallel flat plate type electrostatic actuator which can drive a movable electrode with small power consumption and can quickly makes the electrode take an attitude in parallel to a substrate in addition to a tilt attitude as a parallel flat plate type micro actuator which controls the attitude of the movable electrode by electrostatic driving. SOLUTION: A fixed electrode 4 is divided into >=3 parts to make it possible to make the area of the fixed electrode 4 different according to whether or not it is driven when the movable electrode 3 is in motion and has its attitude held, when the movable electrode 3 is changed from a tilt state to another tilt state, the movable electrode 3 and substrate 2 are placed in an entire-surface abutting state wherein they are brought into parallel contact with each other during the state change to improve the operation efficiency, thereby reducing the power consumption.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a parallel plate type micro-actuator for controlling the attitude of a movable electrode by electrostatic drive, a micro-optical path switch for switching an optical path of incident light, a micro-mechanical switch for switching electric wiring, and the like. In the driving method.

[0002]

2. Description of the Related Art A fixed electrode and a movable electrode which is held by a spring structure and is opposed to the fixed electrode are provided. A parallel plate type in which the movable electrode is operated by an electrostatic force generated by applying a voltage between the two electrodes. Is one of the most frequently used actuators among microactuators.

[0003] The parallel plate type micro-electrostatic actuator has a feature that the nature of its movement can be variously changed depending on the relative position of the fixed electrode and the movable electrode and the method of supporting the movable electrode. When the fixed electrode and the movable electrode are placed at positions facing each other as shown in FIG. 4 and the movable electrode is supported in a double-supported beam shape by a spring structure, the movable electrode performs a vertical parallel motion, and is fixed as shown in FIG. When the electrode and the movable electrode are placed at shifted positions, and the movable electrode is supported by a torsion bar that is parallel to the fixed electrode surface and perpendicular to the direction in which the electrode is shifted, the movable electrode performs a rotational motion.

The parallel plate type micro-electrostatic actuator has a very simple structure, so that it is relatively easy to manufacture. In addition, since the mass of the operating structure is small, a high-speed response is possible. An actuator suitable for use in microdevices, such as minimizing the patterning of the electrode section to reduce the power required for driving. The operable type has been applied in fields such as microswitch devices operating at high frequencies and optical switching devices.

[0005]

As described above, the parallel plate type micro-electrostatic actuator is relatively easy to manufacture, can respond at high speed, and requires less driving power than other types of actuators. It has many benefits. However, the parallel plate type micro-electrostatic actuator of the type that performs a rotation operation to control the posture has the following structural problems.

One is that it is necessary to apply a high drive voltage between the electrodes when controlling the attitude of the actuator. Due to the principle of the electrostatic actuator, electrostatic force acts in inverse proportion to the square of the distance between the fixed electrode and the movable electrode. Only when it approaches the fixed electrode and the electrostatic force cannot be supported by the spring force, a large operation can be obtained. For this reason, it is possible to maintain the state in which the movable electrode and the lower substrate are in contact with each other with a low inclination, but it is possible to shift the movable electrode from the initial state of the actuator to the inclined posture, or to shift the movable electrode from one inclined state to another. In order to shift to the inclined state, it is necessary to apply a high potential difference, and there is a problem that large power consumption is required. In order to suppress the overall power consumption, a method of applying a high potential difference in a pulsed manner only at the moment of switching the posture of the actuator, and using a low potential difference to maintain the tilt posture has been used, but still wasteful power consumption Is accompanied.

Another problem is that the posture when the movable electrode is parallel to the substrate in the initial state of the actuator is as follows.
It is difficult to use as a control object. Due to the above-mentioned limitation of the principle of the electrostatic actuator, the balance of the electrostatic force and the spring force is not normally used for the posture control of the actuator, and the posture control at the time of driving the actuator is performed by bringing the movable electrode into contact with the lower substrate and forcing. A method of stopping the operation of the actuator to maintain the posture at that position is used. In this case, the posture control of the actuator is performed at a very high speed. However, when the movable electrode is supported only by the spring force, it takes time to attenuate the spring, so it takes time to brake the posture. There was a problem such as tilting the crab.

[0008] In the same manner as described above, the micro optical path switch and the micro mechanical switch prepared by using the micro electrostatic actuator shorten the device life due to wasteful power consumption, or set the initial state of the actuator to the attitude of the control target. Due to the deviation, the state parallel to the substrate cannot be controlled, and there is a problem that the number of switching is limited.

