JP2023107590A - Movable device, distance measurement device, measurement device, robot, electronic apparatus, molding device, image projection device, head-up display, laser head lamp, head-mounted display, object recognition device, vehicle and movable body - Google Patents

Abstract

To provide a movable device which has the excellent detection accuracy of a swing angle.SOLUTION: A movable device comprises: first and second torsion beams having ends connected with each other via a movable part swinging around a first swing shaft; first and second drive beams connected to the other ends of the first and second torsion beams; a first support part supporting each of the first and second drive beams in a cantilever manner; first and second distortion resistances arranged in the first drive beam; third and fourth distortion resistances arranged in the second drive beam; and a detection part outputting angular information around the first swing shaft based on each resistance value of the first to fourth distortion resistances. The first distortion resistance is arranged on the free end side of the first drive beam with respect to the first swing shaft and the third distortion resistance is arranged on the free end side of the second drive beam with respect to the first swing shaft. The second distortion resistance is arranged on any of the fixed and free ends of the first drive beam with respect to the first swing shaft and the fourth distortion resistance is arranged on any of the fixed and free ends of the second drive beam with respect to the first swing shaft. A distance between the first distortion resistance and the first swing shaft is longer than a distance between the second distortion resistance and the first swing shaft. A distance between the third distortion resistance and the first swing shaft is longer than a distance between the fourth distortion resistance and the first swing shaft.SELECTED DRAWING: Figure 4

Description

The present invention relates to mobile devices, distance measuring devices, measuring devices, robots, electronic devices, modeling devices, image projection devices, head-up displays, laser headlamps, head-mounted displays, object recognition devices, vehicles, and moving bodies.

2. Description of the Related Art Conventionally, movable devices using MEMS (Micro Electro Mechanical Systems) devices manufactured by microfabrication of silicon or glass have been known. Movable devices are used in various applications such as in-vehicle laser radar devices, head-up displays, and head-mounted displays.

The movable device includes a pair of torsion beams that are supported on both sides and rockably support the movable portion, and a pair of strain resistors arranged at symmetrical positions about the rocking axis of the movable portion. , which is capable of detecting the swing angle of a movable part using a Wheatstone bridge circuit composed of a pair of strain resistors and a pair of external fixed elements (see, for example, Patent Document 1).

A movable device capable of detecting the swing angle of a movable portion is required to have excellent accuracy in detecting the swing angle of the movable portion.

SUMMARY OF THE INVENTION An object of the present invention is to provide a movable device with excellent accuracy in detecting a swing angle of a movable portion.

A movable device according to an aspect of the present invention includes a movable portion that swings around at least a first swing axis, a first torsion beam that is connected at one end to the movable portion, and the first torsion beam that sandwiches the movable portion. A second torsion beam provided on the opposite side of the beam and having one end connected to the movable part, a first drive beam connected to the other end of the first torsion beam, and a second torsion beam on the other end of the second torsion beam. a connecting second drive beam; a first support that cantilevers each of the first drive beam and the second drive beam; a first strain resistor arranged on the first drive beam; a second strain resistor arranged on the drive beam; a third strain resistor arranged on the second drive beam; a fourth strain resistor arranged on the second drive beam; and a detection unit that outputs rocking angle information of the movable part about the first rocking axis based on each resistance value of the first strain resistor, the first strain resistor being greater than the first rocking axis. The third strain resistor is arranged on the free end side of the first drive beam, the third strain resistor is arranged on the free end side of the second drive beam with respect to the first swing axis, and the second strain resistor is arranged on the free end side of the first drive beam. The fourth strain resistor is disposed on either the fixed end side or the free end side of the first drive beam relative to the first swing axis, and the fourth strain resistor is located closer to the fixed end of the second drive beam than the first swing axis. The distance between the first strain resistor and the first swing axis is greater than the distance between the second strain resistor and the first swing axis. and the distance between the third strain resistor and the first swing axis is longer than the distance between the fourth strain resistor and the first swing axis.

