JP5949345B2 - Actuator, optical scanner, image display device, and head mounted display - Google Patents

Description

  The present invention relates to an actuator, an optical scanner, an image display device, and a head mounted display.

For example, an optical scanner that scans light two-dimensionally is known as an actuator (optical device) used in a projector or the like (see, for example, Patent Document 1).
The optical scanner described in Patent Document 1 includes an insulating substrate provided with a pair of permanent magnets, and a scanner main body supported by the insulating substrate so as to be positioned between the pair of permanent magnets. The scanner body includes a frame-shaped support portion, a frame-shaped outer movable plate provided inside the support portion, and an inner movable plate (mirror) provided inside the outer movable plate. . The outer movable plate is connected to the support portion via a pair of first torsion bars extending in the X-axis direction, and the inner movable plate extends in the Y-axis direction orthogonal to the X-axis direction. It is connected to the outer movable plate via a pair of second torsion bars. The outer movable plate and the inner movable plate are each provided with a coil.
In the optical scanner having such a configuration, the outer movable plate and the inner movable plate have the first torsion bar as the central axis due to the interaction between the magnetic field generated from each coil by energization and the magnetic field generated between the pair of permanent magnets. The inner movable plate swings around the Y axis with the second torsion bar as the central axis.

JP-A-8-322227

However, since the optical scanner described in Patent Document 1 is not provided with a yoke or a core between the permanent magnet and the coil, the magnetic field lines of the magnetic field from the permanent magnet cannot be concentrated inside the coil. Therefore, in order to swing the inner movable plate and the outer movable plate at a desired swing angle (swing angle), it is necessary to increase the current to the coil. For this reason, the conventional optical scanner has a problem that power consumption is increased.
An object of the present invention is an actuator that adopts a moving coil system and can scan light two-dimensionally when applied to an optical scanner, an actuator that can save power, an optical scanner, and an image display device And providing a head-mounted display.

Such an object is achieved by the present invention described below.
The actuator of the present invention includes a movable part that can swing around a first axis,
A first shaft portion that supports the movable portion in a swingable manner around the first axis;
A frame body part that supports the first shaft part and is swingable around a second axis that intersects the first axis;
A second shaft portion supporting the frame body portion so as to be swingable around the second axis;
A support portion for supporting the second shaft portion;
A coil provided in the frame part;
A permanent magnet for generating a magnetic field acting on the coil;
A first soft magnetic body and a second soft magnetic body provided in the support portion and forming a magnetic path between the permanent magnet and the coil;
Of the four regions of the support section divided by the first axis and the second axis in a plan view as viewed from a direction perpendicular to the first axis and the second axis, 1 When one region is a first region, and a region that is point-symmetric with respect to the intersection of the first axis and the second axis with respect to the first region is a second region, The first soft magnetic material is located in the first region, and the second soft magnetic material is located in the second region.
According to the actuator configured as described above, power saving can be achieved in an actuator that adopts a moving coil system and can scan light two-dimensionally when applied to an optical scanner.

In the actuator according to the aspect of the invention, the first soft magnetic body may have a portion extending outside the first region across the first axis in the plan view, and with respect to the second axis. Provided on the first region side;
The second soft magnetic body has a portion extending out of the second region across the first axis in the plan view, and on the second region side with respect to the second axis. Is preferably provided.
As a result, the direction component parallel to the first axis of the magnetic field acting on the coil can be increased, and the frame body can be efficiently swung around the second axis.

In the actuator of the present invention, the coil is provided on one surface side of the frame body portion,
It is preferable that the first soft magnetic body and the second soft magnetic body are respectively provided on the same surface side as the coil of the support portion.
As a result, the centers of the first soft magnetic body and the second soft magnetic body and the center of the coil can be matched or brought closer to each other in a direction perpendicular to the first axis and the second axis. Here, wiring and terminals for energizing the coil are usually arranged on the same surface side as the coil of the support part, but the first soft magnetic body and the second soft magnetic body are part of the support part. Since the first soft magnetic body and the second soft magnetic body of the support portion are not provided, the wiring and the terminal can be arranged in the remaining region.

In the actuator according to the aspect of the invention, it is preferable that each of the first soft magnetic body and the second soft magnetic body has a shape in which a width gradually decreases toward the coil side in the plan view.
Thereby, the magnetic field from a permanent magnet can be efficiently concentrated on a coil.
In the actuator of the present invention, it is preferable that the first soft magnetic body and the second soft magnetic body each have a plate shape.
Thereby, cost reduction and size reduction can be achieved. In addition, when the light reflecting plate is fixed to the movable part, the first soft magnetic body and the second soft magnetic body can be installed while securing a space for swinging the light reflecting plate.

In the actuator according to the aspect of the invention, it is preferable that the support portion has a concave portion in which the first soft magnetic body and the second soft magnetic body are provided.
Thereby, even if the thickness of the first soft magnetic body and the second soft magnetic body is larger than the thickness of the coil, the first soft magnetic body is perpendicular to the first axis and the second axis. The center of the body and the second soft magnetic body and the center of the coil can be matched or brought close to each other. In addition, when the light reflecting plate is fixed to the movable part, the first soft magnetic body and the second soft magnetic body can be installed while securing a space for swinging the light reflecting plate.

In the actuator according to the aspect of the invention, it is preferable that the first soft magnetic body and the second soft magnetic body include a reflection reduction unit that reduces a light reflectance on a surface opposite to the support unit.
Thereby, it is possible to prevent unnecessary light incident on the first soft magnetic body or the second soft magnetic body from becoming stray light.
In the actuator of the present invention, the actuator has a light reflecting plate fixed to the movable part and provided with a light reflecting part having light reflectivity,
The frame body portion is provided surrounding the movable portion,
The light reflecting plate is separated from the first shaft portion in the thickness direction of the light reflecting plate, and is provided so as to overlap with at least a part of the first shaft portion when viewed from the plate thickness direction. Preferably it is.
Thereby, size reduction of an actuator can be achieved.

The actuator of the present invention includes a voltage application unit that applies a voltage to the coil,
The voltage application unit includes:
A first voltage generator for generating a first voltage of a first frequency;
A second voltage generator for generating a second voltage of a second frequency different from the first frequency;
A voltage superimposing unit that superimposes the first voltage and the second voltage;
It is preferable that the movable portion is swung around the first axis at the first frequency and is swung around the second axis at the second frequency.
Thereby, size reduction of an actuator can be achieved.

An optical scanner of the present invention includes a movable part that can swing around a first axis;
A light reflecting plate fixed to the movable part and provided with a light reflecting part having light reflectivity;
A first shaft portion that supports the movable portion in a swingable manner around the first axis;
A frame body part that supports the first shaft part and is swingable around a second axis that intersects the first axis;
A second shaft portion supporting the frame body portion so as to be swingable around the second axis;
A support portion for supporting the second shaft portion;
A coil provided in the frame part;
A permanent magnet for generating a magnetic field acting on the coil;
A first soft magnetic body and a second soft magnetic body provided in the support portion and forming a magnetic path between the permanent magnet and the coil;
Of the four regions of the support section divided by the first axis and the second axis in a plan view as viewed from a direction perpendicular to the first axis and the second axis, 1 When one region is a first region, and a region that is point-symmetric with respect to the intersection of the first axis and the second axis with respect to the first region is a second region, The first soft magnetic material is located in the first region, and the second soft magnetic material is located in the second region.
According to the optical scanner configured as described above, power saving can be achieved in the optical scanner that scans light two-dimensionally by the moving coil method.

An image display device of the present invention includes a movable part that can swing around a first axis,
A light reflecting plate fixed to the movable part and provided with a light reflecting part having light reflectivity;
A first shaft portion that supports the movable portion in a swingable manner around the first axis;
A frame body part that supports the first shaft part and is swingable around a second axis that intersects the first axis;
A second shaft portion supporting the frame body portion so as to be swingable around the second axis;
A support portion for supporting the second shaft portion;
A coil provided in the frame part;
A permanent magnet for generating a magnetic field acting on the coil;
A first soft magnetic body and a second soft magnetic body provided in the support portion and forming a magnetic path between the permanent magnet and the coil;
Of the four regions of the support section divided by the first axis and the second axis in a plan view as viewed from a direction perpendicular to the first axis and the second axis, 1 When one region is a first region, and a region that is point-symmetric with respect to the intersection of the first axis and the second axis with respect to the first region is a second region, The first soft magnetic material is located in the first region, and the second soft magnetic material is located in the second region.
According to the image display device configured as described above, it is possible to achieve power saving of the optical scanner that scans light two-dimensionally by the moving coil method.