In view of the above, the present invention is a parallel plate type electrostatic actuator which performs a rotation operation and an attitude control by electrostatic drive, and can be driven with lower power consumption than other electrostatic actuators of the same type. It is another object of the present invention to provide a parallel plate type electrostatic actuator which can take a posture parallel to the substrate in addition to the inclined posture at a high speed. It is also an object of the present invention to provide a micro optical path switch and a micro mechanical switch that use the parallel plate type electrostatic actuator of the present invention and have a lower power consumption and a larger number of switches than conventional ones.

[0010]

In order to solve this problem, first, in the present invention, not only the movable electrode is rotated but also the movable electrode is moved so that the entire surface of the movable electrode can be moved in parallel by receiving a force from below. The electrode is held by a spring structure that can be sufficiently elastically deformed in both the torsion direction and the expansion and contraction direction,
Further, the present invention is characterized in that the fixed electrode is divided into three or more pieces, and each of the divided fixed electrodes has a structure that can be controlled independently.

According to the present invention, when the movable electrode is far from the fixed electrode and the electrostatic force is difficult to act, the fixed electrode can be efficiently transmitted to the movable electrode by using a large area of the fixed electrode. When the electrostatic force is sufficiently large, the fixed electrode can be reduced to a necessary minimum area to reduce the power consumption.

Further, in the present invention, when the movable electrode shifts from one inclined posture to another inclined posture, all the fixed electrodes below the movable electrode are always operated, and the movable electrode is brought into contact with the entire surface in contact with the substrate. This method is characterized in that a method is used in which only the fixed electrode in the vicinity of the portion to be contacted is left, and the potential of the other fixed electrode is adjusted to the movable electrode to shift to the next inclined posture. By using this driving method, when shifting from the inclined posture state to the entire contact state, the operation can proceed while maintaining a state in which the distance between the electrodes, which is a condition where the electrostatic force acts greatly, is kept short. Power consumption can be suppressed. Further, after the transition to the desired tilting posture, only the fixed electrode having the minimum necessary area needs to be driven, so that the power consumption can also be reduced. In addition, the above-mentioned overall contact state in which the movable electrode is parallel to the substrate is one of the attitudes of the movable electrode itself which is very stable, and is an attitude state that substitutes the attitude of the initial state of the actuator. It is also possible to apply as one.

The present invention is characterized in that a projection electrically connected to the movable electrode is provided on the lower surface of the movable electrode, and a third electrode having the same potential as the movable electrode is provided at a position facing the lower substrate. Is characterized by high rigidity. Thus, in the present invention in which the movable electrode is positively contacted with the substrate, the contact point between the movable electrode and the substrate is limited to the protrusion and the third electrode, and the electrostatic force acts on the contact portion. The contact between the movable electrode and the bed can be smoothly performed.

Next, in the present invention, when the movable electrode shifts from the inclined posture state to the above-mentioned entire contact state, a potential difference is sequentially applied to the movable electrode in order from the fixed electrode contributing to the inclination to the fixed electrode. It is characterized by using a driving method. When the same voltage is applied to all fixed electrodes when the movable electrode is inclined, the fixed electrode closer to the contact point between the movable electrode and the lower substrate has a higher contribution to the rotational motion and is inversely proportional to the distance from the contact point. I do. Therefore, when the above-described driving method is used, power consumption can be suppressed as a result of not using a fixed electrode having a low contribution rate to rotation.

As another method different from the above, in the present case, when the movable electrode shifts from the inclined posture state to the above-mentioned full-contact state, the movable electrode is applied to the movable electrode in the order of the fixed electrode far from the fixed electrode contributing to the inclination. The use of a driving method for applying a large potential difference is also described. In this case, a portion having a low contribution to rotation is reinforced, and the operation can be completed in a short time. Therefore, it is possible to aim for low power consumption by shortening the control time.

Further, the present invention is characterized in that the above-described electrostatic actuator is formed on a semiconductor substrate, and a drive circuit for the actuator is separately formed on the substrate. In this case, the size of the device can be reduced and, at the same time, the electrical wiring can be shortened, so that the power consumption can be further reduced.

As described above, the micro-electrostatic actuator of the present invention can be driven more efficiently than other electrostatic actuators of the same type, so that power consumption can be reduced. Also, besides the inclined posture,
It is also possible to take a posture parallel to the substrate at a high speed.
Further, by using the parallel plate type electrostatic actuator of the present invention, it is also possible to provide a micro optical path switch and a micro mechanical switch with low power consumption and a larger number of switching operations than in the past.

