JP2020013048A - Optical scanner - Google Patents

Abstract

To provide an optical scanner capable of driving a driven part by suppressing power consumption.SOLUTION: An optical scanner includes: a reflection plate 101; an inner base 102; an outer base 103 disposed outside the inner base 102; an inner elastic part 104 that mutually connects the inner base 102 and the reflection plate 101 and rotatably supports the reflection plate 101 around an inner rotating shaft 104a; an outer elastic part 105 that mutually connects the outer base 103 and the inner base 102 and rotatably supports them around an outer rotating shaft 105a; an outer driving part 122 that rotates the inner base 102 around the outer rotating shaft 105a, at a first frequency that is a resonance frequency of an outer vibration system in which the inner base 102 and the outer elastic part 105 are added to the inner vibration system having the reflection plate 101 and the inner elastic part 104; and an inner driving part 121 that rotates the reflection plate 101 around the inner rotating shaft 104a, at a second frequency lower than the first frequency.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an optical scanning device that scans a scanning target area with incident light from a light source.

  2. Description of the Related Art Conventionally, an optical scanning device that scans a scanning target area with incident light from a light source is known (for example, see Patent Document 1). The optical scanning device described in Patent Literature 1 scans a scanning target area by changing a reflection direction of incident light by driving a driven portion having a reflection surface that reflects the incident light.

  Here, the optical scanning device described in Patent Document 1 is a device that drives a driven portion around two different rotation axes. In order to enable such a two-axis drive, the driven part is rotatably connected to the inner base via an inner elastic part via an inner elastic part, and the inner base is connected to the outer base via an outer elastic part. And is connected so as to be rotatable around the outer rotation axis. Then, the driven portion is driven by applying a magnetic force generated by applying a current to the coil by the magnetic actuator to the magnet attached to the inner base.

Japanese Patent No. 5045611

  Incidentally, in recent years, suppression of power consumption has been demanded also in the field of the above-described optical scanning device. In response to such a demand, for example, it is conceivable to reduce the current flowing through the coil in the magnetic actuator to reduce the power consumption by reducing the weight of the movable portion including the driven portion, which is moved by the magnetic actuator. However, it is difficult to further reduce the weight of each component of the optical scanning device, which is being miniaturized, and at present, no effective proposal has been made for suppressing power consumption.

  Therefore, an object of the present invention is to provide an optical scanning device capable of driving a driven portion while suppressing power consumption, for example.

  In order to solve the above-described problems and achieve the object, an optical scanning device according to the present invention according to claim 1, wherein a driven portion having a reflection surface that reflects incident light, an inner base, and an outer side of the inner base. An outer base, an inner elastic portion that connects the inner base and the driven portion to each other, and supports the driven portion rotatably around an inner rotation axis; and the outer base and the inner side. An inner elastic system that connects the bases to each other and supports the inner base so as to be rotatable about an outer rotational axis different from the inner rotational axis; and an inner vibration system having the driven portion and the inner elastic portion. An outer driving unit configured to rotate the inner base around the outer rotation axis at a first frequency that is a resonance frequency of an outer vibration system obtained by adding the inner base and the outer elastic unit to the outer driving unit; Driven at a low second frequency The characterized in that it comprises a inner driving unit for rotating said inner rotary shaft direction.

FIG. 2 is a schematic diagram illustrating an optical scanning device according to a first embodiment. FIG. 2 is a perspective view showing in detail a driving device schematically shown in FIG. 1. FIG. 2 is a plan view of the structure including the reflection plate, the inner base, the outer base, the inner elastic portion, the outer elastic portion, and the magnetic element, as viewed from each of a reflection surface and an opposite surface of the reflection plate. FIG. It is a figure which shows a mode that a reflection board is rotated about an inner side rotation axis by an inner side drive part, and an inner base is rotated by an outer side drive part together with a reflection plate around an outer side rotation axis. It is the perspective view which looked at the drive in a 2nd example from each side of a reflective surface and an opposite surface of a reflective plate. FIG. 5 is a plan view of a structure including the reflector, the inner base, the outer base, the inner elastic portion, the outer elastic portion, and the magnetic element, as viewed from each of a reflection surface and an opposite surface of the reflection plate. FIG. FIG. 5 is a diagram illustrating a state in which the reflection plate is rotated around an inner rotation axis by an inner driving unit and the inner base is rotated together with the reflection plate around an outer rotation axis by an outer driving unit in the driving device illustrated in FIG. 5. It is. It is the perspective view which looked at the drive in a 3rd example from each side of a reflective side and an opposite side of a reflective plate. FIG. 8 is a plan view of the structure including the reflector, the inner base, the outer base, the inner elastic portion, the outer elastic portion, and the magnetic element, as viewed from each side of the reflective surface and the opposite surface of the reflective plate. FIG. FIG. 8 is a diagram illustrating a state in which the reflection plate is rotated around the inner rotation axis by the inner driving unit and the inner base is rotated together with the reflection plate around the outer rotation axis by the outer driving unit in the driving device illustrated in FIG. 8. It is.

  Hereinafter, embodiments of the present invention will be described. An optical scanning device according to an embodiment of the present invention includes a driven section, an inner base, an outer base, an inner elastic section, an outer elastic section, an outer driving section, and an inner driving section. The driven part has a reflection surface that reflects the incident light. The outer base is located outside the inner base. The inner elastic portion connects the inner base and the driven portion to each other, and supports the driven portion rotatably around the inner rotation axis. The outer elastic portion connects the outer base and the inner base to each other, and supports the inner base so as to be rotatable around an outer rotation axis different from the inner rotation axis. The outer driving section rotates the inner base around the outer rotation axis at a first frequency which is a resonance frequency of an outer vibration system obtained by adding an inner base and an outer elastic section to an inner vibration system having a driven section and an inner elastic section. Move. The inner drive unit rotates the driven unit around the inner rotation axis at a second frequency lower than the first frequency.

  In the optical scanning device according to the present embodiment, the outer driving unit controls the inner base, that is, the outer vibration system having a relatively large moment of inertia among the inner vibration system and the outer vibration system at the resonance frequency of the outer vibration system. Drive. Thus, the resonance of the outer vibration system itself is used for driving the outer vibration system, so that even if the outer drive unit consumes power as driving energy, the power consumption can be suppressed. In addition, since the inner drive unit drives the inner vibration system having a relatively small moment of inertia, it is possible to suppress power consumption by nature. As described above, according to the optical scanning device of the present embodiment, it is possible to drive the driven portion while suppressing power consumption.

  Here, in the present embodiment, the inner driving unit rotates the driven unit at a frequency lower than the resonance frequency of the inner vibration system as the second frequency.

