JP2001290099A - Galvano-mirror device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a galvano-mirror which can be miniaturized and driven by low-voltage. SOLUTION: The galvano-mirror device X1 is provided with a fixing part 1A having an internal space 1B, a moving part 10 turnaby supported in the internal space 1B with respect to the fixing part 1A through torsion bar parts 12a and 12b, a mirror part 15 formed on one surface 10a of the moving part 10, first and second electrode parts 14 and 16 provided in the one surface 10a of the moving part 10 and other surface 10b, respectively, and third and fourth electrode parts 22a, 22b, 31a and 31b opposed to the first and second electrode parts 14 and 16 in fixing part 1A. Moreover, the galvano-mirror device X1 is constituted so as to turn the moving part 10 by electrostatic force when the potential difference is given to at least one side between the first electrode part 14 and the third electrode parts 22a and 22b, and between the second electrode part 16 and the fourth electrode parts 31a and 31b, and a partial area in the one surface 10a of the moving part 10 is shared by the first electrode part 14 and the mirror part 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a galvanomirror device used in an optical disk device or the like to control the irradiation position of light on an information reading / writing object such as an optical disk. The present invention relates to an electrostatically driven galvanomirror device configured to rotate by electrostatic force.

[0002]

2. Description of the Related Art Conventionally, various types of galvanomirror devices of an electrostatic drive type have been proposed (for example, JP-A-5-119280 and JP-A-9-14603).
No. 4, Japanese Patent No. 4) and an example thereof is shown in FIGS. The galvanomirror device Y shown in these figures sandwiches the first member 5 in which the movable portion 52 is rotatably supported via the torsion bar portion 51 with respect to the frame portion 50 so that the second member 6 and the second The three members 7 are arranged, and have a rectangular parallelepiped shape as a whole. On one surface 52a of the movable portion 52, a mirror portion 53 having a high light reflectivity is provided at the center thereof, and a pair of first electrode portions 54a, 54b separated in a plane so as to sandwich the mirror portion 53 is provided. ing. On the other hand, on the other surface 52b of the movable portion 52, a pair of second electrode portions 55a and 55b separated in a plane is provided. Second member 6
Is provided with a through hole 60 for exposing the mirror portion 53, and each first electrode portion 54 is formed along the periphery of the through hole 60.
a, 54b, a pair of third electrode portions 61a, 61b
Is provided. The third member 7 includes the second electrode portions 55
a, 55b, a pair of fourth electrode portions 70a, 70b
Is provided.

In such a configuration, for example, when the movable portion 52 is rotated clockwise in FIG. 8, a potential difference is applied between the second electrode portion 55b and the fourth electrode portion 70b, so that Apply electrostatic attraction to
Alternatively or additionally, the first electrode portion 54
a and the third electrode portion 61a causes an electrostatic attraction due to the application of a potential difference. On the other hand, when rotating the movable portion 52 in the counterclockwise direction in FIG. 8, the movable portion 52 is rotated between the second electrode portion 55a and the fourth electrode portion 70a and between the first electrode portion 54b and the third electrode portion 54b.
An electrostatic attraction due to a potential difference is applied to at least one of the electrodes 61b.

[0004] By the way, not only the galvanomirror device Y having the above configuration but also a galvanomirror device configured as an electrostatic drive type is required to reduce the driving power. Here, as shown in the following equation (1), the rotation angle θ of the movable part 52 is proportional to the torque T acting on the movable part 52, and is inversely proportional to the torsional rigidity K _S of the torsion bar part 51. Then, as shown in the following equations (2) and (3), the torque T
Is proportional to the electrostatic force F acting between the electrode parts, that is, the square of the potential difference V applied between the electrode parts and the electrode area A. Therefore, in order to enable low voltage driving of the movable portion 52, it is necessary to secure a large area A of the electrode portion and to reduce the torsional rigidity K _S of the torsion bar portion 51.

[0005]

(Equation 1)

[0006]

SUMMARY OF THE INVENTION A galvanomirror device Y
Is used in an optical disk device or the like. From the viewpoint of miniaturization of the optical disk device, the galvanometer mirror device Y is used.
Also, miniaturization is required. For this reason, while there is a limit to the area of the movable part 52 that can be secured, the movable part 5
In order to secure a large area of 2, the length of the torsion bar 51 must be naturally reduced. Therefore, in order to reduce the torsional rigidity K _S of the torsion bar portion 51, it is necessary to reduce the cross-sectional area of the torsion bar portion 51. In this case, the support of the movable portion 52 may become unstable.

