JP2014021424A - Optical device, image display unit, and method of manufacturing optical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical device capable of reducing a breakage of a shaft part, an image display unit, and a method of manufacturing the optical device.SOLUTION: The optical device includes a movable part 11 having a base 111 and a reflector 113 that is disposed via a spacer 112 disposed on a first surface of the base 111 and has a reflection plane 114 for reflecting light, shaft parts 12a and 12b for supporting the movable part 11 oscillatably about a first shaft, a frame body part 13 oscillatable about a second shaft crossing the first shaft, and a permanent magnet 21A disposed in the frame body part 13. The base 111 is connected to the frame body part 13 via the shaft parts 12a and 12b, and projections 131A and 131B are disposed on a second surface on the opposite side to the first surface of the base 111.

Description

  The present invention relates to an optical device, an image display apparatus including the optical device, and a method for manufacturing the optical device.

  Conventionally, for example, an optical device is known in which a reflector and a base are manufactured separately and the reflector is fixed to the base with an adhesive or the like. (For example, refer to Patent Document 1.)

JP 2012-58560 A

  However, in the above optical device, when the reflector is mounted on the base, the base is pushed by the reflector, and the shaft that supports the base so as to be swingable is deformed or the shaft is damaged. There was a problem.

  The present invention has been made to solve the above-described problems, and can be realized as the following application examples.

  Application Example 1 An optical device according to this application example includes a base, and a movable part having a reflecting plate that is provided via a spacer provided on the first surface of the base and has a reflecting surface that reflects light. A shaft portion that supports the movable portion so as to be swingable around a first axis, a frame body portion that is swingable around a second axis that intersects the first axis, and the frame body portion. Provided with a permanent magnet, wherein the base and the frame body part are connected by the shaft part, and a convex part is provided on a second surface of the base opposite to the first surface. It is characterized by.

  According to this application example, when the reflecting plate is fixed to the base, the amount by which the base is pushed down is regulated by the convex portion. Thereby, the deformation amount of the shaft portion is reduced. Therefore, it is possible to provide a highly reliable optical device that can reduce breakage of the shaft portion and the like.

  Application Example 2 In the optical device according to the application example described above, the base portion, the shaft portion, and the frame body portion are formed using a device layer of a silicon on insulator (SOI) substrate, and the convex portion is It is preferably formed using a handle layer of an SOI substrate.

  Here, the silicon on insulator (SOI) substrate refers to a substrate in which a first Si layer (device layer), a SiO 2 layer (box layer), and a second Si layer (handle layer) are stacked.

  According to this application example, since the SOI substrate can be finely processed by etching, the base portion, the frame body portion, the shaft portion, and the convex portion are formed using the SOI substrate, so that these dimensional accuracy is excellent. Can be. Further, the convex portion can be easily formed by using the handle layer of the SOI substrate.

  Application Example 3 In the optical device according to the application example, it is preferable that the convex portion is provided in a thickness direction of the base portion.

  According to this application example, since the convex portion is provided in the thickness direction of the base portion, the direction in which the reflecting plate is fixed to the base portion and the protruding direction of the convex portion coincide. Thereby, when the reflecting plate is fixed to the base, the amount by which the base is pushed down can be reduced.

  Application Example 4 In the optical device according to the application example, the permanent magnet is provided so as to straddle the base portion, and the length of the convex portion in the thickness direction of the base portion is the thickness direction of the base portion. It is preferable that it is more than the maximum length of the said permanent magnet.

  According to this application example, since the length of the convex portion in the thickness direction of the base portion is equal to or greater than the maximum length of the permanent magnet in the thickness direction of the base portion, when the reflector is fixed to the base portion, the base portion becomes a permanent magnet. Collision can be reduced.

  Application Example 5 In the optical device according to the application example described above, it is preferable that the convex portion is provided at a position away from the permanent magnet.

  According to this application example, when the movable portion swings around the first axis, it is possible to reduce the collision of the convex portion with the permanent magnet. Therefore, the swing range of the movable part can be expanded.

  Application Example 6 In the optical device according to the application example described above, it is preferable that a plurality of the protrusions are provided on the second surface, and the lengths of the protrusions in the thickness direction of the base are equal. .

  According to this application example, a plurality of convex portions are provided on the second surface of the base portion, and the lengths of the respective convex portions in the thickness direction of the base portion are equal. Therefore, when the reflector is fixed to the base portion, the base portion is inclined. Thus, the deformation of the shaft portion can be reduced. Here, in this application example, “the lengths of the convex portions are equal” is not limited to a completely equal state, and may be equal as long as the difference is within a predetermined range. For example, if the difference between the lengths of the convex portions is ± 10% or less, they can be equal.

  Application Example 7 The optical device according to the application example includes a coil and a voltage applying unit that applies a voltage to the coil, and the permanent magnet includes the first shaft and the coil in a plan view. The voltage application means is arranged in a direction inclined with respect to a second axis, and the voltage application means includes a first voltage having a first frequency that causes the movable part to swing around the first axis, and the frame body part as described above. It is preferable that a voltage obtained by superimposing a second voltage of a second frequency that swings around the second axis is applied to the coil.

  According to this application example, the reflecting plate can be swung around the first axis and the second axis while reducing the number of parts.

  Application Example 8 An image display device according to this application example is provided with a base, a reflector provided on a first surface of the base, and provided with a reflective surface having light reflectivity, and A movable portion having one end connected to the base, a shaft portion supporting the movable portion so as to be swingable about a first axis, and the other end of the shaft portion being connected, A frame body portion swingable around a second axis that intersects the axis, and a permanent magnet provided on the frame body portion, on a second surface opposite to the first surface of the base portion An optical device having a convex portion and a light source that emits light to the optical device are provided.

  According to this application example, when the reflecting plate is fixed to the base, the amount by which the base is pushed down is regulated by the convex portion. Thereby, the deformation amount of the shaft portion is reduced. Therefore, it is possible to provide a highly reliable image display device that can reduce breakage of the shaft portion and the like.