  According to this optical scanning device, since the inner driving unit does not generate resonance in the inner vibration system, for example, by controlling the amount of power consumed as driving energy, the rotation angle of the driven unit can be increased. Can be controlled precisely.

  In the present embodiment, the resonance frequency of the inner vibration system is lower than the resonance frequency of the outer vibration system.

  In general, the lower the resonance frequency of an object, the more easily the stress generated when the object vibrates is dispersed. According to the optical scanning device of the present embodiment, since the resonance frequency of the inner vibration system is lower than the resonance frequency of the outer vibration system, the stress generated in each vibration system during vibration is larger in the inner vibration system than in the outer vibration system. It becomes easy to disperse. Accordingly, the occurrence of distortion of the driven portion during rotation is suppressed, so that the optical performance of the optical scanning device can be improved.

  Further, the optical scanning device of the present embodiment may have the following configuration. That is, the inner drive unit may have the first magnetic element and the first magnetic actuator, and the outer drive unit may have the second magnetic element and the second magnetic actuator. The first magnetic element is mounted on a surface of the driven portion opposite to the reflection surface. The first magnetic actuator magnetically acts on the first magnetic element to rotate the driven portion about the inner rotation axis. The second magnetic element is attached to the inner base. The second magnetic actuator magnetically acts on the second magnetic element to rotate the inner base about the outer rotation axis.

  According to this optical scanning device, by using a simple magnetic structure of the first magnetic element attached to the driven portion and the first magnetic actuator magnetically acting on the first magnetic element, the driven portion can be rotated inside the rotating shaft. It can be easily rotated around. Further, by using the simple magnetic structure of the second magnetic element attached to the inner base and the second magnetic actuator that magnetically acts on the second magnetic element, the rotation of the inner base about the outer rotation axis can be easily performed. Can do it.

  Hereinafter, an embodiment for solving the problem of rotating a driven part at a wide angle while suppressing distortion of the driven part will be specifically described with reference to the drawings. First, a first embodiment will be described.

  FIG. 1 is a schematic diagram showing an optical scanning device according to the first embodiment.

  The optical scanning device 1 shown in FIG. 1 includes a light source 11, a light detector 12, a beam splitter 13, a light source lens 14, a detector lens 15, a shared lens 16, and a driving device 100. The optical scanning device 1 scans a scanning target area with incident light L11 from a light source 11, and scans the scanning target area based on a time until return light L12 from the scanning target area is detected by the optical detector 12. This device measures the distance to an existing object. As an example of the use form, for example, a form of detecting a surrounding situation while the vehicle is running while being mounted on a vehicle is cited.

  In the optical scanning device 1, the incident light L11 from the light source 11 passes through the light source lens 14, passes through the beam splitter 13, is reflected by the reflection plate 101 mounted as a driven unit in the driving device 100, and travels to the scanning target area. Is irradiated. The driving device 100 performs scanning by rotating the reflection plate 101 to change the reflection direction of the incident light L11 from the light source 11. A magnetic element 106 that receives magnetic forces from the first magnetic actuator 107 and the second magnetic actuator 108 is disposed on a surface 101 b of the reflecting plate 101 opposite to the reflecting surface 101 a. In the driving device 100, a reflection area is formed on a reflection surface 101 a of the reflection plate 101 opposite to the magnetic element 106. The magnetic force generated by each of the first magnetic actuator 107 and the second magnetic actuator 108 is controlled by the first control unit 109 and the second control unit 110. By this control, the rotation of the reflection plate 101 is controlled.

  The return light L12 from the scanning target area passes through the common lens 16 and is reflected by the reflection plate 101 of the driving device 100, passes through the beam splitter 13 and the detector lens 15, and travels toward the optical detector 12. Then, in a control device (not shown), based on the time from when the incident light L11 is emitted from the light source 11 to when the return light L12 is detected by the light detector 12, the distance to the object existing in the scanning target area is determined. Is calculated.

  FIG. 2 is a perspective view showing in detail the driving device schematically shown in FIG.

  The driving device 100 includes a reflecting plate 101, an inner base 102, an outer base 103, an inner elastic portion 104, an outer elastic portion 105, a magnetic element 106, a first magnetic actuator 107, a second magnetic actuator 108, a first controller 109, and A second control unit 110 is provided.

  The reflecting plate 101 is a driven body in the driving device 100 as described above, and is formed in a substantially disc shape, and has a reflecting surface 101a formed on one surface by vapor deposition of gold or aluminum. . The magnetic element 106 is arranged on the surface 101b opposite to the reflection surface 101a.

  The inner base 102 is a rectangular frame that extends in the in-plane direction of the reflection plate 101, has a gap with the reflection plate 101, and is arranged so as to surround the outside thereof. The outer base 103 is also a rectangular frame that extends in the in-plane direction of the reflection plate 101, has a gap with the inner base 102, and is arranged so as to surround the outside.

  The inner elastic portion 104 is provided in a gap between the reflection plate 101 and the inner base 102. The inner elastic portion 104 supports the reflecting plate 101 from both sides in the in-plane direction of the reflecting plate 101, and a pair is provided so as to define an inner rotating shaft 104a extending in the in-plane direction of the reflecting plate 101. . The reflecting plate 101 is rotatably supported by the pair of inner elastic portions 104 and connected to the inner base 102. The pair of inner elastic portions 104 includes a torsion bar that is twisted about the inner rotating shaft 104a. Has become.

  The outer elastic portion 105 is provided in a gap between the inner base 102 and the outer base 103. The outer elastic portion 105 supports the inner base 102 from both sides in the in-plane direction of the reflection plate 101, and extends in the in-plane direction of the reflection plate 101, and is an outer rotation axis orthogonal to the inner rotation axis 104a. A pair is provided to define 105a. The inner base 102 is rotatably supported by the pair of outer elastic portions 105 and connected to the outer base 103. The pair of outer elastic portions 105 includes a torsion bar that is twisted about an outer rotating shaft 105a. Has become.

  In this embodiment, the reflection plate 101, the inner base 102, the outer base 103, the inner elastic portion 104, and the outer elastic portion 105 are integrally formed on a silicon substrate.

  The magnetic element 106 is a permanent magnet in the shape of a square plate fixed substantially at the center of the opposite surface 101b of the reflecting plate 101 with respect to the reflecting surface 101a. The magnetic element 106 is magnetized so as to generate a magnetic force in the thickness direction.