The head-mounted display of the present invention includes a movable part that can swing around a first axis;
A light reflecting plate fixed to the movable part and provided with a light reflecting part having light reflectivity;
A first shaft portion that supports the movable portion in a swingable manner around the first axis;
A frame body part that supports the first shaft part and is swingable around a second axis that intersects the first axis;
A second shaft portion supporting the frame body portion so as to be swingable around the second axis;
A support portion for supporting the second shaft portion;
A coil provided in the frame part;
A permanent magnet for generating a magnetic field acting on the coil;
A first soft magnetic body and a second soft magnetic body provided in the support portion and forming a magnetic path between the permanent magnet and the coil;
Of the four regions of the support section divided by the first axis and the second axis in a plan view as viewed from a direction perpendicular to the first axis and the second axis, 1 When one region is a first region, and a region that is point-symmetric with respect to the intersection of the first axis and the second axis with respect to the first region is a second region, The first soft magnetic material is located in the first region, and the second soft magnetic material is located in the second region.
According to the head mounted display configured as described above, it is possible to achieve power saving of the optical scanner that scans light two-dimensionally by the moving coil method.

It is a top view which shows 1st Embodiment of the actuator (optical scanner) of this invention. FIG. 2 is a cross-sectional view (cross-sectional view along the X axis) of the actuator shown in FIG. 1. It is a block diagram for demonstrating the voltage application part of the drive part with which the actuator shown in FIG. 1 is provided. It is a figure which shows an example of the voltage generated in the 1st voltage generation part shown in FIG. 3, and a 2nd voltage generation part. It is a figure for demonstrating the 1st soft magnetic body with which the actuator shown in FIG. 1 is equipped, and a 2nd soft magnetic body. It is sectional drawing which shows 2nd Embodiment of the actuator (optical scanner) of this invention. It is a figure for demonstrating the 1st soft magnetic body with which the actuator shown in FIG. 6 is equipped, and a 2nd soft magnetic body. It is a figure which shows typically embodiment of the image display apparatus of this invention. It is a perspective view which shows the application example 1 of the image display apparatus of this invention. It is a perspective view which shows the application example 2 of the image display apparatus of this invention. It is a perspective view which shows the application example 3 of the image display apparatus of this invention.

Hereinafter, preferred embodiments of an actuator, an optical scanner, and an image display device of the present invention will be described with reference to the accompanying drawings. In the following embodiments, a case where the actuator of the present invention is applied to an optical scanner (optical device) will be representatively described.
<First Embodiment>
FIG. 1 is a plan view showing a first embodiment of an actuator (optical scanner) of the present invention, and FIG. 2 is a cross-sectional view (cross-sectional view along the X axis) of the actuator shown in FIG. 3 is a block diagram for explaining a voltage application unit of the drive unit provided in the actuator shown in FIG. 1, and FIG. 4 is a voltage generated by the first voltage generation unit and the second voltage generation unit shown in FIG. It is a figure which shows an example. FIG. 5 is a view for explaining the first soft magnetic body and the second soft magnetic body included in the actuator shown in FIG. In the following, for convenience of explanation, the upper side in FIG. 2 is referred to as “upper” and the lower side is referred to as “lower”. For the sake of explanation, FIG. 1 shows a plan view of a state where the movable mirror portion is seen through.

  As shown in FIGS. 1 and 2, the optical scanner 1 includes a movable mirror unit 11, a pair of shaft portions 12a and 12b (first shaft portion), a frame body portion 13, and two pairs of shaft portions 14a. 14b, 14c, 14d (second shaft portion), support portion 15, permanent magnet 21, soft magnetic body (first soft magnetic body) 22, soft magnetic body (second soft magnetic body) 23, The coil 31 and the voltage application part 4 (not shown) are provided.

Here, the movable mirror portion 11 and the pair of shaft portions 12a and 12b constitute a first vibration system that swings (reciprocates) around the Y axis (first axis). In addition, the movable mirror unit 11, the pair of shaft portions 12a and 12b, the frame body portion 13, the two pairs of shaft portions 14a, 14b, 14c, and 14d, and the coil 31 are orthogonal to (intersect) the Y axis. A second vibration system that swings (reciprocally rotates) around the second axis).
Further, the permanent magnet 21, the soft magnetic bodies 22, 23, the coil 31, and the voltage application unit 4 (not shown) drive the first vibration system and the second vibration system described above (that is, the movable mirror unit 11 is moved). A drive unit that swings around the X axis and the Y axis is configured.

Hereinafter, each part of the optical scanner 1 will be described in detail sequentially.
The movable mirror part 11 includes a base part (movable part) 111 and a light reflection plate 113 fixed to the base part 111 via a spacer 112.
A light reflecting portion 114 having light reflectivity is provided on the upper surface (one surface) of the light reflecting plate 113.
The light reflecting plate 113 is separated from the shaft portions 12a and 12b in the thickness direction of the light reflecting plate 113, and from the thickness direction of the light reflecting plate 113 (direction perpendicular to both the X axis and the Y axis). When viewed (hereinafter also referred to as “plan view”), it is provided so as to overlap the shaft portions 12 a and 12 b.

Therefore, the area of the plate surface of the light reflecting plate 113 can be increased while shortening the distance between the shaft portion 12a and the shaft portion 12b. Further, since the distance between the shaft portion 12a and the shaft portion 12b can be shortened, the size of the frame body portion 13 can be reduced. Furthermore, since the size of the frame body portion 13 can be reduced, the distance between the shaft portions 14a and 14b and the shaft portions 14c and 14d can be shortened. Further, since the distance between the shaft portions 14a and 14b and the shaft portions 14c and 14d can be shortened, the support portion 15 can be reduced in size. Further, since the support portion 15 can be reduced in size, when a pair of magnetic poles of the permanent magnet 21 described later is disposed outside the support portion 15, the distance between the pair of magnetic poles can be shortened. it can.
For this reason, even if the area of the plate surface of the light reflecting plate 113 is increased, the optical scanner 1 can be downsized.

Further, when the pair of magnetic poles of the permanent magnet 21 is arranged outside the support portion 15, the distance between the pair of magnetic poles can be shortened, so that the magnetic field of the permanent magnet 21 can be efficiently transferred to the coil 31. Can act. Therefore, the swing angle of the light reflecting plate 113 can be increased while reducing the size of the permanent magnet 21.
Further, the light reflection plate 113 is formed so as to cover the entire shaft portions 12a and 12b in plan view. In other words, each of the shaft portions 12a and 12b is located inside the outer periphery of the light reflecting plate 113 in plan view. Thereby, the area of the plate | board surface of the light reflection board 113 becomes large, As a result, the area of the light reflection part 114 can be enlarged. Further, unnecessary light (for example, light that could not enter the light reflecting portion 114) can be prevented from being reflected by the shaft portions 12a and 12b and becoming stray light.

  The light reflecting plate 113 is formed so as to cover the entire frame body portion 13 in plan view. In other words, the frame body portion 13 is located on the inner side with respect to the outer periphery of the light reflecting plate 113 in plan view. Thereby, the area of the plate | board surface of the light reflection board 113 becomes large, As a result, the area of the light reflection part 114 can be enlarged. Further, it is possible to prevent unnecessary light from being reflected by the frame body portion 13 and becoming stray light.

  Furthermore, the light reflecting plate 113 is formed so as to cover the entire shaft portions 14a, 14b, 14c, and 14d in plan view. In other words, each of the shaft portions 14a, 14b, 14c, and 14d is located inside the outer periphery of the light reflecting plate 113 in plan view. Thereby, the area of the plate | board surface of the light reflection board 113 becomes large, As a result, the area of the light reflection part 114 can be enlarged. Further, it is possible to prevent unnecessary light from being reflected by the shaft portions 14a, 14b, 14c, and 14d and becoming stray light.

