JP6914124B2 - Drive device - Google Patents

Description

The present invention relates to the technical field of a drive device such as a MEMS mirror drive device for rotating a driven object such as a mirror.

Mirror drive devices are used in various technical fields such as scanners, barcode readers, printing devices, laser radars, displays, retinal scanning displays, precision measurement, precision processing, and information recording / reproduction. There are MEMS devices manufactured by semiconductor process technology and devices that use inexpensive processing methods such as metal etching, precision metal punching, and laser cutting without using fine processing technology for semiconductor technology. A scanning field that scans light with respect to a predetermined screen area to receive reflected light to read image information, or a display that scans light incident from a light source with respect to a predetermined screen area to display an image. In the field, a mirror drive device having a microstructure (MEMS mirror drive device) is attracting attention.

The following drive devices shown in Patent Document 1 are known as mirror drive devices.
The drive device connects the base portion (movable frame), the rotatable driven portion (mirror), the base portion and the driven portion, and connects the driven portion with an axis along one direction. An elastic portion (torsion bar) having elasticity to rotate as a central axis, and the driven portion resonates with an axis along the one direction as a central axis at a resonance frequency determined by the driven portion and the elastic portion. The base portion is provided with an application portion that applies a slight vibration for rotating the driven portion so as to rotate while rotating.

Patent No. 4958195 Patent Gazette Patent No. 6014234 Patent Gazette

In a mirror drive device having such a configuration, a vibration signal having a resonance frequency determined by a driven portion (mirror) and the elastic portion is applied to a base portion (movable frame), and vibration is propagated from the base portion to the driven portion. An example is shown in which the driven portion is resonantly driven at the resonance frequency. However, such a conventional drive device has a problem that the transmission rate of vibration is not sufficient, the required rotation angle of the mirror cannot be obtained, or a large power consumption is required. Further, there is a problem that the resonance frequency of the mirror cannot be increased.

In such a conventional mirror drive device, there are problems such as expansion of the mirror rotation angle and reduction of power consumption, and problems of increasing the resonance frequency of the mirror to achieve high definition.

In view of the above problems, the drive device of the present invention connects the first base portion, the second base portion supported by the first base portion, the first base portion and the second base portion, and the above-mentioned A first elastic portion having elasticity to rotate the second base portion with an axis along another direction as a rotation axis, a rotatable driven portion (mirror), the second base portion, and the driven portion. A second elastic portion having elasticity to connect and rotate the driven portion with an axis along one direction different from the other direction as a rotation axis, and a second elastic portion arranged on the first elastic portion. The drive source unit is separated from the second base portion by the first elastic portion b (in other words, the drive source portion is separated from and connected to the second base portion), and the drive source portion is the first elastic portion a along the other direction. , The second base portion (including the second elastic portion and the driven portion), the first elastic portion b, the coil portion and the first elastic portion c are continuously deformed and vibrated in a steady wave shape, and the deformed vibration resonates. A periodic exciting force is applied so as to be such that, due to the steady wavy deformation vibration, the driven portion resonates and rotates with an axis along the one direction as a rotation axis. Further, the resonance frequency of the driven portion is a frequency different from the resonance frequency determined by the driven portion and the second elastic portion, which is changed by the steady wave vibration.

In the present invention, since the frequency transition effect and the resonance synthesis effect due to the second base portion, the drive source portion, and the standing wave-like deformation vibration are accurately utilized, a larger rotation angle can be obtained, and higher efficiency and lower power consumption can be obtained. Drive devices can be provided. Further, there is an advantage that the resonance frequency of the driven portion (mirror) can be increased to a higher frequency and higher definition.

Such effects and gains of the present invention will be apparent from the embodiments described below.

It is a top view which conceptually shows the structure of the MEMS mirror drive device which concerns on 1st Example. It is a top view which conceptually shows the mode of operation by the MEMS mirror drive device which concerns on 1st Example. It is a top view which conceptually shows the mode of operation by the MEMS mirror drive device which concerns on 1st Example. It is a side view which conceptually shows the mode of operation by the MEMS mirror drive device which concerns on 1st Example. It is a side view which conceptually shows the mode of operation by the MEMS mirror drive device which concerns on 1st Example. It is a top view which conceptually shows the structure of the MEMS mirror drive device which concerns on 2nd Example. It is a side view which conceptually shows the mode of operation by the MEMS mirror drive device which concerns on 2nd Embodiment. It is a top view which conceptually shows the structure of the MEMS mirror drive device which concerns on 3rd Example. It is a side view which conceptually shows the mode of operation by the MEMS mirror drive device which concerns on 3rd Example. It is a top view which conceptually shows the structure of the MEMS mirror drive device which concerns on 4th Embodiment. It is a side view which conceptually shows the mode of operation by the MEMS mirror drive device which concerns on 4th Embodiment. It is a top view which conceptually shows the structure of the MEMS mirror drive device which concerns on 5th Embodiment. It is a side view which conceptually shows the mode of operation by the MEMS mirror drive device which concerns on 5th Embodiment. It is a top view which conceptually shows the structure of the MEMS mirror drive device which concerns on 6th Embodiment. It is a side view which conceptually shows the mode of operation by the MEMS mirror drive device which concerns on 6th Embodiment. It is a top view which conceptually shows the structure of the MEMS mirror drive device which concerns on 7th Embodiment. It is a top view which conceptually shows the structure of the MEMS mirror drive device which concerns on 8th Embodiment. It is a side view which conceptually shows the mode of operation by the MEMS mirror drive device which concerns on 8th Embodiment.

Hereinafter, embodiments relating to the drive device will be described in order.
The drive device of the present embodiment connects the first base portion, the second base portion supported by the first base portion, the first base portion and the second base portion, and the second base portion. The first elastic portion having elasticity to rotate the shaft along the other direction as the rotation axis, the rotatable driven portion, the second base portion, and the driven portion are connected and the subject is covered. A second elastic portion having elasticity such that the drive portion is rotated around an axis along one direction different from the other directions as a rotation axis, and a coil portion arranged on the first elastic portion (in other words). For example, a coil portion separated and connected to the second base portion by the first elastic portion b) and a magnetic field applying portion that applies a magnetic field to the coil portion, and the coil portion is provided along the other direction. The first elastic portion a, the second base portion (including the second elastic portion and the driven portion), the first elastic portion b, the coil portion, and the first elastic portion c are continuously deformed and vibrated in a steady wave shape. Further, a periodic exciting force is applied so that the deformed vibration resonates, and the driven portion resonates and rotates about an axis along the one direction due to the steady wave-shaped deformed vibration. Further, the resonance frequency of the driven portion is changed by the stationary wave-shaped deformation vibration, and the resonance frequency of the driven portion is a frequency different from the resonance frequency determined by the driven portion and the second elastic portion.

According to the driving device of the present embodiment, the base first base portion and the second base portion supported by the first base portion are connected by a first elastic portion having elasticity. Further, the second base portion and the driven portion (for example, a mirror described later) that is rotatably supported are connected by a second elastic portion having elasticity. The second base portion is formed by the torsional elasticity of the first elastic portion (for example, the elasticity that the second base portion can be rotated about an axis along another direction (for example, the X-axis direction described later) as a rotation axis). It rotates with an axis along the other direction as the axis of rotation. Therefore, the driven portion connected to the second base portion via the second elastic portion also has an axis along the other direction as a rotation axis (the second base portion and the driven portion are integrated). Rotate.

In addition, the driven portion can be rotated by the torsional elasticity of the second elastic portion (for example, the driven portion can be rotated with an axis along one direction (the Y-axis direction described later) as a rotation axis). It rotates with an axis along one direction different from the other directions (preferably orthogonal) as a rotation axis. That is, in the drive device of the present embodiment, the one-axis drive of the driven portion with the axis along one direction as the rotation axis and the axes of both the axis along one direction and the axis along the other direction are used. It is possible to drive the driven portion with a rotation axis of two axes. However, the drive device of the present embodiment may perform multi-axis drive (for example, 3-axis drive, 4-axis drive, etc.) of the driven portion.

In this embodiment, in particular, the coil portion is arranged apart from the second base portion and is arranged on the first elastic portion. When the coil portion is arranged on the first elastic portion, the coil portion is arranged so as to be separated from the second base portion with the first elastic portion b in between. Alternatively, the coil portion is arranged between the first elastic portion b and the first elastic portion c. May be defined as. That is, the coil portion is arranged at a position shifted in a predetermined direction (another direction, the X-axis direction described later) from the location where the second base portion is arranged. More specifically, the coil portion has a first elasticity so that the center of the coil portion (for example, the center of the winding) is arranged at a position shifted in a predetermined direction from the position where the center of the second base portion is arranged. It is placed on the department.

In addition, in the present embodiment, the coil portion is arranged apart from the second base portion. Therefore, as compared with the case where the coil portion is arranged in the second base portion as in Patent Document 2, the distortion of the coil portion does not directly become the distortion of the second base portion. Therefore, the rotational characteristics of the driven portion supported by the second base portion do not deteriorate due to the distortion of the second base portion. In other words, even if the coil portion is distorted, it does not become an unnecessary distortion of the second base portion, a suitable rotation of the driven portion can be maintained, and the operation can be stabilized. In addition, since the distortion of the coil part does not affect the second base part, it is not necessary to increase the rigidity of the coil part, and it is possible to make the shape light and thin, which enables a lighter and more efficient design. ..

In the drive device of the present embodiment, the driven portion rotates due to the force caused by the current flowing through the coil portion. In other words, the driving force for rotating the driven portion is the electromagnetic force caused by the electromagnetic interaction between the coil portion and the magnetic field applying portion.

More specifically, the coil portion is supplied with a control current for rotating the driven portion with an axis along one direction as a rotation axis. The control current is preferably an alternating current having the same frequency as the frequency at which the driven unit rotates with the axis along one direction as the rotation axis. That is, the control current is preferably an alternating current having the same frequency as the frequency of coupled vibration described later, including the driven portion, the second elastic portion, the first elastic portion, the coil portion, and the second base portion. On the other hand, a magnetic field is applied to the coil portion from the magnetic field applying portion. Therefore, a Lorentz force is generated in the coil portion due to the electromagnetic interaction between the control current supplied to the coil portion and the magnetic field applied by the magnetic field applying portion.

The rotational force of the coil portion generated by this Lorentz force is transmitted to the first elastic portion as a force for twisting the coil portion with the axis along the Y-axis direction as the central axis. Then, the torsional force of the coil portion generates a standing wave-like coupled vibration. In other words, the electromagnetic force generated by the coil portion generates coupled vibration between the standing wave-shaped second base portion and the coil portion. Then, this coupled vibration causes the driven portion to resonate and rotate.

At this time, the rotation axis of the coil portion along the Y-axis direction is different from the rotation axis of the driven portion along the Y-axis direction. Specifically, the rotation axis of the coil portion 141 along the Y-axis direction exists at a position shifted by a predetermined distance in the X-axis direction with reference to the rotation axis of the mirror along the Y-axis direction. Therefore, the rotation of the coil portion 141 having the axis along the Y-axis direction as the rotation axis does not directly rotate the driven portion with the axis along the Y-axis direction as the rotation axis.

Here, the above-mentioned coupled vibration (the coupled vibration between the standing wave-shaped second base portion and the coil portion) will be described. In the drive device of the present embodiment, the springs of each part (the first elastic part, the second base part, (including the driven part and the second elastic part), and the coil part) due to the periodic electromagnetic excitation force generated by the coil part. Resonance due to elasticity and mass is generated. In this resonance, the first elastic portion a, the second base portion (including the driven portion and the second elastic portion), the first elastic portion b, the coil portion, and the first elastic portion c are connected along the other directions. It shows a deformed appearance like a triple mode of strings.

At this time, the antinodes and nodes appear along the other directions in the coupled vibration. That is, the first elastic portion a becomes an antinode, the second base portion (including the driven portion and the second elastic portion) becomes a node, the first elastic portion b becomes an antinode, the coil portion becomes a node, and the first elastic portion c Resonance of a mode that makes you angry occurs. Such joint deformation vibration of the first elastic part, the second base part (including the driven part and the second elastic part) and the coil part (hereinafter, the deformation vibration or the connection between the second base part and the coil part). (Abbreviated as oscillating vibration) shows a so-called stationary wavy deformation, and the positions of its antinodes and nodes are substantially fixed.

Then, in the driving device of the present embodiment, the rotational resonance of the driven portion and the coupled vibration (deformed vibration) of the second base portion and the coil portion are generated at the same frequency. Therefore, the resonance frequency of the driven portion is a frequency based on the coupled vibration (deformation vibration) of the standing wave-shaped second base portion and the coil portion. In other words, the resonance frequency of the driven portion coincides with the resonance frequency of the standing wave-shaped deformation vibration.
Further, the resonant frequency of the driven portion is changed by the coupled vibration between the second base portion and the coil portion. Therefore, the resonance frequency of the driven portion at this time is different from the resonance frequency determined by the driven portion and the second elastic portion.