  Application Example 9 An optical device manufacturing method according to this application example uses a device layer of a silicon on insulator (SOI) substrate to connect a base portion, a frame body portion, and the base portion and the frame body portion. A step of forming a shaft portion, a step of forming a convex portion on the base portion using a handle layer of the SOI substrate, a step of fixing a permanent magnet to the frame body portion, and a reflecting surface for reflecting light And a step of fixing the reflecting plate to the surface of the base portion on the device layer side through a spacer provided on the reflecting plate.

  Here, the silicon on insulator (SOI) substrate refers to a substrate in which a first Si layer (device layer), a SiO 2 layer (box layer), and a second Si layer (handle layer) are stacked.

  According to this application example, when the reflecting plate is fixed to the base, the amount by which the base is pushed down is regulated by the convex portion. Thereby, the deformation amount of the shaft portion is reduced. Therefore, it is possible to provide a highly reliable manufacturing method of an optical device that can reduce breakage of the shaft portion and the like.

  Application Example 10 An optical device manufacturing method according to this application example uses a device layer of a silicon on insulator (SOI) substrate to connect a base portion, a frame body portion, and the base portion and the frame body portion. A step of forming a shaft portion, a step of forming a convex portion on the base portion using a handle layer of the SOI substrate, a step of fixing a permanent magnet to the frame body portion, and the device layer of the base portion A step of fixing a spacer to a side surface, and a step of fixing a reflecting plate having a reflecting surface for reflecting light to a surface on the opposite side of the surface fixed to the base of the spacer. To do.

  According to this application example, when the reflecting plate is fixed to the base, the amount by which the base is pushed down is regulated by the convex portion. Thereby, the deformation amount of the shaft portion is reduced. Therefore, it is possible to provide a highly reliable manufacturing method of an optical device that can reduce breakage of the shaft portion and the like.

  Application Example 11 In the manufacturing method of the optical device according to the application example, in the step of forming the convex portion, the length of the convex portion in the thickness direction of the base portion is the length in the thickness direction of the base portion. It is preferable to form the convex portion so as to be longer than the maximum length of the permanent magnet.

  According to this application example, since the length of the convex portion in the thickness direction of the base portion is equal to or greater than the maximum length of the permanent magnet in the thickness direction of the base portion, when the reflector is fixed to the base portion, the base portion becomes a permanent magnet. Collision can be reduced.

FIG. 3 is a plan view showing the configuration of the optical scanner according to the first embodiment. FIG. 3 is a cross-sectional view illustrating a configuration of the optical scanner according to the first embodiment. FIG. 3 is a cross-sectional view illustrating a configuration of the optical scanner according to the first embodiment. The block diagram which shows the structure of a drive means. An explanatory view showing an example of generated voltage. FIG. 6 is a process diagram illustrating a method for manufacturing the optical scanner according to the first embodiment. FIG. 6 is a process diagram illustrating a method for manufacturing the optical scanner according to the first embodiment. FIG. 6 is a plan view illustrating a configuration of an optical scanner according to a second embodiment. FIG. 6 is a cross-sectional view illustrating a configuration of an optical scanner according to a second embodiment. FIG. 6 is a cross-sectional view illustrating a configuration of an optical scanner according to a second embodiment. 1 is a schematic diagram illustrating a configuration of an image display device. The perspective view which shows the application example 1 of an image display apparatus. The perspective view which shows the application example 2 of an image display apparatus. The perspective view which shows the application example 3 of an image display apparatus.

  Hereinafter, preferred embodiments 1 and 2 of an optical device and an image display apparatus according to the present invention will be described with reference to the accompanying drawings. In the following drawings, the scale of each member or the like is shown differently from the actual scale so as to make each member or the like recognizable. In the following first and second embodiments, a case where an optical device is applied to an optical scanner will be described as a representative example.

<Embodiment 1>
1 is a plan view showing the configuration of an optical scanner as an optical device, FIG. 2 is a cross-sectional view (cross-sectional view along the X axis) showing the configuration of the optical scanner according to Embodiment 1, and FIG. FIG. 4 is a block diagram illustrating a configuration of a driving unit, and FIG. 5 is an explanatory diagram illustrating an example of a generated voltage. 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”.

As shown in FIGS. 1 to 3, the optical scanner 1 includes a movable portion 11, a pair of shaft portions 12a and 12b (first shaft portion), a frame body portion 13, and a pair of shaft portions 14a. 14 b (second shaft portion), support frame portion 16, support portion 15, permanent magnet 21 </ b> A, coil 31, magnetic core 32, and voltage application means 4.
Here, the movable portion 11 and the pair of shaft portions 12a and 12b are the first that swings (reciprocates) the movable portion 11 around the Y axis (first axis) about the shaft portions 12a and 12b. Configure the vibration system. Further, the movable portion 11, the pair of shaft portions 12a and 12b, the frame portion 13, the pair of shaft portions 14a and 14b, and the permanent magnet 21A are arranged on the X axis (the second axis) with the pair of shaft portions 14a and 14b as axes. The second vibration system is configured to swing (reciprocate) the frame body portion 13 around the axis.
The permanent magnet 21A, the coil 31, and the voltage application means 4 drive the first vibration system and the second vibration system described above (that is, the drive means for swinging the movable portion 11 around the X axis and the Y axis). Configure.

Hereinafter, each part of the optical scanner 1 will be described in detail sequentially.
The movable part 11 includes a base 111 and a reflector 113 fixed to the base 111 via a spacer 112.
A reflective surface 114 that reflects light is provided on the top surface of the reflective plate 113.

The reflection plate 113 is separated from the shaft portions 12a and 12b in the thickness direction, and overlaps the shaft portions 12a and 12b when viewed from the thickness direction of the base portion 111 (hereinafter also referred to as “plan view”). Is provided.
Therefore, the area of the plate surface of the 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 can be shortened.