In the present embodiment, the light reflecting plate 113 has a circular shape in plan view. In addition, the planar view shape of the light reflecting plate 113 is not limited to this, and may be, for example, an elliptical shape, a polygonal shape such as a square shape, or a shape having an outer shape along the outer shape of the entire vibration system. Also good. By making the light reflecting plate 113 project in the direction along the X axis and the Y axis, an increase in the moment of inertia of the light reflecting plate 113 can be suppressed.
A hard layer 115 is provided on the lower surface of the light reflecting plate 113 (the other surface, the surface on the base 111 side of the light reflecting plate 113).

  The hard layer 115 is made of a material harder than the constituent material of the light reflecting plate 113 main body. Thereby, the rigidity of the light reflecting plate 113 can be increased. Therefore, it is possible to prevent or suppress the bending when the light reflecting plate 113 swings. Further, the thickness of the light reflecting plate 113 can be reduced, and the moment of inertia when the light reflecting plate 113 swings around the X axis and the Y axis can be suppressed.

The constituent material of such a hard layer 115 is not particularly limited as long as it is a material harder than the constituent material of the light reflecting plate 113 main body. For example, diamond, crystal, sapphire, lithium tantalate, potassium niobate, A carbon nitride film or the like can be used, but it is particularly preferable to use diamond.
The thickness (average) of the hard layer 115 is not particularly limited, but is preferably about 1 to 10 μm, and more preferably about 1 to 5 μm.

Moreover, the hard layer 115 may be comprised by the single layer, and may be comprised by the laminated body of several layers. The hard layer 115 may be provided on the entire lower surface of the light reflecting plate 113 or may be provided on a part of the lower surface. The hard layer 115 is provided as necessary, and can be omitted.
The hard layer 115 can be formed by, for example, chemical vapor deposition (CVD) such as plasma CVD, thermal CVD, or laser CVD, dry plating such as vacuum deposition, sputtering, or ion plating, electrolytic plating, or immersion plating. Further, wet plating methods such as electroless plating, thermal spraying, and joining of sheet-like members can be used.

In addition, the lower surface of the light reflecting plate 113 is fixed to the base 111 via a spacer 112. Thereby, the light reflecting plate 113 can be swung around the Y axis while preventing contact with the shaft portions 12a, 12b, the frame body portion 13 and the shaft portions 14a, 14b, 14c, 14d.
In addition, the base 111 is located on the inner side with respect to the outer periphery of the light reflecting plate 113 in plan view. The area of the base 111 in plan view is preferably as small as possible if the base 111 can support the light reflecting plate 113 via the spacer 112. Thereby, the distance between the shaft part 12a and the shaft part 12b can be reduced while increasing the area of the plate surface of the light reflecting plate 113.

The frame body portion 13 has a frame shape and is provided so as to surround the base portion 111 of the movable mirror portion 11 described above. In other words, the base 111 of the movable mirror portion 11 is provided inside the frame body portion 13 having a frame shape.
And the frame part 13 is supported by the support part 15 via axial part 14a, 14b, 14c, 14d. Further, the base 111 of the movable mirror part 11 is supported by the frame body part 13 via the shaft parts 12a and 12b.

  Further, the frame body portion 13 has a length in the direction along the Y-axis that is longer than a length in the direction along the X-axis. That is, when the length of the frame body portion 13 in the direction along the Y axis is a and the length of the frame body portion 13 in the direction along the X axis is b, the relationship a> b is satisfied. Thereby, it is possible to suppress the length of the optical scanner 1 in the direction along the X axis while securing the length necessary for the shaft portions 12a and 12b.

Moreover, the frame part 13 has comprised the shape along the external shape of the structure which consists of the base 111 of the movable mirror part 11, and one pair of axial parts 12a and 12b by planar view. Accordingly, the frame body portion 13 is allowed while allowing the vibration of the first vibration system configured by the movable mirror portion 11 and the pair of shaft portions 12a and 12b, that is, swinging of the movable mirror portion 11 around the Y axis. Can be miniaturized.
In addition, if the shape of the frame part 13 is a frame shape, it will not be limited to the thing of illustration.

The shaft portions 12a, 12b and the shaft portions 14a, 14b, 14c, 14d can be elastically deformed, respectively.
The shaft portions 12a and 12b connect the movable mirror portion 11 and the frame body portion 13 so that the movable mirror portion 11 can swing (rotate) around the Y axis (first axis). . Further, the shaft portions 14a, 14b, 14c, and 14d are arranged so that the frame body portion 13 can swing (turn) around the X axis (second axis) orthogonal to the Y axis. The support part 15 is connected.

  The shaft portions 12 a and 12 b are disposed so as to face each other via the base 111 of the movable mirror portion 11. Each of the shaft portions 12a and 12b has a longitudinal shape extending in the direction along the Y axis. Each of the shaft portions 12 a and 12 b has one end connected to the base 111 and the other end connected to the frame body 13. In addition, the shaft portions 12a and 12b are arranged so that the central axis thereof coincides with the Y axis.

Thus, the shaft portions 12a and 12b that support the base portion 111 so as to be swingable around the Y axis are torsionally deformed as the movable mirror portion 11 swings around the Y axis.
The shaft portions 14 a and 14 b and the shaft portions 14 c and 14 d are disposed so as to face each other with the frame body portion 13 interposed therebetween. The shaft portions 14a, 14b, 14c, and 14d each have a longitudinal shape that extends in a direction along the X axis. Each of the shaft portions 14 a, 14 b, 14 c, and 14 d has one end connected to the frame body portion 13 and the other end connected to the support portion 15. Further, the shaft portions 14a and 14b are disposed so as to face each other via the X axis, and similarly, the shaft portions 14c and 14d are disposed so as to face each other via the X axis.

As described above, the shaft portions 14a, 14b, 14c, and 14d that support the frame body portion 13 so as to be swingable around the X axis correspond to the entire shaft portions 14a and 14b as the frame body portion 13 swings around the X axis. The entire shaft portions 14c and 14d are torsionally deformed.
As described above, the movable mirror unit 11 (light reflecting plate 113) is orthogonal to each other by making the movable mirror unit 11 swingable about the Y axis and the frame body unit 13 swinging about the X axis. It can be swung (rotated) about two axes, the X axis and the Y axis.
The shapes of the shaft portions 12a, 12b and the shaft portions 14a, 14b, 14c, 14d are not limited to those described above. You may do it.

The support portion 15 that supports the shaft portions 14a, 14b, 14c, and 14d has a frame shape formed so as to surround the frame body portion 13 in plan view.
The base portion 111, the shaft portions 12a and 12b, the frame body portion 13, the shaft portions 14a, 14b, 14c and 14d, and the support portion 15 as described above are integrally formed.
In the present embodiment, the base 111, the shaft portions 12a and 12b, the frame body portion 13, the shaft portions 14a, 14b, 14c and 14d, and the support portion 15 are composed of the first Si layer (device layer) and the SiO ₂ layer (box Layer) and a second Si layer (handle layer) are formed by etching the SOI substrate. Thereby, the vibration characteristics of the first vibration system and the second vibration system can be made excellent. Further, since the SOI substrate can be finely processed by etching, the base portion 111, the shaft portions 12a and 12b, the frame body portion 13, the shaft portions 14a, 14b, 14c, and 14d and the support portion 15 are formed using the SOI substrate. By forming, the dimensional accuracy can be made excellent, and the optical scanner 1 can be downsized.

  The base 111, the shafts 12a and 12b, and the shafts 14a, 14b, 14c, and 14d are each configured by a first Si layer of an SOI substrate. Thereby, the elasticity of shaft part 12a, 12b and shaft part 14a, 14b, 14c, 14d can be made excellent. Further, it is possible to prevent the base 111 from coming into contact with the frame body portion 13 when rotating around the Y axis.

Further, the frame body portion 13 and the support portion 15, respectively, a first Si layer of the SOI substrate, and a stack of the SiO ₂ layer and the second Si layer. Thereby, the rigidity of the frame part 13 and the support part 15 can be made excellent.
Moreover, it is preferable that the antireflection process is performed to the part located in the outer side of the light reflection board 113 among the upper surfaces of the support part 15 by planar view. Thereby, it is possible to prevent unnecessary light irradiated to other than the light reflection plate 113 from becoming stray light. In addition, when the light reflecting plate 113 is downsized, it is located outside the light reflecting plate 113 among the upper surfaces of the shaft portions 12a and 12b, the shaft portions 14a, 14b, 14c, and 14d, and the frame body portion 13 in plan view. It is preferable that an antireflection treatment is also applied to the portion to be processed.