In addition, since the resonance frequency of the driven portion is changed by the coupled vibration of the second base portion and the coil portion, the resonance frequency of the driven portion is typically the driven portion and the second driven portion. The resonance frequency is higher than the resonance frequency determined by the elastic portion, and the driven device rotates at a larger rotation angle, so that a drive device with higher efficiency and lower power consumption can be provided. Therefore, according to the drive device of the present embodiment, when torsional vibration is applied using the same electric power, the transition of the resonance frequency of the driven portion due to the coupled vibration between the second base portion and the coil portion is performed. It is possible to increase the amount of rotation of the driven portion as compared with the case where it is not performed. That is, it is possible to increase the amplitude (rotational amplitude, which is substantially the swing angle sensitivity) of the driven portion per unit electric power.

Further, in the drive device of the present embodiment, the coupled vibration between the second base portion and the coil portion due to the electromagnetic excitation force generated by the coil portion (and the torsional vibration caused by this), that is, the first elastic portion a. , The second base part (including the driven part and the second elastic part), the first elastic part b, the coil part and the first elastic part c are connected and deformed into a steady wave shape along the other direction to resonate and vibrate. In the case, the center of rotation of the coil portion is at the position corresponding to the node. However, the position of the node here is not a strict meaning and may be interpreted as a position close to the node. At this time, the coil portion performs a rotational movement with the axis including the center of rotation (the axis parallel to the extension direction of the second elastic portion = the Y-axis direction described later) as the rotation axis. Therefore, the driving force due to the electromagnetic force generated by the coil portion is also preferably a rotational force having the axis including the center of rotation (the axis parallel to the extension direction of the second elastic portion = the Y-axis direction described later) as the rotation axis.

Then, the resonance can be suitably increased by matching the vibration form due to the resonance of the coil portion with the form of the exciting force. When a rotational force (and torsional vibration caused by the rotational force) is applied to the coil portion in this way, the resonance is suitably increased, and the coupled vibration between the second base portion and the coil portion is increased, and as a result, the object is covered. Resonance with the driving unit (coupling vibration) makes it possible to obtain a larger rotational amplitude of the driven unit with a smaller driving force. However, the coincidence between the vibration form of the coil portion and the form of the exciting force referred to here does not have to be a strict match. Can be obtained. Therefore, in consideration of the balance with other design conditions, it is sufficient to adjust the matching between the vibration form and the excitation force form as appropriate.

Further, in the coupled vibration of the second base portion and the coil portion, the position of the vibration node on the second base portion corresponds to the rotation axis of the driven portion, that is, the rotation axis of the second elastic portion. It is preferable to match the position. In this way, unnecessary vibration (translational movement) of the driven portion is suppressed, and the driven portion can be rotated efficiently. However, the match referred to here does not have to be an exact match, and the position of the node may be adjusted as appropriate in consideration of the balance with other design conditions.

In order to realize the above-mentioned coupled vibration, the rigidity of the first elastic portion a, the second base portion (including the second elastic portion and the driven portion), the first elastic portion b, the coil portion and the first elastic portion c. , Mass, length, width, etc. are adjusted. Specifically, it is preferable to adjust the length, width, shape, cross-sectional shape, rigidity, shape, mass, rigidity, coil portion shape, mass, rigidity, etc. of the first elastic portion. By adjusting these, the positions of the nodes and the antinodes become appropriate, the resonance frequency of the driven portion is changed, the above-mentioned coupled vibration is suitably realized, and suitable rotation of the driven portion is realized.

In the present embodiment, when the coil unit is single, it is necessary to superimpose two or more signals in order to drive two or more axes. That is, two drive signals are required to carry around the axis along one direction and around the axis along the other direction, and the two signals are superimposed. Therefore, it is preferable that the drive signal obtained by superimposing the two signals is supplied to the coil unit.

In another aspect 2 of the driving device of the present embodiment, the electromagnetic excitation force generated by the coil portion causes coupled vibration between the second base portion and the coil portion, that is, the first elastic portion a and the second base portion (driven). (Including the part and the second elastic part), the first elastic part b, the coil part, and the first elastic part c are connected to each other and deform and vibrate in a steady wave shape along another direction, resulting in coupled vibration. , The first elastic part a becomes a belly, the second base part (including the driven part and the second elastic part) becomes a node, the first elastic part b becomes a belly (including a node), and the coil part becomes a belly. Resonance of the mode that becomes. At this time, the coil portion is in the abdominal position. Then, the coil portion performs a translational motion in two directions (Z-axis direction) orthogonal to both the other direction and one direction. Therefore, the driving force caused by the electromagnetic force applied to the coil portion is also preferably a translational force in two directions (Z-axis direction).

By applying a translational force in two directions (Z-axis direction) to the coil portion in this way, the resonance form and the direction of the exciting force match, and the resonance can be suitably increased. By suitably increasing the resonance of the coil portion, the coupled vibration between the second base portion and the coil portion is increased, and as a result, the resonance with the driven portion (including the frequency transition effect, etc.) causes a smaller drive. It is possible to obtain a larger rotational amplitude of the driven portion by force. According to this aspect, the operation of the coil portion is a translational motion, which is different from the rotational motion of the driven portion. In other words, it is possible to obtain the rotational motion of the driven portion by using the translational motion of the coil portion.

In another aspect 3 of the drive device of the present embodiment, the electromagnetic excitation force generated by the coil portion causes coupled vibration between the second base portion and the coil portion, that is, the first elastic portion a and the second base portion ( (Including the driven part and the second elastic part), the first elastic part b, the coil part, and the first elastic part c are connected and deformed and vibrated in a steady wave shape along another direction, resulting in resonance vibration. The first elastic portion a becomes an antinode, the second base portion (including the driven portion and the second elastic portion) becomes a node, and the first elastic portion b becomes an antinode (including a node). The coil part resonates in a mode similar to a node. At this time, the coil portion moves in a form in which the coil portion performs a translational motion along the other direction along the other direction (axial direction of the torsion bar). Therefore, the driving force caused by the electromagnetic force applied to the coil portion is also preferably a translational force along the other direction (axial direction of the torsion bar).

By applying a translational force in the other direction along the other direction to the coil portion in this way, the vibrational state due to the resonance of the coil portion and the form of the exciting force can be matched, and the resonance of the coil portion is suitably increased. Can be done. Then, the coupled vibration between the second base portion and the coil portion is increased, and as a result, the resonance of the driven portion (including the effect due to the frequency transition) obtains a larger rotational amplitude of the driven portion with a smaller driving force. Will be possible.

Further, the magnetic circuit for applying a relative force along the other direction becomes a magnetic circuit in the form of generating a magnetic field along the two directions (in the flat coil portion), and the magnetic gap can be made small. Therefore, a large magnetic field can be obtained with a small magnet, and further miniaturization becomes possible.

In another aspect 4 of the drive device of the present embodiment, the electromagnetic excitation force generated by the coil portion causes coupled vibration between the second base portion and the coil portion, that is, the first elastic portion a and the second base portion (covered). (Including the driving part and the second elastic part), the first elastic part b, the coil part, and the first elastic part c are connected and deformed and vibrated in a steady wave shape along the other direction, resulting in resonance vibration. , The first elastic portion a becomes an antinode, the second base portion (including the driven portion and the second elastic portion) becomes a node, and the first elastic portion b becomes an antinode (including a node), and the coil. The part generates resonance in a mode similar to a node. At this time, the coil portion is a relative motion of the coil itself in which the opposite sides of the coil portion approach or separate from each other along the other direction (axial direction of the torsion bar). Therefore, the driving force caused by the electromagnetic force applied to the coil portion is also preferably a relative force in the direction in which the opposite sides of the coil itself approach or separate from each other along the other direction (axial direction of the torsion bar).

By applying a relative force along the other direction to the coil portion in this way, the vibrational state due to the resonance of the coil portion and the form of the exciting force can be matched, and the resonance of the coil portion can be suitably increased. .. By suitably increasing the resonance of the coil portion, the coupled vibration between the second base portion and the coil portion is increased, and as a result, the resonance with the driven portion (including the effect due to the frequency transition) causes a smaller drive. It is possible to obtain a larger rotational amplitude of the driven portion by force.

Further, the magnetic circuit for applying a relative force along the other direction is a magnetic circuit in the form of generating a magnetic field along the two directions in the (flat coil portion), and the magnetic gap can be made small. Therefore, a large magnetic field can be obtained with a small magnet, and further miniaturization becomes possible.

In another aspect 5 of the drive device of the present embodiment, the number of coil portions is two (the drive source portion is added), and the coil portions are arranged on the target with the driven portion interposed therebetween. By arranging in this way, the coupled vibration between the second base portion and the coil portion, that is, the first elastic portion a, the second coil portion, the first elastic portion b, and the second base portion (driven portion and the second). (Including the elastic part), the first elastic part b, the coil part, and the first elastic part c are connected to each other and deform and vibrate in a steady wave shape along another direction, resulting in resonance vibration. The portion (including the driven portion and the second elastic portion) becomes a node and is substantially fixed. In other words, since the driven portion is sandwiched between the driven portions, the vibration mode of the coupled vibration becomes symmetrical, and the node position of the driven portion can be easily adjusted.

In this example, the added movement of the second coil portion is taken as an example in which the coil portion rotates, but it goes without saying that the vertical movement, the horizontal movement, the relative movement, and other movements shown in the other aspects 2 to 4 are shown. Similarly, the shapes of the two coil portions may not be the same, or may be the same. According to this aspect 5, by arranging the arrangement symmetrically, it becomes easy to substantially match the center position and the node position of the driven portion, and the degree of freedom in design can be increased.

In another aspect 6 of the drive device of the present embodiment, the drive source portion is added and the coil portions are arranged on both sides of the driven portion. The right drive source unit 140 is a drive source unit that is responsible for resonant driving around the axis along the Y-axis direction, and the applied magnetic field is oriented along the X-axis direction. The left drive source unit is a drive source unit that drives around the axis along the X-axis direction, and the applied magnetic field is oriented along the Y-axis direction.

In this embodiment, an example in which the coil portion rotates with the movement of the right coil portion is shown, but it goes without saying that vertical movement, horizontal movement, relative movement, and the like may be combined.
According to this aspect 6, the magnetic flux density of the magnetic field can be increased by simplifying the magnetic field applying means, and more efficient driving becomes possible. Further, by arranging the arrangement symmetrically, the same effect as that of the fifth aspect can be enjoyed.

In another aspect 7 of the drive device of the present embodiment, the electrostatic drive method is adopted, and the attractive force of the electrostatic electrode is used. The basic configuration is the same as that of the present embodiment except that the electrostatic force is used instead of the electromagnetic force. In the electromagnetic drive method, suction and repulsive force are used, but in the electrostatic drive method, the suction force is mainly used. Therefore, although the timing of the applied force is slightly different, the basic operation is the same as that of the electromagnetic drive method.

In this embodiment, an example in which the coil portion rotates with the movement of the right coil portion is shown, but it goes without saying that vertical movement, horizontal movement, relative movement, and the like may be combined.
Further, the drive source unit may be added, and the same effect as that of the fifth aspect can be enjoyed by arranging the drive source units symmetrically.

In another aspect 8 of the drive device of the present embodiment, a piezoelectric body is used as the drive source unit. The basic configuration and operation are the same as those in the second embodiment except that the coil portion for electromagnetic drive is replaced with the piezoelectric body.
Combined vibration between the second base part and the piezoelectric part due to the exciting force generated by the piezoelectric part, that is, the first elastic part a, the second base part (including the driven part and the second elastic part), the first When the elastic portion b, the piezoelectric portion, and the first elastic portion c are connected to each other and deform and vibrate in a steady wave shape along another direction to form a coupled vibration, the first elastic portion a becomes an antinode. A mode resonance occurs in which the second base portion (including the driven portion and the second elastic portion) becomes a node, the first elastic portion b becomes an antinode (including the node), and the piezoelectric portion becomes an antinode. .. Then, the piezoelectric portion performs deformation vibration that repeats a concave-convex warp while accompanied by a translational motion in two directions (Z-axis direction) orthogonal to both the other direction and one direction.
Therefore, it is preferable that the driving force applied to the piezoelectric portion is also a force that repeats the concave-convex warp.

By applying a force that repeats the concave-convex warp to the piezoelectric body portion in this way, the resonance shape and the direction of the exciting force match, and the resonance can be suitably increased. By suitably increasing the resonance of the piezoelectric part, the coupled vibration between the second base part and the piezoelectric part is increased, and as a result, the resonance with the driven part (including the frequency transition effect, etc.) further increases the resonance. It is possible to obtain a larger rotational amplitude of the driven portion with a small driving force. According to this aspect, the operation of the piezoelectric portion is a translational motion, which is different from the rotational motion of the driven portion. In other words, the rotational motion of the driven portion can be obtained by using the translational motion of the piezoelectric portion.