For this reason, the optical scanner 1 can be downsized even if the area of the reflecting plate 113 is increased.
Further, since the reflecting plate 113 is provided to be separated from the shaft portions 12a and 12b in the thickness direction, that is, the shaft portions 12a and 12b are not directly connected to the side surfaces of the reflecting plate 113. It is possible to prevent or reduce the stress due to the torsional deformation of the shaft portions 12a and 12b from reaching the reflecting plate 113 when the shaft 113 swings, and as a result, it is possible to reduce the bending of the reflecting plate 113.

A hard layer 115 is provided on the lower surface of the reflection plate 113.
The hard layer 115 is made of a material harder than the constituent material of the reflector 113 main body. Thereby, the rigidity of the reflecting plate 113 can be increased. Therefore, it is possible to prevent or reduce the bending when the reflecting plate 113 swings. Further, the thickness of the reflecting plate 113 can be reduced, and the moment of inertia when the 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 reflector 113 main body. For example, diamond, carbon nitride film, crystal, sapphire, lithium tantalate, Although potassium niobate can be used, 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 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.

  Further, the lower surface of the reflecting plate 113 is fixed to the upper surface (first surface) 111 a of the base 111 via the spacer 112. Thereby, the reflecting plate 113 can be swung around the Y axis while preventing contact with the shaft portions 12a and 12b, the frame body portion 13 and the shaft portions 14a and 14b. The area of the base 111 in plan view is preferably as small as possible as long as the base 111 can support the reflector 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 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 portion 11 described above in a plan view. In other words, the base 111 of the movable portion 11 is provided inside the frame body portion 13 having a frame shape. The frame body portion 13 is supported by the support frame portion 16 via the shaft portions 14a and 14b. Further, the base 111 of the movable portion 11 is supported by the frame body portion 13 through 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 part 11, and axial part 12a, 12b by planar view. Thereby, the size of the frame body portion 13 is reduced while allowing the vibration of the first vibration system configured by the movable portion 11 and the shaft portions 12a and 12b, that is, the swing of the movable portion 11 around the Y axis. be able to. 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 and 12b and the shaft portions 14a and 14b can be elastically deformed. The shaft portions 12a and 12b connect the base portion 111 and the frame body portion 13 so that the movable portion 11 can be rotated (swinged) around the Y axis (first axis). Further, the shaft portions 14a and 14b have the frame body portion 13 and the support frame portion 16 so that the frame body portion 13 can be rotated (swinged) around the X axis (second axis) orthogonal to the Y axis. Are connected.

  The shaft portions 12 a and 12 b are disposed so as to face each other with the base portion 111 interposed therebetween. 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.

  Each of the shaft portions 12a and 12b is torsionally deformed as the movable portion 11 swings around the Y axis. The shaft portions 14 a and 14 b are disposed so as to face each other with the frame body portion 13 interposed therebetween. Each of the shaft portions 14a and 14b has a longitudinal shape extending in the direction along the X axis. Each of the shaft portions 14 a and 14 b has one end connected to the frame body portion 13 and the other end connected to the support frame portion 16. In addition, the shaft portions 14a and 14b are arranged so that the central axis coincides with the X axis.

  In such shaft portions 14a and 14b, the shaft portions 14a and 14b are torsionally deformed as the frame body portion 13 swings around the X axis. As described above, the movable portion 11 can be swung around the Y axis, and the frame body portion 13 can be swung around the X axis. It can be swung (rotated) around the axis. Note that the base 111, the shaft portions 12a and 12b, the frame body portion 13, the shaft portions 14a and 14b, and the support frame portion 16 as described above are integrally formed.

  As shown in FIG. 1, the permanent magnet 21 </ b> A is provided on the frame body portion 13 with one magnetic pole and the other magnetic pole sandwiching (stranding) the X axis in plan view. That is, it is provided so as to straddle the base 111. Further, it is magnetized in a direction inclined with respect to the X axis and the Y axis. In the present embodiment, the permanent magnet 21A has a longitudinal shape (bar shape) extending in a direction inclined with respect to the X axis and the Y axis. The permanent magnet 21A is magnetized in the longitudinal direction. That is, the permanent magnet 21A is magnetized so that one end portion is an S pole and the other end portion is an N pole.

  The inclination angle θ in the magnetization direction (extending direction) of the permanent magnet 21A with respect to the X axis is not particularly limited, but is preferably 30 ° or more and 60 ° or less, and more preferably 45 ° or more and 60 ° or less. 45 ° is more preferable. Thus, by providing the permanent magnet 21A, the movable part 11 can be smoothly and reliably rotated around the X axis. On the other hand, if the inclination angle θ is less than the lower limit value, the movable portion 11 can be sufficiently rotated around the X axis depending on various conditions such as the strength of the voltage applied to the coil 31 by the voltage applying means 4. It may not be possible to On the other hand, if the inclination angle θ exceeds the upper limit value, the movable part 11 may not be able to be sufficiently rotated around the Y axis depending on various conditions.

  As such a permanent magnet 21A, 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 permanent magnet 21A is provided with a recess 21a so that the permanent magnet 21A and the movable portion 11 do not interfere (collision). That is, a gap is formed between the second surface 111b of the base 111 and the permanent magnet 21A facing the second surface 111b.

  In addition, a convex portion 131 is provided on the lower surface (second surface) 111 b of the base portion 111. In the present embodiment, two convex portions 131A and 131B are provided. Therefore, as will be described later, when the reflecting plate 113 is attached (fixed) to the base 111, the amount by which the base 111 is pushed down is restricted by the convex 131.

  Moreover, it is preferable that the convex part 131 is provided toward the thickness direction of the base part, that is, the downward direction (gravity direction) straight from the base part 111. Thereby, the direction in which the reflecting plate 113 is attached coincides with the protruding direction of the convex portion 131.

  Moreover, it is preferable that the convex part 131 is provided with two or more. Thereby, the stability at the time of attaching the reflecting plate 113 to the base 111 improves.

  Further, it is preferable that the plurality of convex portions 131 are provided at positions where the center of the lower surface (second surface) of the base portion 111 is symmetric with respect to the origin. Thereby, the stability when attaching the reflecting plate 113 to the base 111 is further improved.