[0018]

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

FIG. 1 shows a configuration of a parallel plate type microactuator 1 of the present invention which rotates and controls the attitude by electrostatic drive. FIG. 1 (a) is a side view and FIG. 2 (b).
Shows a top view thereof. The movable electrode 3 is disposed on the substrate 2 at a distance from the substrate 2, and the movable electrode 3 is supported by the support limb 6 and is connected to the substrate 2 via an anchor 7 to which the support limb 6 is connected. The movable electrode 3 is formed of a relatively thick film so as to have high rigidity so as not to be deformed. The center of gravity of the movable electrode 3 is adjusted so that the movable electrode 3 is separated from the substrate 2 when the actuator 1 is not driven. Both ends of the passing line A are supported by two sets of supporting limbs 6. The support limb 6 is made of two elongated beams, and has a structure capable of sufficiently elastically deforming in both the twisting direction and the stretching direction. Therefore, the movable electrode 3 can operate in the rotation direction around the line A and in the direction perpendicular to the surface of the substrate 2 depending on the location and direction of the force.

At a position facing the movable electrode 3 on the surface of the substrate 2, a fixed electrode group 4 composed of four fixed electrodes 4a to 4d faces the movable electrode 3 in a direction orthogonal to the line A. The fixed electrodes 4a, 4b, 4c and 4d can be controlled independently of each other. A third electrode 5 is arranged on the surface of the substrate 2 separately from the fixed electrode group 4, and is electrically connected to the movable electrode 3 at a position on the lower surface of the movable electrode 3 that faces the third electrode 5. The projection 8 is provided with a conductive material, and the third electrode 5 and the movable electrode 3 are electrically connected to each other through the anchor 7 and the supporting limb 6, so that they are always kept at the same potential.

FIGS. 2A to 2D schematically show the operation of the parallel plate type electrostatic actuator 1 of this embodiment. FIG. 2A is a diagram showing an initial state of the electrostatic actuator 1 of the present embodiment. The movable electrode 3 and the fixed electrode group 4 are in an equipotential state, and no electrostatic force acts between the electrodes. Absent. Therefore, the movable electrode is held in the air at a distance from the substrate 2 only by the spring force of the support limb 6.

FIG. 2B is a diagram showing the entire surface of the electrostatic actuator 1 according to the present embodiment in a state of contact with the movable electrode 3 when a potential difference is applied to all of the fixed electrodes 4a to 4d. Then, since the electrostatic force is applied to the entire movable electrode 3 from below, the movable electrode moves downward in parallel, stops in a state of contact with the third electrode 5 via the protrusion 8, and is stabilized.
At this time, the movable electrode 3 and the substrate 2 are in contact with each other, but the movable electrode 3, the projection 8 and the third electrode 5 are conductive and have the same potential. No current flows between them, and the movable electrode 3 has high rigidity and is hardly deformed. Therefore, the movable electrode 3 does not contact the fixed electrode group 4 due to the deformation of the movable electrode 3.
The potential difference between the fixed electrode group 4 and the movable electrode 3 is firmly held. In this state, the upper surface of the movable electrode 3 is parallel to the surface of the substrate 2. In the initial state of the actuator shown in FIG. 2A, the upper surface of the movable electrode 3 is also parallel to the surface of the substrate 2, but the movable electrode 3 is held only by a spring, is weak against disturbance, and has another posture. When it shifts from, it takes time until the vibration of the movable electrode 3 is attenuated. On the other hand, in the case of the entire contact state shown in FIG. 2B, the movement is forcibly suppressed by contacting the substrate 2 via the projection 8, so that the time required for braking is short, and the braking time is very short. stable. Therefore, this whole-surface contact state is sufficiently practical as a control target as one posture state of the movable electrode.

FIG. 2C is a view showing one of the inclined postures of the electrostatic actuator 1 according to the present embodiment, in which a potential difference is given only to the fixed electrode 4 d with respect to the movable electrode 3.
The fixed electrodes 4a to 4c are in an equipotential state with the movable electrode 3. At this time, the right end of the movable electrode 3 in the drawing is pulled downward from the fixed electrode 4d, and the right end of the movable electrode 3 is
And the center of gravity of the movable electrode 3 is pulled upward by the support limb 6, and as a result, the movable electrode 3 assumes a posture inclined to the right in the drawing. In this inclined posture, the movable electrode 3 and the substrate 2 are in contact with each other as in the second posture, but the potential difference between the movable electrode 3 and the fixed electrode 4d is firm due to the same reason as in the case of the entire surface contact state. Is held.