Such effects and other gains of this embodiment will be apparent from the examples described below.
As described above, according to the drive device of the present embodiment, the first base portion, the second base portion supported by the first base portion, and the first base portion and the second base portion are connected to each other. A first elastic portion having elasticity to rotate the second base portion with an axis along another direction as a rotation axis, a rotatable driven portion, the second base portion, and the driven portion. On the second elastic portion and the first elastic portion, which are elastic so as to connect the portions and rotate the driven portion with an axis along one direction different from the other directions as a rotation axis. The coil is provided with a coil portion to be arranged (in other words, a coil portion separated and connected to a second base portion by a first elastic portion b) and a magnetic field applying portion that applies a magnetic field to the coil portion. The portions are the first elastic portion a, the second base portion (including the second elastic portion and the driven portion), the first elastic portion b, the coil portion, and the first elastic portion c along the other directions. Is connected to form a steady wave-like deformation vibration (coupling vibration), and a periodic excitation force is applied so that the deformation vibration resonates. Resonant rotation is performed with an axis along the direction as the central axis, the resonance frequency of the driven portion is transitioned by the coupled vibration, and the resonance frequency of the driven portion is a resonance frequency determined by the driven portion and the second elastic portion. Unlike (typically set to a high resonance frequency), the driven is rotated at a larger rotation angle and is more efficient and consumes less because it makes good use of the combined effect of resonance due to the coupled vibration. A power drive can be provided.

Hereinafter, examples of the drive device will be described with reference to the drawings. In the following, an example in which the drive device is applied to the MEMS mirror drive device will be described. (1) First embodiment First, the first embodiment of the MEMS mirror drive device will be described with reference to FIGS. 1 to 5. do.
(1-1) Basic configuration

The basic configuration of the MEMS mirror drive device 100 of the first embodiment will be described with reference to FIG. FIG. 1 is a plan view conceptually showing the basic configuration of the MEMS mirror driving device 100 of the first embodiment.

As shown in FIG. 1, the MEMS mirror driving device 100 of the first embodiment has a first elastic portion 120 including a first base portion 110-1 and first elastic portions 120a-1, 120b-1 and 120c-1. , The second base portion 110-2, the second elastic portion 120-2 composed of the second elastic portions 120a-2 and 120b-2, the mirror 130, the coil portion 141, and the magnetic poles 142a to 142a as the magnetic field applying portion. It is provided with a drive source unit 140 including.

The first base portion 110-1 has a frame shape having a gap inside. That is, the first base portion 110-1 has two sides extending in the Y-axis direction in FIG. 1 and two sides extending in the X-axis direction in FIG. 1, and extends in the Y-axis direction 2. It has a frame shape with a gap surrounded by one side and two sides extending in the X-axis direction. In the example shown in FIG. 1, the first base portion 110-1 has a rectangular shape, but is not limited to this, and for example, other shapes (for example, a rectangular shape such as a square or a circle). Etc.). Further, the first base portion 110-1 is a structure that is the basis of the MEMS mirror driving device 100 of the first embodiment, and is fixed to a substrate or a support member (not shown) (in other words, MEMS). It is preferably fixed inside the system called the mirror drive device 100).

As described above, FIG. 1 shows an example in which the first base portion 110-1 has a frame shape, but it goes without saying that the first base portion 110-1 may have another shape. For example, the first base portion 110-1 may have a U-shape in which a part of the side thereof is an opening. Alternatively, for example, the first base portion 110-1 may have a box shape having a gap inside. That is, the first base portion 110-1 is orthogonal to the two planes distributed on the plane defined by the X-axis and the Y-axis, and the X-axis and the Z-axis (that is, both the X-axis and the Y-axis) (not shown). It has two planes distributed on the plane defined by the axis) and two planes distributed on the plane defined by the Y-axis and the Z-axis (not shown), and is surrounded by these six planes. It may have a box shape having a gap. Alternatively, the shape of the first base portion 110-1 may be arbitrarily changed according to the mode in which the mirror 130 is arranged.

The first elastic portion 120a-1 is a member having elasticity such as a spring made of, for example, silicon, copper alloy, iron alloy, other metal, resin or the like. The first elastic portion 120a-1 is arranged so as to extend in the direction of the X axis in FIG. In other words, the first elastic portion 120a-1 has a shape having a length extending in the direction of the X axis and a short side extending in the direction of the Y axis. However, depending on the setting situation of the resonance frequency described later, the first elastic portion 120a-1 has a shape having a short hand extending in the X-axis direction and a length extending in the Y-axis direction. It may have any other shape. One end of the first elastic portion 120a-1 is connected to the inner side 115-1 of the first base portion 110-1. The other end of the first elastic portion 120a-1 is on the outer side of the second base portion 110-2 facing the inner side 115-1 of the first base portion 110-1 along the direction of the X axis. Be connected.

The first elastic portion 120b-1 is a member having elasticity such as a spring made of, for example, silicon, copper alloy, iron alloy, other metal, resin or the like. The first elastic portion 120b-1 is arranged so as to extend in the direction of the X axis in FIG. In other words, the first elastic portion 120b-1 has a shape having a length extending in the direction of the X axis and a short side extending in the direction of the Y axis. However, depending on the setting situation of the resonance frequency described later, the first elastic portion 120b-1 has a shape having a short hand extending in the X-axis direction and a length extending in the Y-axis direction. May be good. Further, the first elastic portion 120b-1 may have an arbitrary shape, specifically, a shape connecting the second base portion 110-2 and the coil portion 141, and is triangular, rhombic, trapezoidal, or poly. It may have a polygonal shape, a circular shape, an elliptical shape, a free curve shape, or any other shape. One end of the first elastic portion 120b-1 is connected to the outer side of the second base portion 110-2 along the direction of the X axis. The other end of the first elastic portion 120b-1 is connected to the outer side of the coil portion 141 along the direction of the X axis.

The first elastic portion 120c-1 is a member having elasticity such as a spring made of, for example, silicon, copper alloy, iron alloy, other metal, resin or the like. The first elastic portion 120c-1 is arranged so as to extend in the direction of the X axis in FIG. In other words, the first elastic portion 120c-1 has a shape having a length extending in the direction of the X axis and a short side extending in the direction of the Y axis. However, depending on the setting situation of the resonance frequency described later, the first elastic portion 120c-1 has a shape having a short hand extending in the X-axis direction and a length extending in the Y-axis direction. It may have any other shape. One end of the first elastic portion 120c-1 is connected to the outer side of the coil portion 141 along the direction of the X axis. The other end of the first elastic portion 120c-1 is connected to the inner side 116-1 of the first base portion 110-1 along the direction of the X axis.

The second base portion 110-2 has a frame shape having a gap inside. That is, the second base portion 110-2 includes two sides extending in the Y-axis direction in FIG. 1 and two sides extending in the X-axis direction (that is, an axial direction orthogonal to the Y-axis) in FIG. And has a frame shape having a gap surrounded by two sides extending in the Y-axis direction and two sides extending in the X-axis direction. In the example shown in FIG. 1, the second base portion 110-2 has a rectangular shape, but is not limited to this, for example, other shapes (for example, a rhombus, a hexagon, an octagon, etc.). It may have a circular shape, an elliptical shape, etc.).

The second base portion 110-2 is suspended in the gap inside the first base portion 110-1 by the first elastic portions 120a-1 and 120b-1 (and the coil portion 141 and the first elastic portion 120c-1). Arranged to be or supported. The second base portion 110-2 is rotated about the direction along the X axis by the elasticity of the first elastic portions 120a-1 and 120b-1 (and the coil portion 141 and the first elastic portion 120c-1). It is configured as follows.

The second elastic portion 120a-2 is a member having elasticity such as a spring made of, for example, silicon, copper alloy, iron alloy, other metal, resin or the like. The second elastic portion 120a-2 is arranged so as to extend in the direction of the Y axis in FIG. In other words, the second elastic portion 120a-2 has a shape having a length extending in the Y-axis direction and a short side extending in the X-axis direction. However, depending on the setting situation of the resonance frequency described later, the second elastic portion 120a-2 has a shape having a short hand extending in the Y-axis direction and a length extending in the X-axis direction. May be good. One end of the second elastic portion 120a-2 is connected to the inner side of the second base portion 110-2. The other end of the second elastic portion 120a-2 is connected to one end of the mirror 130 facing the inner side of the second base portion 110-2 along the Y-axis direction.

The second elastic portion 120b-2 is a member having elasticity such as a spring made of, for example, silicon, copper alloy, iron alloy, other metal, resin or the like. The second elastic portion 120b-2 is arranged so as to extend in the direction of the Y axis in FIG. In other words, the second elastic portion 120b-2 has a shape having a length extending in the Y-axis direction and a short hand extending in the X-axis direction. However, depending on the setting situation of the resonance frequency described later, the second elastic portion 120b-2 has a shape having a short hand extending in the Y-axis direction and a length extending in the X-axis direction. May be good. One end of the second elastic portion 120b-2 is connected to the inner side of the second base portion 110-2 along the Y-axis direction. The other end of the second elastic portion 120b-2 is the mirror 130 (on the side to which 120a-2 is not connected) facing the inner side of the second base portion 110-2 along the Y-axis direction. Connected to the end.

The mirror 130 is arranged so as to be suspended or supported by the second elastic portions 120a-2 and 120b-2 in the gap inside the second base portion 110-2. The mirror 130 is configured to rotate about an axis along the Y-axis direction as a rotation axis due to the elasticity of the second elastic portions 120a-2 and 120b-2.

The drive source unit 140 generates torsional vibration required for rotating the mirror 130 about an axis along the Y-axis direction with the first elastic portion 120b-1, the second base portion 110-2, and the second elastic portion. It is added to the mirror 130 through the portion 120а-2 and the second elastic portion 120b-2. That is, as will be described later, the first elastic portion 120а-1, the second base portion 110-2 (including the mirror 130, the second elastic portion 120а-2, and 120b-2), the first elastic portion 120b-1, and the coil. A vibrating force for connecting the portions 141 and the first elastic portions 120c-1 to resonate in a standing wave shape (coupling vibration described later) can be applied. Further, it may be configured so that a force can be applied to the second base portion 110-2. Specifically, by applying a twisting force around the axis along the X axis to the second base portion 110-2, even if a force for rotating the second base portion 110-2 and the mirror 130 connected to the second base portion 110-2 is applied. good.

More specifically, the drive source unit 140 is a drive source unit that applies a force caused by an electromagnetic force, and is a magnetic pole forming a coil unit 141 and a magnetic field applying unit fixed to the first base unit 110-1. It includes 142a, 142b, 142c, 142d, 142e and 142f. In this case, a desired current is applied to the coil unit 141 at a desired timing from a drive source unit control circuit (not shown), and an electromagnetic interaction occurs between the coil unit 141 and the magnetic poles 142a to 142f. Occurs. As a result, electromagnetic force is generated due to electromagnetic interaction. This electromagnetic force is transmitted to the mirror 130, the first elastic portion 120 (120a-1, 120b-1, 120c-1) and the like as torsional vibration or as a driving force.

The coil portion 141 includes, for example, a winding made of a material having a relatively high conductivity (for example, gold, copper, aluminum, etc.). It may be formed by plating, vapor deposition, or the like on a structural material of the same material as the first elastic portion or the base portion (first base portion 110-1, second base portion 110-2). Alternatively, it may be formed on a structural material of another material by plating, vapor deposition, etching, or the like. In the first embodiment, the coil portion 141 has a rectangular plate shape. In particular, the length of two of the four sides of the coil portion 141 along the X-axis direction is shorter than the length of the two sides of the four sides of the coil portion 141 along the Y-axis direction. That is, in the first embodiment, the coil portion 141 has a rectangular shape. However, the coil portion 141 may have an arbitrary shape (for example, a square, a rhombus, a parallelogram, a circle, an ellipse, a polygon, or any other loop shape).

The coil portion 141 is arranged apart from the second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130), and is arranged on the first elastic portion 120. In other words, the coil portion 141 is separated from the second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130) with the first elastic portion 120b-1 in between. Be placed. That is, the coil portion 141 is in a predetermined direction (other direction, X-axis direction) from the position where the second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130) is arranged. It is placed in the shifted position. More specifically, the coil portion 141 is located at a position shifted in a predetermined direction from the position where the center of the second base portion 110-2 (that is, the center of rotation or the center of gravity of the mirror 130) is arranged (for example, the center of the coil portion (for example). It is arranged on the first elastic portion 120 so that the center of the winding or the center of gravity) is arranged. In other words, the coil portion is arranged between the first elastic portion 120b-1 and the first elastic portion 120c-1. In addition, the coil portion 141 includes a first elastic portion 120а-1, a second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and a mirror 130), a first elastic portion 120b-1, and a coil portion. 141, the first elastic portion 120c-1 is arranged inside the first base portion 110-1 so as to be arranged along the X-axis direction.

The coil portion 141 may have a structure having a lower rigidity than the second base portion 110-2. Specifically, the thickness of the coil portion 141 in the direction perpendicular to the paper surface in FIG. 1 is compared with that of the second base portion 110-2. It may be thinned or made of a material having low rigidity. Alternatively, the structure may have low rigidity in shape. It is preferable to consider that the low rigidity mentioned here means that the resonance frequency (natural frequency or eigenvalue) of the component is low. For example, the resonance frequency (natural frequency) of the coil portion 141 is higher than the resonance frequency (natural frequency) of the second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130). It is preferable to consider it low.