ADVANTAGE OF THE INVENTION According to this invention, the movable apparatus excellent in the precision which detects the rocking angle of a movable part can be provided.

It is a top view which illustrates the movable device which concerns on embodiment. Figure 2 is an end view of the movable device along the second pivot axis of Figure 1; FIG. 2 is an end view of the movable device taken along line III-III of FIG. 1; 4 is a plan view of a detailed configuration example around first to fourth strain resistors according to the first embodiment; FIG. FIG. 4 illustrates a bridge circuit having first through fourth strain resistors; FIG. 11 is a plan view of a detailed configuration example around first to fourth strain resistors according to a first modified example; FIG. 7 is a cross-sectional view along the VII-VII cutting line of FIG. 6; FIG. 10 is a diagram of an example of a bridge circuit including first to fourth strain resistors according to a first modified example; FIG. 11 is a plan view of a detailed configuration example around first to fourth strain resistors according to a second modified example; FIG. 10 is a cross-sectional view along the XX section line of FIG. 9; FIG. 11 is a diagram of an example of a bridge circuit including first to fourth strain resistors according to a second modified example; FIG. 11 is a plan view of a detailed configuration example around first to fourth strain resistors according to a third modified example; FIG. 13 is a cross-sectional view along the XIII-XIII section line of FIG. 12; FIG. 11 is a diagram of an example of a bridge circuit including first to fourth strain resistors according to a third modified example; FIG. 11 is a plan view of a detailed configuration example around first to fourth strain resistors according to a fourth modified example; FIG. 16 is a sectional view along the XVI-XVI section line of FIG. 15; FIG. 11 is a diagram of an example of a bridge circuit including first to fourth strain resistors according to a fourth modified example; FIG. 20 is a plan view of a detailed configuration example around first to fourth strain resistors according to a fifth modification; FIG. 19 is a cross-sectional view along the XIX-XIX cutting line of FIG. 18; FIG. 11 is a diagram of an example of a bridge circuit including first to fourth strain resistors according to a fifth modified example; FIG. 20 is a plan view of a detailed configuration example around first to fourth strain resistors according to a sixth modification; FIG. 22 is a sectional view along the XXII-XXII section line of FIG. 21; FIG. 11 is a diagram of an example of a bridge circuit including first to fourth strain resistors according to a sixth modified example; FIG. 21 is a plan view of a detailed configuration example around first to fourth strain resistors according to a seventh modification; FIG. 25 is a sectional view along the XXV-XXV section line of FIG. 24; FIG. 21 is a diagram of an example of a bridge circuit including first to fourth strain resistors according to a seventh modified example; FIG. 21 is a plan view of a detailed configuration example around first to fourth strain resistors according to an eighth modified example; FIG. 28 is a cross-sectional view along the XXVIII--XXVIII cutting line of FIG. 27; FIG. 20 is a diagram of an example of a bridge circuit including first to fourth strain resistors according to an eighth modified example; 1 is a schematic diagram of an example optical scanning system; FIG. 1 is a hardware configuration diagram of an example of an optical scanning system; FIG. It is a functional block diagram of an example of a control device. 4 is a flowchart of an example of processing related to an optical scanning system; 1 is a schematic diagram of an example of an automobile equipped with a laser radar device; FIG. FIG. 4 is a schematic diagram of another example of a vehicle equipped with a laser radar device; 1 is a schematic diagram of an example of a laser radar device; FIG. 1 is a block diagram of a three-dimensional measuring device; FIG. FIG. 10 is a diagram of an example of a state in which a measurement pattern is projected onto an object; FIG. 2 shows a robot arm with multiple joints of the robot; 1 is a schematic diagram of an example of an image forming apparatus equipped with an optical writing device; FIG. 1 is a schematic diagram of an example of an optical writing device; FIG. 1 is a schematic diagram of an example of a vehicle equipped with a head-up display device; FIG. 1 is a schematic diagram of an example of a head-up display device; FIG. 1 is a schematic diagram of an example laser headlamp; FIG. 1 is an external perspective view of an example of a head mounted display; FIG. It is a figure which illustrates the structure of a head mounted display partially. 1 is a schematic diagram of an example of a packaged mobile device; FIG.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings. In each drawing, the same components are denoted by the same reference numerals, and overlapping descriptions are omitted as appropriate.

