JP2023000488A - Mirror drive mechanism - Google Patents

Abstract

To provide a mirror drive mechanism which can suppress the image quality deterioration of an image to be drawn.SOLUTION: A mirror drive mechanism 11 comprises: a base part 12; a mirror part 14; and a support part 31. The support part 31 comprises: first portions 32a, 32b, 32c, 32d, 32e, 32f, 32g, 32h; second portions 33a, 33b, 33c, 33d, 33e, 33f, 33g, 33h; and a piezoelectric element. The mirror drive mechanism 11 comprises: coupling parts 41, 42 which couple the mirror part 14 with the support part 31; and a motion absorber 51 which is connected in the vertical direction to the center axis of oscillation via the coupling parts 41, 42. The motion absorber 51 comprises: spring parts 53a, 53b, 53c, 53d in the first thickness connected to the coupling parts 41, 42; and mass parts 52a, 52b which are connected to the spring parts 53a, 53b, 53c, 53d and include a region in the second thickness thicker than the first thickness.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to mirror drive mechanisms.

2. Description of the Related Art There are known optical scanning devices and image forming apparatuses that include mirrors and scan light by swinging the mirrors (see, for example, Patent Documents 1 and 2). Images such as characters and graphics can be drawn by scanning the light reflected by the mirror along a desired path using such an optical scanning device or image forming device.

JP 2017-9920 A JP 2016-27368 A

In the mirror drive mechanism for swinging the mirror section, a two-dimensional image can be drawn by setting the swing axes for swinging the mirror section to, for example, two orthogonal axes. At this time, considering the axis driven at the frame rate among the two orthogonal axes, the drawing time per unit time can be increased by changing the drive voltage from a sine wave to a sawtooth wave. Therefore, image brightness and resolution can be improved. In the sawtooth wave driving, when an image is drawn and light is scanned, if an unintended resonance vibration is excited in the supporting portion that oscillatably supports the mirror portion, the light cannot be scanned properly. For example, the image cannot be drawn at a constant speed during image scanning, resulting in deterioration in image quality such as unwanted unevenness in the image. Accordingly, one of the objects is to provide a mirror driving mechanism capable of suppressing deterioration of image quality of a drawn image.

A mirror driving mechanism according to the present disclosure includes a plate-like base portion having a through hole, a mirror portion disposed in the through hole, an inner wall surface of the base portion surrounding the through hole, and an outer edge of the mirror portion. and a plate-shaped support portion that supports the mirror portion so as to be able to swing. The support portion includes a plurality of first portions extending in a direction orthogonal to a central axis of swinging of the support portion and arranged parallel to each other, and adjacent ends of the first portions on one side in the longitudinal direction and on the other side. 2nd portions that alternately connect side ends; and a plurality of first portions that extend along the longitudinal direction of each of the first portions; a positioned piezoelectric element. The mirror drive mechanism includes a connecting portion that connects the mirror portion and the support portion, and a motion absorbing member that is connected via the connecting portion in a direction perpendicular to the central axis of swing. The dynamic absorber includes a spring portion of a first thickness connected to the connecting portion, and a mass portion connected to the spring portion and including a region of a second thickness greater than the first thickness.

According to the mirror drive mechanism described above, it is possible to suppress the deterioration of the image quality of the drawn image.

FIG. 1 is a schematic plan view showing a mirror driving mechanism according to Embodiment 1. FIG. FIG. 2 is a schematic cross-sectional view of the mirror drive mechanism according to Embodiment 1, taken along line II-II. FIG. 3 is a schematic diagram showing a simplified model of the damping structure. FIG. 4 is a graph showing frequency response curves. FIG. 5 is a graph showing the relationship between the dimensions of the dynamic absorbing material and non-linearity. FIG. 6 is a graph showing experimental results of sawtooth waves measured when no dynamic absorber is included. FIG. 7 is a graph showing experimental results of sawtooth waves measured in the first embodiment.