The magnetic field applying portion is composed of a permanent magnet, a yoke (magnetic material such as iron) that induces the magnetic field, and the like, and applies a magnetic field to the coil portion 141 from the magnetic poles 142a to 142f. The magnetic poles 142a to 142f are arranged around the coil portion 141. The magnetic poles 142a and 142b are arranged so as to sandwich the coil portion 141 along the Y-axis direction. The explanation will be given using an example in which the magnetic pole 142a is on the exit side (N pole) of the magnetic field and the magnetic pole 142b is on the incident side (S pole) of the magnetic field. Needless to say, the exit side (N pole) and the incident side (S pole) ) May be replaced. Similarly, the magnetic poles 142c and 142e and the magnetic poles 142d and 142f are arranged so as to sandwich the coil portion 141 along the direction of the X axis. The explanation will be given using an example in which the magnetic poles 142c and 142d are on the exit side (N pole) of the magnetic field and the magnetic poles 142e and 142f are on the incident side (S pole) of the magnetic field. Needless to say, the magnetic poles 142c and 142d are incident on the exit side (N pole). It does not matter if the side (S pole) is exchanged. Needless to say, the number of magnetic poles may be appropriately set without being limited to the above numerical values. Further, an electromagnet may be used instead of the permanent magnet.

Subsequently, the configuration including the drive source unit 140 will be described with reference to FIG.
FIG. 4 shows a first elastic portion 120а-1, a second base portion 110-2 (including a mirror 130, a second elastic portion 120а-2, and 120b-2), a first elastic portion 120b-1, a coil portion 141, and a first. 1 It is the figure which looked at the elastic part 120c-1 and the magnetic poles 142c-142f from the side view.

As shown in FIG. 4, the first elastic portion 120а-1, the second base portion 110-2 (including the mirror 130, the second elastic portion 120а-2, 120b-2), the first elastic portion 120b-1, and the coil portion. 141 and the first elastic portion 120c-1 are connected and resonate in a standing wave shape. In the vibration state at this time, a node appears at a position corresponding to the center of the mirror 130, that is, at the connection portion between the second base portion 110-2 and the second elastic portion 110-2, and the node appears at the center position of the coil portion 141. The belly appears at the first elastic portions 120a-1, 120b-1, and 120c-1. Since this resonance will be described in detail as the coupled vibration of the standing wave-shaped second base portion and the coil portion in the section of the mode of operation, only the outline thereof will be described here.
(1-2) Operation of MEMS mirror drive device

Subsequently, with reference to FIGS. 2, 3, 4, and 5, the mode of operation of the MEMS mirror drive device 100 of the first embodiment (specifically, the mode of operation of rotating the mirror 130) will be described. do. Here, FIGS. 2 and 3 are plan views conceptually showing the mode of operation by the MEMS mirror driving device 100 according to the first embodiment. 4 and 5 are side views conceptually showing a mode of operation by the MEMS mirror driving device 100 according to the first embodiment. (The magnetic poles 142a and 142b are omitted.)

First, the rotation of the mirror 130 about the axis along the X-axis direction will be described.
During operation of the MEMS mirror drive device 100 of the first embodiment, a desired current is applied to the coil unit 141 at a desired timing from a drive source unit control circuit (not shown), and the coil unit 141 and the magnetic poles 142a and 142b An electromagnetic interaction occurs between the two. As a result, electromagnetic force is generated due to electromagnetic interaction. This electromagnetic force is transmitted to the second base portion 110-2 as a twisting force or torsional vibration of the coil portion 141 with the axis along the X-axis direction as the central axis via the first elastic portion.

Here, the direction of the electromagnetic force due to the electromagnetic interaction between the coil portion 141 and the magnetic pole 142a is from the back side (back side of the paper surface) to the front side (front side of the paper surface) in FIG. The direction of the electromagnetic force due to the electromagnetic interaction between the coil portion 141 and the magnetic pole 142b is from the front side to the back side in FIG. As a result, this electromagnetic force is applied to the first elastic portions 120a-1, 120b-1 and 120b- with the extension direction (direction along the X axis) of the first elastic portions 120a-1, 120b-1 and 120c-1 as the rotation axis direction. 1 and 120c-1 are rotated, and the coil portion 141 is rotated. As a result, the second base portion 110-2 rotates about an axis along the direction of the X axis, and the mirror 130 supported by the second base portion 110-2 also follows the direction of the X axis. It rotates around the axis.

The second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130) may repeat the rotation operation at a frequency lower or higher than the mirror resonance frequency described later. For example, when the MEMS mirror driving device 100 of the first embodiment is applied to a display (or a head-mounted display), the second base portion 110-2 (second elastic portions 120a-2, 120b-2 and the mirror 130) (Including) may repeat the rotation operation at a frequency (for example, 60 Hz) corresponding to, for example, the scanning cycle or the frame rate of the display.

Alternatively, the second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130) is a suspension portion such as the second base portion 110-2 and the mirror 130 and the first elastic portion 120. The rotation operation at a more determined resonance frequency may be repeated. Specifically, the second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130) includes suspended portions such as the second base portion 110-2 and the coil portion 141, and the second base portion 110-2. 1 The elastic portions 120a-1, 120b-1 and 120c-1 may be rotated so as to resonate at a resonance frequency determined. For example, the moment of inertia about the axis of the suspended portion such as the second base portion 110-2 (including the mirror 130 and the like) and the coil portion 141 along the X axis (more specifically, the second base portion 110-2). Around the axis along the X axis of the suspended portion consisting of the entire system called the second base portion 110-2, which also takes into account the masses of the second elastic portions 120a-2 and 120b-2 and the mirror 130 provided inside. If the moment of inertia) is I1 and the torsional spring constant when the first elastic portions 120a-1, 120b-1 and 120c-1 are regarded as one spring, the second base portion 110 -2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130) has a resonance frequency specified by (1 / (2π)) × √ (k1 / I1), or is near (or near) the resonance frequency. , (1 / (2π)) × √ (k1 / I1) N times (where N is an integer of 1 or more) resonance frequency) with the axis along the direction of the X axis as the central axis It may rotate.

Subsequently, with reference to FIGS. 3, 4, and 5, the rotation of the mirror 130 about the axis along the Y-axis direction will be described. During operation of the MEMS mirror drive device 100 of the first embodiment, a desired control current is applied to the coil unit 141 at a desired timing from a drive source unit control circuit (not shown).

The control current includes a current component for rotating the mirror 130 with an axis along the Y-axis direction as a rotation axis. In the first embodiment, the mirror 130 may be resonantly rotated at a resonance frequency determined by the mirror 130 and the second elastic portions 120a-2 and 120b-2. Further, the resonance frequency determined by the mirror 130 and the second elastic portions 120a-2 and 120b-2 is resonated in the Y-axis direction at the frequency transitioned by the coupled vibration of the second base portion 110-2 and the coil portion 141. The axis along the axis may be rotated as a rotation axis.

The transition of the resonance frequency of the mirror 130 described above will be described in detail in the method of adjusting the resonance frequency in coupled vibration, which will be described later.

Here, as shown in FIG. 3, a control current flowing in the counterclockwise direction is supplied to the coil unit 141, and a magnetic field from the magnetic poles 142c and 142d to the magnetic poles 142e and 142f is applied to the coil unit 141. .. By applying an electric current to the coil portion 141, an electromagnetic interaction occurs between the coil portion 141 and the magnetic pole 142c magnetic pole 142d, magnetic pole 142e and 142f.

The direction of the electromagnetic force due to the electromagnetic interaction between the coil portion 141 and the magnetic poles 142c and 142d is from the back side (back side of the paper surface) to the front side (front side of the paper surface) in FIG. The direction of the electromagnetic force due to the electromagnetic interaction between the coil portion 141 and the magnetic poles 142e and 142f is from the front side to the back side in FIG.

In other words, as shown in FIG. 4, the direction of the electromagnetic force due to the electromagnetic interaction between the coil portion 141a and the magnetic poles 142c and 142d is from the lower side to the upper side in FIG. The direction of the electromagnetic force due to the electromagnetic interaction between the coil portion 141b, the magnetic pole 142e, and the magnetic pole 142f is from the upper side to the lower side in FIG. That is, electromagnetic forces in different directions are generated on the two long sides of the coil portions 141 facing each other along the X-axis direction. In other words, electromagnetic force acting as a couple is generated on the two long sides 141a and 141b of the coil portions 141 facing each other along the X-axis direction. Therefore, the coil portion 141 rotates in the clockwise direction in FIG.

On the other hand, since the control current is an alternating current, the control current flowing in the clockwise direction is supplied to the coil unit 141 after a half cycle. Therefore, the coil portion 141 rotates in the counterclockwise direction in FIG. As a result, the coil unit 141 repeatedly rotates about an axis along the Y-axis direction as a rotation axis.

The repetitive rotation of the coil 141 as described above is transmitted to the first elastic portion 120 and the second base portion 110-2 as torsional vibration of the coil portion 141 centered on the axis along the Y-axis direction, and has a standing wave shape. Generates a coupled vibration of.

At this time, the rotation axis of the coil portion 141 along the Y-axis direction is different from the rotation axis of the mirror 130 along the Y-axis direction. Specifically, the rotation axis of the coil portion 141 along the Y-axis direction exists at a position shifted by a predetermined distance in the X-axis direction with reference to the rotation axis of the mirror 130 along the Y-axis direction. Therefore, the rotation of the coil portion 141 with the axis along the Y-axis direction as the rotation axis does not directly rotate the mirror 130 with the axis along the Y-axis direction as the rotation axis. In other words, the coil portion 141 of the coupled vibration for rotating the mirror 130 instead of applying a force that gives a twist in the rotation direction to the mirror 130 (supported by the second base portion 110-2) itself. Excitation force (torsional vibration) is applied as an energy source.

Subsequently, the coupled vibration of the standing wave-shaped second base portion and the coil portion will be described with reference to FIG. Due to the rotational force generated by the coil portion 141, the first elastic portion 120a-1, the second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130), and the first elastic portion 120b- 1. The coil portion 141 and the first elastic portion 120c-1 are connected to each other and deform and vibrate in a steady wave shape along the other direction, resulting in resonance. In other words, the first elastic portion 120a-1, the second base portion 110-2 (including the second elastic portion 120a-2, 120b-2 and the mirror 130), the first elastic portion 120b-1, the coil portion 141, and The first elastic portions 120c-1 are connected to each other and deform and vibrate along the X-axis direction in a state like a triple mode of the strings. That is, the first elastic portion 120a-1, the second base portion 110-2 (including the second elastic portion 120a-2, 120b-2 and the mirror 130), the first elastic portion 120b-1, the coil portion 141, and the first. 1 The elastic portion 120c-1 exhibits a deformation vibration in which a part thereof becomes an antinode of the coupled vibration and the other part becomes a node of the coupled vibration.

In the above-mentioned standing wave-like coupled vibration, a node appears at the center of the coil portion 141. A node appears at the center of the second base portion 110-2, that is, the center of rotation of the mirror 130, and at the center of the rotation axis of the second elastic portion. A belly appears in the first elastic portions 120a-1, 120b-1, and 120c-1.
That is, the coil portion 141 is located at the node position in the standing wave wave, and the form of the generated (repeated rotation) force of the coil portion 141 matches the form of movement of the coil portion 141 in the coupled vibration.
On the other hand, the center of rotation of the mirror 130 is at the node position. Therefore, as shown in FIG. 4, there is no vertical movement (direction along the Z axis) in the form of movement, and only rotational movement centered on the axis along the direction of the Y axis. The above-mentioned coupled vibration shows a so-called standing wave-like deformed state, and the positions of its antinodes and nodes are substantially fixed.
However, the fact that the mirror 130 or the coil portion 141 is located at the node position does not mean that the mirror 130 or the coil portion 141 is exactly located, but it may be interpreted that the mirror 130 or the coil portion 141 is located near the node. It is better to think that the closer it is to the knot, the more efficiently it rotates.

Such a first elastic portion 120a-1, a second base portion 110-2 (including a second elastic portion 120a-2, 120b-2 and a mirror 130), a first elastic portion 120b-1, a coil portion 141, And the mirror 130 is rotated due to the coupled vibration of the first elastic portion 120c-1. Then, the rotational resonance of the mirror 130 and the coupled vibration of the standing wave-shaped second base portion and the coil portion occur at the same frequency.
Therefore, the resonance frequency of the mirror 130 is a frequency based on the coupled vibration (deformation vibration) of the standing wave-shaped second base portion and the coil portion. In other words, the resonance frequency of the mirror 130 coincides with the resonance frequency of the standing wave-shaped deformation vibration.

In a further aspect, the resonance frequency of the mirror 130 is transitioned by the coupled vibration of the second base portion and the coil portion, so that the mirror 130 has a frequency different from the resonance frequency determined by the mirror 130 and the second elastic portion. Resonance is generated. The resonance frequency of the mirror 130 at this time is typically higher than the resonance frequency determined by the mirror 130 and the second elastic portion. Further, at this time, the rotation angle of the mirror 130 tends to be larger than that in the case where the frequency is not changed due to the coupled vibration.

In order to realize the above-mentioned coupled vibration, the first elastic portion 120a-1, the second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130), and the first elastic portion 120b. -1, the rigidity, mass, length, etc. of the coil portion 141 and the first elastic portion 120c-1 are adjusted. Specifically, the length, cross-sectional shape, rigidity, shape, mass, rigidity of the second base portion 110-2, shape, mass, rigidity, etc. of the coil portion 141 may be adjusted. By adjusting these, the positions of the nodes and the antinodes and the resonance frequency become appropriate, the above-mentioned coupled vibration is preferably realized, and the suitable rotation of the mirror 130 is realized.