  The first magnetic actuator 107 magnetically acts on the magnetic element 106 to rotate the reflection plate 101 in a first rotation direction D11 around the inner rotation shaft 104a. The first magnetic actuator 107 includes a C-shaped yoke 107a and coils 107b formed on two arms of the yoke 107a. In the first magnetic actuator 107, the C-shaped surface of the yoke 107a is a surface orthogonal to the reflection plate 101 and the inner rotation shaft 104a, and the magnetic element 106 is located between the ends of the arms of the yoke 107a. Placed in When a current flows through the coil 107b of the first magnetic actuator 107 arranged in this way, the magnetic force of the magnetic element 106 and the magnetic force in a direction orthogonal to the inner rotation shaft 104a are generated between the ends of the arms of the yoke 107a. appear. The repulsion and attraction between the magnetic force generated in this way and the magnetic force of the magnetic element 106 causes the reflection plate 101 to rotate in the first rotation direction D11.

  The second magnetic actuator 108 magnetically acts on the magnetic element 106 to rotate the inner base 102 together with the reflector 101 in the second rotating direction D12 around the outer rotating shaft 105a. The second magnetic actuator 108 includes a C-shaped yoke 108a and coils 108b formed on each of two arms of the yoke 108a. The second magnetic actuator 108 is configured such that the C-shaped surface of the yoke 108a is a surface orthogonal to the reflector 101 and the outer rotation shaft 105a, and the magnetic element 106 is located between the ends of the arms of the yoke 108a. Placed in When a current flows through the coil 108b of the second magnetic actuator 108 arranged in this manner, the magnetic force of the magnetic element 106 and the magnetic force in a direction orthogonal to the outer rotation shaft 105a are generated between the ends of the arms of the yoke 108a. appear. The repulsion and attraction between the magnetic force thus generated and the magnetic force of the magnetic element 106 causes the inner base 102 to rotate together with the reflection plate 101 in the second rotation direction D12.

  The first control unit 109 supplies an AC current to the coil 107b of the first magnetic actuator 107, and controls the rotation of the reflection plate 101 about the inner rotation axis 104a by controlling the AC current. Further, the second control unit 110 supplies an AC current to the coil 108b of the second magnetic actuator 108 and controls the AC current so that the outer rotating shaft of the reflecting plate 101 that rotates together with the inner base 102. It controls the rotation around 105a.

  In the present embodiment, the magnetic element 106, the first magnetic actuator 107, and the first control unit 109 constitute an inner drive unit 121 that rotates the reflection plate 101 around the inner rotation shaft 104a. The magnetic element 106, the second magnetic actuator 108, and the second control unit 110 constitute an outer driving unit 122 that rotates the inner base 102 together with the reflection plate 101 around the outer rotating shaft 105a.

  As described above, the driving device 100 of this embodiment is a two-axis driving device that rotates the reflection plate 101 around the inner rotation shaft 104a and the outer rotation shaft 105a. Thus, the optical scanning device 1 shown in FIG. 1 is a device capable of two-dimensional scanning for scanning the operation target area in two directions orthogonal to each other.

  FIG. 3 illustrates a structure including a reflector, an inner base, an outer base, an inner elastic portion, an outer elastic portion, and a magnetic element illustrated in FIG. 2 on each side of a reflective surface and an opposite surface of the reflective plate. It is the top view seen from.

  The structure 130 shown in FIG. 3 includes an inner vibration system 131 that rotates around the inner rotation shaft 104a and an outer vibration system 132 that rotates around the outer rotation shaft 105a. The inner vibration system 131 includes the reflector 101, the pair of inner elastic portions 104, and the magnetic element 106. The outer vibration system 132 is obtained by adding the inner base 102 and the outer elastic portion 105 to the inner vibration system 131, and includes a reflector 101, an inner base 102, a pair of inner elastic portions 104, a pair of outer elastic portions 105, and a magnetic member. It is composed of an element 106.

  Here, in the present embodiment, the resonance frequency f11 of the inner vibration system 131 is lower than the resonance frequency f12 of the outer vibration system 132.

  The resonance frequency f11 of the inner vibration system 131 is determined by the moment of inertia about the inner rotation shaft 104a of the inner vibration system 131 and the spring constant of the inner elastic portion 104. On the other hand, the resonance frequency f12 of the outer vibration system 132 is determined by the moment of inertia of the outer vibration system 132 around the outer rotation shaft 105a and the spring constant of the outer elastic portion 105. The resonance frequency of each vibration system decreases as the moment of inertia of each vibration system increases and the spring constant of each elastic portion decreases.

  The inner vibration system 131 having fewer components than the outer vibration system 132 tends to have a smaller moment of inertia than the outer vibration system 132 and a higher resonance frequency f11. On the other hand, in the present embodiment, the spring constant of the inner elastic portion 104 is smaller than the spring constant of the outer elastic portion 105 so as to compensate for the small moment of inertia. Due to the small spring constant, the resonance frequency f11 of the inner vibration system 131 is set lower than the resonance frequency f12 of the outer vibration system 132. In the present embodiment, such a small spring constant of the inner elastic portion 104 is realized by the inner elastic portion 104 being formed thinner than the outer elastic portion 105 as shown in FIG. ing.

  The structure 130 is provided with a reinforcing structure 133 for the purpose of reinforcing the strength, except for the inner elastic portion 104 and the outer elastic portion 105 which function as torsion bars. The reinforcing structure 133 is provided on each of the opposite surface 101b of the reflection plate 101, the surface of the inner base 102 on the same side as the opposite surface 101b, and the surface of the outer base 103 on the same side as the opposite surface 101b. The reinforcing structure 133 is a silicon layer formed on the substrate layer 134 formed of silicon via the oxide film 135. The inner elastic portion 104 and the outer elastic portion 105 where the reinforcing structure 133 is not provided have a single-layer structure including only the silicon substrate layer 134.

  Here, in the present embodiment, the reinforcing structure 133 of the outer base 103 is provided with a wide gap as follows between the outer elastic portion 105 and the reinforcing structure 133. That is, the gap between the reinforcing structure 133 of the outer base 103 and the outer elastic portion 105 is between the reinforcing structure 133 of the reflector 101 and the inner elastic portion 104, and between the reinforcing structure 133 of the inner base 102 and the inner elastic portion 104. It is wider than between the outer elastic portion 105.

  The reinforcing structure 133 of the reflector 101 and the inner base 102 is provided over substantially the entire area of the reflector 101 and the inner base 102. For this reason, the reinforcing structure 133 of the reflecting plate 101 reaches the connecting portion between the reflecting plate 101 and the inner elastic portion 104, and the reinforcing structure 133 of the inner base 102 includes the inner base 102, the inner elastic portion 104, and the outer elastic portion. 105 to the connection with each. On the other hand, the reinforcing structure 133 of the outer base 103 is provided such that a trapezoidal area is opened around a connection portion between the outer base 103 and the outer elastic portion 105. The area opened in this manner has a higher spring constant than the inner elastic portion 104, and disperses the internal stress of the outer elastic portion 105, which tends to be high when rotating, to the outer base 103 side to reduce the stress. The stress relaxation region 136 is formed. Note that the reinforcing structure 133 of the reflector 101 may be provided with a stress relief region by providing a gap between the connecting portion between the reflector 101 and the inner elastic portion 104. By providing a gap at a connection portion between the inner base 102 and each of the inner elastic portion 104 and the outer elastic portion 105, a stress relaxation region may be provided.