[Description of Embodiments of the Present Disclosure]
First, the embodiments of the present disclosure are listed and described. A mirror driving mechanism according to the present disclosure includes a plate-shaped base portion having a through hole, a mirror portion disposed in the through hole, an inner wall surface of the base portion surrounding the through hole, and an outer edge of the mirror portion. and a plate-shaped support portion that supports the mirror portion so as to be able to swing. The support portion includes a plurality of first portions extending in a direction orthogonal to a central axis of swinging of the support portion and arranged parallel to each other, and adjacent ends of the first portions on one side in the longitudinal direction and on the other side. 2nd portions that alternately connect side ends; and a plurality of first portions that extend along the longitudinal direction of each of the first portions; a positioned piezoelectric element. The mirror drive mechanism includes a connecting portion that connects the mirror portion and the support portion, and a motion absorbing member that is connected via the connecting portion in a direction perpendicular to the central axis of swing. The dynamic absorber includes a spring portion of a first thickness connected to the connecting portion, and a mass portion connected to the spring portion and including a region of a second thickness greater than the first thickness.

The inventors have studied a configuration capable of suppressing degradation of image quality of an image to be drawn. As a result, it was found that the deterioration of the image quality of the drawn image can be suppressed by adopting the following configuration.

By reducing the thickness of the support portion in the form of a plate, it is possible to increase the amount of deformation of the support portion while reducing the weight of the support portion, thereby increasing the amplitude of oscillation. In addition, by using a waveform such as a triangular wave or a sawtooth wave in which the voltage changes linearly in a large area as the waveform of the voltage to be supplied to the piezoelectric element, the range of oscillation amplitude that can be used for scanning with light can be increased. be able to. Employment of such a configuration is advantageous in terms of improving the light utilization efficiency. However, when a voltage having a triangular wave or a sawtooth wave is supplied to the piezoelectric element, a high-frequency component is included in the oscillation of the mirror and support due to one of the multiple resonance frequencies of the mirror driving mechanism. put away. In particular, in the first portion extending in the direction orthogonal to the center axis of the oscillation of the supporting portion, the oscillation at the resonance frequency of the oscillating portion including the mirror portion and the supporting portion and performing the oscillating motion is induced by the high-frequency component, During rocking, an unwanted vibration called unintended ringing occurs in the first portion. As a result, there is a problem that the image quality of the rendered image is degraded.

Here, in order to suppress the occurrence of this ringing, it is conceivable to control and supply the drive signal of the voltage applied to the piezoelectric element. However, such a method requires a shaping circuit for shaping the signal waveform, resulting in a complicated circuit configuration. Then, the size of the control circuit is increased, which is not preferable in terms of the structure of the mirror driving mechanism.

A mirror driving mechanism of the present disclosure includes a connecting portion that connects a base portion and a supporting portion, and a motion absorber that is connected in a direction perpendicular to the central axis of swinging via the connecting portion. The dynamic absorber includes a spring portion of a first thickness connected to the connecting portion, and a mass portion connected to the spring portion and including a region of a second thickness greater than the first thickness. By including such a dynamic absorbing material, the vibration damping function of the dynamic absorbing material can be exhibited, and generation of unnecessary vibration can be suppressed. Here, by making the spring portion having the first thickness thinner than the mass portion having the second thickness, the spring portion is positively deflected so that the mass portion can effectively damp vibrations. Therefore, it is possible to more reliably suppress the generation of unnecessary vibrations in the mirror section. As a result, it is possible to suppress the deterioration of the image quality of the drawn image.

In the mirror drive mechanism, the ratio of the mass of the dynamic absorber to the mass of the mirror portion may be 0.1 or more and 1.0 or less. By doing so, it is possible to reliably improve the damping function for the mirror section, taking into consideration the variation in the dimensions of the members constituting the mirror drive mechanism. By setting the ratio of the mass of the dynamic absorber to the mass of the mirror portion to be 0.3 or more and 0.5 or less, it is possible to more reliably improve the damping function for the mirror portion.