Here, the method of adjusting the resonance frequency in the coupled vibration will be described in more detail with reference to FIGS. 4 and 5. In recent years, calculation technology has been developed, and simulations can be easily performed on a personal computer without making a prototype, and the values of the prototype and the simulation have come to match with high accuracy. Here, a method of adjusting the resonance frequency and a method of adjusting the rigidity in coupled vibration will be described as examples by simulation on a personal computer. The resonance frequency of the target mirror 130 is set to about 25 kHz.

(Adjustment 1) First, the resonance frequency of the mirror 130 determined by the mirror 130 and the second elastic portion 120-2 is calculated. It is equipped with a mirror 130, second elastic portions (120a-2, 120b-2), and a second base portion 110-2, and appropriately adjusts the thickness, diameter, length, width, and the like. Then, completely fixed is input as the boundary condition of the second base portion 110-2. If eigenvalue analysis (resonance frequency analysis) is performed with simulation software in this state, the resonance frequency of the mirror 130 determined by the mirror 130 and the second elastic portion 120-2 is calculated. At this time, the dimensions of each part are determined (by iterative calculation) so that the resonance frequency in the rotation direction along the Y-axis direction of the mirror 130 is 25 kHz.

(Adjustment 2) Next, the first elastic parts 120a-1, parts 120b-1 and 120c-1, coil parts 141, and the first base part 110-1 are additionally equipped, and the thickness, length, width, etc. are appropriately adjusted. adjust. In this state, when complete fixing is input as the boundary condition of the first base portion-1, the first elastic portion 120a-1, the second base portion 110-2 (the second elastic portions 120a-2, 120b-2 and the mirror) are input. The coupled resonance frequency and resonance mode of the rotational motion and translational motion of the first elastic portion 120b-1, the coil portion 141, and the first elastic portion 120c-1 (including 130) are calculated (coupling vibration). .. The dimensions (thickness, length, width, size) of each part are adjusted so that the resonance mode at this time becomes a deformed state like the triple mode of the string as shown in FIG. Further, it is preferable to make fine adjustments of each part so that nodes appear at the position corresponding to the rotation axis of the mirror 130 (the center of rotation of the mirror) and the position of the center of rotation of the coil part 141.

If the resonance frequency in the above-mentioned vibration state is calculated to be 25.000 kHz, the frequency of coupled vibration is determined by the resonance frequency of the mirror 130 (mirror 130 (driven portion) and second elastic portion 120) in this state. ) Is adjusted.

(Adjustment 3) Next, it is assumed that the thickness of the first elastic portion 120b-1 is slightly increased, for example. Since the spring rigidity increases in proportion to the cube of the thickness and the mass is proportional to the first power of the thickness (in other words, the rigidity increases but the mass does not increase), the system including the first elastic portion 120b-1. The resonance frequency rises, and the resonance frequency of the coupled vibration rises.

Then, the calculation result by the simulation changes to 25.25 KHz (frequency of coupled vibration = frequency of driven portion) (thickness of the first elastic portion 120b-1 is adjusted). The concept of the vibration state at this time is shown in FIG. The amplitude of the coupled vibration decreases and the angle of rotation of the mirror increases. At this time, it can be seen that the mirror 130 resonates at a frequency different from the frequency determined by the mirror 130 and the second elastic portion 120-2.

On the contrary, when the thickness of the first elastic portion 120b-1 is reduced and the same simulation is performed, the resonance frequency of the coupled vibration is lowered to 24.75 KH, and the amplitude of the coupled vibration is large. Therefore, the touch angle of the mirror 130 becomes smaller. (Adjustment 3, end)

As described above, in this embodiment, the mirror 130 can also resonate at a resonance frequency different from the resonance frequency determined by the mirror 130 and the second elastic portion 120-2. In other words, the resonance frequency of the mirror 130 can be changed by the coupled vibration.

Further, according to calculations of various aspects, typically, the rotation angle of the mirror becomes large when the resonance frequency of the mirror 130 is changed to a high frequency by coupled vibration.

When the rotation direction of the coil portion 141 and the rotation direction of the mirror 130 are in the same direction (referred to as in-phase), the above-mentioned transition frequency (deviation) tends to be large, and the deviation is 1% to 10%. There is an example of degree. Further, as shown in FIG. 4, when the movements of the second base portion 110-2 and the mirror 130 are opposite to each other (referred to as reverse phase), the above-mentioned deviation is small, and the deviation is 0.03% to 2 There is an example of about%.

Alternatively, although it is an example, when the vibration mode of the coupled vibration is set to a lower order mode, that is, a vibration mode close to the double mode of the strings, the above-mentioned transition frequency (deviation) tends to be large. An example of 30% has been confirmed.

Further, contrary to the above-mentioned typical example, there is also a preferable example in which the resonance frequency of the mirror 130 is made low by the coupled vibration. Therefore, the resonance frequency of the mirror 130 is set to the mirror 130 and the second elastic portion 120. It should be added that the frequency may be set lower than the fixed frequency of -2.

Here, regarding the resonance frequency of the mirror 130, the different resonance frequencies (frequency deviations) described above will be mentioned. A structure composed of silicon such as MEMS and a metal spring has a small attenuation as a material, and the resonance peak in the frequency characteristic diagram has a sharp and steep shape. The Q value is a typical numerical value representing the sharpness of this resonance peak. In the MEMS and the metal, the Q value is large, typically about 1500. Here, the deviation of the resonance frequency will be described using the Q value.

The definition of the Q value is that ω is the resonance frequency at the resonance peak, ω1 is the frequency at which the vibration energy is half the resonance peak on the frequency side lower than ω, and ω2 is the half value of the resonance peak on the frequency side higher than ω. The Q value is represented by Q = ω / (ω2-ω1). Substituting the above ω = 25000 Hz and Q = 1500 into this and transforming it, ω2-ω1 = 25000/1500 = 16.67 Hz. Further, due to the symmetry of the resonance peak, the difference between the resonance peak frequency ω and ω1 (ω2) is 16.67 / 2 = 8.34 Hz. That is, in the frequency characteristics of the drive device, when the excitation resonance frequency is 8.34 Hz away from the resonance peak frequency ω, the resonance energy of the system is reduced to half (rotation angle is √ (0.5)). 8.34 Hz is 0.0334% ≈ 0.03% of 25 kHz. Therefore, the resonance energy is halved by the deviation of the resonance frequency (peak frequency) of 0.03%. Therefore, a difference of 0.03% in the resonance frequency can be considered to be a sufficient difference. The above-mentioned example is an example of consideration in the case where the resonance energy is halved, and the above calculation is not limited to this calculation, and the different resonance frequencies may be arbitrarily determined.

As described above, the MEMS mirror drive device 100 of the first embodiment can rotate the mirror 130 with the axis along the X-axis direction as the rotation axis, and at the same time, the mirror with the axis along the Y-axis direction as the rotation axis. The 130 can be resonated and rotated. That is, the MEMS mirror drive device 100 of the first embodiment can perform two-axis drive.

Here, the force for rotating and resonating the mirror 130 with the axis along the Y-axis direction as the rotation axis is not a mode in which the mirror 130 is directly rotated, but an exciting force is applied to the coil portion as an energy source for coupled vibration. This causes the mirror 130 to be resonantly driven.

In addition, in the first embodiment, the first elastic portion 120b-1 is arranged between the second base portion 110-2 holding the mirror 130 and the coil portion 141. As a result, the antinode of the above-mentioned standing wave-shaped coupled vibration appears in the first elastic portion 120b-1. (In other words, the second base portion 110-2 is not a belly). Therefore, as compared with the case where the second base portion 110-2 is deformed and vibrated with a part of the second base portion 110-2 as a belly as shown in Patent Document 2, the deformation vibration of the second base portion is smaller, so that fatigue fracture is less likely to occur. It is possible to extend the life of the MEMS mirror drive device 100.

In addition, by arranging the coil portion 141 away from the second base portion 110-2, a comparative example in which the coil portion 141 is arranged beside the mirror 130 as shown in Patent Document 2, in other words, the first 2 Compared to the MEMS mirror drive device in which the coil portion 141 is arranged on the base portion 110-2, the distortion of the coil portion 141 does not directly distort the second base portion 110-2, and the mirror 130 No strain is applied to the second elastic portion 120-2, which is the support portion of the mirror 130, and the rotation characteristics of the mirror 130 are not deteriorated. In addition, since the distortion of the coil portion 141 does not affect the second base portion 110-2, it is not necessary to increase the rigidity of the coil portion 141 more than necessary, and it is possible to make the shape light and large. Therefore, it is possible to design the coil portion 141 with a lighter weight and higher efficiency.

In particular, the resonance frequency of the driven portion is different from the resonance frequency determined by the driven portion and the second elastic portion. By transitioning the resonance frequency of the driven portion by the coupled vibration of the second base portion and the coil portion and accurately synthesizing the resonance, the driven portion can be rotated at a larger rotation angle, resulting in higher efficiency. It becomes possible to provide a drive device having low power consumption.
(2) Second Example A second embodiment of the MEMS mirror driving device will be described with reference to FIGS. 6 and 7.
(2-1) Basic configuration

The MEMS mirror driving device 101 of the second embodiment will be described with reference to FIG. FIG. 6 is a plan view conceptually showing the basic configuration of the MEMS mirror driving device 101 of the second embodiment. Since the configuration and operation related to the rotation of the mirror 130 about the rotation axis in the direction along the X axis are the same as those in the first embodiment, the configuration and operation are omitted, and the rotation axis in the direction along the Y axis is the center. The configuration and operation related to rotation will be described. Further, with respect to the same configuration as the MEMS mirror driving device 100 of the first embodiment described above, detailed description thereof will be omitted by adding the same reference numerals.

As shown in FIG. 6, in the MEMS mirror driving device 100 of the first embodiment, the first base portion 110-1, the first elastic portions 120a-1, 120b-1 and 120c-1, and the second base portion 110 -2, second elastic portions 120a-2 and 120b-2, a mirror 130, and a drive source portion 140 including a coil portion 141 and a magnetic field applying portion 142. The basic configuration is the same as that of the first embodiment, and the method of applying the magnetic field, the direction of movement of the coil portion 141 due to this, and the form of coupled vibration are different.
The magnetic poles 142c to 142f are arranged around the coil 142, and the magnetic field emitted from the magnetic poles 142c to 142f is in the direction from the outside to the inside of the coil portion.
(2-2) Operation of MEMS mirror drive device

Subsequently, with reference to FIG. 7, the operation related to the rotation about the rotation axis in the direction along the Y axis will be described. FIG. 7 is a side view conceptually showing a mode of operation by the MEMS mirror driving device 101 according to the second embodiment. The position of the coil portion 141 is different from that of the first embodiment, and in the second embodiment, the coil portion 141 is arranged at the antinode position of the coupled vibration. (Note that arranging at the position of the belly here does not mean that the position of the belly is exactly. You can think that the closer the position is to the belly, the more efficient it is.)

A desired current is applied to the coil unit 141 at a desired timing from a drive source unit control circuit (not shown). The coil portion 141 generates a driving force in the vertical direction (direction along the Z axis) in the drawing due to the interaction with the magnetic fields emitted from the magnetic poles 142a to 142f. By this electromagnetic force, the coil unit 141 is reciprocated up and down. This reciprocating motion generates coupled vibration between the second base portion and the coil portion. That is, the first elastic portion 120a-1, the second base portion 110-2 (including the second elastic portion 120a-2, 120b-2 and the mirror 130), the first elastic portion 120b-1, the coil portion 141, and the first. The elastic portions 120c-1 are connected to generate a standing wave resonance. By matching the direction of the electromagnetic force of the coil portion 141 with the direction of movement of the coil portion 141 in the coupled vibration, the amplitude of the coupled vibration is preferably increased. Then, based on the same principle as in the first embodiment, the mirror 130 located at the resonance node is preferably rotated.

Here, the coil portion 141 does not directly rotate the mirror 130. In other words, the coil portion 141 of the coupled vibration for rotating the mirror 130 instead of applying a force that gives a twist in the rotation direction to the mirror 130 (supported by the second base portion 110-2) itself. As an energy source, a vibrating force in the vertical direction (direction along the Z axis) is applied to the coil portion 141. Then, the mirror 130 is rotated by the coupled vibration.
Therefore, the MEMS mirror driving device 101 of the second embodiment can preferably enjoy various effects as in the first embodiment.
(3) Third Example A second embodiment of the MEMS mirror driving device will be described with reference to FIGS. 8 and 9.
(3-1) Basic configuration

The MEMS mirror driving device 102 of the third embodiment will be described with reference to FIG. FIG. 8 is a plan view conceptually showing the basic configuration of the MEMS mirror driving device 102 of the third embodiment. Since the configuration and operation related to the rotation of the mirror 130 about the rotation axis in the direction along the X axis are the same as those in the first embodiment, the configuration and operation are omitted, and the rotation axis in the direction along the Y axis is the center. The configuration and operation related to rotation will be described. Further, with respect to the same configuration as the MEMS mirror driving device 100 of the first embodiment described above, detailed description thereof will be omitted by adding the same reference numerals.