  Further, in the present embodiment, the thickness of the connecting portion between the outer elastic portion 105 and the outer base 103 is smaller than the thickness of the connecting portion with the inner base 102. Specifically, the outer elastic portion 105 is formed in a tapered shape whose width gradually decreases from the inner base 102 to the outer base 103. Such a shape of the outer elastic portion 105 also plays a role of dispersing the internal stress of the outer elastic portion 105 during rotation to the outer base 103 side.

  The reflection plate 101 of the structure 130 described above is rotated in the first rotation direction D11 around the inner rotation shaft 104a by the inner driving unit 121 shown in FIG. Further, the inner base 102 is rotated together with the reflection plate 101 in the second rotation direction D12 around the outer rotation shaft 105a by the outer drive unit 122.

  FIG. 4 is a diagram illustrating a state in which the reflection plate is rotated around the inner rotation axis by the inner driving unit, and the inner base is rotated together with the reflection plate about the outer rotation axis by the outer driving unit. In FIG. 4, the structure 130 shown in FIG. 3 is illustrated in two cross sections, a cross section orthogonal to the inner rotation shaft 104a and a cross section orthogonal to the outer rotation shaft 105a.

  First, as described above, the magnetic element 106 attached to the reflection plate 101 generates a magnetic force F11 in the thickness direction. Then, when the first control unit 109 supplies an AC current to the coil 107b of the first magnetic actuator 107, the magnetic force F11 of the magnetic element 106 and the inner rotating shaft 104a are perpendicular to the ends of the two arms of the yoke 107a. The generated magnetic force F12 is generated. The repulsion and attraction between the magnetic force F12 thus generated and the magnetic force F11 of the magnetic element 106 causes the reflection plate 101 to rotate around the inner rotation shaft 104a in the first rotation direction D11. In FIG. 4, the magnetic force F12 generated by the first magnetic actuator 107 is indicated by a right-pointing arrow in the drawing to make the drawing easier to see. However, in fact, it goes without saying that the direction of the magnetic force F12 is reversed every time the polarity of the AC current flowing through the first control unit 109 changes. Similarly, the first rotation direction D11 is also indicated by an upward arcuate arrow in the figure, but every time the polarity of the AC current is changed and the direction of the magnetic force F12 of the first magnetic actuator 107 is reversed, the first rotation direction D11 is changed. The direction of one rotation direction D11 is also reversed.

  When the second control unit 110 causes an AC current to flow through the coil 108b of the second magnetic actuator 108, the magnetic force F11 of the magnetic element 106 and the direction orthogonal to the outer rotating shaft 105a between the ends of the two arms of the yoke 108a. Magnetic force F13 is generated. The repulsion and attraction between the magnetic force F13 generated in this way and the magnetic force F11 of the magnetic element 106 causes the inner base 102 to rotate around the outer rotation shaft 105a in the second rotation direction D12. At this time, since the inner base 102 is connected to the reflector 101 via the inner elastic portion 104, the inner base 102 rotates together with the reflector 101. In FIG. 4, the magnetic force F13 generated by the second magnetic actuator 108 and the second rotation direction D12 are also indicated by arrows pointing in one direction. However, it goes without saying that the magnetic force F13 and the direction of the second rotation direction D12 are reversed each time the polarity of the AC current flowing by the second control unit 110 changes.

  Here, the outer driving section 122 rotates the inner base 102 together with the reflection plate 101 around the outer rotating shaft 105a at the first frequency f13. The first frequency f13 is the resonance frequency f12 of the outer vibration system 132 having the reflector 101, the inner base 102, the inner elastic portion 104, the outer elastic portion 105, and the magnetic element 106. Specifically, the rotation is performed by the second control unit 110 passing the AC current of the first frequency f13 to the coil 108b of the second magnetic actuator 108. As a result, resonance at the resonance frequency f12 occurs in the outer vibration system 132, and the reflection plate 101 and the inner base 102 are driven to resonate. In the resonance driving, since the vibration of the reflection plate 101 and the inner base 102 becomes a sine wave vibration, a sine wave AC current is adopted as the AC current that the second control unit 110 flows through the coil 108b.

  On the other hand, the inner driving section 121 rotates the reflection plate 101 around the inner rotation shaft 104a at a second frequency f14 lower than the first frequency f13 which is the resonance frequency f12 of the outer vibration system 132. Specifically, the rotation is performed by the first control unit 109 flowing the AC current of the second frequency f14 to the coil 107b of the first magnetic actuator 107.

  At this time, in the present embodiment, the inner drive unit 121 sets the second frequency f14 at a frequency lower than the resonance frequency f11 of the inner vibration system 131 including the reflector 101, the inner elastic part 104, and the magnetic element 106. , The reflecting plate 101 is rotated. As a result, no resonance occurs in the inner vibration system 131, and vibration corresponding to the amplitude change of the AC current flowing through the coil 107b by the first control unit 109 occurs linearly, and the reflection plate 101 is driven linearly. Become. In the linear drive, since the vibration of the reflection plate 101 linearly corresponds to the change in the amplitude of the AC current, the AC current flowing through the coil 107b by the first control unit 109 may be a triangular AC current or a sine wave AC current. An AC current having a desired waveform such as a sawtooth wave AC current is employed.

  In the optical scanning device 1 shown in FIG. 1, the scanning by the incident light L11 when the reflection plate 101 and the inner base 102 are driven to resonate around the outer rotation axis 105a is performed by the rotation of the reflection plate 101 by the resonance driving. Because of its wide range and high rotation speed, it is used for main scanning. On the other hand, the scanning by the incident light L11 when the reflector 101 is linearly driven around the inner rotation axis 104a, and the rotation of the reflector 101 by the linear drive is precisely controlled by the AC current flowing through the first controller 109. It is used as a sub-scan because it is possible.

  According to the driving device 100 and the optical scanning device 1 of the first embodiment described above, the resonance frequency f11 of the inner vibration system 131 is lower than the resonance frequency f12 of the outer vibration system 132. Generally, in a torsional vibration system, the lower the resonance frequency is, the smaller the spring constant of the elastic portion can be. In this embodiment, by setting the resonance frequency f11 of the inner vibration system 131 lower than the resonance frequency f12 of the outer vibration system 132, the spring constant of the inner elastic portion 104 included in the inner vibration system 131 is reduced. As a result, it is possible to suppress the stress acting on the connecting portion between the reflection plate 101 and the inner elastic portion 104. Thus, according to the present embodiment, the reflector 101 can be rotated at a wide angle while suppressing the distortion of the reflector 101.