In the mirror drive mechanism described above, the mirror portion may be disc-shaped. The dynamic absorber may be arranged on the outer peripheral side of the mirror section with a gap from the outer edge of the mirror section. By arranging the motion absorbing member at such a position, interference between the mirror portion and the motion absorbing member can be easily avoided when the mirror portion swings. Therefore, it is possible to suppress the deterioration of the image quality of the drawn image more reliably.

[Details of the embodiment of the present disclosure]
Next, one embodiment of the mirror drive mechanism of the present disclosure will be described with reference to the drawings. In the following drawings, the same reference numerals are given to the same or corresponding parts, and the description thereof will not be repeated.

(Embodiment 1)
A mirror drive mechanism according to Embodiment 1 of the present disclosure will be described. FIG. 1 is a schematic plan view showing a mirror driving mechanism according to Embodiment 1. FIG. FIG. 2 is a schematic cross-sectional view of the mirror drive mechanism according to Embodiment 1, taken along line II-II.

1 and 2, mirror drive mechanism 11 in the present embodiment includes plate-like base portion 12, mirror portion 14, plate-like support portion 31, mirror portion 14 and support portion 31. A pair of connecting portions 41 and 42 connecting the . As shown in FIG. 1, the outer shape of the base portion 12 is rectangular when viewed in the thickness direction. The long side of the base portion 12 extends in the direction indicated by the arrow X in FIG. The short sides of the base portion 12 extend in the direction indicated by the arrow Y in FIG. The direction indicated by arrow X and the direction indicated by arrow Y are orthogonal. The base portion 12 has a first through hole 13 penetrating in the thickness direction. The thickness direction of the base portion 12 is the direction indicated by the arrow Z in FIG. The base portion 12 includes a first surface 12a positioned on one side in the thickness direction and a second surface 12b positioned on the other side in the thickness direction. In this embodiment, the mirror drive mechanism 11 is configured by a MEMS (Micro Electro Mechanical System).

The mirror drive mechanism 11 includes a mirror portion 14 arranged within the first through hole 13 . The mirror part 14 has a plate shape. The thickness of the mirror portion 14 is thinner than the thickness of the base portion 12 . Mirror section 14 includes mirror 15 . The mirror 15 has a mirror surface 15a that reflects light incident from outside the mirror driving mechanism 11 . The mirror 15 is disc-shaped. A metal such as aluminum is deposited on the mirror surface 15 a of the mirror 15 .

The mirror portion 14 has a second through hole 16 . A mirror 15 is arranged in the second through hole 16 . The mirror portion 14 includes a pair of shaft portions 17a and 17b. Each of the pair of shaft portions 17a and 17b has a thin rod shape. The pair of shafts 17a and 17b are arranged at positions rotated by 180 degrees about the center of the disk-shaped mirror 15 as viewed in the thickness direction of the base 12 . The pair of shaft portions 17 a and 17 b connect the inner wall surface 18 of the mirror portion 14 surrounding the second through hole 16 and the outer edge 19 of the mirror 15 respectively.

The mirror section 14 includes piezoelectric elements 21a, 21b, 21c, and 21d, which are piezoelectric elements. Each of the four piezoelectric elements 21a, 21b, 21c, and 21d has a rectangular outer shape when viewed in the thickness direction of the base portion 12. As shown in FIG. The piezo elements 21a, 21b, 21c, and 21d are arranged on one surface in the thickness direction of the plate-shaped mirror portion 14, which is the surface on which the mirror surface 15a is located in this embodiment. The piezo elements 21a and 21b are spaced apart in the X direction. The piezo elements 21c and 21d are spaced apart in the X direction. The piezo elements 21a and 21c are spaced apart in the Y direction. The piezo elements 21b and 21d are spaced apart in the Y direction. Wirings connected to the piezo elements 21a, 21b, 21c, and 21d are omitted from the drawing.