[0007] Particularly, in the galvanomirror device Y described above, such a problem appears more remarkably. That is,
A mirror portion 53 is formed at the center of the movable portion 52 and separated from each other in a plane so as to sandwich the mirror portion 53.
In the configuration in which the first and second electrodes 54a and 54b are formed, it is difficult to secure a large area for each of the first electrodes 54a and 54b because of the restrictions of the mirror 53. Therefore, if an attempt is made to secure a large area for each of the first electrode portions 54a and 54b, a problem arises in the support stability of the movable portion 52 as described above.
On the other hand, increasing the length of the torsion bar portion 51 while securing a large area for the first electrode portions 54a and 54b is against the demand for downsizing the galvanomirror device Y.

The present invention has been conceived under the circumstances described above, and it is an object of the present invention to provide a galvanomirror device capable of driving at a low voltage while responding to a demand for miniaturization. .

[0009]

DISCLOSURE OF THE INVENTION In order to solve the above problems, the present invention employs the following technical means.

That is, the galvanomirror device provided by the first aspect of the present invention has a fixed portion having an internal space and provided with a light passing portion allowing light to pass therethrough, and a pair of fixed portions with respect to the fixed portion. A movable portion rotatably supported in the internal space via the torsion bar portion, a mirror portion formed on a surface of the movable portion immediately below the light passing portion, and a surface of the movable portion and A first electrode unit and a second electrode unit respectively provided on the other surface;
A third electrode portion and a fourth electrode portion provided in regions of the fixing portion facing the first electrode portion and the second electrode portion, respectively, wherein the first electrode portion, the third electrode portion, And a galvanomirror device configured to rotate the movable portion by an electrostatic force when a potential difference is applied to at least one of the second electrode portion and the fourth electrode portion. A feature is that a part of the area on one surface of the movable part is shared by the first electrode part and the mirror part.

Here, "a part of the surface of the movable portion is shared by the first electrode portion and the mirror portion" means that the first electrode portion itself also has a function as a mirror portion. And a case where a mirror portion is separately formed so as to cover at least a partial region on the first electrode portion. The same applies to the case of "shared by the fixed portion electrode portion and the mirror portion" in a second aspect of the present invention described later.

In this manner, in the configuration in which the first electrode portion and the mirror portion share a partial area on one surface of the movable portion, the first electrode portion and the mirror portion are planarly arranged as in a conventional galvanometer mirror device. As compared with the separated configuration, the ratio of the first electrode portion on one surface of the movable portion can be increased. For example, it is also possible to form the first electrode portion over the entire area or substantially the entire area of one surface of the movable section. Therefore, it is possible to provide a galvanomirror device capable of ensuring a large area of the first electrode portion and driving at a low voltage. In addition, it is possible to reduce the planar area of the movable portion required to secure a desired electrostatic force, to achieve a reduction in the size of the galvanomirror device, and to lengthen the torsion bar portion. In this case, the cross-sectional area of the torsion bar required to secure a constant torsional rigidity can be increased, so that the support rigidity of the movable part can be increased.

As mentioned above, it is possible to make the first electrode part also have a function as a mirror part. However, when the first electrode part is formed of a metal conductor or the like, It is also assumed that it is difficult to secure the target reflectance (in some cases, more than 90%), and in that case, a mirror unit may be separately formed on the first electrode unit. The mirror portion is formed of a material having a high reflectance with respect to light (wavelength) to be reflected, for example, a dielectric layer. Also, in an optical disc device or the like, it is assumed that a blue light source and a red light source are used together as a light source. Therefore, in consideration of such a case, a region having a high dielectric constant for blue light is considered. Alternatively, the dielectric layer may be configured to have a plurality of regions having different dielectric constants, such as a region having a high dielectric constant for red light.

In a preferred embodiment, the first
The electrode portion is electrically connected to the second electrode portion, and the first electrode portion and the second electrode portion are connected via a wiring portion formed on one of the pair of torsion bar portions. Are simultaneously supplied with a voltage.