  Here, in the present embodiment, the spring constant of the inner elastic portion 104 is smaller than the spring constant of the outer elastic portion 105. By providing such a difference in the spring constant, the resonance frequency f11 of the inner vibration system 131 can be easily made lower than the resonance frequency f12 of the outer vibration system 132.

  Further, in this embodiment, the reflection plate 101 is attached to the inner rotation shaft 104a by using a simple magnetic structure of the magnetic element 106 attached to the reflection plate 101 and the first magnetic actuator 107 which magnetically acts on the reflection element 101. It can be easily rotated around.

  Further, in this embodiment, by adding the second magnetic actuator 108 which magnetically acts on the magnetic element 106, the inner base 102 can be easily rotated together with the reflection plate 101 around the outer rotation shaft 105a. .

  Further, in the present embodiment, the reinforcing structure 133 provided on the outer base 103 is provided such that the above-mentioned wide gap is provided between the outer base 103 and the outer elastic portion 105 as a stress relaxation region 136. Thereby, the stress generated when the reflection plate 101 and the inner base 102 rotate can be dispersed and relaxed in the above-described wide stress relaxation region 136.

  Further, in the present embodiment, the thickness of the connecting portion between the outer elastic portion 105 and the outer base 103 is smaller than the thickness of the connecting portion with the inner base 102. Accordingly, a place where the stress increases when the reflection plate 101 or the inner base 102 rotates can be brought closer to the connection portion between the outer base 103 and the outer elastic portion 105 far from the reflection plate 101. Can be further suppressed.

  Further, in the present embodiment, the outer driving unit 122 transmits the inner base 102, that is, the outer vibrating system 132 having a relatively large moment of inertia among the inner vibrating system 131 and the outer vibrating system 132 to the outer vibrating system 132. At the resonance frequency f12. Thereby, the resonance of the outer vibration system 132 itself is used for driving the outer vibration system 132, so that the power consumption of the outer drive unit 122 can be suppressed. In addition, since the inner driving section 121 drives the inner vibration system 131 having a relatively small moment of inertia, power consumption can be suppressed inherently. As described above, according to the present embodiment, it is possible to drive the reflecting plate 101 while suppressing power consumption.

  Further, in the present embodiment, the inner driving section 121 rotates the reflection plate 101 at a frequency lower than the resonance frequency f11 of the inner vibration system 131 as the second frequency. As a result, resonance does not occur in the inner vibration system 131, so that the above-described linear drive is performed, and the magnitude of electric power as drive energy is controlled, thereby precisely controlling the rotation angle of the reflection plate 101. be able to.

  Next, a second embodiment will be described. The second embodiment is different from the first embodiment in the actuator structure for driving the reflection plate 101. On the other hand, the basic structure of the optical scanning device 1 is the same as that of the first embodiment. In the following, the differences between the second embodiment and the first embodiment will be described, and illustration and redundant description of the optical scanning device 1 equivalent to the first embodiment will be omitted.

  FIG. 5 is a perspective view of the driving device according to the second embodiment viewed from each of the reflection surface and the opposite surface of the reflection plate. FIG. 6 illustrates a structure including the reflecting plate, the inner base, the outer base, the inner elastic portion, the outer elastic portion, and the magnetic element illustrated in FIG. 5 on each side of a reflecting surface and an opposite surface of the reflecting plate. It is the top view seen from. In FIGS. 5 and 6, the same components as those shown in FIGS. 2 and 3 are denoted by the same reference numerals as those in FIGS. 2 and 3, and hereinafter, these equivalent components will be referred to. Is omitted.

  The driving device 200 includes a reflection plate 101, an inner base 202, an outer base 103, an inner elastic portion 104, and an outer elastic portion 105, similarly to the driving device 100 of the first embodiment. A reinforcing structure 133 is provided on each of the reflection plate 101, the inner base 202, and the outer base 103. The reinforcing structure 133 of the outer base 103 is provided so that a stress relaxation region 136 is opened in a trapezoidal shape around a connection portion between the outer base 103 and the outer elastic portion 105. A first magnetic element 206 similar to the magnetic element 106 of the first embodiment is fixed to a surface 101b of the reflection plate 101 opposite to the reflection surface 101a.

  Further, two second magnetic elements 207 are fixed to the inner base 202 so as to be line-symmetric with respect to the outer rotating shaft 105a. Two frame portions 202a extending along the outer rotation shaft 105a in the square frame-shaped inner base 202 are provided with a second magnetic element 207 near the intersection of each frame portion 202a and the inner rotation shaft 104a. Are provided. The fixing region 202b may be provided on the protrusion of the inner base 202 as shown in FIG. 5, or may be provided on the reinforcing structure 133 of the inner base 202. Like the first magnetic element 206, the second magnetic element 207 fixed to each fixed region 202b is magnetized so as to generate a magnetic force in the thickness direction. The first magnetic element 206 and the two second magnetic elements 207 are attached so that the directions of the magnetic forces are the same.

  In this embodiment, the structure 230 is configured by the reflector 101, the inner base 202, the outer base 103, the inner elastic part 104, the outer elastic part 105, the first magnetic element 206, and the two second magnetic elements 207. . Then, as shown in FIG. 6, in the structure 230, the reflection plate 101, the inner elastic portion 104, and the first magnetic element 206 in the first rotation direction D11 around the inner rotation shaft 104 a. An inner vibration system 231 in which the reflection plate 101 rotates is configured. Further, the inner base 202, the outer elastic portion 105, and the two second magnetic elements 207 are added to the inner vibration system 231, and the inner base 202 is turned around the outer rotation shaft 105a in the second rotation direction D12. The outer vibrating system 232 that rotates with each other is configured.

  The drive device 200 includes a first magnetic actuator 208 that magnetically acts on the first magnetic element 206 and two second magnetic actuators 209 that magnetically act on the two second magnetic elements 207. Each magnetic actuator includes C-shaped yokes 208a and 209a, and coils 208b and 209b provided at a portion connecting the two arms in the yokes 208a and 209a.

  In addition, the driving device 200 includes a first control unit 210 that supplies an AC current to the coil 208b of the first magnetic actuator 208 and controls the AC current. Furthermore, the second magnetic actuator 209 is provided with a second control unit 211 that supplies an AC current to each coil 209b and controls each AC current.

  In the present embodiment, the first magnetic element 206, the first magnetic actuator 208, and the first control unit 210 constitute an inner drive unit 221 that rotates the reflection plate 101 around the inner rotation shaft 104a. Further, an outer driving unit 222 configured to rotate the inner base 102 together with the reflection plate 101 around the outer rotating shaft 105a by the two second magnetic elements 207, the two second magnetic actuators 209, and the second control unit 211 is configured. Have been.