The support portion 31 supports the mirror portion 14 inside the first through hole 13 . The support portion 31 connects the inner wall surface 22 of the base portion 12 surrounding the first through hole 13 and the outer edge 23 of the mirror portion 14 . The support portion 31 supports the mirror portion 14 so as to swing. The central axis 24a of the swing is indicated by a dashed line in FIG. The swing central axis 24a extends in the X direction. A central axis 24 a of the swing passes through the center of the mirror 15 when viewed in the thickness direction of the base portion 12 .

The support portion 31 extends in a direction (Y direction) perpendicular to the center axis 24a of the swing, and includes a plurality of first portions 32a, 32b, 32c, 32d, 32e, 32f, 32g, and 32h arranged parallel to each other. , second portions 33a, 33b that alternately connect ends on one side and ends on the other side of the adjacent first portions 32a, 32b, 32c, 32d, 32e, 32f, 32g, 32h in the longitudinal direction, 33c, 33d, 33e, 33f. The support portion 31 includes a connecting portion 34a connecting the first portion 32a and the inner wall surface 22 of the base portion 12, a connecting portion 34b connecting the first portion 32d and the connecting portion 41, the first portion 32e and the base portion. 12, and a connecting portion 34d connecting the first portion 32h and the connecting portion 42. As shown in FIG. The support portion 31 has a meandering structure.

The support portion 31 includes piezo elements 36a, 36b, 36c, 36d, 36e, 36f, 36g, and 36h. Each of the piezo elements 36a, 36b, 36c, 36d, 36e, 36f, 36g, and 36h has a rectangular outer shape when viewed in the thickness direction of the base portion 12. As shown in FIG. The piezo elements 36a, 36b, 36c, 36d, 36e, 36f, 36g, and 36h each extend longitudinally in regions corresponding to the plurality of first portions 32a, 32b, 32c, 32d, 32e, 32f, 32g, and 32h, respectively. It is provided so as to extend along the direction. Piezo elements 36a, 36b, 36c, 36d, 36e, 36f, 36g, and 36h are arranged on one side in the thickness direction of each of the plurality of first portions 32a, 32b, 32c, 32d, 32e, 32f, 32g, and 32h. It is arranged on the located first surface 12a. Wirings connected to the piezo elements 36a, 36b, 36c, 36d, 36e, 36f, 36g, and 36h are also omitted from the drawing.

A pair of connecting portions 41 and 42 connect the mirror portion 14 and the support portion 31 . Each of the connecting portions 41 and 42 has a thin rod shape and is provided so as to extend in the X direction. The connecting portion 41 connects the outer edge 26 of the mirror portion 14 and the connecting portion 34b. The connecting portion 42 connects the outer edge 26 of the mirror portion 14 and the connecting portion 34d. The connecting portions 41 and 42 are arranged at positions rotated 180 degrees about the center of the disk-shaped mirror 15 as viewed in the thickness direction of the base portion 12 .

The motion absorbing member 51 is connected in a direction perpendicular to the swing central axis 24a via the connecting portions 41 and 42. As shown in FIG. The dynamic absorber 51 is arranged on the outer peripheral side of the mirror section 14 with a gap from the outer edge 26 of the mirror section 14 . A third through-hole 27 is formed between the mirror portion 14 and the dynamic absorber 51 at a location where the connecting portions 41 and 42 are arranged.