In such a configuration, since a voltage is simultaneously supplied to each of the first and second electrode portions by one wiring, the first electrode portion and the second electrode portion are driven separately. It is not necessary to separately form a wiring portion for each. Therefore, in the galvanomirror device of the present invention, downsizing can be achieved by simplifying the wiring.

[0016] In a second aspect of the present invention,
A fixed portion having an internal space and provided with a light passage portion allowing light to pass therethrough, and a movable portion rotatably supported in the internal space with respect to the fixed portion via a pair of torsion bar portions. A mirror portion formed in a region directly below the light passing portion on one surface of the movable portion; a movable portion electrode portion provided on one surface of the movable portion; and a mirror portion opposed to the movable portion electrode portion on the fixed portion. A fixed portion electrode portion provided in the region, and configured to rotate the movable portion by electrostatic force when a potential difference is applied between the movable portion electrode portion and the fixed portion electrode portion. A galvanomirror device, wherein a partial area on one surface of the movable portion is
A galvano mirror device is provided, which is shared by the movable portion electrode portion and the mirror portion.

In this galvanomirror device as well, the electrode section provided with the movable section and the mirror section also share a partial area on one surface of the movable section, and thus the galvano mirror according to the first aspect of the present invention described above. The same advantages as the mirror device can be enjoyed. That is, the ratio of the fixed portion electrode portion on one surface of the movable portion can be increased, and the size of the fixed portion electrode portion can be increased, and the movable portion can be reduced in size to achieve low voltage driving and downsizing while securing a large area. The device can be provided. Further, it is possible to increase the torsion bar portion, increase the cross-sectional area of the torsion bar portion necessary for securing a constant torsional rigidity, and increase the support rigidity of the movable portion.

Of course, also in the second aspect of the present invention, the fixed portion electrode portion is formed over the entire area or substantially the entirety of one surface of the movable portion, and the mirror portion is formed as a dielectric layer laminated on the fixed portion electrode portion. It may be formed. Further, the dielectric layer may be composed of a plurality of regions having different dielectric constants.

In the above galvanomirror device on either side, the electrode portions (first electrode portion, second electrode portion, movable portion electrode portion) provided on the movable portion are connected to the wiring portion. And a potential of + or-may be applied by conducting to a predetermined power supply via the power supply, or a zero potential may be applied to the electrode portion provided on the movable portion by grounding the wiring portion.

[0020] Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be specifically described below with reference to the drawings.

First, a first embodiment of a galvanomirror device according to the present invention will be described with reference to FIGS. Here, FIG. 1 is an exploded perspective view showing a first embodiment of the galvanomirror device according to the present invention, and FIG.
3 is a cross-sectional view of the galvanomirror device of FIG.

The galvanomirror X1 of the present embodiment is configured such that the first member 1 having the movable portion 10 is
The member 2 and the third member 3 are provided, and the movable portion 10 is rotatably suspended in the internal space 1B of the fixed portion 1A having a rectangular parallelepiped appearance.

The first member 1 is entirely formed of, for example, silicon or the like. The movable member 10 is supported by the frame portion 11 via first and second torsion bar portions 12a and 12b. A communication space 13 is provided around the part 10.

The movable portion 10 is formed in a rectangular plate shape having a thickness smaller than that of the frame portion 11, and is rotatable around the axis of each of the torsion bar portions 12a and 12b provided on the same axis. Have been. A first electrode portion 14 is formed over substantially the entire surface 10a of the movable portion 10, and a rectangular mirror portion 15 is formed at the center of the first electrode portion 14 by lamination. The mirror unit 15 is a region that reflects light traveling toward the galvanomirror device X1, and is configured as, for example, a dielectric layer. More specifically, for example, in a case where blue light having a wavelength of about 410 nm is efficiently reflected, ditantalum pentoxide (Ta ₂ O ₅ ) or titanium dioxide is formed on a silicon oxide film (SiO ₂ ). It is formed by laminating (TiO ₂ ) films. The total thickness of the first electrode section 14 and the mirror section 15 is about 7200 °.

On the other hand, the other surface 10b of the movable portion 10 has a second electrode portion 16 formed substantially over the entire surface.
A counterbalance film 17 which is a dielectric film of, for example, silicon oxide is formed at the center of the electrode portion 16.
The rigidity of the movable portion 10 is increased by the counterbalance film 17, and the movable portion 10 is prevented from warping.