As shown in FIG. 8, in the MEMS mirror driving device 102 of the third embodiment, the first base portion 110-1, the first elastic portions 120a-1, 120b-1 and 120c-1, and the second base portion 110 -2, second elastic portions 120a-2 and 120b-2, a mirror 130, and a drive source portion 140 including a coil portion 141 and a magnetic field applying portion 142. The basic configuration is the same as that of the first embodiment, and the method of applying the magnetic field, the direction of movement of the coil portion 141 caused by the magnetic field, and the form of the coupled vibration related thereto are different.
As shown in FIG. 9, the magnetic poles 142c and 142d are arranged above the coil portion, and the magnetic poles 142e and 142f are arranged below the coil portion. The magnetic field goes from the magnetic pole 142e to the magnetic pole 142c from the bottom to the top, and from the magnetic pole 142d to the magnetic pole 142f from the top to the bottom.
(3-2) Operation of MEMS mirror drive device

Subsequently, with reference to FIG. 9, the rotation operation about the axis along the Y-axis direction will be described. FIG. 9 is a side view conceptually showing a mode of operation by the MEMS mirror driving device 102 according to the third embodiment. The mode of vibration generated in the coil portion 141 is different from that of the first embodiment.

A desired current is applied to the coil unit 141 at a desired timing from a drive source unit control circuit (not shown). Due to the interaction with the magnetic fields emitted from the magnetic poles 142a to 142f, a driving force is generated in the coil portion 141 along the axial direction (direction along the X axis) of the first elastic portion. First elastic portion 120a-1, second base portion 110-2 (including second elastic portion 120a-2, 120b-2 and mirror 130), first elastic portion 120b-1, coil portion 141, and first elastic portion. The coil portion 141 is located near the node of the coupled vibration composed of the portions 120c-1, and the coil portion 141 moves along the axial direction (direction along the X axis) of the first elastic portion. The direction of the force due to the electromagnetic force of the portion 141 and the direction of the movement of the coil portion 141 due to the coupled vibration match, the coupled vibration is formed as in the first embodiment and the second embodiment, and the mirror 130 is formed. Rotate.

Also in this embodiment, the coil portion 141 does not directly rotate the mirror 130, but applies an exciting force as a translational motion in the direction along the X axis to the coil portion 141 as an energy source for coupled vibration.
Therefore, the MEMS mirror driving device 102 of the third embodiment can preferably enjoy various effects as in the first embodiment.
(4) Fourth Example A second embodiment of the MEMS mirror driving device will be described with reference to FIGS. 10 and 11.
(4-1) Basic configuration

The MEMS mirror driving device 103 of the fourth embodiment will be described with reference to FIG. FIG. 10 is a plan view conceptually showing the basic configuration of the MEMS mirror driving device 103 of the fourth embodiment. The configuration and operation related to the rotation of the mirror 130 about the rotation axis in the direction along the X axis are the same as those in the first embodiment, so they are omitted, and the rotation around the rotation axis in the direction along the Y axis is omitted. The configuration and operation of the above will be explained. Further, with respect to the same configuration as the MEMS mirror driving device 100 of the first embodiment described above, detailed description thereof will be omitted by adding the same reference numerals.

As shown in FIG. 10, in the MEMS mirror driving device 100 of the fourth embodiment, the first base portion 110-1, the first elastic portions 120a-1, 120b-1 and 120c-1, and the second base portion 110 -2, second elastic portions 120a-2 and 120b-2, a mirror 130, and a drive source portion 140 including a coil portion 141 and a magnetic field applying portion 142. The basic configuration is the same as that of the first embodiment, and the method of applying the magnetic field, the direction of movement of the coil portion 141 caused by the magnetic field, and the form of the coupled vibration related thereto are different.
As shown in FIG. 11, the magnetic pole 142c is arranged above the coil portion, and the magnetic pole 142e is arranged below the coil portion. The magnetic field is in the direction from the bottom to the top from the magnetic pole 142e to the magnetic pole 142f.
(4-2) Operation of MEMS mirror drive device

Subsequently, with reference to FIG. 11, the rotation operation about the axis of the mirror 130 along the Y-axis direction will be described. FIG. 11 is a side view conceptually showing a mode of operation by the MEMS mirror driving device 103 according to the fourth embodiment. The mode of vibration generated in the coil portion 141 is different from that of the first embodiment.
A desired current is applied to the coil unit 141 at a desired timing from a drive source unit control circuit (not shown). Due to the interaction with the magnetic fields generated from the magnetic poles 142c and 142e, the coil portion 141a generates a driving force in the left-right direction in the figure, and 141b generates a driving force in the right-left direction in the figure, and receives a force that causes the opposite sides of the coil portions to be relatively displaced in opposite directions. .. Therefore, a force that causes the coil itself to expand and contract in the X-axis direction is generated in the coil portion 141.

First elastic portion 120a-1, second base portion 110-2 (including second elastic portion 120a-2, 120b-2 and mirror 130), first elastic portion 120b-1, coil portion 141, and first elastic portion. The coil portion 141 is located near the node of the coupled vibration composed of the portions 120c-1, and the coil portion 141 moves in the X-axis direction. Therefore, the direction of the force due to the electromagnetic force of the coil portion 141 coincides with the direction of the movement of the coil portion 141 due to the coupled vibration, and the resonance is preferably increased.

Also in this embodiment, the coil unit 141 does not directly rotate the mirror 130, but resonates and drives the mirror 130 by applying the relative displacement force as an energy source for coupled vibration.
Therefore, the MEMS mirror driving device 100 of the fourth embodiment can preferably enjoy various effects as in the first embodiment.
(5) Fifth Example A fifth embodiment of the MEMS mirror driving device will be described with reference to FIGS. 12 and 13.
(5-1) Basic configuration and operation

FIG. 12 is a plan view conceptually showing the basic configuration of the MEMS mirror driving device 104 of the fifth embodiment. FIG. 13 is a side view conceptually showing the basic operation of the MEMS mirror driving device 104 of the fifth embodiment.

The fifth embodiment is an example in which the drive source unit 150 is added, the number of coil units is two, and the mirror 130 is arranged on both sides as compared with the first embodiment. 120b2-1 is added to the first elastic portion 120, and the first elastic portion 120 is composed of the first elastic portions 120a-1, 120b2-1, 120b-1 and 120c-1. The coil portion 151 has a shape close to a square with respect to the vertically long rectangle of the coil portion 141. Needless to say, the coil portion 151 may have an arbitrary shape as in the first embodiment.

One end of the first elastic portion 120a-1 is connected to the inner side 115-1 of the first base portion 110-1. The other end of the first elastic portion 120a-1 is connected to the left side of the coil portion 151 along the direction of the X axis. One end of the first elastic portion 120b2-1 is connected to the right side of the coil portion 151 along the direction of the X axis. The other end of the first elastic portion 120b2-1 is connected to the outer side of the second base portion 110-2. One end of the first elastic portion 120b-1 is connected to the outer side of the second base portion 110-2 along the direction of the X axis. The other end of the first elastic portion 120b-1 is connected to the outer side of the coil portion 141 along the direction of the X axis. The other end of the first elastic portion 120c-1 is connected to the inner side 116-1 of the first base portion 110-1 along the direction of the X axis.

The second base portion 110-2 has the first elastic portions 120b2-1 and 120b-1 (and the coil portions 141, 150 and the first elastic portions 120a-1, 120c) in the gap inside the first base portion 110-1. It is arranged to be suspended or supported by -1). The second base portion 110-2 is directed along the X axis due to the elasticity of the first elastic portions 120b2-1 and 120b-1 (and the coil portions 141, 150 and the first elastic portions 120a-1, 120c-1). It is configured to rotate around the central axis.

The basic configuration of the drive source unit 150 including the coil 151 is the same as that of the drive source unit 140. Further, with respect to the same configuration as the MEMS mirror driving device 100 of the first embodiment described above, detailed description thereof will be omitted by adding the same reference numerals.

Regarding the operation related to the rotation of the mirror 130 about the rotation axis in the direction along the X axis, the coil unit 141 driven by the drive source unit 140 and the coil unit 151 driven by the drive source unit 150 may be driven in the same phase. Often, the basic operation is the same as that of the first embodiment, and thus is omitted.

Next, the configuration and operation related to rotation about the rotation axis in the direction along the Y axis will be described. A desired control current is applied from a drive source unit control circuit (not shown), and a rotational force is generated in the coil units 141 and 151 due to the electromagnetic interaction between the magnetic field applying unit of the drive source unit and the coil unit.

The rotational force is transmitted to the first elastic portion 120 as a force for twisting the coil portions 141 and 151 with each axis along the Y-axis direction as the central axis, and as shown in FIG. 13, the first elastic portion 120a-1. , Coil portion 151, first elastic portion 120b2-2, second base portion 110-2 (including mirror 130, second elastic portion 120a-2, 120a-2) first elastic portion 120b-1, coil portion 141, The first elastic portions 120c-1 are connected to generate a steady wave-like coupled vibration. Then, this coupled vibration changes the resonance frequency of the mirror 130 and increases the rotational amplitude.

The principle of the resonance rotation of the mirror 130 and the increase of the rotational amplitude here is the same as that of the first embodiment, but the difference from the first embodiment is that the coil portions 141 and 151 are arranged symmetrically with the mirror 130 in between. That is. Therefore, the position of the node, which is the center of the coupled vibration, coincides with the center of the mirror. Therefore, it is possible to easily form a suitable standing wave-shaped coupled vibration.

In this embodiment, the movement of the right coil portion 141 is set as an example in which a rotational force is applied to the coil similar to that in the first embodiment. Needless to say, the rotation, vertical movement, left-right movement, Relative movement or other movement may be used. Similarly, the coil 151 may be a type other than the type in which a rotational force is applied to the coil portion, or may be a combination of left and right drive modes separately. Needless to say, the left and right coils may have the same shape.

In particular, in the fifth embodiment, since the coil portions are arranged symmetrically with the mirror 130 sandwiched between them, the vibration mode of the coupled vibration is symmetrical with respect to the mirror 130, so that the position of the node of the mirror 130 can be easily adjusted. There is. In other words, by arranging the mirrors symmetrically, it is possible to form a coupled mode in which nodes naturally appear at the center position of the mirror.

Also in this embodiment, the coil portion 141 and the coil portion 151 do not directly rotate the mirror 130, but the exciting force (rotation, vertical movement, horizontal movement, relative movement, etc.) is used as an energy source for coupled vibration in the coil portion. The mirror 130 is resonantly driven by adding other movements).
Therefore, the MEMS mirror driving device 104 of the fifth embodiment can preferably enjoy various effects as in the first to fourth embodiments.
(6) Sixth Example A sixth embodiment of the MEMS mirror driving device will be described with reference to FIGS. 14 and 15.
(6-1) Basic configuration and operation

FIG. 14 is a plan view conceptually showing the basic configuration and operation of the MEMS mirror driving device 105 of the sixth embodiment. FIG. 15 is a side view conceptually showing the basic operation of the MEMS mirror driving device 105 of the sixth embodiment. The same configuration as the MEMS mirror driving device 100 of the first embodiment described above will be designated by the same reference numerals, and detailed description thereof will be omitted.

The sixth embodiment is an example in which the drive source unit 160 is added to have two coil units and arranged on both sides of the mirror 130 as compared with the first embodiment. The right drive source unit 140 is a drive source unit that is responsible for rotation about an axis along the Y-axis direction, and the magnetic poles are 142c to 142f. The drive source unit 160 is a drive source unit that is responsible for rotation about an axis along the direction of the X axis, and the magnetic poles are 162a and 162b. In this embodiment, the movement of the coil portion 141 is set as an example in which a rotational force is applied to the coil portion similar to that in the first embodiment, but it goes without saying that the coil portions shown in the second to fourth embodiments are subjected to. Vertical movement, left-right movement, relative movement, etc. may be given. Further, the shape of the coil portion may be any shape as in the first embodiment.

Due to this configuration, in the operation of this embodiment, the left coil portion 161 is driven to rotate around the axis along the X-axis direction, and the right coil portion 141 is driven in the Y-axis direction. It is responsible for the resonance drive of rotation around the axis along the axis.

First, with reference to FIG. 14, regarding the MEMS mirror driving device 105 of the sixth embodiment, the rotation operation about the axis along the X-axis direction of the mirror 130 as the central axis will be described.
A counterclockwise current in the figure is applied to the coil unit 161 at a desired timing from a drive source unit control circuit (not shown), and an electromagnetic interaction occurs between the coil unit 161 and the magnetic poles 162a and 162b. As a result, electromagnetic force is generated due to electromagnetic interaction.