FIG. 2D is a diagram showing one of the inclined postures of the electrostatic actuator 1 of the present embodiment, in a state where only the fixed electrode 4 a is given a potential difference with respect to the movable electrode 3.
The fixed electrodes 4b to 4d are in an equipotential state with the movable electrode 3. At this time, the left end of the movable electrode 3 in the drawing is pulled downward from the fixed electrode 4a, and the left end of the movable electrode 3 is
Then, the center of gravity of the movable electrode 3 is pulled upward by the support limb 6, and as a result, the movable electrode 3 assumes a posture inclined to the left side in the drawing. In this inclined posture, the movable electrode 3 and the substrate 2 are in contact with each other as in the second posture, but the potential difference between the movable electrode 3 and the fixed electrode 4a is firm due to the same reason as in the case of the entire surface contact state. Is held.

Next, a driving method according to the present invention will be described with reference to FIG. In the present invention, FIG.
2B, the voltage is applied between the movable electrode 3 and the entire fixed electrode group 4 to operate the movable electrode. Since the electrostatic force acting between the parallel plates is proportional to the area of the electrode having the opposite potential difference, pulling over the entire area facing the movable electrode 3 naturally increases the driving efficiency and can lead to a reduction in the driving power. it can.

In the present invention, when shifting from the inclined state of FIG. 2 (c) to the inclined state of FIG. 2 (d), the entire surface shown in FIG. A driving method via a contact state is used. Since the electrostatic force has the property of being inversely proportional to the square of the distance between the charge and the opposite charge, the distance between the movable electrode 3 and the fixed electrode group 4 approaching once at the time of the transition between the postures is reduced. If it is possible to shift to the next posture without expanding, it can be said that the driving efficiency is higher than the others. From the inclined posture shown in FIG.
The transition to the full contact state shown in (b) corresponds to this high-efficiency driving method, and is useful for reducing power consumption because waste can be eliminated. FIG. 2D shows the state of the entire contact shown in FIG.
The transition to the inclined state can be easily made simply by leaving the fixed electrode 4a and returning the potentials of the other fixed electrodes to the same potential as the movable electrode 3. At this time, since the fixed electrode 4a and the movable electrode 3 are sufficiently close to each other and a sufficient electrostatic force acts, the fixed electrode contributing to the tilting posture is fixed electrode 4a.
By itself, the movable electrode can sufficiently maintain the inclined posture, and reducing the area of the electrode to which this voltage is applied leads to a reduction in power consumption.

In the above description, the transition from the inclined posture state shown in FIG. 2 (c) to the inclined posture state shown in FIG. 2 (d) is described, but from the inclined posture state shown in FIG. 2 (d) to FIG. )
The same applies to the case of shifting to the inclined posture state indicated by.

From the inclined posture state shown in FIG.
In the transition to the full contact state shown in (b), the fixed electrodes 4c, 4c,
A potential difference may be sequentially applied to the movable electrode 3 in the order of b and 4a. Considering the rotational movement with the contact point between the movable electrode 3 and the substrate 2 as a fulcrum, the moment of the force contributed by an arbitrary minute area of the movable electrode 3 is in a direction orthogonal to the rotation axis from the fulcrum to the minute area part. Is obtained by multiplying the distance and the electrostatic force applied to the same small area portion.Since the distance and the distance between the movable electrode and the fixed electrode in the same small area portion are proportional, the electrostatic force applied to the same portion is It will be inversely proportional to the square of the distance, and the moment of the force is
It will be inversely proportional to the distance. This means that even if a potential difference is applied to the fixed electrodes 4a to 4c at the same time, the contribution to the rotational motion is high in the order of 4c, 4b, and 4a. Therefore, initially, voltage is not applied to the fixed electrode, which has a small contribution to the motion, and the rotation is advanced by the fixed electrode, which has a high contribution, and then voltage is applied to the next fixed electrode with the movable electrode approaching. The driving method described above can be used to increase the driving efficiency of the actuator, and is effective in reducing power consumption. Alternatively, the value of the voltage applied to the fixed electrode is defined as 4c <4c <
4b <4a, and the moment of the force at a position separated from the fulcrum may be increased. In this case, the rotation operation is completed in a shorter time, and a reduction in the voltage by shortening the control time can be expected.