  Moreover, it is preferable that the length of the some convex part 131 in the thickness direction (up-down direction) of the base 111 is equal. Thereby, the stability when attaching the reflecting plate 113 to the base 111 is further improved.

  Moreover, it is preferable that the length of the convex part 131 in the thickness direction (up-down direction) of the base 111 is not less than the maximum length of the permanent magnet 21A in the up-down direction. Here, the maximum length of the permanent magnet 21A in the vertical direction is L in FIG. Thereby, when attaching the reflecting plate 113 to the base 111, it can reduce that the base 111 collides with 21 A of permanent magnets.

  Moreover, it is preferable that the convex part 131 is provided in the position away from the permanent magnet 21A. Thereby, when the movable part 11 rock | fluctuates around a Y-axis (1st axis | shaft), it can reduce that the convex part 131 collides with 21 A of permanent magnets.

  A coil 31 is provided directly below the permanent magnet 21A. That is, the coil 31 is provided so as to face the lower surface of the frame body portion 13. Thereby, the magnetic field generated from the coil 31 can be efficiently applied to the permanent magnet 21A. Thereby, power saving and size reduction of the optical scanner 1 can be achieved. In the present embodiment, the coil 31 is provided by being wound around the magnetic core 32. Thereby, the magnetic field generated by the coil 31 can be efficiently applied to the permanent magnet 21A. The magnetic core 32 may be omitted.

  Such a coil 31 is electrically connected to the voltage applying means 4. Then, a voltage is applied to the coil 31 by the voltage application unit 4, thereby generating a magnetic field having a magnetic flux orthogonal to the X axis and the Y axis from the coil 31. As shown in FIG. 4, the voltage applying means 4 includes a first voltage generating unit 41 that generates a first voltage V1 for rotating the movable unit 11 around the Y axis, and a movable unit 11 around the X axis. And a voltage superimposing unit 43 that superimposes the first voltage V1 and the second voltage V2, and a voltage superimposing unit 43. The voltage superimposed in (1) is applied to the coil 31.

  As shown in FIG. 5A, the first voltage generator 41 generates a first voltage V1 (horizontal scanning voltage) that periodically changes in a cycle T1. In other words, the first voltage generator 41 generates the first voltage V1 having the first frequency (1 / T1). The first voltage V1 has a waveform like a sine wave. Therefore, the optical scanner 1 can perform main scanning of light effectively. Note that the waveform of the first voltage V1 is not limited to this.

  The first frequency (1 / T1) is not particularly limited as long as it is 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 portion 11 and the pair of shaft portions 12a and 12b. ing. 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 part 11 around the Y axis can be increased.

  On the other hand, as shown in FIG. 5B, the second voltage generator 42 generates a second voltage V2 (vertical scanning voltage) that periodically changes at a period T2 different from the period T1. . In other words, the second voltage generator 42 generates the second voltage V2 having the second frequency (1 / T2). The second voltage V2 has a sawtooth waveform. Therefore, the optical scanner 1 can effectively perform vertical scanning (sub-scanning) of light. Note that the waveform of the second voltage V2 is not limited to this.

  The second frequency (1 / T2) is not particularly limited as long as it is different from the first frequency (1 / T1) and is suitable for vertical scanning, but is preferably 30 to 120 Hz (about 60 Hz). . As described above, the frequency of the second voltage V2 is set to about 60 Hz, and the frequency of the first voltage V1 is set to 10 to 40 kHz as described above, so that the movable part 11 can be moved at a frequency suitable for drawing on the display. It can be rotated around each of two axes (X axis and Y axis) orthogonal to each other. However, the combination of the frequency of the first voltage V1 and the frequency of the second voltage V2 is not particularly limited as long as the movable portion 11 can be rotated around the X axis and the Y axis.

  In the present embodiment, the frequency of the second voltage V2 is the second composed of the movable portion 11, the pair of shaft portions 12a and 12b, the frame body portion 13, the pair of shaft portions 14a and 14b, and the permanent magnet 21A. The vibration system (torsional vibration system) is adjusted to have a frequency different from the torsional resonance frequency (resonance frequency). The frequency (second frequency) of the second voltage V2 is preferably smaller than the frequency (first frequency) of the first voltage V1. That is, the period T2 is preferably longer than the period T1. Thereby, the movable part 11 can be rotated around the X axis at the second frequency while being rotated around the Y axis 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 part 11 can be more smoothly rotated at the frequency of the second voltage V2 around the X axis while being rotated at the frequency of the first voltage V1 around the Y axis. On the other hand, when f1 ≦ f2, the vibration of the first vibration system may occur due to the second frequency.

  The first voltage generation unit 41 and the second voltage generation unit 42 are connected to the control unit 7 and driven based on signals 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 as described above. 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 <b> 1 from the first voltage generator 41 and receives the second voltage V <b> 2 from the second voltage generator 42, and superimposes and applies these voltages 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 V1 is set equal to the torsional resonance frequency of the first vibration system, and the frequency of the second voltage V2 is the second vibration frequency. It is set to a value different from the torsional resonance frequency of the system and smaller than the frequency of the first voltage V1 (for example, the frequency of the first voltage V1 is 18 kHz and the frequency of the second voltage V2 is 60Hz).

  For example, the first voltage V 1 as shown in FIG. 5A and the second voltage V 2 as shown in FIG. 5B are superimposed by the voltage superimposing unit 43, and the superimposed voltage is applied to the coil 31. Apply. Then, the first voltage V1 tries to attract one end (N pole) of the permanent magnet 21A to the coil 31, and the magnetic field tries to separate the other end (S pole) of the permanent magnet 21A from the coil 31. (Referred to as “magnetic field A1”) and one end (N pole) of the permanent magnet 21A to be separated from the coil 31, and the other end (S pole) of the permanent magnet 21A is to be attracted to the coil 31. (Referred to as “magnetic field A2”) alternately.