Such an antireflection treatment is not particularly limited, and examples thereof include formation of an antireflection film (dielectric multilayer film), roughening treatment, and black treatment.
Note that the above-described constituent materials and forming methods of the base portion 111, the shaft portions 12a and 12b, and the shaft portions 14a, 14b, 14c, and 14d are merely examples, and the present invention is not limited thereto.

In this embodiment, the spacer 112 and the light reflecting plate 113 are also formed by etching the SOI substrate. The spacer 112 is composed of a laminate composed of the SiO ₂ layer and the second Si layer of the SOI substrate. The light reflecting plate 113 is composed of a first Si layer of an SOI substrate.
Thus, by forming the spacer 112 and the light reflecting plate 113 using the SOI substrate, the spacer 112 and the light reflecting plate 113 joined to each other can be manufactured easily and with high accuracy.

Such a spacer 112 is bonded to the base 111 by a bonding material (not shown) such as an adhesive or a brazing material.
The coil 31 is joined to the upper surface (the surface on the light reflecting plate 113 side) of the frame body portion 13 that supports the shaft portions 14a, 14b, 14c, and 14d.
The coil 31 has an annular shape formed along the circumferential direction of the frame body portion 13. Therefore, the coil 31 generates a magnetic field in a direction orthogonal to both the X axis and the Y axis in the vicinity of the inside of the frame body portion 13 when a voltage is applied.

Although it does not specifically limit as a joining method of the coil 31 and the frame part 13, For example, the joining method using an adhesive agent can be used.
Note that the coil 31 may be obtained by previously joining a coil in the form of a coil to the frame body portion 13 or by patterning the frame body portion 13 into a coil shape using a known film forming method. It may be formed.

Such a coil 31 is electrically connected to the voltage application unit 4. The voltage application unit 4 will be described in detail later.
Moreover, the magnetic field from the permanent magnet 21 acts on such a coil 31. Here, between the permanent magnet 21 and the coil 31, soft magnetic bodies 22 and 23 that form a magnetic path between the permanent magnet 21 and the coil 31 are provided. Therefore, the magnetic field from the permanent magnet 21 acts on the coil 31 via the soft magnetic bodies 22 and 23. Further, the permanent magnet 21 in the present embodiment is arranged so as to generate a magnetic field that sequentially passes through the second soft magnetic body 23, the coil 31, and the first soft magnetic body 22.

The permanent magnet 21 may be composed of a pair of permanent magnets including a permanent magnet having a magnetic pole 21a and a permanent magnet having a magnetic pole 21b, or a single permanent magnet having magnetic poles 21a and 21b. May be. In addition, the magnetic pole 21 a may be in contact with the soft magnetic body 22, and similarly, the magnetic pole 21 b may be in contact with the soft magnetic body 23. Further, another soft magnetic body (core, yoke) may be provided between the magnetic pole 21a and the soft magnetic body 22 and between the magnetic pole 21b and the soft magnetic body 23, respectively. In the illustrated example, the line segment connecting the magnetic pole 21a and the magnetic pole 21b of the permanent magnet 21 is inclined with respect to the X axis and the Y axis in plan view, but the magnetic field from the permanent magnet 21 is soft magnetic. If the magnetic field which will be described later can be generated between the soft magnetic bodies 22 and 23 by being guided to the bodies 22 and 23, the shape, arrangement and the like of the permanent magnet 21 are not particularly limited. For example, you may have two pairs of magnets provided so that the 1st soft magnetic body 22 and the 2nd soft magnetic body 23 might be pinched | interposed from the upper surface and lower surface of the support part 15, respectively.
As such a permanent magnet 21, for example, a neodymium magnet, a ferrite magnet, a samarium cobalt magnet, an alnico magnet, a bond magnet, or the like can be suitably used.

The soft magnetic bodies 22 and 23 are provided on the upper surface of the support portion 15.
Here, as shown in FIG. 5, one area S1 (first area) among the four areas S1, S2, S3, and S4 of the support portion 15 divided by the X axis and the Y axis in plan view. ) Is unevenly distributed (positioned) in the soft magnetic body 22 (first soft magnetic body) and faces the region S1 via the intersection point P between the X axis and the Y axis (that is, point symmetry with respect to the intersection point P). The soft magnetic material 23 (second soft magnetic material) is unevenly distributed (positioned) in the region S2 (second region). In FIG. 5, for convenience of explanation, the formation area of the soft magnetic bodies 22 and 23 is shaded. The region S3 faces (adjacent) the region S1 via the X axis and faces (adjacent) the region S2 via the Y axis. The region S4 is opposed (adjacent) to the region S2 via the X axis and is opposed (adjacent) to the region S1 via the Y axis.

That is, in plan view, the soft magnetic body 22 is unevenly distributed on one side (right side in FIG. 5) with respect to the X axis, and the soft magnetic body 23 is located on the other side (left side in FIG. 5) with respect to the X axis. It is unevenly distributed. In plan view, the soft magnetic body 22 is unevenly distributed on one side (upper side in FIG. 5) with respect to the Y axis, and the soft magnetic body 23 is on the other side (lower side in FIG. 5) with respect to the Y axis. Is unevenly distributed.
Here, “the soft magnetic body 22 is unevenly distributed in the region S1 in plan view” means that the main formation region of the soft magnetic body 22 in the plan view is the region S1, more specifically, It means that the area located in the region S1 of the soft magnetic body 22 in plan view is larger than the area located in the regions S2, S3, S4 of the soft magnetic body 22. Similarly, “the soft magnetic material 23 is unevenly distributed in the region S2 in plan view” means that the main formation region of the soft magnetic material 23 in the plan view is the region S2, more specifically in plan view. This means that the area of the soft magnetic body 23 located in the region S2 is larger than the areas of the soft magnetic body 23 located in the regions S1, S3, and S4.

  The soft magnetic body 23 forms a magnetic path from one magnetic pole 21 b of the permanent magnet 21 to the coil 31. The soft magnetic body 22 forms a magnetic path from the coil 31 to the other magnetic pole 21 a of the permanent magnet 21. That is, a magnetic path is formed from one magnetic pole 21 b of the permanent magnet 21 to the other magnetic pole 21 a of the permanent magnet 21 through the soft magnetic body 23, the coil 31, and the soft magnetic body 22 in order.

A magnetic field is generated between the soft magnetic body 22 and the soft magnetic body 23 in a direction inclined with respect to the X axis and the Y axis in plan view. That is, the magnetic field generated between the soft magnetic body 22 and the soft magnetic body 23 by the permanent magnet 21 has a direction component parallel to the X axis and a direction component parallel to the Y axis.
Accordingly, the frame body portion 13 can be swung or vibrated around the X axis and the Y axis by the interaction between the magnetic field and the magnetic field of the coil 31 provided in the frame body portion 13.

Moreover, the soft magnetic bodies 22 and 23 can concentrate the magnetic field lines of the magnetic field from the permanent magnet 21 inside the coil 31. Therefore, power saving of the optical scanner 1 can be achieved.
The soft magnetic body 22 has a portion extending outside the region S1 (that is, in the region S4) across the Y axis in plan view, and provided on the region S1 side (that is, in the region S1) with respect to the X axis. It has been. Similarly, the soft magnetic body 23 has a portion extending outside the region S2 (ie, in the region S3) across the Y axis in plan view, and on the region S2 side (ie, in the region S2) with respect to the X axis. Is provided.

  Thus, since the soft magnetic bodies 22 and 23 each have a portion straddling the Y axis, a region where the soft magnetic body 22 and the soft magnetic body 23 overlap in the Y axis direction can be formed. In addition, by preventing the soft magnetic bodies 22 and 23 from straddling the X axis, the soft magnetic body 22 and the soft magnetic body 23 can be prevented from overlapping in the X axis direction. For this reason, the direction component parallel to the Y axis of the magnetic field acting on the coil 31 can be increased, and the frame body portion 13 can be efficiently swung around the X axis.