The dynamic absorber 51 includes mass portions 52a, 52b and spring portions 53a, 53b, 53c, 53d. Each of the spring portions 53a, 53b, 53c, and 53d has a rectangular shape when viewed in the thickness direction of the base portion 12, with the Y direction being the longitudinal direction. The spring portions 53 a and 53 b are connected to the connecting portion 41 . The spring portions 53a and 53b are arranged adjacent to each other in the Y direction with the connecting portion 41 interposed therebetween. The spring portions 53 c and 53 d are connected to the connecting portion 42 . The spring portions 53c and 53d are arranged adjacent to each other in the Y direction with the connecting portion 42 interposed therebetween. Each of the mass portions 52a and 52b has an arcuate shape when viewed in the thickness direction of the base portion 12 . Both ends of the mass portion 52a are connected to the spring portions 53a and 53c, respectively. Both ends of the mass portion 52b are connected to the spring portions 53b and 53d, respectively.

Each of the spring portions 53a, 53b, 53c, 53d has a _first thickness T1. Each mass portion 52a, 52b has a region of a _second thickness T2 that is thicker than the _first thickness T1. In this embodiment, _each of the mass portions 52a, 52b has a thickness T2 over its entire area.

Also, the ratio of the mass of the dynamic absorber 51 to the mass of the mirror portion 14 is 0.1 or more and 1.0 or less. In this embodiment, the ratio of the mass of the dynamic absorber 51 to the mass of the mirror section 14 is 0.44.

Here, the operation of swinging the mirror 15 in the mirror driving mechanism 11 will be briefly described. The voltages supplied to the piezoelectric elements 36a, 36b, 36c, 36d, 36e, 36f, 36g, and 36h respectively arranged in the adjacent first portions 32a, 32b, 32c, 32d, 32e, 32f, 32g, and 32h are alternately reversed. By setting the phase, the adjacent first portions 32a, 32b, 32c, 32d, 32e, 32f, 32g, and 32h can be deformed so as to alternately warp in opposite directions. The mirror section 14 swings about the central axis 24a of swinging due to the alternate warping of the first portions 32a, 32b, 32c, 32d, 32e, 32f, 32g, and 32h in opposite directions. The vibration frequency is selected from, for example, the frame rate of the image.

Also, in the mirror section 14, the voltages supplied to the piezo elements 21a, 21b, 21c, and 21d arranged so as to be adjacent to each other are alternately set in opposite phases, thereby deforming the mirror section 14, thereby deforming the shaft sections 17a and 17b. can be deformed in a twisting direction to swing the mirror 15 . The swing central axis 24b extends in the Y direction. A central axis 24 b of the swing passes through the center of the mirror 15 when viewed in the thickness direction of the base portion 12 . A central axis 24b of swinging passes through the center of the pair of shaft portions 17a and 17b. In the mirror drive mechanism 11 shown in FIG. 1 , when viewed in the thickness direction of the base portion 12 , the swing central axis 24 a and the swing central axis 24 b are perpendicular to each other and intersect at the center of the mirror 15 . The mirror 15 vibrates at the resonance frequency of the mirror section 14 determined by the structure of the mirror section 14 and the shaft sections 17a and 17b, which is higher than the frame rate.

The mirror drive mechanism 11 can swing the mirror 15 around a swing axis 24a extending in the X direction and a swing center axis 24b extending in the Y direction. Therefore, the mirror driving mechanism 11 can draw a two-dimensional image by reflecting the light incident from the outside on the mirror 15 for scanning.

Here, the mirror drive mechanism 11 includes the dynamic absorber 51 having the above configuration. By doing so, the damping function of the dynamic absorbing material 51 can be exerted to suppress generation of unnecessary vibrations. Here, since the spring portions 53a, 53b, 53c, and 53d with the _first thickness T1 are thinner than the mass portions 52a and 52b with the _second thickness T2, the spring portions 53a, 53b, 53c, and 53d are positively moved. Vibration damping by the mass portions 52a and 52b can be effectively performed by bending the mass portions 52a and 52b. Therefore, generation of unnecessary vibrations in the mirror section 14 can be suppressed more reliably. As a result, it is possible to suppress the deterioration of the image quality of the drawn image.