The movable portion 10 is provided with a through hole 18a, and the inside of the through hole 18a is filled with a conductor 18b of, for example, solder or silver to form the first electrode portion 1a.
4 and the second electrode portion 16 are electrically connected. A wiring portion 19 connected to the first electrode portion 14 is provided on the upper surface of the first torsion bar portion 12a, and the first electrode portion 14 and the second electrode 16 are simultaneously connected to the wiring portion 19 via the wiring portion 19. The potential can be supplied.

The first electrode section 14, the second electrode section 16,
And wiring portion 19 is formed of, for example, gold or aluminum. Further, the wiring portion 19 may be formed on the lower surface side of the first torsion bar portion 12a. Alternatively, the first torsion bar portion 12a may be doped with an impurity to lower the resistivity, and the first torsion bar portion 12a itself may be formed. May be improved to a material through which current flows easily. The first electrode section 14 and the second electrode section 16 may be supplied with a + or-potential by conducting the wiring section 19 to a predetermined power supply, or may be grounded to have a zero potential. May be given.

The second member 2 has a form in which the lower surface side is recessed upward except for the peripheral edge, and is provided with a through-hole 21 as a light passing part so as to communicate with the inside of the recessed part 20. I have. The through hole 21 has a rectangular opening surface and is provided directly above the mirror portion 15 of the movable portion 10, and the opening area thereof is equal to or larger than the mirror portion 15 in plan view. . Therefore, when the second member 2 is arranged on the first member 1, the entire mirror portion 15 faces the through hole 21 when viewed from directly above, and light is appropriately transmitted to the mirror portion 15 side through the through hole 21. And introduce
Further, the reflected light from the mirror unit 15 can be appropriately emitted. The light transmitting portion does not necessarily need to be formed as the through hole 21, and may be, for example, the entire second member 2 or the second member 2.
The portion directly above the mirror portion 15 may be formed of a transparent body to allow light to pass (transmit).

The bottom surface 20a of the recess 20 has a pair of third electrode portions 22 facing the first electrode 14 of the movable portion 10.
a, 22b are provided. These third electrode portions 22
a, 22b are not clearly shown in the drawing, but each of the torsion bar portions 12a, 12a along the edge of the through hole 21.
b extends in the same direction as the direction in which the torsion bars 12a and 12b extend. These third electrode portions 22a and 22b are also formed of, for example, gold or aluminum, and are not shown in the drawing.
Are connected to a control device and are configured to individually apply a potential.

The third member 3 has a shape in which the upper surface side is recessed downward except for the peripheral portion, and a pair of fourth electrode portions 31a and 31b are provided on the bottom surface 30a of the recessed portion 30. ing. The fourth electrode portions 31a and 31b face the second electrode portion 16 of the movable portion 10, respectively, and are planarly symmetrical with respect to the axes of the torsion bar portions 12a and 12b in plan view. It is provided separately. These fourth electrode portions 31a and 31b are also formed of, for example, gold or aluminum, and are not shown in the drawing.
It is connected to a control device and configured to individually apply a potential.

In the galvanomirror device X1 in which the members 1, 2, and 3 are configured as described above, the fixing portion 1A is formed by the frame 11, the second member 3, and the third member 3 of the first member 1.
The internal space 1B is the communication space 13 of the first member 1, the second member 2
And the inner space of each of the recessed portions 20 and 30 of the third member 3.

In the galvanomirror device X1 described above,
In the internal space 1B, the torsion bar portions 12a, 12
As described above, the movable portion 10 is rotatable around the axis b of FIG. Such a rotating operation of the movable portion 10 is as follows, assuming that each of the first electrode portion 14 and the second electrode portion 16 of the movable portion 10 is grounded via the wiring portion 19. is there.

For example, if a positive or negative voltage is applied to at least one of the third electrode portion 22a and the fourth electrode portion 31b, and preferably to both, the clockwise direction in FIG. The movable part 10 rotates in (). This is because the first and second electrode portions 14 and 16 are grounded, so that if a voltage is applied to at least one of the third electrode portion 22a and the fourth electrode portion 31b, the first electrode portion 14 and the third This is because electrostatic attraction acts between the electrode portion 22a or between the second electrode portion 16 and the fourth electrode portion 31b.