  FIG. 7 shows the driving device shown in FIG. 5 in which the reflection plate is rotated about the inner rotation axis by the inner driving unit, and the inner base is rotated together with the reflection plate about the outer rotation axis by the outer driving unit. It is a figure showing a situation. In FIG. 7, the structure 230 shown in FIG. 6 is shown in two cross sections, a cross section orthogonal to the inner rotation shaft 104a and a cross section orthogonal to the outer rotation shaft 105a.

  First, the first magnetic element 206 attached to the reflection plate 101 generates a magnetic force F21 in the thickness direction. Then, when the first control unit 210 supplies an AC current to the coil 208b of the first magnetic actuator 208, the magnetic force F21 of the first magnetic element 206 and the inner rotation shaft 104a are placed between the ends of the two arms of the yoke 208a. A magnetic force F22 is generated in a direction orthogonal to. The repulsion and attraction between the magnetic force F22 generated in this way and the magnetic force F21 of the first magnetic element 206 causes the reflection plate 101 to rotate around the inner rotation shaft 104a in the first rotation direction D11. Become. In FIG. 7, the magnetic force F22 generated by the first magnetic actuator 208 is indicated by a rightward arrow in the figure. However, each time the polarity of the AC current flowing by the first control unit 210 changes, the direction of the magnetic force F22 is reversed. Similarly, the first rotation direction D11 is also indicated by an upward arcuate arrow in the figure, but every time the direction of the magnetic force F22 of the first magnetic actuator 208 is reversed, the direction of the first rotation direction D11 is changed. Is also inverted.

  The two second magnetic elements 207 attached to the inner base 202 generate magnetic forces F23 in the same direction in each thickness direction. Then, in the present embodiment, the second control unit 211 passes AC currents having opposite phases to each other through the coils 209 b of the two second magnetic actuators 209. Then, between the ends of the two arms of each yoke 209a, the magnetic force F23 of the second magnetic element 207 and the outer rotating shaft 105a are orthogonal to each other, and the two magnetic actuators 209 are in opposite directions. The following magnetic forces F241 and F242 are generated. By the repulsion and attraction between the two magnetic forces F241 and 242 generated in this way and the magnetic force F23 of the two second magnetic elements 207, the two second magnetic elements 207 are moved upside down. And the power works. As a result, the inner base 202 rotates together with the reflection plate 101 in the second rotation direction D12 around the outer rotation shaft 105a. In FIG. 7, the magnetic forces F241 and 242 generated by the second magnetic actuator 209 and the second rotation direction D12 are indicated by arrows pointing in one direction. However, each time the polarity of the AC current flowing by the second control unit 211 changes, the directions of the magnetic forces F241 and F242 and the second rotation direction D12 are reversed.

  Here, the outer driving section 222 rotates the inner base 202 together with the reflector 101 around the outer rotating shaft 105a at the following first frequency f23. Here, the first frequency f23 refers to an outer vibration system 232 having the reflector 101, the inner base 202, the inner elastic portion 104, the outer elastic portion 105, the first magnetic element 206, and the two second magnetic elements 207. This is the resonance frequency f22. Specifically, the second control unit 211 supplies AC currents having the first frequency f23, which is the resonance frequency f22 of the outer vibration system 232, and phases opposite to each other to the coils 209b of the two second magnetic actuators 209, respectively. Thus, such rotation is performed. As a result, resonance occurs at the resonance frequency f22 in the outer vibration system 232, and the reflection plate 101 and the inner base 202 are driven to resonate. Note that, also in the present embodiment, a sine wave AC current is employed as the AC current that flows through the coil 209b by the second control unit 211 for this resonance drive.

  On the other hand, the inner driving section 221 rotates the reflection plate 101 around the inner rotation shaft 104a at a second frequency f24 lower than the first frequency f23 that is the resonance frequency f22 of the outer vibration system 232. Specifically, the first control section 210 performs such rotation by flowing the AC current of the second frequency f24 to the coil 208b of the first magnetic actuator 208.

  At this time, in the present embodiment, the inner drive unit 221 sets the second frequency f24 to be lower than the resonance frequency f21 of the inner vibration system 231 having the reflector 101, the inner elastic part 104, and the first magnetic element 206. The reflection plate 101 is rotated at the frequency. As a result, no resonance occurs in the inner vibration system 231, and vibration corresponding to the change in the amplitude of the AC current flowing through the coil 208 b by the first control unit 210 occurs linearly, and the reflection plate 101 is driven linearly. Become. In the linear drive, since the vibration of the reflection plate 101 linearly corresponds to the change in the amplitude of the AC current, the AC current having a desired waveform is adopted as the AC current that the first control unit 210 flows through the coil 208b.

  Also in the present embodiment, in the optical scanning device 1 shown in FIG. 1, scanning by the incident light L11 when the reflection plate 101 and the inner base are driven to resonate around the outer rotation shaft 105a is used as main scanning. You. Further, scanning by the incident light L11 when the reflecting plate 101 is linearly driven around the inner rotation shaft 104a is used as sub-scanning.

  The driving device 200 and the optical scanning device 1 of the second embodiment described above can also rotate the reflection plate 101 at a wide angle while suppressing the distortion of the reflection plate 101, as in the first embodiment. It goes without saying that you can do it. Further, according to the present embodiment, it is possible to drive the reflecting plate 101 while suppressing power consumption, similarly to the first embodiment.

  In the present embodiment, two second magnetic elements 207 and two second magnetic actuators 209 attached to the inner base 202 are used for driving the outer vibration system 232 separately from driving the inner vibration system 231. A simple magnetic structure is employed. Thus, the rotation of the inner base 202 about the outer rotation shaft 105a can be easily performed.

  Next, a third embodiment will be described. The third embodiment differs from the first embodiment in the actuator structure for driving the reflection plate 101, similarly to the second embodiment. On the other hand, the basic structure of the optical scanning device 1 is the same as that of the first embodiment. Hereinafter, also in the third embodiment, differences from the first embodiment will be described, and illustration and overlapping description of the optical scanning device 1 equivalent to the first embodiment will be omitted.

  FIG. 8 is a perspective view of the driving device according to the third embodiment as viewed from each of the reflection surface and the opposite surface of the reflection plate. FIG. 9 illustrates a structure including the reflector, the inner base, the outer base, the inner elastic portion, the outer elastic portion, and the magnetic element illustrated in FIG. It is the top view seen from. In FIGS. 8 and 9, components equivalent to those shown in FIGS. 2 and 3 are denoted by the same reference numerals as those in FIGS. 2 and 3. Is omitted.