Here, the direction of the electromagnetic force due to the electromagnetic interaction between the coil portion 161 and the magnetic pole 162a is from the back side (back side of the paper surface) to the front side (front side of the paper surface) in FIG. The direction of the electromagnetic force due to the electromagnetic interaction between the coil portion 161 and the magnetic pole 162b is from the front side to the back side in FIG. As a result, this electromagnetic force is generated in the first elastic portion 120a- with the extension direction (direction along the X axis) of the first elastic portions 120a-1, 120b2-1, 120b-1 and 120c-1 as the rotation axis direction. 1, 120b2-1, 120b-1 and 120c-1 are rotated, and the coil portion 161 is rotated. As a result, the second base portion 110-2 rotates about the axis along the X-axis direction as the central axis, and the mirror 130 supported by the second base also has the axis along the X-axis direction as the central axis. Rotate as.

The second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130) performs a rotational operation at a frequency lower or higher than the mirror resonance frequency described later within a predetermined angle range. May be repeated with. For example, when the MEMS mirror driving device 105 of the sixth embodiment is applied to a display (or a head-mounted display), the second base portion 110-2 (second elastic portions 120a-2, 120b-2 and the mirror 130) (Including) may repeat the rotation operation at a frequency (for example, 60 Hz) corresponding to, for example, the scanning cycle or the frame rate of the display.

Alternatively, the second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130) may be the second base portion 110-2 (the second elastic portions 120a-2, 120b-2 and the mirror). The rotation operation at a resonance frequency determined by the suspended portion such as the coil portion 160 (including 130) and the first elastic portion 120 may be repeated within a predetermined angle range. Strictly speaking, the resonance frequency is a value that takes into account the springiness, inertial mass, and other effects of the coil portion 140 around the X-axis, but is omitted here.

Next, the operation related to rotation (resonance drive) about the axis of the mirror 130 along the Y-axis direction will be described. FIG. 15 is a side view conceptually showing a mode of operation by the MEMS mirror driving device 105 according to the sixth embodiment. (The magnetic poles 162a and 162b are omitted.) During the operation of the MEMS mirror drive device 100 of the sixth embodiment, the coil unit 141 is supplied with a desired control current at a desired timing from a drive source unit control circuit (not shown). Is applied.

The control current includes a current component for rotating the mirror 130 with an axis along the Y-axis direction as a rotation axis.

Here, as shown in FIG. 14, a control current flowing in the counterclockwise direction is supplied to the coil unit 141, and a magnetic field from the magnetic poles 142c and 142d to the magnetic poles 142e and 142f is applied to the coil unit 141. .. By applying an electric current to the coil portion 141, an electromagnetic interaction occurs between the coil portion 141 and the magnetic pole 142c magnetic pole 142d, magnetic pole 142e and 142f.

As a result, electromagnetic force is generated due to electromagnetic interaction. The direction of the electromagnetic force due to the electromagnetic interaction between the coil portion 141 and the magnetic poles 142c and 142d is from the back side (back side of the paper surface) to the front side (front side of the paper surface) in FIG. The direction of the electromagnetic force due to the electromagnetic interaction between the coil portion 141 and the magnetic poles 142e and 142f is from the front side to the back side in FIG.

Therefore, an electromagnetic force acting as a couple is generated on the two long sides 141a and 141b of the coil portions 141 facing each other along the X-axis direction. Therefore, the coil portion 141 rotates in the clockwise direction in FIG.

On the other hand, since the control current is an alternating current, the control current flowing in the clockwise direction is supplied to the coil unit 141 after a half cycle. Therefore, the coil portion 141 rotates in the counterclockwise direction in FIG.

Due to such an electromagnetic force, the coil portion 141 repeatedly rotates about an axis along the Y-axis direction as a rotation axis. The repetitive rotational force of the coil portion 141 is transmitted to the first elastic portion 120, the second base portion 110-2 and the coil portion 160 as the repetitive torsional force of the coil portion 141 with the axis along the Y-axis direction as the central axis, which will be described later. Generates a steady wave-like coupled vibration.

At this time, the rotation axis of the coil portion 141 along the Y-axis direction is different from the rotation axis of the mirror 130 along the Y-axis direction. Specifically, the rotation axis of the coil portion 141 along the Y-axis direction exists at a position shifted by a predetermined distance in the X-axis direction with reference to the rotation axis of the mirror 130 along the Y-axis direction. Therefore, the rotation of the coil portion 141 with the axis along the Y-axis direction as the rotation axis does not directly rotate the mirror 130 with the axis along the Y-axis direction as the rotation axis. In other words, the coil portion 141 is coupled to rotate the mirror 130, which will be described later, instead of applying a force that gives a twist in the rotation direction to the mirror 130 (supported by the second base portion 110-2) itself. A vibrating force is applied as an energy source for vibration.

Subsequently, the coupled vibration (coupling resonance) between the standing wave-shaped second base portion and the coil portion will be described with reference to FIG. Due to the repetitive rotational force generated by the coil portion 141, the first elastic portion 120a-1, the coil portion 161 and the first elastic portion 120b2-1, the second base portion 110-2 (second elastic portions 120a-2, 120b-2). The first elastic portion 120b-1, the coil portion 141, and the first elastic portion 120c-1 are connected to each other and deform and vibrate in a steady wave shape along the other direction, resulting in resonance vibration. In other words, the first elastic portion 120a-1, the coil portion 161 and the first elastic portion 120b2-1, the second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130), the first The 1 elastic portion 120b-1, the coil portion 141, and the 1st elastic portion 120c-1 are connected to each other and deform and vibrate so as to undulate along the X-axis direction like a quadruple mode of a string. That is, the first elastic portion 120a-1, the coil portion 161, the first elastic portion 120b2-1, the second base portion 110-2 (including the second elastic portions 120a-2, 120b-2, and the mirror 130), the first. The elastic portion 120b-1, the coil portion 141, and the first elastic portion 120c-1 exhibit deformation vibration such that a part thereof becomes a antinode of the coupled vibration and the other part becomes a node of the coupled vibration.

Due to the coupled vibration, the mirror 130 is rotated.
That is, the rotational resonance of the mirror 130 and the coupled vibration of the standing wave-shaped second base portion and the coil portion occur at the same frequency.
More strictly speaking, the resonance frequency of the mirror 130 is changed by the coupled vibration of the second base portion and the coil portion, and as a result, the mirror 130 has a frequency different from the resonance frequency determined by the mirror 130 and the second elastic portion. Resonates with. The resonance frequency of the mirror 130 at this time is typically slightly higher than the resonance frequency determined by the mirror 130 and the second elastic portion. Further, at this time, the rotation angle of the mirror 130 tends to be larger than that in the case where the frequency is not changed due to the coupled vibration.

Here, the rotation of the coil portion 141 having the axis along the Y-axis direction as the rotation axis, and the steady wavy shape of the first elastic portion 120, the coil portion 161 and the second base portion and the coil portion 141 along the X-axis direction. The relationship between the coupled vibration and the rotation of the mirror 130 with the axis along the Y-axis direction as the rotation axis will be described in more detail with reference to FIG.

In the above-mentioned coupled vibration as shown in FIG. 15, the center of the coil portion 141 is at the node position. The center of the second base portion 110-2, that is, the center of rotation of the mirror 130, and the center of the rotation axis of the second elastic portion is a node. The first elastic portions 120a-1, 120b-1, and 120c-1 are in the abdominal position. That is, the coil portion 141 is located at the node position in the standing wave wave, and the form of the force generated by the coil portion 141 matches the movement of the coil portion 141 in the coupled vibration. Since the mirror 130 is located at the node position, it does not move up and down in the drawing, and only rotates around the rotation axis along the direction of the Y axis, so that the mirror 130 can efficiently enjoy the rotational force and rotate. The above-mentioned coupled vibration shows a so-called standing wave-like deformed state, and the positions of its antinodes and nodes are substantially fixed. However, the fact that the mirror 130 or the coil portion 141 is located at the node position does not mean that the mirror 130 or the coil portion 141 is exactly located, but it may be interpreted that the mirror 130 or the coil portion 141 is located near the node. It is better to think that the closer it is to the knot, the more efficiently it rotates.

Further, in the above-mentioned coupled vibration, there is a mirror 130 (second base portion 110-2) at the center, and coil portions 161, 141 are located on both sides thereof, and each member, that is, the first elasticity is centered on the mirror 130. Part 120a-1, coil part 161, first elastic part 120b2-1, second base part 110-2 (including second elastic parts 120a-2, 120b-2 and mirror 130), first elastic part 120b-1 , The coil portion 141, and the first elastic portion 120c-1 are arranged in a point-symmetrical manner. Therefore, it becomes easy to match the position of the center of the mirror, which is the center, with the position of the node.

In order to realize the above-mentioned coupled vibration, the first elastic portion 120a-1, the coil portion 161 and the first elastic portion 120b2-1, the second base portion 110-2 (second elastic portions 120a-2, 120b-2). And the mirror 130), the rigidity, mass, length, width, shape, etc. of the first elastic portion 120b-1, the coil portion 141, and the first elastic portion 120c-1 are adjusted. Specifically, the length, width, shape, cross-sectional shape, rigidity of the first elastic portion, the shape, mass, rigidity of the second base portion 110-2, the shape, mass, rigidity, etc. of the coil portions 141, 161 are adjusted. You may. By adjusting these, the positions and frequencies of the nodes and antinodes become appropriate, the above-mentioned coupled vibration is preferably realized, and suitable rotation of the mirror 130 is realized.

As shown in FIG. 15, typically, the movements of the second base portion 110-2 and the mirror 130 are opposite to each other, so that the rotation direction of the coil portion 141 and the rotation direction of the mirror 130 are the same as each other. It will be oriented. However, the above-mentioned resonance mode is an example, and may be another resonance mode (for example, a mode in which the second base and the mirror are oriented in the same direction, or a higher-order mode having more nodes).

Also in this embodiment, the operation related to rotation about the rotation axis in the direction along the X axis of the mirror 130 is driven by a direct torsional force as in the first embodiment, but in the direction along the Y axis. Regarding the operation related to the rotation around the rotation axis of the above, the coil unit 141 does not directly rotate the mirror 130, but is vibrated to the coil unit 141 as an energy source of coupled vibration for rotating the mirror 130. Apply force.
Therefore, the MEMS mirror driving device 105 of the sixth embodiment can preferably enjoy various effects as in the first embodiment.

(7) Seventh Example A seventh embodiment of the MEMS mirror driving device will be described with reference to FIG.
(7-1) Basic configuration

FIG. 16 is a plan view conceptually showing the basic configuration of the MEMS mirror driving device 106 of the seventh embodiment. In the seventh embodiment, an electrostatic drive method is adopted, and the attractive force of the electrostatic electrode is used. The basic configuration is the same as that of the first embodiment except that the electrostatic force is used instead of the electromagnetic force.
The same configuration as the MEMS mirror driving device 100 of the first embodiment described above will be designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 16, in the MEMS mirror driving device 106 of the seventh embodiment, the first base portion 110-1, the first elastic portions 120a-1, 120b-1 and 120c-1, and the second base portion 110 -2, second elastic portions 120a-2 and 120b-2, a mirror 130, a movable electrode portion 170 having movable electrodes 171a and 171b, and fixed electrodes 172a and 172b.

The movable electrode portion 170 constituting the drive source portion 140 is arranged apart from the second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130), and is arranged on the first elastic portion 120. Is placed in. In other words, the movable electrode portion 170 is connected to and arranged in the second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130) with the first elastic portion 120b-1 sandwiched between them. Will be done.
The fixed electrodes 172a and 172b are directly or indirectly fixed to the first base portion 110-1.

As shown in FIG. 16, the movable electrode 171a and the fixed electrode 172a are arranged on the upper right side of the drive source unit 140, and the movable electrode 171b and the fixed electrode 172b are arranged on the lower left side of the drive source unit 140. Due to the electrostatic attraction generated by the drive source unit 140, the movable electrode unit 170 can generate two rotational forces, an axial couple along the X-axis and an axial couple along the Y-axis.
(7-2) Operation of MEMS mirror drive device

Subsequently, the rotation operation about the axis along the X-axis direction and the axis along the Y-axis direction will be described. Since the basic operation mode is the same as that of the first embodiment, details will be omitted.

A voltage of opposite polarity is applied to the movable electrode 171a and the fixed electrode 172a at a desired timing from a drive source unit control circuit (not shown). Therefore, an electrostatic attractive force is generated, and an attractive force is generated on the movable electrode 171a and the fixed electrode 172a. For example, after a half cycle, voltages of opposite polarities are applied to the movable electrode 171b and the fixed electrode 172b at a desired timing from a drive source unit control circuit (not shown). Therefore, an attractive force is generated in the movable electrode 171b and the fixed electrode 172b. Therefore, a repetitive rotational force is generated in the movable electrode portion 170 due to the electrostatic attraction force that is alternately generated every half cycle. Therefore, as in the first embodiment, a rotational force around the axis along the X-axis direction is generated in the mirror 130, and the mirror 130 rotates with the axis along the X-axis direction as the rotation axis.

A voltage of opposite polarity is applied to the movable electrode 171a and the fixed electrode 172a at a desired timing from a drive source unit control circuit (not shown). Therefore, an electrostatic attractive force is generated, and an attractive force is generated between the movable electrode 171a and the fixed electrode 172a. After half a cycle, voltages of opposite polarities are applied to the movable electrode 171b and the fixed electrode 172b at a desired timing from a drive source unit control circuit (not shown). Therefore, an attractive force is generated in the movable electrode 171b and the fixed electrode 172b. Therefore, a repetitive rotational force is generated in the movable electrode portion 170 due to the electrostatic attraction force that is alternately generated every half cycle. Therefore, as in the first embodiment, a rotational force around the axis along the Y-axis direction is generated in the mirror 130, and this force repeatedly rotates with the axis along the Y-axis direction as the rotation axis.