In this embodiment, the ratio of the mass of the dynamic absorber 51 to the mass of the mirror section 14 is 0.1 or more and 1.0 or less. By doing so, it is possible to reliably improve the damping function for the mirror section 14 in consideration of variations in the dimensions of the members constituting the mirror drive mechanism 11 . By setting the ratio of the mass of the dynamic absorber 51 to the mass of the mirror portion 14 to be 0.3 or more and 0.5 or less, the damping function for the mirror portion 14 can be improved more reliably.

In this embodiment, the mirror portion 14 is disc-shaped. The dynamic absorbing material 51 is arranged on the outer peripheral side of the mirror section 14 with a gap from the outer edge of the mirror section 14 . Therefore, interference between the mirror portion 14 and the motion absorbing member 51 can be easily avoided when the mirror portion 14 swings. Therefore, it is possible to suppress the deterioration of the image quality of the drawn image more reliably.

Here, a damping structure is considered assuming that a steady harmonic excitation F ₁ e ^jωt with an angular frequency of ω is added to the main system while the resonance drive of the device is excited. FIG. 3 is a schematic diagram showing a simplified model of the damping structure. Referring to FIG. 3, member 61a corresponds to mirror portion 14, and member 61b corresponds to dynamic absorber 51. As shown in FIG. Considering materials that can be used for MEMS devices, it is difficult to add a damping mechanism having a viscous resistance component such as a damper. X ₁ is the displacement from the natural length of the main spring, X ₂ is the displacement from the natural length of the secondary spring, t is the time, m ₁ is the mass of the main system, m ₂ is the mass of the slave system, k ₁ is the spring constant of the main system, k2 is the spring constant of the _secondary system, _xst is the deflection of the main system when F1 acts as _a static external force, _ωm is the natural angular frequency of the main system alone, ω Assuming that _a is the natural angular frequency of the slave system alone, the vibration response in this case is expressed by the following equations (1) and (2).

Here, if the relationship of the equations (3) and (4) below is satisfied, the frequency response curve is as shown in FIG.

FIG. 4 is a graph showing frequency response curves. In FIG. 4, the vertical axis indicates the displacement (X ₁ /xst) of the mirror section 14, and the horizontal axis indicates the angular frequency ratio (ω/ωa). In FIG. 4, when the mass of the mirror portion 14 is m ₁ and the mass of the dynamic absorber 51 is m ₂ , the line 62a shows the case where m ₂ /m ₁ is 0.01, and the line 62b shows the case where m ₂ /m Line 62c shows the case where ₁ is 0.1, line 62c shows the case where m ₂ /m ₁ is 0.5, and line 62d shows the case where m ₂ /m ₁ is 1.0. In FIG. 4, the point where ω/ωa=1 indicates the anti-resonance point. Referring to FIG. 4, the closer the ratio of the mass _m2 of the dynamic absorber 51 to the mass m1 of the mirror portion 14 to ₁ , the wider the range of frequencies that can be damped. Here, by setting the ratio m ₂ /m ₁ of the mass m ₂ of the dynamic absorber 51 to the mass of the mirror section 14 to be 0.1 or more and 1.0 or less, the damping function for the mirror section 14 can be more reliably performed. can be improved.

FIG. 5 is a graph showing the relationship between the dimensions of the dynamic absorbing material 51 and non-linearity. In FIG. 5, the horizontal axis indicates the dimension (μm) of the dynamic absorbing material 51, and the vertical axis indicates the non-linearity (%). Moreover, by setting m ₂ /m ₁ to 0.1 or more and 1.0 or less in FIG. More preferably, m ₂ /m ₁ =0.3 or more and 0.5 or less.

FIG. 6 is a graph showing experimental results of sawtooth waves measured when the dynamic absorber 51 is not included. FIG. 7 is a graph showing experimental results of sawtooth waves measured in the first embodiment. 6 and 7, the horizontal axis indicates elapsed time, and the vertical axis indicates amplitude. Here, the non-linearity is expressed by the maximum value P ₁ of the amplitude difference from the sawtooth wave/amplitude P ₂ of the sawtooth wave ×100 (%).