On the other hand, if a positive or negative voltage is applied to at least one of the third electrode part 22b and the fourth electrode part 31a, and preferably to both, the first electrode part 14 and the third electrode part 22b can be connected. An electrostatic attraction acts between the two or between the second electrode part 16 and the fourth electrode part 31a, and the movable part 10 rotates in the counterclockwise direction in FIG. 2 (the direction of arrow B in the figure).

In the galvanomirror device X1 described above, the first electrode portion 14 is formed over substantially the entire surface 10a of the movable portion 10, and the electrostatic portion is electrostatically applied to the movable portion 10 from each of the upper and lower sides. It is possible to exert an attractive force. For this reason, it is possible to secure a large electrostatic attraction that can be applied to the movable section 10, and it is possible to rotate the movable section 10 with good responsiveness and at a low voltage. If a large electrostatic attractive force acting on the movable unit 10 can be secured, the area of the movable unit 10 in a plan view can be reduced, and the miniaturization of the galvanomirror device X1 itself can be achieved. Also, the movable part 1
0 can be reduced in plan view area, the torsion bar 1
Since the length of the torsion bar portion 1a and 12b can be made large and the cross-sectional area can be reduced.
The torsional rigidity of 2a and 12b is reduced, and low-voltage driving becomes possible.

Next, second to fifth embodiments of the galvanomirror device according to the present invention will be described with reference to FIGS. In these figures, the galvanomirror device X1 of the first embodiment shown in FIGS. 1 and 2 is shown.
The same reference numerals are given to the same members and elements as
These descriptions are omitted below.

The galvanomirror device X2 of the second embodiment shown in FIG. 3 differs from the galvanomirror device X1 of the first embodiment described above in that the mirror portion 15A is formed in a circular shape. . That is, in the present invention,
The shape of the mirror part is a matter of design, and the shape may be rectangular (first embodiment) or circular (second embodiment). Of course, a rhombus, an ellipse, a semicircle, Oval and other shapes can also be employed.

In the galvanomirror device X3 of the third embodiment shown in FIG. 4, the mirror portion 15B has two dielectric layers 15
B ′ and 15B ″ are different from the galvanomirror devices X1 and X2 of the above-described embodiments. Each of the dielectric layers 15B ′ and 15B ″ has a different dielectric constant. And one of the dielectric layers 15B '
Constitutes a region having a high reflectivity for red light, and the other dielectric layer 15B "constitutes a region having a high reflectivity for blue light.

In such a galvanomirror device X3,
For example, in an optical disk device or the like in which the device X3 is incorporated, there are a plurality of types of objects (optical disks, etc.) from which information is read and written, and even if the light irradiated to each of the objects has a different wavelength, each wavelength is different. Light can be efficiently reflected, and information can be read and written satisfactorily for each object.

The galvanomirror device X4 of the fourth embodiment shown in FIG. 5 differs from the galvanomirror devices X1 to X3 of the above-described embodiments in the following three points.
The first difference is that the mirror section 15C is shared with the first electrode section 14. That is, the mirror portion 15C is not provided by laminating a dielectric layer on the first electrode portion 14, but the first electrode portion 14 is formed of a material having a high light reflectance, and a partial region thereof is formed by the mirror portion 15C. Is composed.
If this configuration is adopted, it is not necessary to separately form a dielectric layer on the first electrode unit 14, so that the manufacturing process is simplified,
The manufacturing cost can be reduced.

Second, in that the first electrode portion 14 and the second electrode portion 16 of the movable portion 10 are electrically connected via the conductor layer 18A provided on the side surface of the movable portion 10, thirdly, It differs from the galvanomirror devices X1 to X3 of the above-described embodiments in that a counter balance film is not provided. That is, in the present invention, the means for electrically connecting the first electrode portion 14 and the second electrode portion 16 can be appropriately changed.
Further, the first electrode section 14 and the second electrode section 16 do not necessarily need to be electrically connected to each other, and may be configured to individually apply a potential to each. Furthermore, whether to provide a counter balance film on the other surface 10B of the movable unit 10 is also a design matter.