In the above description, the transition from the inclined posture state shown in FIG. 2C to the full contact state shown in FIG. 2B has been described. 2
The same applies to the case of transition to the full contact state shown in (b).

As an example, the case where there are four fixed electrodes has been described above, but at least two electrodes for maintaining the inclined posture and at least one electrode for filling the area between these two electrodes. The number of fixed electrodes may be any number as long as the total number of the fixed electrodes is at least three. When the number of fixed electrodes is large, finer control is possible by the above-described sequential driving. Also,
As an example so far, the rotation axis of the electrostatic actuator is 1
Although two cases have been described, the number of rotation axes may be plural.

Since the parallel plate type actuator is an actuator which can be relatively easily formed by using a semiconductor process, the parallel plate type actuator of the present invention is formed on a semiconductor substrate such as a silicon substrate, and separately formed on the same substrate. A drive circuit for the actuator may be created so that one substrate is provided with both the actuator and the drive circuit. In that case, you can expect a smaller device,
Since the wiring connecting the actuator and the drive circuit is short, further reduction in power consumption can be expected.

The parallel plate type electrostatic actuator 1 of the present invention
By forming a film having a high reflection surface such as aluminum on the upper surface of the movable electrode 3 as a reflection surface, a micro optical path switch can be manufactured. In this case, if light such as laser light is incident on the reflection surface formed on the upper surface of the movable electrode 3, the movable electrode 3 is brought into contact with the entire surface and at least two types of the inclined posture states, for a total of three types. Since the reflecting surface can be accurately oriented in the above directions, a high-performance optical path switch can be realized. In addition, this optical path switch has the same advantages as the above-described parallel plate type electrostatic actuator, such as low power consumption and the possibility of incorporating a drive circuit in the same device.

FIGS. 3A and 3B are conceptual views of the micromechanical switch 11 of the present invention. FIG. 3A is a sectional view, and FIG. 3B is a top view. An insulating film 12 such as a silicon oxide film is laminated on the upper surface of a parallel plate type actuator 1 having the same configuration as that shown in FIG. 1, and two electric wirings 13 and 14 are arranged thereon. For this reason, the movable electrode 3, the electric wiring 13, and the electric wiring 14 are electrically independent. Also, electrical wirings 15 and 16 to be switched are arranged on the substrate 2 as shown in the figure. In this micro mechanical switch 11, when the movable electrode 3 is in the initial actuator state, the wiring 15, 1
When the movable electrode 3 is in the OFF state and the movable electrode 3 is in the state of contact with the entire surface, the wirings 15 and 16 are also in the ON state, and the movable electrode 3 is in the ON state.
When the camera is in an inclined posture in which it is tilted counterclockwise in the drawing, wiring 1
When the movable electrode 3 is in an inclined posture in which the wiring 5 is turned on and the wiring 16 is turned off and the movable electrode 3 is tilted clockwise in the drawing, the wiring 16 can be turned on and the wiring 15 can be turned off. Thus, the micromechanical switch using the parallel plate type electrostatic actuator of the present invention,
By actively utilizing the entire contact state in addition to the actuator initial state and the inclined posture state, it is possible to provide a micromechanical switch capable of performing various types of switching with a simple configuration compared to the related art. At the same time, this mechanical switch has the same advantages as the above-described parallel plate type electrostatic actuator, such as low power consumption and the possibility of incorporating a drive circuit in the same device.

[0034]

As described above, in the present invention, the movable electrode of the parallel plate type actuator can be moved in both the torsion direction and the expansion / contraction direction so that the movable electrode can perform not only a rotational movement but also a parallel movement. The fixed electrode is divided into three or more, and the divided fixed electrodes can be independently controlled. With these structures, the fixed electrode has a large area and the movable electrode can be operated efficiently when performing the operation of attracting the entire movable electrode, and the fixed electrode has a small area when the inclined position of the movable electrode is maintained. The posture can be maintained well, and the power consumption of the actuator can be suppressed.

Further, in the present invention, when the actuator is shifted from the inclined position to another inclined position, all the fixed electrodes below the movable electrode are always activated, and the transition is made once to the entire contact state where the entire movable electrode is in contact with the substrate. Then, only the fixed electrode in the vicinity of the portion to be contacted is left, and the driving method is used in which the potential of the other fixed electrode is adjusted to the movable electrode to shift to the next inclined posture, thereby reducing the power consumption of the actuator. A driving method can be provided.