The repetitive rotation is transmitted to the first elastic portion 120 and the second base portion 110-2 as repetitive vibration of the movable electrode portion 170 about the axis along the Y-axis direction, and the first elastic portion 120a-. 1. The second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130), the first elastic portion 120b-1, the movable electrode portion 170, and the first elastic portion 120c-1 are In succession, it deforms and vibrates in a standing wave shape along the Y-axis direction, resulting in resonance.

Similar to the first embodiment, the mirror 130 rotates due to the standing wave-like deformation vibration, in other words, the standing wave-like coupled vibration. As a further aspect, the resonance frequency of the mirror 130 may be different from the resonance frequency determined by the mirror 130 and the second elastic portion 120-2. In other words, the first elastic portion 120a-1, the second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130), the first elastic portion 120b-1, and the movable electrode portion 170. , And the resonance frequency of the mirror 130 may be changed by the coupled vibration with the first elastic portion 120c-1.

Needless to say, the form of the driving force is not limited to the rotational force, and vertical movement, left-right movement, relative movement, and other forms of the driving force may be used. Further, it may be used in combination with electromagnetic force and pressure power, or a plurality of drive sources may be used.

Also in this embodiment, the drive source unit 140 does not directly rotate the mirror 130 with respect to the rotation around the axis of the mirror 130 along the Y axis, and the drive source unit 140 serves as an energy source for coupled vibration. Apply vibration force. Therefore, the MEMS mirror driving device 106 of the seventh embodiment can preferably enjoy various effects as in the first embodiment.
(8) Eighth Example An eighth embodiment of the MEMS mirror driving device will be described with reference to FIGS. 17 and 18.
(8-1) Basic configuration

The MEMS mirror driving device 107 of the eighth embodiment will be described with reference to FIG. FIG. 17 is a plan view conceptually showing the basic configuration of the MEMS mirror driving device 107 of the eighth embodiment. Since the basic configuration and operation other than the method of generating the driving force by compressing and expanding by the piezoelectric element instead of the electromagnetic force are the same as those in the second embodiment, they will be omitted. Further, the same configuration as that of the MEMS mirror driving device 101 of the second embodiment described above will be designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 17, the MEMS mirror driving device 107 of the eighth embodiment includes the first base portion 110-1 and the first elastic portions 120a-1, 120b-1 and 120c-1 (120c1a, 120c1b). It includes a second base portion 110-2, second elastic portions 120a-2 and 120b-2, a mirror 130, and a piezoelectric portion 180.

The piezoelectric portion 180 constituting the drive source portion 140 is arranged apart from the second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130), and is arranged on the first elastic portion 120. Is placed in. In other words, the piezoelectric body portion 180 is connected to and arranged in the second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130) with the first elastic portion 120b-1 sandwiched between them. Will be done.

The first elastic portion 120c-1 is composed of 120c-1a and 120c-1b. Piezoelectric bodies are provided on the surfaces of 120c-1a and 120c-1b, and displacement in the direction warping in the Z-axis direction can be generated by the principle of bimetal. The 120c-1a and 120c-1b are configured to be displaced in opposite directions along the Z axis by applying a voltage.

The piezoelectric body portion 180 has a rectangular flat plate shape, and the piezoelectric body 181 is provided on the surface thereof. By applying a voltage, as shown in FIG. 17, compression and expansion are performed along the X-axis direction, and as a result, the piezoelectric body portion 180 can be warped. Needless to say, the shape of the piezoelectric part 180 is not limited to a rectangle, and may be a square, a circle, an ellipse, a polygon, a donut shape, or any other shape. The piezoelectric element is not limited to the piezoelectric film on the surface, and piezoelectric ceramics are used. It may be formed by a coating type, a vapor deposition type, or any other method.
(8-2) Operation of MEMS mirror drive device

Subsequently, the rotation operation about the axis along the X-axis direction and the axis along the Y-axis direction will be described with reference to FIG. Since the basic operation mode is the same as that of the second embodiment, the details will be omitted.

A desired voltage is applied to the piezoelectric bodies provided on the surfaces of the first elastic portions 120c-1a and 120c-1b at a desired timing from a drive source portion control circuit (not shown). Due to the piezoelectric effect, forces in opposite directions act along the Z-axis direction on the two connecting portions of the first elastic portions 120c-1a and 120c-1b of the piezoelectric portion 180. Therefore, a rotational force is generated in the piezoelectric body portion 180 with the axis along the X-axis direction as the central axis, the piezoelectric body portion 180 rotates, and the mirror 130 also rotates with the axis along the X-axis direction as the central axis. ..

A desired voltage is applied to the piezoelectric body 181 provided in the piezoelectric body unit 180 at a desired timing from a drive source unit control circuit (not shown). Due to the piezoelectric effect, for example, the piezoelectric body 181 is compressed. Therefore, as shown in FIG. 18, the piezoelectric body portion 180 generates a warp with a concave top.
On the other hand, since the control voltage is an AC voltage, a voltage in the opposite direction is applied after half a cycle, and the piezoelectric body 181 is stretched. Therefore, as shown by the dotted line in FIG. 17, the piezoelectric body portion 180 generates a warp with a concave bottom. Such a repetitive operation becomes vibration and becomes a vibration source that generates resonance.

Then, the repetitive motion is transmitted to the first elastic portion 120 and the second base portion 110-2, and the first elastic portion 120a-1 and the second base portion 110-2 (second elastic portions 120a-2, 120b-2). The first elastic portion 120b-1, the piezoelectric portion 180, and the first elastic portion 120c-1 are connected to each other and deform and vibrate in a standing wave shape along the Y-axis direction, resulting in resonance.

Similar to the second embodiment, the mirror 130 rotates due to the standing wave-like deformation vibration, in other words, the standing wave-like coupled vibration. As a further aspect, the resonance frequency of the mirror 130 may be different from the resonance frequency determined by the mirror 130 and the second elastic portion 120-2. In other words, the first elastic portion 120a-1, the second base portion 110-2 (including the second elastic portions 120a-2, 120b-2 and the mirror 130), the first elastic portion 120b-1, and the movable electrode portion 170. , And the resonance frequency of the mirror 130 may be changed by the coupled vibration with the first elastic portion 120c-1.

Needless to say, the deformed shape is not limited to the vertical movement of the piezoelectric body portion 180, and rotational movement, left-right movement, relative movement, and other deformed shapes may be used. Further, it may be used in combination with electromagnetic force and electrostatic force, or a plurality of drive sources may be used.

Also in this embodiment, regarding the rotation of the mirror 130 around the axis along the Y axis, the drive source unit 140 does not directly rotate the mirror 130, but the drive source unit 140 (as an energy source for coupled vibration). The piezoelectric part 180) applies a vibrating force. Therefore, the MEMS mirror driving device 107 of the eighth embodiment can preferably enjoy various effects as in the first embodiment and the second embodiment.

The MEMS mirror driving device 100 of the first embodiment to the MEMS mirror driving device 107 of the eighth embodiment described above may be, for example, a head-up display, a head-mounted display, a retinal scanning display, a laser scanner, or a laser printer. It can also be applied to various electronic devices such as scanning type drive devices. Therefore, these electronic devices are also included in the scope of the present invention.
Further, the present invention can be appropriately modified within a range not contrary to the gist or idea of the invention which can be read from the claims and the entire specification, and the driving device accompanied by such a modification is also included in the technical idea of the present invention. Is done.

101-105 MEMS mirror drive device 110-1 1st base part 110-2 2nd base part 120 1st elastic part 120-2 2nd elastic part 120a-1, 120b-1, 120b2-1, 120c-1 1st Elastic part 120c-1a, 120c-1b 1st elastic part 120a-2, 120b-2 2nd elastic part 130 Mirror 140 Drive source part 141 Coil part 142a, 142b, 142c, 142d, 142e, 142f Magnetic pole 150 Drive source part 151 Coil part 152a, 152b, 152c, 152d, 152e, 152f Pole 160 Drive source part 161 Coil part 162a, 162b Pole 170 Movable electrode part 171a, 171b Movable electrode 172a, 172b Fixed electrode 180 Hydraulic body part 181

Claims (15)

The first base portion, the second base portion supported by the first base portion, the first base portion and the second base portion are connected, and the second base portion is oriented in another direction. A first elastic portion having elasticity to rotate the shaft as a rotation axis, a drive source portion arranged on the first elastic portion away from the second base portion, and a rotatable driven portion. A second elastic portion that connects the second base portion and the driven portion and has elasticity to rotate the driven portion with an axis along one direction different from the other direction as a rotation axis. The driven unit resonates with the axis along the one direction as a rotation axis due to the periodic excitation force from the drive source unit , and the movable connection portion of the drive source unit and the second base. The unit is unilaterally connected to the unit via the first elastic portion, and the drive source unit has a movable electrode or a piezoelectric body. The first base portion, the second base portion supported by the first base portion, the first base portion and the second base portion are connected, and the second base portion is oriented in another direction. A first elastic portion having elasticity to rotate the shaft as a rotation axis, a drive source portion arranged on the first elastic portion away from the second base portion, and a rotatable driven portion. A second elastic portion that connects the second base portion and the driven portion and has elasticity to rotate the driven portion with an axis along one direction different from the other direction as a rotation axis. The first elastic portion, the second base portion, and the drive source portion deform and vibrate in a steady wave shape along the other direction due to the periodic excitation force from the drive source portion, and the steady wave. Due to the deformed vibration of the shape, the driven portion rotates about an axis along the one direction as a rotation axis, and the movable connection portion of the drive source portion and the second base portion are connected to the first elastic portion. are connected one-dimensionally via the drive unit is to have a movable electrode or the piezoelectric resonant frequency of the driven unit, and characterized in that the transition by the deformation vibration of the standing wave form Drive device. The driving device according to claim 2, wherein the resonance frequency of the driven portion coincides with the resonance frequency of the standing wave-shaped deformed vibration. The driving device according to any one of claims 2 and 3, wherein the resonance frequency of the driven portion is higher than the resonance frequency determined by the driven portion and the second elastic portion. The driving device according to any one of claims 2 and 3, wherein the resonance frequency of the driven portion is lower than the resonance frequency determined by the driven portion and the second elastic portion. The drive device according to any one of claims 1 to 5, wherein the drive source unit is a single drive source unit. The drive device according to any one of claims 1 to 6, wherein a second drive source portion is provided on the first elastic portion, and the drive source portions are arranged on both sides of the driven portion. .. A drive source unit that applies a periodic excitation force to rotate the driven unit with an axis along the one direction as a rotation axis, and a drive source unit that rotates the driven unit with an axis along the other direction as a rotation axis. The drive device according to claim 7, further comprising a drive source unit for applying a vibrating force for causing the vehicle to be driven. The first base portion, the second base portion supported by the first base portion, the first base portion and the second base portion are connected, and the second base portion is oriented in another direction. A first elastic portion having elasticity to rotate the shaft as a rotation axis, a drive source portion arranged on the first elastic portion, a rotatable driven portion, the second base portion, and the driven portion. It is provided with a second elastic portion that is connected to the portion and has elasticity to rotate the driven portion with an axis along one direction different from the other direction as a rotation axis, and is provided from the drive source portion. The first elastic portion, the second base portion, and the drive source portion deform and vibrate in a steady wave shape along the other direction due to the periodic excitation force of the above, and the steady wave shape deformation vibration causes the said. The driven portion rotates about an axis along the one direction as a rotation axis, and the movable connection portion of the drive source portion and the second base portion are unilaterally connected via the first elastic portion. The driving device is characterized in that the driving source portion has a movable electrode or a piezoelectric body, and the resonance frequency of the driven portion is changed by the steady wavy deformation vibration. The driving device according to claim 9, wherein the resonance frequency of the driven portion is changed by the standing wave-shaped deformation vibration and coincides with the resonance frequency of the standing wave-shaped deformation vibration. The resonance frequency of the driven portion is higher than the resonance frequency determined by the driven portion and the second elastic portion by being transitioned by the stationary wave-shaped deformation vibration, according to claims 9 and 10. The driving device according to any one item. The resonance frequency of the driven portion is lower than the resonance frequency determined by the driven portion and the second elastic portion due to the transition by the steady wave-like deformation vibration, according to claims 9 and 10. The driving device according to any one item. The drive device according to any one of claims 9 to 12, wherein the drive source unit is a single drive source unit. The drive device according to any one of claims 9 to 13, wherein a second drive source portion is provided on the first elastic portion, and the drive source portions are arranged on both sides of the driven portion. .. A drive source unit that applies a periodic excitation force to rotate the driven unit with an axis along the one direction as a rotation axis, and a drive source unit that rotates the driven unit with an axis along the other direction as a rotation axis. The drive device according to claim 14, further comprising a drive source unit for applying a vibrating force for causing the vehicle to rotate, and a drive source unit for applying an exciting force.

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