  Here, in the plan view of FIG. 1, the south pole of the permanent magnet 21A is located on one side and the north pole of the permanent magnet 21A is located on the other side across the Y axis. Therefore, by alternately switching between the magnetic field A1 and the magnetic field A2, vibration having a torsional vibration component around the Y axis is excited in the frame body portion 13 and the shaft portions 12a and 12b are twisted and deformed along with the vibration. Meanwhile, the movable portion 11 rotates around the Y axis at the frequency of the first voltage V1. The frequency of the first voltage V1 is equal to the torsional resonance frequency of the first vibration system. Therefore, the movable part 11 can be efficiently rotated around the Y axis by the first voltage V1. That is, even if the vibration having the torsional vibration component around the Y axis of the frame portion 13 described above is small, the rotation angle of the movable portion 11 around the Y axis associated with the vibration can be increased.

  On the other hand, the second voltage V2 attempts to attract one end (N pole) of the permanent magnet 21A to the coil 31 and to magnetically separate the other end (S pole) of the permanent magnet 21A from the coil 31. (Referred to as “magnetic field B1”) and a magnetic field in which one end (N pole) of the permanent magnet 21A is to be separated from the coil 31 and the other end (S pole) of the permanent magnet 21A is to be attracted to the coil 31. (Referred to as “magnetic field B2”) alternately.

  Here, in the plan view of FIG. 1, the N pole of the permanent magnet 21 </ b> A is located on one side and the S pole of the permanent magnet 21 </ b> A is located on the other side across the X axis. Therefore, by alternately switching the magnetic field B1 and the magnetic field B2, the frame part 13 together with the movable part 11 is rotated around the X axis at the frequency of the second voltage V2 while twisting and deforming the shaft parts 14a and 14b. Rotate. Further, the frequency of the second voltage V2 is set to be extremely lower than the frequency of the first voltage V1. 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 part 11 from rotating around the Y axis at the frequency of the second voltage V2.

  As described above, in the optical scanner 1, the movable unit 11 is moved around the Y axis by applying the voltage obtained by superimposing the first voltage V 1 and the second voltage V 2 to the coil 31. Can be rotated at the frequency of the second voltage V2 around the X axis. As a result, the cost and size of the apparatus can be reduced, and the movable portion 11 can be rotated around the X axis and the Y axis by an electromagnetic drive system (moving magnet 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. Further, since the coil 31 is separated from the vibration system of the optical scanner 1, adverse effects due to heat generation of the coil 31 with respect to the vibration system can be prevented.

  Next, the method for manufacturing the optical scanner 1 according to the present embodiment will be described with reference to FIGS. 6 and 7 are process diagrams (cross-sectional views along the X axis) showing the method of manufacturing the optical scanner according to the first embodiment. In the following description, the upper side in FIGS. 6 and 7 is referred to as “upper” and the lower side is referred to as “lower”.

  First, as shown in FIG. 6A, a substrate 400 in which a first Si layer (device layer) 400a, a SiO2 layer (box layer) 400b, and a second Si layer (handle layer) 400c are prepared. . This substrate is generally referred to as a Silicon On Insulator (SOI) substrate 400. Hereinafter, the base 111, the first shaft portions 12a and 12b, the frame body portion 13, the second shaft portions 14a and 14b, and the support frame portion 16 are formed by the first Si layer 400a, and the SiO2 layer 400b and the second The convex portions 131A and 131B and the support portion 15 are formed by the Si layer 400c.

  Next, as shown in FIG. 6B, an oxide film 500 is formed on the lower surface side of the second Si layer 400c using a method such as thermal oxidation.

  Next, as shown in FIG. 6C, a resist 600 is applied to the surface of the oxide film 500.

  Next, as shown in FIG. 6D, an etching mask 601 for the oxide film 500 is formed by a photolithography process.

  Next, as shown in FIG. 6E, the oxide film 500 is etched to form an oxide film mask 501. As an etching method, chemical wet etching using buffered hydrofluoric acid (BHF) or the like, or physical etching, for example, plasma etching, reactive ion etching, beam etching, photo-assisted etching, or the like may be used. In addition, one or more of the above etching methods can be used in combination. It should be noted that the same method can also be used for etching in each step below.

  Next, the etching mask 601 is removed, and a new resist 700 is applied to the upper surface side of the first Si layer 400a in order to pattern the first Si layer 400a, as shown in FIG.

  Next, as shown in FIG. 6G, an etching mask 701 for the first Si layer 400a is formed by a photolithography process. For alignment in the photolithography process, alignment with the already formed oxide film mask 501 (so-called double-sided alignment) is performed.

  Next, as shown in FIG. 7H, the first Si layer 400a is etched. At this time, the SiO2 layer 400b functions as an etching stop layer. In this step, a DRIE (Deep Reactive Ion Etching) apparatus is used as a dry etching apparatus in order to form a structure having a high aspect ratio. Thereafter, the etching mask 701 is removed.

  Next, as shown in FIG. 7I, the second Si layer 400c is processed by DRIE. At this time, the SiO2 layer 400b functions as an etching stop layer.

  Next, as shown in FIG. 7J, the SiO2 layer 400b is wet etched with hydrofluoric acid. At this time, the oxide film mask 501 is also removed. Here, the convex portions 131A and 131B and the support portion 15 made of the SiO2 layer 400b and the second Si layer 400c are formed. Thus, the convex portions 131A and 131B can be easily formed by leaving a part of the handle layer located below the base portion 111.

  At that time, the length of the convex portions 131A and 131B in the thickness direction (vertical direction) of the base 111 is set to be equal to or greater than the maximum length in the vertical direction of the permanent magnet 21A to be joined to the frame body portion 13 in the next step. preferable. Thereby, when attaching the reflecting plate 113 to the base 111, it can reduce that the base 111 collides with 21 A of permanent magnets.

  Furthermore, it is preferable that the length of the convex portions 131A and 131B in the vertical direction is equal to or longer than the length of the support portion 15 in the vertical direction. Thereby, when attaching the reflecting plate 113 to the base 111, the amount by which the base 111 is pushed down by the convex portions 131A and 131B can be further reduced.