In the present invention, when shifting from the inclined posture state to the full contact state, the voltage is sequentially applied to the divided fixed electrodes in ascending order from the part where the movable electrode is inclined and approaching. And a driving method in which a higher voltage is applied in the order of increasing the distance from the portion where the movable electrode is close to the inclined position, and both can obtain the result of increasing the driving efficiency of the actuator.

Further, according to the present invention, the size of the device can be reduced by forming the electrostatic actuator on a substrate such as silicon by using a semiconductor process and incorporating a drive circuit separately formed on the substrate. at the same time,
Since the electric wiring can be shortened, further lower power consumption can be realized.

By using the micro-electrostatic actuator of the present invention, it is possible to provide a micro-optical path switch and a micro-mechanical switch that consume less power and have a larger number of switches than conventional ones due to the various effects described above. it can.

[0039]

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a parallel plate type microactuator of a type that controls a posture by performing a rotational operation by electrostatic drive according to the present invention.

FIG. 2 is a diagram showing an operation mode of the electrostatic actuator shown in FIG.

FIG. 3 is a conceptual diagram of a micro mechanical switch according to the present invention.

FIG. 4 is a conceptual view of a conventional parallel plate type micro electrostatic actuator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Parallel plate-type micro electrostatic actuator 2 Substrate 3 Movable electrode 4a-4d Fixed electrode 5 3rd electrode 6 Supporting limb 7 Anchor 8 Projection 11 Micro mechanical switch 12 Insulating film 13,14 Switching electric wiring 15,16 Switching object Become electrical wiring

Claims (20)