  In the present embodiment, the soft magnetic body 22 has an edge portion 221 along the X axis and an edge portion 222 along the Y axis, and the edge portion 221 coincides with the X axis in plan view. 222 is located on the region S4 side with respect to the Y-axis. Similarly, the soft magnetic body 23 has an edge portion 231 along the X axis and an edge portion 232 along the Y axis, the edge portion 231 coincides with the X axis in plan view, and the edge portion 232 is It is located on the region S3 side with respect to the Y axis.

  When the edge portions 221 and 231 are positioned on the X axis in plan view, the direction component parallel to the X axis is most reduced in the magnetic field acting on the coil 31 without decreasing the direction component parallel to the Y axis. Can be bigger. If the edge portions 221 and 231 pass through the edge portions 221 and 231 and a line segment parallel to the X axis passes through the inside of the coil 31, the magnetic field acting on the coil 31 is X It has a directional component parallel to the axis.

  Further, in a plan view, the line segment L1 passes through the edge 222 (particularly the end of the edge 222 on the coil 31 side) and is parallel to the Y axis, and the edge 232 (particularly the coil 31 of the edge 232). Line segment L2 that passes through the coil 31 and passes through the inside of the coil 31. Thereby, the direction component parallel to the Y axis of the magnetic field acting on the coil 31 can be efficiently increased.

From this point of view, when the distance between the line segments L1 and L2 and the Y axis is equal to ½ of the maximum width inside the coil 31 in the X axis direction, the magnetic field acting on the coil 31 is parallel to the Y axis. It can be said that the directional component can be increased most efficiently.
Each of the soft magnetic bodies 22 and 23 has a width (a distance between the edge portion 221 and the edge portion 222 and a space between the edge portion 231 and the edge portion 232 toward the coil 31 side in plan view. ) Has a shape that gradually decreases. Thereby, the magnetic field from the permanent magnet 21 can be efficiently concentrated on the coil 31.

The coil 31 described above is provided on one surface side (upper side) of the frame body portion 13, but the soft magnetic bodies 22 and 23 are respectively on the same surface side (upper side) as the coil 31 of the support portion 15. Is provided.
Thereby, the centers of the soft magnetic bodies 22 and 23 and the center of the coil 31 can be matched or brought close to each other in a direction perpendicular to the X axis and the Y axis.

  Here, although not shown, wiring and terminals for energizing the coil 31 are disposed on the same surface side as the coil 31 of the support portion 15. In the optical scanner 1, since the soft magnetic bodies 22 and 23 are provided in a part of the support portion 15 (mainly the regions S1 and S2), the soft magnetic bodies 22 and 23 of the support portion 15 are not provided. Such wiring and terminals can be arranged in the remaining regions (regions S3 and S4). Although not shown, the optical scanner 1 is provided with a piezoresistive element for detecting the behavior of the movable mirror unit 11 (for example, a swing angle around the Y axis, a frequency, etc.) on the shaft 12a or 12b. A piezoresistive element for detecting the behavior of the frame body portion 13 (for example, the swing angle around the X axis, the frequency, etc.) is provided in any of the portions 14a, 14b, 14c, and 14d. The wiring of these piezoresistive elements is also provided on the same surface side as the coil 31 of the support portion 15.

That is, the soft magnetic bodies 22 and 23 are patterned so as to be electrically insulated from the coil 31 and the wiring and terminals of the piezoresistive element.
In addition, when the insulation process is performed on the surface of the soft magnetic bodies 22 and 23, the wiring and terminals of the coil 31 and the piezoresistive element may be provided on the soft magnetic bodies 22 and 23.
In this embodiment, since the soft magnetic bodies 22 and 23 do not exist in the vicinity of the end portions of the shaft portions 14b and 14c on the support portion 15 side, each wiring as described above is routed through the shaft portions 14b and 14c. It can be connected to a terminal provided on the support portion 15.

The soft magnetic bodies 22 and 23 are each plate-shaped. It should be noted that even in the case of a thin sheet shape, it is a plate-shaped range. Thereby, cost reduction and size reduction can be achieved. Further, the soft magnetic bodies 22 and 23 can be installed while securing a space for the light reflecting plate 113 to swing.
The soft magnetic bodies 22 and 23 having such a plate shape or sheet shape may be formed by forming a film on the support portion 15 using a known film forming method. Since the thicknesses 22 and 23 can be easily and inexpensively increased, it is preferable that a plate-like or sheet-like soft magnetic material is punched and fixed on the support portion 15 with an adhesive or the like. .

Further, the thickness t2 of the soft magnetic bodies 22 and 23 is not particularly limited, but is preferably 1 to 4 times the thickness t1 of the coil 31, specifically, 5 to 200 μm. The following is preferable.
In the drawing, the thicknesses of the soft magnetic bodies 22 and 23 are constant throughout the area, but may have portions having different thicknesses. For example, the magnetic field from the permanent magnet 21 can be more efficiently guided to the coil 31 by increasing the thickness of the permanent magnet 21 on the side of the magnetic poles 21a and 21b.

  The soft magnetic bodies 22 and 23 are each composed of a soft magnetic material as a main material. Such a soft magnetic material is not particularly limited, and examples thereof include Fe, various Fe alloys (silicon iron, permalloy, amorphous, Sendust) and the like. The soft magnetic bodies 22 and 23 may include materials other than the soft magnetic material as long as they have the characteristics of a soft magnetic body as a whole.

Further, it is preferable that a reflection reducing portion for reducing the reflectance of light is provided on the surface (upper surface) opposite to the support portion 15 of the soft magnetic body 22. Similarly, it is preferable that a reflection reduction portion for reducing the reflectance of light is provided on the surface of the soft magnetic body 23 opposite to the support portion 15.
Thereby, it is possible to prevent unnecessary light incident on the soft magnetic bodies 22 and 23 from becoming stray light.
Such a reflection reducing portion can be formed by the same processing as the antireflection processing of the support portion 15 described above.

Here, the voltage application unit 4 electrically connected to the coil 31 will be described.
As shown in FIG. 3, the voltage applying unit 4 includes a first voltage generating unit 41 that generates a _first voltage V ₁ for rotating the movable mirror unit 11 around the Y axis, and a movable mirror unit 11 that is connected to X. A second voltage generator 42 for generating a _second voltage V ₂ for rotating around the axis, and a voltage superimposing unit 43 for superimposing the first voltage V ₁ and the second voltage V ₂ , The voltage superimposed by the voltage superimposing unit 43 is applied to the coil 31.

As shown in FIG. 4A, the first voltage generator 41 generates a first voltage V ₁ (horizontal scanning voltage) that periodically changes in a cycle T ₁ . That is, the first voltage generator 41 generates the first voltage V ₁ having the first frequency (1 / T ₁ ).
First voltages V ₁ is a waveform like a sine wave. Therefore, the optical scanner 1 can perform main scanning of light effectively. Incidentally, the first wave of the voltage V _1, but is not limited thereto.
The first frequency (1 / T ₁ ) is not particularly limited as long as it is a frequency suitable for horizontal scanning, but is preferably 10 to 40 kHz.

  In the present embodiment, the first frequency is set to be equal to the torsional resonance frequency (f1) of the first vibration system (torsional vibration system) composed of the movable mirror portion 11 and the pair of shaft portions 12a and 12b. Has been. That is, the first vibration system is designed (manufactured) so that its torsional resonance frequency f1 is a frequency suitable for horizontal scanning. Thereby, the rotation angle of the movable mirror portion 11 around the Y axis can be increased.

On the other hand, as shown in FIG. 4B, the second voltage generator 42 generates a second voltage V ₂ (vertical scanning voltage) that periodically changes at a period T ₂ different from the period T _1. It is. In other words, the second voltage generator 42 generates the second voltage V ₂ having the second frequency (1 / T ₂ ).
Second voltage V ₂ has a waveform like a sawtooth wave. Therefore, the optical scanner 1 can effectively perform vertical scanning (sub-scanning) of light. Incidentally, the second waveform of the voltage V _2, but is not limited thereto.