  The base 111, the first shaft portions 12a and 12b, the frame body portion 13, the second shaft portions 14a and 14b, and the support frame portion 16 are formed by wet etching using hydrofluoric acid.

  Next, as shown in FIG. 3 and FIG. 7 (k), the permanent magnet 21 </ b> A is joined (installed) to the lower surface of the frame body portion 13. Although it does not specifically limit as a joining method of 21 A of permanent magnets, and the frame part 13, For example, the joining method using bonding agents (not shown), such as an adhesive agent and a brazing agent, can be used. Further, the permanent magnet 21A may be joined (installed) with a hard magnetic material (that is, the permanent magnet 21A) that has already been magnetized, or may be magnetized using a magnetizer or the like after joining.

  Next, as shown in FIG. 7L, the device to which the permanent magnet 21A is bonded is placed on the base 800, and the reflector 113 is attached to the surface of the base 111 on the device layer side via the spacer 112. Therefore, when the reflecting plate 113 is attached (fixed) to the base 111, the amount by which the base 111 is pushed down is regulated by the convex portions 131A and 131B. Thereby, the deformation amount of the shaft portions 12a and 12b connected to the base portion 111 is reduced.

  Here, in this embodiment, the spacer 112 and the reflection plate 113 are also formed by etching the SOI substrate. The spacer 112 is composed of a laminate composed of the SiO2 layer and the second Si layer of the SOI substrate. Further, the reflection plate 113 is composed of a first Si layer of an SOI substrate. Thus, by forming the spacer 112 and the reflection plate 113 using the SOI substrate, the spacer 112 and the reflection plate 113 joined to each other can be manufactured easily and with high accuracy.

  In addition, a method for joining the spacer 112 and the base 111 is not particularly limited. For example, a joining method using a joining material (not shown) such as an adhesive or a brazing material can be used. In addition, a metal film is formed as the reflecting surface 114 on the upper surface of the reflecting plate 113. Examples of a method for forming such a metal film include dry plating methods such as vacuum deposition, sputtering, and ion plating, wet plating methods such as electrolytic plating and electroless plating, thermal spraying methods, and metal foil bonding.

  As described above, according to the optical scanner 1 according to the first embodiment, the following effects can be obtained.

  Since the convex portion 131 is provided on the lower surface (second surface) 111 b of the base portion 111, the amount by which the base portion 111 is pushed down is regulated by the convex portion 131 when the reflector 113 is attached (fixed) to the base portion 111. . Thereby, the deformation amount of the shaft portions 12a and 12b connected to the base portion 111 is reduced. Therefore, damage to the shaft portions 12a and 12b can be reduced. Furthermore, by providing the convex portion 131, the position of the center of gravity of the movable portion 11 can be adjusted so as to be close to or coincide with the central axes of the shaft portions 12a and 12b. Thereby, the first vibration system and the second vibration system are driven in a state in which the position of the center of gravity of the movable portion 11 is deviated from the central axis of the shaft portions 12a and 12b, and the composite stress is applied to the shaft portions 12a and 12b. Can be reduced. Therefore, it is possible to reduce damage to the shaft portions 12a and 12b.

  Moreover, since the convex part 131 is provided toward the thickness direction of the base part, that is, the downward direction (gravity direction) straight from the base part 111, the direction in which the reflecting plate 113 is attached coincides with the protruding direction of the convex part 131. Therefore, when the reflecting plate 113 is attached to the base 111, the amount by which the base 111 is pushed down by the convex 131 can be further reduced.

  In addition, since a plurality of the convex portions 131 are provided, the stability when the reflecting plate 113 is attached to the base portion 111 is improved. Accordingly, it is possible to reduce the deformation of the shaft portions 12a and 12b due to the inclination of the base portion 111.

  In addition, since the plurality of convex portions 131 are provided at positions where the center of the lower surface (second surface) 111b of the base portion 111 is symmetric with respect to the origin, the stability when the reflector 113 is attached to the base portion 111 is further improved. .

  Moreover, since the length of the some convex part 131 in the thickness direction (up-down direction) of the base 111 is equal, the stability at the time of attaching the reflecting plate 113 to the base 111 improves further.

  In addition, since the length of the convex portion 131 in the thickness direction (vertical direction) of the base portion 111 is equal to or greater than the maximum length of the permanent magnet 21A in the vertical direction, the base portion 111 is attached when the reflector 113 is attached to the base portion 111. Colliding with the permanent magnet 21A can be reduced. Therefore, when the base part 111 collides with the permanent magnet 21A, it is possible to reduce the frame part 13 to which the permanent magnet 21A is fixed and the shaft parts 14a and 14b from being deformed and damaged.

  Further, since the convex portion 131 is provided at a position away from the permanent magnet 21A, the convex portion 131 collides with the permanent magnet 21A when the movable portion 11 swings around the Y axis (first axis). Can be reduced. Therefore, the swing range of the movable part can be expanded.

  Further, since the SOI substrate 400 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 and 14b, and the support frame portion 16 are formed using the SOI substrate 400. By doing so, these dimensional accuracy can be made excellent, and the optical scanner 1 can be miniaturized.

  In addition, since the base 111, the shaft portions 12a and 12b, the frame body portion 13, the shaft portions 14a and 14b, and the support frame portion 16 are each configured by the first Si layer of the SOI substrate, the shaft portions 12a and 12b are formed. Further, the elasticity of the shaft portions 14a and 14b can be made excellent.

  Further, the convex portion 131 can be easily formed by leaving a part of the handle layer positioned below the base portion 111.

<Embodiment 2>
Next, Embodiment 2 of the present invention will be described.
FIG. 8 is a plan view showing the configuration of the optical scanner according to the second embodiment, FIG. 9 is a cross-sectional view (cross-sectional view along the X axis) showing the configuration of the optical scanner according to the second embodiment, and FIG. It is sectional drawing (sectional drawing along AA) which shows the structure of the optical scanner which concerns on form 2. In the following, for convenience of explanation, the upper side in FIG. 9 is referred to as “upper” and the lower side is referred to as “lower”.