The driving device 300 includes a reflection plate 101, an inner base 102, an outer base 103, an inner elastic portion 104, and an outer elastic portion 105, similarly to the driving device 100 of the first embodiment. The reflection structure 101, the inner base 102, and the outer base 103 are each provided with a reinforcing structure 133 while forming a stress relaxation region 136 in the outer base 103. A first magnetic element 306 similar to the magnetic element 106 of the first embodiment is fixed to a surface 101b of the reflection plate 101 opposite to the reflection surface 101a.

  Further, a second magnetic element 307 is provided on each of two frame portions 102a extending along the inner rotation shaft 104a in the square frame-shaped inner base 202. The second magnetic element 307 of each frame portion 102a has two element portions 307a arranged so as to be line-symmetric with respect to the outer rotation shaft 105a. Like the first magnetic element 306, each element portion 307a is a permanent magnet that is magnetized so as to generate a magnetic force in the thickness direction. Further, the two element portions 307a are mounted such that the magnetic forces are opposite to each other.

  In this embodiment, the structure 330 is configured by the reflector 101, the inner base 102, the outer base 103, the inner elastic portion 104, the outer elastic portion 105, the first magnetic element 306, and the two second magnetic elements 307. . Then, as shown in FIG. 9, in the structure 330, the reflection plate 101, the inner elastic portion 104, and the first magnetic element 306 in the first rotation direction D11 around the inner rotation axis 104 a. An inner vibration system 331 in which the reflection plate 101 rotates is configured. Further, the inner base 102, the outer elastic portion 105, and the two second magnetic elements 307 are added to the inner vibration system 331, and the inner base 102 is turned around the outer rotation shaft 105a in the second rotation direction D12. The outer vibrating system 332 that rotates with each other is configured.

  The drive device 300 includes a first magnetic actuator 308 that magnetically acts on the first magnetic element 306 and two second magnetic actuators 309 that magnetically act on the two second magnetic elements 307. Each magnetic actuator includes C-shaped yokes 308a, 309a, and coils 308b, 309b provided at portions connecting the two arms in the yokes 308a, 309a.

  In addition, the drive device 300 includes a first control unit 310 that supplies an AC current to the coil 308b of the first magnetic actuator 308 and controls the AC current. Further, a second control unit 311 that controls an AC current while supplying an AC current to the coil 309b of each of the two second magnetic actuators 309 is provided.

  In this embodiment, the first magnetic element 306, the first magnetic actuator 308, and the first control unit 310 form an inner drive unit 321 that rotates the reflection plate 101 around the inner rotation shaft 104a. Further, an outer driving unit 322 configured to rotate the inner base 102 together with the reflection plate 101 around the outer rotating shaft 105a by the two second magnetic elements 307, the two second magnetic actuators 309, and the second control unit 311 is configured. Have been.

  FIG. 10 shows the driving device shown in FIG. 8 in which the reflection plate is rotated about the inner rotation axis by the inner driving unit, and the inner base is rotated together with the reflection plate about the outer rotation axis by the outer driving unit. It is a figure showing a situation. In FIG. 10, the structure 330 shown in FIG. 9 is shown in two cross sections, a cross section orthogonal to the inner rotation shaft 104a and a cross section orthogonal to the outer rotation shaft 105a.

  First, the first magnetic element 306 attached to the reflection plate 101 generates a magnetic force F31 in the thickness direction. When the first control unit 310 supplies an AC current to the coil 308b of the first magnetic actuator 308, the magnetic force F31 of the first magnetic element 306 and the inner rotating shaft 104a are placed between the ends of the two arms of the yoke 308a. A magnetic force F32 is generated in a direction orthogonal to. The repulsion and attraction between the magnetic force F32 thus generated and the magnetic force F31 of the first magnetic element 306 cause the reflection plate 101 to rotate around the inner rotation shaft 104a in the first rotation direction D11. Become. Then, each time the polarity of the AC current flowing by the first control unit 310 changes, the direction of the magnetic force F32 of the first magnetic actuator 308 is inverted, and accordingly, the direction of the first rotation direction D11 is also inverted.

  Two element portions 307a constituting the second magnetic element 307 attached to the inner base 102 generate magnetic forces F331 and F332 in the same direction in each thickness direction. Also, between the two second magnetic elements 307, the direction of the magnetic force in the element portion 307a at the corresponding position is the same.

  Then, in the present embodiment, the second control unit 311 supplies an AC current to the coil 309b of the second magnetic actuator 309 arranged so as to sandwich the two element portions 307a between the ends of the yoke 309a. That is, different polarities appear at each end of the yoke 309a near each of the two element portions 307a. Between the two second magnetic actuators 309 provided for each of the two second magnetic elements 307 each including two element portions 307a, AC currents having the same phase from each other are supplied from the second control unit 311 to each coil 309b. Swept away.

  When such an AC current is applied to the coil 309b of each second magnetic actuator 309, the magnetic force F34 acting collectively on the two element portions 307a between the ends of the two arms of the yoke 309a. Occurs. This magnetic force F34 is orthogonal to the magnetic forces F331 and F332 of each element portion 307a and the outer rotating shaft 105a. The repulsion and attraction between the magnetic force F34 generated in this way and the magnetic forces F331 and F332 of the two element portions 307a exert a force to move the two element portions 307a upside down. As a result, the inner base 102 rotates together with the reflection plate 101 around the outer rotation shaft 105a in the second rotation direction D12. Each time the polarity of the AC current flowing by the second control unit 311 changes, the magnetic force F34 and the direction of the second rotation direction D12 are reversed.

  Here, the outer driving section 322 rotates the inner base 102 together with the reflecting plate 101 around the outer rotating shaft 105a at the following first frequency f33. Here, the first frequency f33 refers to the frequency of the outer vibration system 332 including the reflector 101, the inner base 102, the inner elastic portion 104, the outer elastic portion 105, the first magnetic element 306, and the two second magnetic elements 307. The resonance frequency is f32. Specifically, the second control unit 311 supplies an AC current to each of the coils 309b of the two second magnetic actuators 309 at the first frequency f33, which is the resonance frequency f32 of the outer vibration system 332, so that such a current is generated. Rotation is performed. As a result, resonance occurs at the resonance frequency f32 in the outer vibration system 332, and the reflection plate 101 and the inner base 102 are driven to resonate. Note that, also in the present embodiment, a sine wave AC current is adopted as the AC current that flows through the coil 309b by the second control unit 311 for this resonance drive.

  On the other hand, the inner drive section 321 rotates the reflection plate 101 around the inner rotation shaft 104a at a second frequency f34 lower than the first frequency f33 that is the resonance frequency f32 of the outer vibration system 332. Specifically, the first control section 310 performs such rotation by flowing the AC current of the second frequency f34 to the coil 308b of the first magnetic actuator 308.