First, referring to FIG. 6, according to the mirror drive mechanism that does not include the dynamic absorber 51, the nonlinearity was 8.8 (%) in the experimental value. On the other hand, referring to FIG. 7, according to the mirror driving mechanism 11 of the first embodiment, the non-linearity was 4.1 (%) in the experimental value. Thus, according to the mirror driving mechanism according to the present disclosure, nonlinearity can be significantly improved.

(Other embodiments)
According to the above embodiment, the mirror section is disk-shaped. However, the outer shape of the mirror section is not limited to this, and may be elliptical when viewed in the thickness direction of the base section. may

Further, in the above _- described embodiment, the thickness of the entire mass portion is the thickness _T2 . It is good also as a structure which has.

It should be understood that the embodiments disclosed this time are illustrative in all respects and are not restrictive in any aspect. The scope of the present invention is defined by the scope of the claims rather than the above description, and is intended to include all modifications within the meaning and range of equivalents of the scope of the claims.

The mirror drive mechanism of the present disclosure can be applied particularly advantageously when suppression of deterioration in image quality of an image to be drawn is required.

11 mirror driving mechanism 12 base portion 12a first surface 12b second surface 13 first through hole 14 mirror portion 15 mirror 15a mirror surface 16 second through holes 17a and 17b shaft portions 18 and 22 inner wall surfaces 19 and 23 , 26 outer edges 21a, 21b, 21c, 21d, 36a, 36b, 36c, 36d, 36e, 36f, 36g, 36h piezo elements 24a, 24b center shaft 27 third through hole 31 support portions 32a, 32b, 32c, 32d, 32e, 32f, 32g, 32h first portions 33a, 33b, 33c, 33d, 33e, 33f, 33g, 33h second portions 34a, 34b, 34c, 34d connecting portion 35 surfaces 41, 42 connecting portion 51 dynamic absorbing material 52a, 52b Mass portions 53a, 53b, 53c, 53d Spring portions 61a, 61b Members 62a, 62b, 62c, 62d Line P ₁ Maximum value P ₂ Amplitude X, Y, Z Arrows m ₁ , m ₂ Mass X ₁ , X ₂ Displacement k ₁ , k ₂ spring constant xst deflection ω angular frequency ω _m , ω _a natural angular frequency

Claims (3)

A mirror driving mechanism,
a plate-like base portion having a through hole;
a mirror part including a mirror and arranged in the through hole;
a plate-shaped support portion that connects the inner wall surface of the base portion surrounding the through hole and the outer edge of the mirror portion and supports the mirror portion so as to be swingable;
The support part is
a plurality of first portions each extending in a direction orthogonal to the central axis of swinging of the support portion and arranged parallel to each other;
a second portion that alternately connects ends on one side and ends on the other side of the adjacent first portions in the longitudinal direction;
a piezoelectric element extending along the longitudinal direction of each of the plurality of first portions and arranged on a surface located on one side in the thickness direction in the region corresponding to the first portion;
The mirror driving mechanism is
a connection portion that connects the mirror portion and the support portion;
a motion absorbing member connected in a direction perpendicular to the center axis of the swing through the connecting portion,
The dynamic absorber is
a spring portion having a first thickness connected to the connecting portion;
a mass portion connected to the spring portion and including a region of a second thickness that is thicker than the first thickness. 2. The mirror drive mechanism according to claim 1, wherein the ratio of the mass of said dynamic absorbing material to the mass of said mirror portion is 0.1 or more and 1.0 or less. The mirror portion is disc-shaped,
3. The mirror driving mechanism according to claim 1, wherein said dynamic absorbing member is arranged on the outer peripheral side of said mirror section with a gap from the outer edge of said mirror section.

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