In addition, in the following description of the embodiments, rotation, swing, and movement are synonymous. Among the directions indicated by the arrows, the stacking direction of each layer in the piezoelectric driving unit and the like is the Z direction, and the directions orthogonal to the Z direction in a plane perpendicular to the Z direction are the X direction and the Y direction. Planar viewing means viewing an object from the Z direction.

In addition, the direction in which the arrow points in the X direction is indicated as +X direction, the direction opposite to +X direction is indicated as -X direction, the direction in which the arrow points in Y direction is indicated as +Y direction, and the direction opposite to +Y direction is indicated as -Y direction. , the direction in which the arrow points in the Z direction is denoted as the +Z direction, and the direction opposite to the +Z direction is denoted as the -Z direction. However, these do not limit the orientation of the movable device, and the orientation of the movable device during use is arbitrary.

[Embodiment]
<Configuration example of movable device 13>
The configuration of the movable device 13 according to the first embodiment will be described with reference to FIGS. 1 to 3. FIG. FIG. 1 is a plan view illustrating the movable device 13. FIG. FIG. 2 is an end view of mobile device 13 along the second axis of FIG. FIG. 3 is an end view of movable device 13 taken along line III--III in FIG.

As shown in FIG. 1, the movable device 13 includes a movable portion 101, a first torsion beam 111a, a second torsion beam 111b, a first drive beam 110a, a second drive beam 110b, and a first support portion 120. , a first strain resistor 160a, and a second strain resistor 160b. The movable device 13 also includes a third strain resistor 160 c, a fourth strain resistor 160 d, a pair of drive units 130 a and 130 b, a second support unit 140 , an electrode connection unit 150 and a controller 11 .

The movable device 13 can scan the light incident on the movable portion 101 in the X direction and the Y direction by swinging the movable portion 101 about the first swing axis Ey and the second swing axis Ex. It is an optical deflection device. The first swing axis Ey is an axis parallel to the Y-axis, and the second swing axis Ex is an axis parallel to the X-axis substantially perpendicular to the Y-axis.

The movable part 101 has a reflecting surface 14 that reflects incident light. One end of the first torsion beam 111 a is connected to the movable portion 101 . The second torsion beam 111b is provided on the opposite side of the first torsion beam 111a with the movable portion 101 interposed therebetween, and is connected to the movable portion 101 at one end.

The first drive beam 110a is connected to the other end side of the first torsion beam 111a, and the second drive beam 110b is connected to the other end side of the second torsion beam 111b. The first support portion 120 cantilevers the first drive beam 110a and the second drive beam 110b. The first support portion 120 is a rectangular frame-shaped support formed to surround the movable portion 101 . The ends of the first drive beam 110a and the second drive beam 110b that are cantilevered on the -X direction side are free ends, and the ends on the +X direction side are fixed ends.

The first drive beam 110a has a first piezoelectric drive portion 112a and is driven according to a drive voltage applied to the first piezoelectric drive portion 112a. The second drive beam 110b has a second piezoelectric driver 112b and is driven according to the drive voltage applied to the second piezoelectric driver 112b.

When the first drive beam 110a and the second drive beam 110b are driven, the first torsion beam 111a and the second torsion beam 111b are twisted about the first swing axis Ey as the twist center axis, and the movable part 101 swings in the first swing. It swings around the axis Ey.

A first strain resistor 160a and a second strain resistor 160b are each disposed on the first drive beam 110a. A third strain resistor 160c and a fourth strain resistor 160d are each disposed on the second drive beam 110b.