The second frequency (1 / T ₂ ) is different from the first frequency (1 / T ₁ ) and is not particularly limited as long as the frequency is suitable for vertical scanning, but is 30 to 120 Hz (about 60 Hz). Is preferred. Thus, the second frequency of the voltage V ₂ is set to about 60 Hz, the frequency of the first voltage V ₁ as described above by a 10 to 40 kHz, at a frequency suitable for rendering on the display, movable mirrors The part 11 can be rotated around each of two axes (X axis and Y axis) orthogonal to each other. However, if it is possible to rotate the movable mirror 11 about their respective axes of X-axis and Y-axis, the first and the frequency of the voltages V ₁ combined with the frequency of the second voltage V ₂ it is not particularly limited .

In the present embodiment, the frequency of the second voltage V ₂ is determined by the movable mirror portion 11, the pair of shaft portions 12 a and 12 b, the frame body portion 13, the two pairs of shaft portions 14 a, 14 b, 14 c and 14 d and the coil 31. The frequency is adjusted to be different from the torsional resonance frequency (resonance frequency) of the configured second vibration system (torsional vibration system).
The second voltage V ₂ of the frequency (second frequency) is preferably smaller than the first voltage V ₁ of the frequency (first frequency). That is, the period _{T 2} are, is preferably longer than the period _{T 1.} Thereby, the movable mirror part 11 can be rotated around the X axis at the second frequency while rotating the movable mirror unit 11 around the Y axis at a second frequency more reliably and smoothly.

Further, when the torsional resonance frequency of the first vibration system is f1 [Hz] and the torsional resonance frequency of the second vibration system is f2 [Hz], f1 and f2 satisfy the relationship of f2 <f1. Is preferable, and it is more preferable to satisfy the relationship of f1 ≧ 10f2. Thereby, the movable mirror unit 11 can be rotated more smoothly around the X axis at the frequency of the second voltage V ₂ while being rotated at the frequency of the first voltage V _1. . On the other hand, when f1 ≦ f2, the vibration of the first vibration system may occur due to the second frequency.

Each of the first voltage generation unit 41 and the second voltage generation unit 42 is connected to the control unit 7 and driven based on a signal from the control unit 7. A voltage superimposing unit 43 is connected to the first voltage generating unit 41 and the second voltage generating unit 42.
The voltage superimposing unit 43 includes an adder 43 a for applying a voltage to the coil 31. The adder 43 a receives the first voltage V ₁ from the first voltage generator 41 and receives the second voltage V ₂ from the second voltage generator 42, and superimposes these voltages and applies them to the coil 31. It has become.

Next, a method for driving the optical scanner 1 will be described. In the present embodiment, as described above, the frequency of the first voltage V ₁ is set equal to the torsional resonance frequency of the first vibration system, and the frequency of the second voltage V ₂ is the second frequency. Is set to a value different from the torsional resonance frequency of the vibration system of FIG. 1 and smaller than the frequency of the first voltage V ₁ (for example, the frequency of the first voltage V ₁ is 18 kHz, the second voltage frequency of V ₂ is set to 60Hz).
For example, the first voltage V ₁ as shown in FIG. 4A and the second voltage V ₂ as shown in FIG. 4B are superimposed by the voltage superimposing unit 43, and the superimposed voltage is coiled. 31 is applied.

Then, the first voltage V ₁ tries to attract one surface side (upper side) of the coil 31 to one magnetic pole 21 a side (S pole side) of the permanent magnet 21 and the other surface side of the coil 31 ( A magnetic field (this magnetic field is referred to as “magnetic field A1”) to be attracted to the other magnetic pole 21 b side (N pole side) of the permanent magnet 21, and one surface side (upper side) of the coil 31 is the permanent magnet 21. Magnetic field to be attracted to the other magnetic pole 21b side (N pole side) and the other surface side (lower side) of the coil 31 to be attracted to one magnetic pole 21a side (S pole side) of the permanent magnet 21. (This magnetic field is referred to as “magnetic field A2”).

Here, as described above, the magnetic field generated between the soft magnetic body 22 and the soft magnetic body 23 by the permanent magnet 21 is inclined with respect to the X axis and the Y axis in plan view. Therefore, the magnetic field generated between the soft magnetic body 22 and the soft magnetic body 23 by the permanent magnet 21 has a component parallel to the X axis. Therefore, by alternately switching between the magnetic field A1 and the magnetic field A2, vibration that the frame body portion 13 rotates around the Y axis is excited, and the shaft portions 12a and 12b are twisted and deformed along with the vibration, movable mirror 11 is rotated around the Y-axis at a first frequency of the voltage V _1.
Also, the frequency of the first voltage V ₁ is equal to the torsional resonance frequency of the first vibration system. Therefore, the movable mirror part 11 can be efficiently rotated around the Y axis by the first voltage V ₁ . That is, even if the vibration that the frame body portion 13 rotates about the Y axis is small, the rotation angle about the Y axis of the movable mirror portion 11 accompanying the vibration can be increased.

On the other hand, the second voltage V ₂ tries to attract one surface side (upper side) of the coil 31 to one magnetic pole 21 a side (S pole side) of the permanent magnet 21 and the other surface side of the coil 31 ( A magnetic field (this magnetic field is referred to as “magnetic field B1”) to be attracted to the other magnetic pole 21 b side (N pole side) of the permanent magnet 21 and one surface side (upper side) of the coil 31 is the permanent magnet 21. Magnetic field to be attracted to the other magnetic pole 21b side (N pole side) and the other surface side (lower side) of the coil 31 to be attracted to one magnetic pole 21a side (S pole side) of the permanent magnet 21. The magnetic field (this magnetic field is referred to as “magnetic field B2”) is switched alternately.

Here, as described above, the magnetic field generated between the soft magnetic body 22 and the soft magnetic body 23 by the permanent magnet 21 is inclined with respect to the X axis and the Y axis in plan view. Therefore, the magnetic field generated between the soft magnetic body 22 and the soft magnetic body 23 by the permanent magnet 21 has a component parallel to the Y axis. Therefore, by alternately switching between the magnetic field B1 and the magnetic field B2, the frame part 13 and the movable mirror part 11 together with the second voltage V2 while twisting and deforming the shaft parts 14a and 14b and the shaft parts 14c and 14d, respectively. It rotates around the X axis at a frequency of ₂ .
Also, the frequency of the second voltage V ₂ is set extremely low in comparison with the first frequency of the voltage V _1. The torsional resonance frequency of the second vibration system is designed to be lower than the torsional resonance frequency of the first vibration system. Therefore, it is possible to prevent the movable mirror 11 will be rotated around the Y axis at the frequency of the second voltage V _2.

As described above, by applying a voltage obtained by superimposing the first voltage V ₁ and the second voltage V ₂ to the coil 31, the movable mirror unit 11 is moved around the Y axis to the first voltage V _1. Can be rotated at the frequency of the _second voltage V ₂ around the X axis. As a result, the cost and size of the apparatus can be reduced, and the movable mirror portion 11 can be rotated around the X axis and the Y axis by an electromagnetic drive system (moving coil system). In addition, since the number of parts (permanent magnets and coils) constituting the drive source can be reduced, a simple and small configuration can be achieved.
According to the optical scanner 1 described above, power saving can be achieved in an actuator that can scan light two-dimensionally by a moving coil method.

Second Embodiment
Next, a second embodiment of the present invention will be described.
FIG. 6 is a cross-sectional view showing a second embodiment of the actuator (optical scanner) of the present invention, and FIG. 7 is for explaining the first soft magnetic body and the second soft magnetic body provided in the actuator shown in FIG. FIG. In the following, for convenience of explanation, the upper side in FIG. 6 is referred to as “upper” and the lower side is referred to as “lower”.

Hereinafter, the second embodiment will be described with a focus on the differences from the first embodiment described above, and the description of the same matters will be omitted. 6 and 7, the same reference numerals are given to the same configurations as those in the above-described embodiment.
The actuator of the present embodiment is the same as the actuator of the first embodiment described above except that the configuration of the coil and the support portion is different.

As shown in FIGS. 6 and 7, the optical scanner 1A of the second embodiment includes a support portion 15A that supports the second vibration system, and soft magnetic bodies 22A and 23A provided on the support portion 15A.
A concave portion 151 is formed on the upper surface of the support portion 15A of the present embodiment.
A soft magnetic body 22 </ b> A is installed in the recess 151. Thereby, even if the thickness t2 of the soft magnetic body 22A is thicker than the thickness t1 of the coil 31, the center of the soft magnetic body 22A and the center of the coil 31 coincide in the direction perpendicular to the X axis and the Y axis. Or you can get closer. In addition, the soft magnetic body 22A can be installed while ensuring a space for the light reflecting plate 113 to swing.
Further, the soft magnetic body 22A can be positioned with respect to the support portion 15A by making the inner periphery of the recess 151 contact the outer peripheral edge of the soft magnetic body 22A. In the present embodiment, the concave portion 151 and the soft magnetic body 22A have substantially the same shape in plan view.