  Hereinafter, the second embodiment will be described focusing on the differences from the first embodiment described above, and the description of the same matters will be omitted. 8 to 10, the same reference numerals are given to the same configurations as those of the first embodiment described above. The optical scanner 1A according to the second embodiment is provided with permanent magnets 21B and 21C instead of the permanent magnet 21A, and with permanent magnet fixing parts 17A, 17B, 17C, and 17D (the permanent magnet fixing part 17D is not shown). The optical scanner 1 is the same as the optical scanner 1 of the first embodiment except that the number of the convex portions 131C is one.

  In the second embodiment, only one convex portion 131 </ b> C is provided at the center of the lower surface (second surface) of the base portion 111. Here, when only one convex portion 131 </ b> C is provided at a position away from the center of the lower surface (second surface) of the base portion 111, the base portion 111 is inclined when the reflector 113 is attached to the base portion 111. In the case of the second embodiment, since the convex portion 131C is provided at the center of the lower surface (second surface) of the base 111, the stability when the reflector 113 is attached to the base 111 is improved. Accordingly, it is possible to reduce the deformation of the shaft portions 12a and 12b due to the inclination of the base portion 111.

  A plurality of permanent magnets may be provided. As a result, the driving force for driving the first vibration system and the second vibration system (that is, swinging the movable portion 11 about the X axis and the Y axis) is improved as compared with the case where there is one permanent magnet. be able to. In the second embodiment, two permanent magnets 21B and 21C are provided. Further, the permanent magnets 21B and 21C are installed at positions away from the center of the base 111 in plan view so as not to interfere with the convex 131C.

  The permanent magnets 21B and 21C are respectively magnetized in a direction inclined with respect to the X axis and the Y axis in plan view. The permanent magnets 21B and 21C each have a longitudinal shape (bar shape) extending in a direction inclined with respect to the X axis and the Y axis. The permanent magnets 21B and 21C are each magnetized in the longitudinal direction. That is, each of the permanent magnets 21B and 21C is magnetized so that one end is an S pole and the other end is an N pole. In addition, the permanent magnets 21B and 21C are provided so as to be symmetric (point symmetric) about the intersection of the X axis and the Y axis in plan view.

  In addition, permanent magnet fixing portions 17A, 17B, 17C, and 17D are provided on the lower surface of the frame body portion 13. Furthermore, the permanent magnets 21B and 21C are provided in the permanent magnet fixing portions 17A, 17B, 17C, and 17D. Thus, interference (collision) between the permanent magnets 21B and 21C and the movable part can be prevented without providing the concave portions as in the first embodiment in the permanent magnets 21B and 21C.

  The permanent magnet fixing portions 17A, 17B, 17C, and 17D can be formed integrally with the frame body portion 13 by being formed of, for example, the box layer 400b and the handle layer 400c of the SOI substrate 400.

  As described above, according to the optical scanner 1A according to the second embodiment, in addition to the effects of the first embodiment, the following effects can be obtained. That is, the stability at the time of attaching the reflecting plate 113 to the base 111 can be improved with only one convex portion 131C.

  In addition, the driving force for driving the first vibration system and the second vibration system (that is, swinging the movable portion 11 around the X axis and the Y axis) is improved as compared with the case where there is one permanent magnet. Can do. Further, since the permanent magnet fixing portions 17A, 17B, 17C, and 17D are integrally formed with the frame body portion 13, the permanent magnet fixing portions 17A, 17B, 17C, and 17D are accurately formed at desired positions on the frame body portion 13. be able to.

<Embodiment of Image Display Device>
FIG. 11 is a schematic diagram illustrating the configuration of the image display apparatus. 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 uses light emitted from the light source device 91 (red light source device 911, blue light source device 912, green light source device 913) on the basis of image information from a host computer (not shown), 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 two-dimensional scanning, the light reflected by the reflecting surface 114 due to the rotation of the movable 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 reflecting surface 114 due to the rotation of the movable 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. 11, 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 light two-dimensionally scanned by the optical scanner 1 may be directly emitted to the screen S.

Hereinafter, application examples of the image display device will be described.
<Application Example 1 of Image Display Device>
FIG. 12 is a perspective view illustrating an application example 1 of the image display device. As shown in FIG. 12, 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. 13 is a perspective view illustrating an application example 2 of the image display device. As shown in FIG. 13, 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 the dashboard of an automobile so as to constitute the 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. 14 is a perspective view illustrating an application example 3 of the image display device. As shown in FIG. 14, 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, information from the image display device 9 can be used by adding information from the real world. Note that the head-mounted display 300 may be provided with two image display devices 9 so that images that are visible with both eyes may be displayed on the two display units 320.

  While the optical device and the image display apparatus of the present invention have been described based on the illustrated embodiments, the present invention is not limited to this. For example, in the optical device and the image display apparatus of the present invention, the configuration of each part can be replaced with an arbitrary configuration having a similar function, and other arbitrary configurations can be added.

  Moreover, the convex part 131 should just have the part which protrudes below rather than the lower surface (2nd surface) of the base 111, and the number, a dimension, arrangement | positioning, etc. of a convex part are not specifically limited. For example, it may be provided obliquely downward or may have a branched portion.

  In the first and second embodiments described above, the reflecting plate 113 has been described as an example of a circular shape in plan view. However, the shape of the reflecting plate 113 in plan view is not limited to this, for example, It may be a polygon such as an ellipse or a rectangle.

  Moreover, although Embodiment 1 and 2 mentioned above demonstrated as an example the case where two axial parts (one pair) were provided, it is not limited to this, For example, four axial parts (two pairs) or more It may be provided. In addition, the shapes of the shaft portions 12a and 12b and the shaft portions 14a and 14b are not limited to those shown in the first and second embodiments, for example, a bent or curved portion or a branched portion at at least one place in the middle You may have.