The first strain resistor 160a and the second strain resistor 160b are resistors whose resistance values change according to the stress applied to the first drive beam 110a as the first torsion beam 111a is twisted. The third strain resistor 160c and the fourth strain resistor 160d are resistors whose resistance values change according to the stress applied to the second drive beam 110b as the second torsion beam 111b twists. The longitudinal directions of the first strain resistor 160a, the second strain resistor 160b, the third strain resistor 160c, and the fourth strain resistor 160d are along the first swing axis Ey.

Hereinafter, the first strain resistor 160a, the second strain resistor 160b, the third strain resistor 160c, and the fourth strain resistor 160d are collectively referred to as the first to fourth strain resistors 160 when not distinguished.

The first to fourth strain resistors 160 are, for example, piezo elements utilizing the piezoelectric effect that convert force applied to the piezoelectric body into voltage or convert voltage into force. In this embodiment, the material of the first to fourth strain resistors 160 is semiconductor.

Each of the pair of drive portions 130a and 130b has a plurality of beam portions 135 and a connecting portion 136 that connects the plurality of beam portions 135 by folding. The second support portion 140 supports a pair of driving portions 130a and 130b. One end of each of the pair of drive portions 130 a and 130 b is connected to the first support portion 120 , and the other end of each of the pair of drive portions 130 a and 130 b is connected to the second support portion 140 .

The connection point between the drive portion 130a and the first support portion 120 and the connection point between the drive portion 130b and the first support portion 120 are symmetrical about the center of the reflecting surface 14. FIG. Further, the connecting portion between the driving portion 130a and the second supporting portion 140 and the connecting portion between the driving portion 130b and the second supporting portion 140 are symmetrical about the center of the reflecting surface .

The driving section 130a has third piezoelectric driving sections 131a to 131f, and drives according to driving voltages applied to the third piezoelectric driving sections 131a to 131f. The driving section 130b has fourth piezoelectric driving sections 132a to 132f, and drives according to driving voltages applied to the fourth piezoelectric driving sections 132a to 132f.

By driving the pair of drive portions 130a and 130b, the movable portion 101, the first torsion beam 111a, the second torsion beam 111b, the first drive beam 110a, the second drive beam 110b, and the first support portion 120 are integrated. , and swings around the second swing axis Ex.

The second support portion 140 includes the movable portion 101, the first torsion beam 111a, the second torsion beam 111b, the first drive beam 110a, the second drive beam 110b, the first support portion 120, and the pair of drive portions 130a and 130b. It is a rectangular frame-shaped support formed to surround.

The electrode connection portion 150 is formed on the +Z side surface of the second support portion 140, and includes the first piezoelectric drive portion 112a, the second piezoelectric drive portion 112b, the third piezoelectric drive portions 131a to 131f, and the fourth piezoelectric drive portion 132a. 132f are electrically connected through electrode wiring of aluminum (Al) or the like.

The control device 11 has a detection section 330 and a drive control section 331 . The control device 11 applies drive voltages to the first piezoelectric drive section 112a, the second piezoelectric drive section 112b, the third piezoelectric drive sections 131a to 131f, and the fourth piezoelectric drive sections 132a to 132f through the electrode connection section 150. .

Based on the resistance values of the first strain resistor 160a, the second strain resistor 160b, the third strain resistor 160c, and the fourth strain resistor 160d, the detection unit 330 causes the movable unit 101 to swing about the first swing axis Ey. Output angle information. The detection unit 330 is configured by an operational amplifier or the like. The swing angle information is information indicating the swing angle of the movable portion 101 about the first swing axis Ey, or information related to the swing angle of the movable portion 101 about the first swing axis Ey.

The drive control unit 331 controls driving of the first drive beam 110a, the second drive beam 110b, and the pair of drive units 130a and 130b. Further, the drive control section 331 can control the swing angle of the movable section 101 about the first swing axis Ey by controlling the drive voltage based on the swing angle information output from the detection section 330 .