Although not shown, the support 15 has a recess in which the soft magnetic body 23 </ b> A is installed, similar to the recess 151.
In the present embodiment, as shown in FIG. 7, the soft magnetic body 22A includes an edge 221A along the X axis, an edge 222A along the Y axis, and the vicinity of the shaft 14a inside the region S1. And the edge 221A coincides with the X axis in plan view, and the edge 222A is located on the region S4 side with respect to the Y axis.

Similarly, the soft magnetic body 23A includes an edge portion 231A along the X axis, an edge portion 232A along the Y axis, and an edge portion 233 formed by cutting the vicinity of the shaft portion 14d toward the inside of the region S2. The edge 231A coincides with the X axis in plan view, and the edge 232A is located on the region S3 side with respect to the Y axis.
Since the soft magnetic bodies 22A and 23A have the edge portions 223 and 233, even if the soft magnetic bodies 22A and 23A are installed in the concave portion of the support portion 15A as described above, the concave portions of the shaft portions 14a and 14d and the support portion 15A It is possible to prevent the mechanical strength of the connecting portion from being lowered.
Also with the optical scanner 1A of the second embodiment as described above, power saving can be achieved in an actuator (optical scanner) that scans light two-dimensionally by the moving coil method.

  Each of the optical scanners 1 and 1A described above is suitably applied to an optical scanner provided in an image display device such as an imaging display such as a projector, a head-up display (HUD), and a head-mounted display (HMD). can do. According to such an image display device, it is possible to achieve power saving of the optical scanner that scans light two-dimensionally by the moving coil method.

<Embodiment of Image Display Device>
FIG. 8 is a diagram schematically showing an embodiment of the image display device of the present invention.
In the present embodiment, a case where the optical scanner 1 is used as an optical scanner of an imaging display will be described as an example of an image display device. The longitudinal direction of the screen S is referred to as “lateral direction”, and the direction perpendicular to the longitudinal direction is referred to as “vertical direction”. Further, the X axis is parallel to the horizontal direction of the screen S, and the Y axis is parallel to the vertical direction of the screen S.

The image display device (projector) 9 includes a light source device (light source) 91 that emits light such as a laser, a plurality of dichroic mirrors 92A, 92B, and 92C, and the optical scanner 1.
The light source device 91 includes a red light source device 911 that emits red light, a blue light source device 912 that emits blue light, and a green light source device 913 that emits green light.

The dichroic mirrors 92A, 92B, and 92C are optical elements that synthesize light emitted from the red light source device 911, the blue light source device 912, and the green light source device 913, respectively.
Such an image display device 9 converts light emitted from the light source device 91 (red light source device 911, blue light source device 912, green light source device 913) based on image information from a host computer (not shown) to the dichroic mirror 92A. , 92B, and 92C are combined, and the combined light is two-dimensionally scanned by the optical scanner 1 to form a color image on the screen S.

During the two-dimensional scanning, the light reflected by the light reflecting portion 114 due to the rotation of the movable mirror portion 11 of the optical scanner 1 around the Y axis is scanned in the horizontal direction of the screen S (main scanning). On the other hand, the light reflected by the light reflecting portion 114 by the rotation of the movable mirror portion 11 of the optical scanner 1 around the X axis is scanned (sub-scanned) in the vertical direction of the screen S.
In FIG. 8, the light synthesized by the dichroic mirrors 92A, 92B, and 92C is scanned two-dimensionally by the optical scanner 1, and then the light is reflected by the fixed mirror 93 and then an image is formed on the screen S. However, the fixed mirror 93 may be omitted, and the screen S may be directly irradiated with light two-dimensionally scanned by the optical scanner 1.

Hereinafter, application examples of the image display apparatus will be described.
<Application Example 1 of Image Display Device>
FIG. 9 is a perspective view showing an application example 1 of the image display device of the present invention.
As shown in FIG. 9, the image display device 9 can be applied to a portable image display device 100.
The portable image display device 100 includes a casing 110 formed with dimensions that can be grasped by a hand, and an image display device 9 built in the casing 110. With this portable image display device 100, for example, a predetermined image can be displayed on a predetermined surface such as a screen or a desk.

In addition, the portable image display device 100 includes a display 120 that displays predetermined information, a keypad 130, an audio port 140, a control button 150, a card slot 160, and an AV port 170.
Note that the portable image display device 100 may have other functions such as a call function and a GSP reception function.

<Application Example 2 of Image Display Device>
FIG. 10 is a perspective view showing an application example 2 of the image display device of the present invention.
As shown in FIG. 10, the image display device 9 can be applied to a head-up display system 200.
In the head-up display system 200, the image display device 9 is mounted on a dashboard of an automobile so as to constitute a head-up display 210. With this head-up display 210, a predetermined image such as a guidance display to the destination can be displayed on the windshield 220, for example.
Note that the head-up display system 200 can be applied not only to automobiles but also to aircrafts, ships, and the like.

<Application Example 3 of Image Display Device>
FIG. 11 is a perspective view showing an application example 3 of the image display device of the present invention.
As shown in FIG. 11, the image display device 9 can be applied to a head mounted display 300.
That is, the head mounted display 300 includes glasses 310 and the image display device 9 mounted on the glasses 310. Then, the image display device 9 displays a predetermined image that is visually recognized by one eye on the display unit 320 provided in a portion that is originally a lens of the glasses 310.

The display unit 320 may be transparent or opaque. When the display unit 320 is transparent, the information from the image display device 9 can be used by being superimposed on the information from the real world.
Note that the head-mounted display 300 may be provided with two image display devices 9 so that images viewed with both eyes may be displayed on the two display units.

  The actuator, optical scanner, and image display device of the present invention have been described based on the illustrated embodiment, but the present invention is not limited to this. For example, in the optical scanner and the image display apparatus of the present invention, the configuration of each unit can be replaced with an arbitrary configuration having the same function, and other arbitrary configurations can be added.

Further, the present invention may be a combination of any two or more configurations (features) of the above embodiments.
In the above-described embodiment, the case where two first shaft portions (one pair) are provided has been described as an example. However, the present invention is not limited to this. For example, four first shaft portions (two pairs) are provided. It may be provided above.

In the above-described embodiment, the case where the first shaft portion extends in the direction parallel to the first axis has been described as an example. However, the present invention is not limited to this, and the first shaft portion is the first shaft. It may extend in a direction inclined with respect to.
In the above-described embodiment, the case where four second shaft portions (two pairs) are provided has been described as an example. However, the present invention is not limited to this. For example, two second shaft portions (one pair) are provided. Or six (3 pairs) or more may be sufficient.

In the above-described embodiment, the case where the second shaft portion extends in the direction parallel to the second axis has been described as an example. However, the present invention is not limited to this, and the second shaft portion is the second shaft. It may extend in a direction inclined with respect to.
In the above-described embodiment, the case where the widths of the first shaft portion and the second shaft portion are constant in the entire region in the longitudinal direction has been described as an example. However, the present invention is not limited to this, and the first shaft portion And the 2nd axial part may have a part from which width differs.

  Moreover, although embodiment mentioned above demonstrated as an example the case where a light reflecting plate covered the whole 1st axial part, the whole frame part, and the whole 2nd axial part by planar view, a light reflecting plate is planar view. If at least a part of the first shaft part (the end part on the base part side of the movable mirror part) is covered, the optical device as described above can be downsized, the area of the light reflecting plate can be increased, and the light reflecting plate can be flexibly deformed. It is possible to achieve effects such as prevention of stray light by the end of the first shaft portion on the base side.

In the above-described embodiment, the case where the light reflecting plate and the spacer are formed by processing the SOI substrate has been described as an example. However, the present invention is not limited to this. For example, the light reflecting plate and the spacer are formed from different substrates. May be.
The spacer between the light reflecting plate and the base may be a solder ball. In this case, for example, metal films may be formed on the light reflecting plate and the spacer side surfaces of the base, and these metal films may be bonded to each other via solder balls.