[Claims] 1. A fixed electrode disposed on a substrate and a movable electrode opposed to the fixed electrode at a small distance, and generated by applying a voltage between the fixed electrode and the movable electrode. In a parallel plate type micro electrostatic actuator of a type in which the movable electrode is tilted by an electrostatic force,
The movable electrode is supported by a spring structure capable of elastically deforming sufficiently for both torsion and expansion and contraction. On the surface of the substrate, three or more fixed electrodes are perpendicular to the rotation axis of the movable electrode. A parallel plate type micro-electrostatic device, wherein each of the plurality of fixed electrodes controls an electric potential independently of the other, in such a manner as to cover the entire position facing the movable electrode. Electric actuator. 2. A stopper according to claim 1, wherein a stopper for preventing direct contact with said plurality of fixed electrodes is formed on a lower surface of said movable electrode, and said stopper on said substrate is provided at a position contacting said stopper. A parallel plate type micro-electrostatic actuator, comprising a movable electrode and a third electrode which is always kept at the same potential. 3. The parallel plate type micro-electrostatic actuator according to claim 1, wherein the rigidity of the supporting limb of the movable electrode is reduced and the rigidity of the movable electrode body is increased by thickening the film. 4. The parallel plate type micro-electrostatic actuator according to claim 1, wherein the substrate is a semiconductor substrate, and a drive circuit for the actuator is separately formed on the semiconductor substrate. 5. The movable electrode according to claim 1, wherein the movable electrode is selected from a combination of the three or more fixed electrodes having a potential difference from the movable electrode. Causes an electric potential difference between the initial state of the actuator held only by the spring force of the support limb and the total number of the movable electrode and the plurality of fixed electrodes, and the movable electrode moves in parallel and moves through the stopper. An electric potential difference is generated only between the movable electrode and some of the plurality of fixed electrodes, and a part of the movable electrode is brought into contact with the third electrode. The parallel plate type micro-electrostatic actuator according to claim 1, wherein the parallel plate type micro-actuator is controlled in several kinds of inclined posture states in which the third electrode is in contact with the third electrode via the stopper and is inclined with respect to the substrate. Method of driving a motor. 6. The apparatus according to claim 5, wherein when the electrostatic actuator is shifted from one inclined posture state to another inclined posture state, the electrostatic actuator is passed through the entire contact state once during the transition. And a method of driving the parallel plate type micro electrostatic actuator. 7. The movable electrode according to claim 6, wherein the transition from the inclined posture state to the entire surface contact state is sequentially performed between the movable electrode and the fixed electrode in the order of a fixed electrode which contributes to maintaining the inclined posture. A method for driving the parallel plate type micro-electrostatic actuator, wherein a potential difference is applied. 8. The fixed electrode according to claim 6, wherein a potential difference applied between said movable electrode and said fixed electrode in maintaining said tilted posture in said transition from said tilted posture to said overall contact state is maintained. A method for driving the parallel plate type micro electrostatic actuator, wherein the value is increased in the order of the fixed electrode far from the fixed electrode. 9. A micro optical path switch formed by laminating a reflective film on the upper surface of the movable electrode of the electrostatic actuator according to claim 1. 10. The micro optical path switch according to claim 9, wherein the substrate on which the micro optical path switch is formed is a semiconductor substrate, and a drive circuit for the optical path switch is separately formed on the semiconductor substrate. . 11. The movable optical electrode of the micro optical path switch according to claim 9, wherein the movable electrode is selected from the three or more fixed electrodes by a combination of fixed electrodes having a potential difference with the movable electrode. A potential difference is generated between the initial state of the actuator held only by the spring force and the movable electrode and the total number of the plurality of fixed electrodes, the movable electrode moves in parallel, and the third electrode passes through the stopper. And the entire surface contact state in which the movable electrode and the fixed electrode of the plurality of fixed electrodes generate a potential difference only between the movable electrode and the fixed electrode, and a part of the movable electrode passes through the stopper. The micro optical path switch according to any one of the preceding claims, wherein the micro optical path switch controls several kinds of inclined posture states in which the third electrode is in contact with the third electrode and is inclined with respect to the substrate, and controls the posture of the reflection surface. Dynamic way. 12. The method according to claim 11, wherein the transition from one inclined posture state to another inclined posture state of the electrostatic actuator is performed once through the full contact state during the transition. And a method for driving the micro optical path switch. 13. The fixed electrode according to claim 12, wherein, when shifting from said inclined posture state to said overall contact state, in order of fixed electrodes that are closer to the fixed electrodes contributing to maintaining the inclined posture.
The method of driving the micro optical path switch, wherein a potential difference is sequentially applied to the movable electrode. 14. The fixed state according to claim 12, wherein a potential difference given between said movable electrode and said fixed electrode during the transition from said inclined posture state to said overall contact state contributes to maintaining said inclined posture. The method of driving the micro optical path switch, wherein the value is increased in the order of the fixed electrode far from the electrode. 15. A projection formed on the movable electrode of the electrostatic actuator according to claim 1 and electrically connected to the fixed electrode, the movable electrode, and the third electrode, and a connection between the projections made of a conductor. A micromechanical switch having an electric wiring separately formed on the substrate so as to come into contact with the protrusion when the actuator is driven. 16. The substrate according to claim 15, wherein the substrate on which the micromechanical switches are formed is a semiconductor substrate,
A micromechanical switch, wherein a drive circuit for the micromechanical switch is separately formed on the semiconductor substrate. 17. The micromechanical switch according to claim 15, wherein the movable electrode is connected to the supporting limb by a combination of selection of a fixed electrode having a potential difference from the movable electrode among the three or more fixed electrodes. An actuator initial state held only by the spring force, and a potential difference is generated between the movable electrode and all of the plurality of fixed electrodes,
Between the movable electrode and a part of the plurality of fixed electrodes, and between the movable electrode and a part of the plurality of fixed electrodes, in which the movable electrode moves in parallel and comes into contact with the third electrode via the stopper. Only a potential difference is generated, and a part of the movable electrode is in contact with the third electrode via the stopper to control several kinds of inclined posture states in which the movable electrode takes an inclined posture with respect to the substrate. A method for driving the micromechanical switch, wherein switching of wiring is controlled. 18. The method according to claim 17, wherein, when the electrostatic actuator is shifted from one inclined posture state to another inclined posture state, the electrostatic actuator is caused to pass through the full contact state once during each transition. The driving method of the micro mechanical switch. 19. The method according to claim 18, wherein, when the state is shifted from the inclined posture state to the entire surface contact state, the fixed electrodes are arranged in the order of fixed electrodes that are closer to the fixed electrodes contributing to maintaining the inclined posture.
A method for driving the micro mechanical switch, wherein a potential difference is sequentially applied to the movable electrode. 20. The fixed state according to claim 18, wherein a potential difference given between said movable electrode and said fixed electrode in maintaining said inclined posture is changed in said transition from said inclined posture state to said overall contact state. The method for driving the micromechanical switch, wherein the value is increased in the order of the fixed electrodes far from the electrodes.