The galvanomirror device X5 according to the fifth embodiment shown in FIG. 6 has a movable section electrode portion 14 '(corresponding to the first electrode section in each of the above-described embodiments) only on one surface 10a of the movable section 10. ) Is formed, and only the fixed portion electrode portions 22a 'and 22b' corresponding to the third electrode portion in each embodiment are formed in the fixed portion 1A '. This is significantly different from the mirror device X1. Accordingly, the fixing portion 1A 'is connected to the frame portion 11' of the first member 1 'and the second member 2'.
And the third member 3 described above can be omitted.

In this configuration, a potential difference is applied between the movable portion electrode portion 14 'and the fixed portion electrode portions 22a' and 22b 'along the galvanometer mirror devices X1 to X4 of the above-described embodiments. The movable part 10 can be rotated by
Also, while reducing the area of the movable part 10, the movable part electrode part 1
Since a large area 4 'can be secured, a small-sized galvanomirror device X5 that can be driven at a low voltage can be constructed.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a first embodiment of a galvanomirror device according to the present invention.

FIG. 2 is a cross-sectional view of the galvanomirror device of FIG.

FIG. 3 is an exploded perspective view showing a second embodiment of the galvanomirror device according to the present invention.

FIG. 4 is an exploded perspective view showing a third embodiment of the galvanomirror device according to the present invention.

FIG. 5 is a sectional view showing a fourth embodiment of the galvanomirror device according to the present invention.

FIG. 6 is a sectional view showing a fifth embodiment of the galvanomirror device according to the present invention.

FIG. 7 is an exploded perspective view showing an example of a conventional galvanometer mirror device.

8 is a cross-sectional view of the galvanomirror device of FIG.

[Explanation of symbols]

X1 to X5 Galvano mirror device 1A, 1A 'Fixed portion 1B Internal space 1, 1' First member 10 Movable portion 10a One surface (of movable portion) 10b Other surface (of movable portion) 12a, 12b Torsion bar portion 14 First electrode Part 14 'Movable part electrode part (corresponding to first electrode part) 15, 15A to 15C Mirror part 16 Second electrode part 2 Second member 21 Through hole (light passing part) 22a, 22b Third electrode part 22a', 22b 'Fixed part electrode part (corresponding to the third electrode part) 3 Third member 31a, 31b Fourth electrode part

Claims (5)

[Claims] 1. A fixed portion having an internal space and provided with a light passing portion allowing light to pass therethrough, and a rotatable inside of the internal space through a pair of torsion bars with respect to the fixed portion. A supported movable portion, a mirror portion formed on a surface of the movable portion directly below the light passing portion, and a first electrode portion and a second electrode portion provided on one surface and the other surface of the movable portion, respectively. And a third electrode portion and a fourth electrode portion provided in regions of the fixing portion opposed to the first electrode portion and the second electrode portion, respectively, wherein the first electrode portion and the third electrode portion are provided. A galvanomirror device configured to rotate the movable portion by electrostatic force when a potential difference is applied to at least one of the movable portion and the second electrode portion and between the second electrode portion and the fourth electrode portion. One of the above movable parts Characterized in that a part of the area, is shared by the said first electrode portion and the mirror portion in,
Galvano mirror device. 2. The method according to claim 1, wherein the first electrode portion is formed over an entire area or substantially the entire area of one surface of the movable section, and the mirror section is a dielectric layer laminated on the first electrode section. Item 2. A galvanomirror device according to item 1. 3. The galvanomirror device according to claim 2, wherein said dielectric layer has a plurality of regions having different dielectric constants. 4. The first electrode portion and the second electrode portion are electrically connected to each other, and the first electrode portion is connected to the first torsion bar portion via a wiring portion formed on one of the torsion bar portions. 4. The galvanomirror device according to claim 1, wherein a voltage is applied to both the electrode unit and the second electrode unit at the same time. 5. A fixed portion having an internal space and provided with a light passing portion allowing light to pass therethrough, and a rotatable inside of the internal space with respect to the fixed portion via a pair of torsion bar portions. A supported movable portion, a mirror portion formed in a region directly below the light passing portion on one surface of the movable portion, and a movable portion electrode portion provided on one surface of the movable portion,
A fixed portion electrode portion provided in a region opposed to the movable portion electrode portion in the fixed portion, and provided by an electrostatic force when a potential difference is applied between the movable portion electrode portion and the fixed portion electrode portion. A galvanomirror device configured to rotate the movable portion, wherein a part of a surface of the movable portion is shared by the movable portion electrode portion and the mirror portion. A galvanomirror device.