In the above-described embodiments, the case where the actuator of the present invention is applied to an optical scanner has been described as an example. However, the present invention is not limited to this, and the actuator of the present invention may be, for example, an optical switch, an optical attenuator or the like. It can also be applied to devices.
Further, in the above-described embodiment, the movable portion is arranged around the first axis and the second axis by providing a coil only in the frame body and applying a voltage obtained by superimposing two voltages having different frequencies to the coil. Although the case where each was swung was explained as an example, it is not limited to this. For example, the movable part is also provided with a coil, the voltage of the first frequency is applied to the coil of the movable part, and the voltage of the second frequency different from the first frequency is applied to the coil of the frame part. It can be swung around the first axis and around the second axis.

DESCRIPTION OF SYMBOLS 1 ... Optical scanner 1A ... Optical scanner 4 ... Voltage application part 7 ... Control part 9 ... Image display device 11 ... Movable mirror part 12a ... Shaft part 12b ... Shaft part 13 ... Frame part 14a ... Shaft part 14b ... Shaft part 14c ... Shaft part 14d ... Shaft part 15 ... Support part 15A ... Support part 21 ... Permanent magnet 21a ... Magnetic pole 21b ... Magnetic pole 22 ... Soft magnetic body 22A ... ···························································································································································································· Light source device 92A ... Dichroic mirror 92B ... Dichroic mirror 92C ... Dichroic mirror 93 ... Fixed mirror 100 ... Portable image display device 110 ... Casing 111 ... Base (movable part) 112 ... Pacer 113 ... Light reflector 114 ... Light reflector 115 ... Hard layer 120 ... Display 130 ... Keypad 140 ... Audio port 150 ... Control button 151 ... Recess 160 ... Card slot 170 ... Port 200 Head up display system 210 Head up display 220 Windshield 221 Edge 221A Edge 222 Edge 222A Edge 223 Edge 231 Edge 231A Edge 232 ... Edge 232A ... Edge 233 ... Edge 300 ... Head mounted display 310 ... Glasses 320 ... Display section 911 ... Red light source device 912 ... Blue light source device 913 ... Green light source device L1 ... Line segment L2 ... Line segment P ... Intersection S ... Screen S ‥‥ region (first region) S2 ‥‥ region (second region) S3 ‥‥ region S4 ‥‥ region T ₁ ‥‥ period T ₂ ‥‥ period t1 ‥‥ thickness t2 ‥‥ thickness V ₁ ‥ ··· First voltage V ₂ ··· Second voltage

Claims (12)

A movable part swingable around a first axis;
A first shaft portion that supports the movable portion in a swingable manner around the first axis;
A frame body part that supports the first shaft part and is swingable around a second axis that intersects the first axis;
A second shaft portion supporting the frame body portion so as to be swingable around the second axis;
A support portion for supporting the second shaft portion;
A coil provided in the frame part;
A permanent magnet for generating a magnetic field acting on the coil;
A first soft magnetic body and a second soft magnetic body provided in the support portion and forming a magnetic path between the permanent magnet and the coil;
Of the four regions of the support section divided by the first axis and the second axis in a plan view as viewed from a direction perpendicular to the first axis and the second axis, 1 When one region is a first region, and a region that is point-symmetric with respect to the intersection of the first axis and the second axis with respect to the first region is a second region, The actuator characterized in that the first soft magnetic body is located in the first region and the second soft magnetic body is located in the second region. The first soft magnetic body has a portion extending outside the first region across the first axis in the plan view, and on the first region side with respect to the second axis. Provided in
The second soft magnetic body has a portion extending out of the second region across the first axis in the plan view, and on the second region side with respect to the second axis. The actuator according to claim 1, which is provided on the actuator. The coil is provided on one surface side of the frame body portion,
The actuator according to claim 1 or 2, wherein each of the first soft magnetic body and the second soft magnetic body is provided on the same surface side as the coil of the support portion.   4. The first soft magnetic body and the second soft magnetic body each have a shape in which the width gradually decreases toward the coil side in the plan view. 5. The actuator described in 1.   The actuator according to any one of claims 1 to 4, wherein each of the first soft magnetic body and the second soft magnetic body has a plate shape.   The actuator according to any one of claims 1 to 5, wherein the support portion has a recess in which the first soft magnetic body and the second soft magnetic body are provided.   The reflection reduction part which reduces the reflectance of light is provided in the surface on the opposite side to the said support part of a said 1st soft magnetic body and a said 2nd soft magnetic body as described in any one of Claim 1 thru | or 6. The actuator described. A light reflecting plate fixed to the movable part and provided with a light reflecting part having light reflectivity;
The frame body portion is provided surrounding the movable portion,
The light reflecting plate is separated from the first shaft portion in the thickness direction of the light reflecting plate, and is provided so as to overlap with at least a part of the first shaft portion when viewed from the plate thickness direction. The actuator according to any one of claims 1 to 7. A voltage application unit for applying a voltage to the coil;
The voltage application unit includes:
A first voltage generator for generating a first voltage of a first frequency;
A second voltage generator for generating a second voltage of a second frequency different from the first frequency;
A voltage superimposing unit that superimposes the first voltage and the second voltage;
9. The movable portion is swung around the first axis at the first frequency and swung around the second axis at the second frequency. 9. Actuator. A movable part swingable around a first axis;
A light reflecting plate fixed to the movable part and provided with a light reflecting part having light reflectivity;
A first shaft portion that supports the movable portion in a swingable manner around the first axis;
A frame body part that supports the first shaft part and is swingable around a second axis that intersects the first axis;
A second shaft portion supporting the frame body portion so as to be swingable around the second axis;
A support portion for supporting the second shaft portion;
A coil provided in the frame part;
A permanent magnet for generating a magnetic field acting on the coil;
A first soft magnetic body and a second soft magnetic body provided in the support portion and forming a magnetic path between the permanent magnet and the coil;
Of the four regions of the support section divided by the first axis and the second axis in a plan view as viewed from a direction perpendicular to the first axis and the second axis, 1 When one region is a first region, and a region that is point-symmetric with respect to the intersection of the first axis and the second axis with respect to the first region is a second region, The optical scanner, wherein the first soft magnetic body is located in the first region, and the second soft magnetic body is located in the second region. A movable part swingable around a first axis;
A light reflecting plate fixed to the movable part and provided with a light reflecting part having light reflectivity;
A first shaft portion that supports the movable portion in a swingable manner around the first axis;
A frame body part that supports the first shaft part and is swingable around a second axis that intersects the first axis;
A second shaft portion supporting the frame body portion so as to be swingable around the second axis;
A support portion for supporting the second shaft portion;
A coil provided in the frame part;
A permanent magnet for generating a magnetic field acting on the coil;
A first soft magnetic body and a second soft magnetic body provided in the support portion and forming a magnetic path between the permanent magnet and the coil;
Of the four regions of the support section divided by the first axis and the second axis in a plan view as viewed from a direction perpendicular to the first axis and the second axis, 1 When one region is a first region, and a region that is point-symmetric with respect to the intersection of the first axis and the second axis with respect to the first region is a second region, The image display device, wherein the first soft magnetic body is located in the first region, and the second soft magnetic body is located in the second region. A movable part swingable around a first axis;
A light reflecting plate fixed to the movable part and provided with a light reflecting part having light reflectivity;
A first shaft portion that supports the movable portion in a swingable manner around the first axis;
A frame body part that supports the first shaft part and is swingable around a second axis that intersects the first axis;
A second shaft portion supporting the frame body portion so as to be swingable around the second axis;
A support portion for supporting the second shaft portion;
A coil provided in the frame part;
A permanent magnet for generating a magnetic field acting on the coil;
A first soft magnetic body and a second soft magnetic body provided in the support portion and forming a magnetic path between the permanent magnet and the coil;
Of the four regions of the support section divided by the first axis and the second axis in a plan view as viewed from a direction perpendicular to the first axis and the second axis, 1 When one region is a first region, and a region that is point-symmetric with respect to the intersection of the first axis and the second axis with respect to the first region is a second region, The head-mounted display, wherein the first soft magnetic body is located in the first region and the second soft magnetic body is located in the second region.

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