  At this time, in the present embodiment, the inner drive unit 321 sets the second frequency f34 to be lower than the resonance frequency f31 of the inner vibrating system 331 including the reflector 101, the inner elastic part 104, and the first magnetic element 306. The reflection plate 101 is rotated at the frequency. As a result, resonance does not occur in the inner vibration system 331, and vibration corresponding to the change in the amplitude of the AC current flowing through the coil 308b by the first control unit 310 linearly occurs, and the reflection plate 101 is driven linearly. Become. In the linear drive, since the vibration of the reflection plate 101 linearly corresponds to the change in the amplitude of the AC current, the AC current having a desired waveform is adopted as the AC current that the first control unit 310 flows through the coil 308b.

  Also in the present embodiment, in the optical scanning device 1 shown in FIG. 1, the scanning by the incident light L11 at the time of the above-described resonance driving is used as the main scanning. In addition, scanning by the incident light L11 during linear driving is used as sub-scanning.

  The driving device 300 and the optical scanning device 1 of the third embodiment described above can also rotate the reflection plate 101 at a wide angle while suppressing the distortion of the reflection plate 101, as in the first embodiment. It goes without saying that you can do it. Further, according to the present embodiment, it is possible to drive the reflecting plate 101 while suppressing power consumption, similarly to the first embodiment.

  In this embodiment, the second magnetic actuator 309 collectively magnetically acts on the two element portions 307a forming the second magnetic element 307. According to this, the number of the second magnetic actuators 309 is reduced as compared with the structure in which the magnetic actuator is provided for each of the two element portions 307a, so that the cost can be reduced by simplifying the device structure.

  It should be noted that the present invention is not limited to the embodiments described above, but includes other configurations and the like that can achieve the object of the present invention, and the following modifications and the like are also included in the present invention.

  For example, in the above-described first to third embodiments, the reflection plate 101 is illustrated as an example of the driven portion. However, the driven portion is not limited to this, and does not matter the specific mode as long as it can be rotated.

  In the first to third embodiments described above, the permanent magnet magnetic element 106 and the first magnetic elements 206 and 306 are illustrated as examples of the first magnetic element. Similarly, as an example of the second magnetic element, a second magnetic element 207 having a permanent magnet and a second magnetic element 307 having two element portions 307a of a permanent magnet are illustrated. However, the first magnetic element and the second magnetic element are not limited to these, and may be, for example, a coil or the like that generates a driving force when a current flows and receives a magnetic field. In this case, the magnetic actuator that moves the coil may be a permanent magnet.

  In the above-described first to third embodiments, the disc-shaped reflecting plate 101, the inner bases 102 and 202 of the square frame, and the outer base 103 of the square frame are illustrated. However, the reflector, the inner base, and the outer base are not limited to these. Each shape of the reflecting plate, the inner base, and the outer base may be a square plate, a circular frame, or the like, and a specific shape may be arbitrarily set.

  In this embodiment, the magnetic element 106, the first magnetic elements 206 and 306, and the second magnetic elements 207 and 307 have been described as being attached to one surface of the reflection plate 101. However, the magnetic element may be mounted on both sides of each mounting position, or an opening may be provided at each mounting position, and the magnetic element may be fitted therein. In this case, magnetic elements appear on both surfaces of the reflection plate 101. When the magnetic element is attached to both sides or is fitted in the opening, the state can be balanced with respect to the rotation axis of the reflector, so that the reflector rotates and tilts to one side when not driven, for example. Nothing.

  In the present embodiment, a rectangular parallelepiped element portion forming the square plate-shaped magnetic element 106, the first magnetic elements 206 and 306, and the rectangular parallelepiped second magnetic element 207 and the second magnetic element 307 is illustrated. . However, the shape and size of these magnetic elements can be arbitrarily set as long as a sufficient force for rotating the reflection plate 101 and the inner bases 102 and 202 can be obtained.

DESCRIPTION OF SYMBOLS 1 Optical scanning device 11 Light source 12 Optical detector 13 Beam splitter 14 Lens for light source 15 Lens for detector 16 Shared lens 100, 200, 300 Driver 101 Reflector 101a Reflection surface 101b Opposite surface 102,202 Inner base 103 Outer base 104 Inner elasticity Part 104a Inner rotating shaft 105 Outer elastic part 105a Outer rotating shaft 106 Magnetic element 107, 208, 308 First magnetic actuator 107a, 108a, 208a, 209a, 308a, 309a Yoke 107b, 108b, 208b, 209b, 308b, 309b Coil 108, 209.309 Second magnetic actuator 109, 210, 310 First control unit 110, 211, 311 Second control unit 121, 221, 321 Inside drive unit 122, 222, 32 Outer drive units 130, 230, 330 Structures 131, 231, 331 Inner vibration system 132, 232, 332 Outer vibration system 133 Reinforcement structure 135 Oxide film 134 Substrate layer 136 Stress relaxation area 202a Frame portion 202b Fixed area 206, 306 First Magnetic element 207, 307 Second magnetic element 307a Element portion D11 First rotation direction D12 Second rotation direction F11, F12, F13, F21, F22, F23, F241, F242, F31, F32, F331, F332, F34 Magnetic force L11 Incident light L12 Return light f12, f22, f32 Resonant frequency f13, f23, f33 First frequency f14, f24, f34 Second frequency

Claims (4)

A driven part having a reflecting surface for reflecting incident light,
An inner base,
An outer base arranged outside the inner base,
An inner elastic portion that connects the inner base and the driven portion to each other and supports the driven portion rotatably around an inner rotation axis;
An outer elastic portion that connects the outer base and the inner base to each other and supports the inner base so as to be rotatable around an outer rotation axis different from the inner rotation axis;
At a first frequency that is a resonance frequency of an outer vibration system obtained by adding the inner base and the outer elastic portion to the inner vibration system having the driven portion and the inner elastic portion, the inner base is rotated around the outer rotation axis. An outer driving unit for rotating,
An inner driving unit configured to rotate the driven unit around the inner rotation axis at a second frequency lower than the first frequency;
An optical scanning device comprising:   2. The optical scanning device according to claim 1, wherein the inner driving unit rotates the driven unit at a frequency lower than a resonance frequency of the inner vibration system as the second frequency. 3.   The optical scanning device according to claim 2, wherein a resonance frequency of the inner vibration system is lower than a resonance frequency of the outer vibration system. A first magnetic element attached to a surface of the driven portion opposite to the reflection surface; and magnetically acting on the first magnetic element to move the driven portion around the inner rotation axis. A first magnetic actuator for rotating,
The outer driving unit includes: a second magnetic element attached to the inner base; and a second magnetic actuator that magnetically acts on the second magnetic element to rotate the inner base about the outer rotation axis. The optical scanning device according to claim 1, further comprising:

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