  In the first and second embodiments described above, the case where the reflection plate covers the entire shaft portion in a plan view has been described as an example. If the optical device is covered, the size of the optical device as described above, the area of the reflector is increased, the deflection of the reflector is prevented, the stray light is prevented by the end on the base side of the shaft, etc. There is an effect.

  In the first and second embodiments, the case where the reflector 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 reflector and the spacer are separated from different substrates. It may be formed. The spacer between the reflector and the base may be a solder ball. In this case, for example, a metal film may be formed on each of the reflecting plate and the spacer-side surface of the base, and these metal films may be bonded to each other via a solder ball.

  In addition, the constituent material and the forming method of the base 111, the shaft portions 12a and 12b, the frame body portion 13, the shaft portions 14a and 14b, the support frame portion 16, the support portion 15, and the convex portion 131 are examples, and the present invention It is not limited to this.

  In the first and second embodiments described above, the case where the optical device 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 optical device of the present invention includes, for example, an optical switch and an optical attenuator. The present invention can also be applied to other optical devices.

  DESCRIPTION OF SYMBOLS 1 ... Optical scanner 1A ... Optical scanner 4 ... Voltage application means 7 ... Control part 9 ... Image display apparatus 11 ... Movable part 12a, 12b ... Shaft part (1st shaft part) 13 ... Frame body part 14, 14b ... Shaft part (Second shaft portion) 15 ... support portion 16 ... support frame portion 17A, 17B, 17C ... permanent magnet fixing portion 21A, 21B, 21C ... permanent magnet 31 ... coil 32 ... magnetic core 41 ... first voltage generating portion 42 ... Second voltage generator 43 ... Voltage superimposing unit 43a ... Adder 91 ... Light source device 92A, 92B, 92C ... Dichroic mirror 93 ... Fixed mirror 100 ... Portable image display device 110 ... Casing 111 ... Base 112 ... Spacer 113 ... Reflection Plate 114 ... Reflecting surface 115 ... Hard layer 120 ... Display 130 ... Keypad 131A, 131B, 131C ... Projection 14 DESCRIPTION OF SYMBOLS 0 ... Audio port 150 ... Control button 160 ... Card slot 170 ... Port 200 ... Head up display system 210 ... Head up display 220 ... Windshield 221a ... Concave part 221b ... Concave part 300 ... Head mounted display 310 ... Glasses 320 ... Display part 400 ... SOI substrate 400a ... first Si layer (device layer) 400b ... SiO2 layer (box layer) 400c ... second Si layer (handle layer) 500 ... oxide film 501 ... oxide film mask 600 ... resist 601 ... etching mask 700 ... Resist 701 ... Etching mask 800 ... Base 911 ... Red light source device 912 ... Blue light source device 913 ... Green light source device S ... Screen T1 ... Period T2 ... Period V1 ... First voltage V ... the second voltage

Claims (11)

A movable part having a base and a reflector having a reflective surface that reflects light and is provided via a spacer provided on the first surface of the base;
A shaft portion that supports the movable portion in a swingable manner around the first axis;
A frame portion swingable around a second axis intersecting the first axis;
A permanent magnet provided in the frame body part,
The base portion and the frame body portion are connected by the shaft portion,
An optical device, wherein a convex portion is provided on a second surface opposite to the first surface of the base portion. The base portion, the shaft portion, and the frame body portion are formed using a device layer of a silicon on insulator (SOI) substrate,
The optical device according to claim 1, wherein the convex portion is formed using a handle layer of the SOI substrate.   The optical device according to claim 1, wherein the convex portion is provided in a thickness direction of the base portion. The permanent magnet is provided so as to straddle the base,
4. The optical device according to claim 1, wherein a length of the convex portion in the thickness direction of the base portion is equal to or greater than a maximum length of the permanent magnet in the thickness direction of the base portion.   The optical device according to any one of claims 1 to 4, wherein the convex portion is provided at a position away from the permanent magnet. A plurality of the convex portions are provided on the second surface,
The optical device according to claim 1, wherein the lengths of the convex portions in the thickness direction of the base portion are equal. Coils,
Voltage applying means for applying a voltage to the coil,
The permanent magnet is disposed in a direction inclined with respect to the first axis and the second axis in plan view,
The voltage applying means includes a first voltage having a first frequency that causes the movable portion to swing around the first axis, and a second frequency that causes the frame body portion to swing around the second axis. The optical device according to claim 1, wherein a voltage superposed with a voltage of 2 is applied to the coil. A movable part having a base and a reflector having a reflective surface that reflects light and is provided via a spacer provided on the first surface of the base;
A shaft portion that supports the movable portion in a swingable manner around the first axis;
A frame portion swingable around a second axis intersecting the first axis;
A permanent magnet provided in the frame body part,
The base portion and the frame body portion are connected by the shaft portion,
An optical device in which a convex portion is provided on a second surface opposite to the first surface of the base;
An image display apparatus comprising: a light source that emits light to the optical device. Forming a base portion, a frame body portion, and a first shaft portion connecting the base portion and the frame body portion using a device layer of a silicon on insulator (SOI) substrate;
Using the handle layer of the SOI substrate to form a protrusion on the base;
Fixing a permanent magnet to the frame body part;
And a step of fixing a reflecting plate having a reflecting surface for reflecting light to the surface on the device layer side of the base through a spacer provided on the reflecting plate. . Forming a base portion, a frame body portion, and a first shaft portion connecting the base portion and the frame body portion using a device layer of a silicon on insulator (SOI) substrate;
Using the handle layer of the SOI substrate to form a protrusion on the base;
Fixing a permanent magnet to the frame body part;
Fixing a spacer on the surface of the base on the device layer side;
And a step of fixing a reflecting plate having a reflecting surface for reflecting light to a surface on the opposite side of the surface fixed to the base of the spacer.   In the step of forming the convex portion, the convex portion is formed such that the length of the convex portion in the thickness direction of the base portion is equal to or greater than the maximum length of the permanent magnet in the thickness direction of the base portion. Item 11. A method for producing an optical device according to Item 9 or 10.

Images