The movable device 13 is formed by, for example, etching a single SOI (Silicon On Insulator) substrate. The reflecting surface 14, the first piezoelectric driving section 112a, the second piezoelectric driving section 112b, the third piezoelectric driving sections 131a to 131f, the fourth piezoelectric driving sections 132a to 132f, the electrode connection section 150, etc. are integrally formed on the molded substrate. formed in Note that the formation of each of these components may be performed after the SOI substrate is formed, or may be performed during the formation of the SOI substrate.

As shown in FIG. 2, the SOI substrate on which the movable device 13 is formed includes a silicon support layer 161 made of single crystal silicon (Si) and a silicon oxide layer 162 formed on the silicon support layer 161 (+Z direction side). and a silicon active layer 163 made of single crystal silicon formed on the silicon oxide layer 162 . The silicon oxide layer 162 can also be called a BOX (Buried Oxide) layer.

Since the thickness of the silicon active layer 163 in the Z direction is smaller than that in the X or Y direction, the member composed only of the silicon active layer 163 functions as an elastic part having elasticity.

Note that the SOI substrate does not necessarily have to be planar, and may have a curvature or the like. Further, the member used to form the movable device 13 is not limited to the SOI substrate as long as it is a substrate that can be integrally formed by etching or the like and that can be partially elastic.

The movable portion 101 includes, for example, a circular movable portion base 102 and a reflecting surface 14 formed on the +Z side surface of the movable portion base. The movable part base 102 includes, for example, a silicon active layer 163 . Reflective surface 14 includes, for example, a thin metal film containing aluminum, gold, silver, or the like.

In the third piezoelectric drive sections 131a to 131f and the fourth piezoelectric drive sections 132a to 132f, the lower electrode 201, the piezoelectric section 202, and the upper electrode 203 are laminated in this order on the +Z side surface of the silicon active layer 163, which is the elastic section. consists of The upper electrode 203 and the lower electrode 201 contain gold (Au) or platinum (Pt), for example. The piezoelectric portion 202 includes, for example, PZT (lead zirconate titanate), which is a piezoelectric material.

A drive voltage is applied to the lower electrode 201 and the upper electrode 203 is grounded (GND). In addition, the upper electrode 203 or the lower electrode 201 may be directly connected to the electrode connection portion 150, respectively, or may be indirectly connected by connecting the electrodes to each other. Alternatively, the lower electrode 201 may be grounded (GND) and the driving voltage may be applied to the upper electrode 203 .

A rib 103 for reinforcing the movable portion is formed on the −Z side surface of the movable portion base 102 . The rib 103 includes, for example, a silicon support layer 161 and a silicon oxide layer 162, and suppresses distortion of the reflective surface 14 caused by movement. However, the rib 103 is not an essential component.

As shown in FIG. 3, the second torsion beam 111b includes a silicon active layer 163. As shown in FIG. The second piezoelectric drive section 112b is configured by laminating a lower electrode 301, a piezoelectric section 302, and an upper electrode 303 in this order on the +Z side surface of the silicon active layer 163, which is an elastic section. The upper electrode 303 and the lower electrode 301 contain gold (Au) or platinum (Pt), for example. The piezoelectric portion 302 includes, for example, PZT (lead zirconate titanate), which is a piezoelectric material.

A drive voltage is applied to the lower electrode 301 and the upper electrode 303 is grounded (GND). The upper electrode 303 or the lower electrode 301 may be directly connected to the electrode connecting portion 150, or may be indirectly connected by connecting the electrodes to each other. Alternatively, the lower electrode 301 may be grounded (GND) and the driving voltage may be applied to the upper electrode 303 .

In the present embodiment, the case where the piezoelectric portion 202 is formed only on one surface (the surface on the +Z side) of the silicon active layer 163, which is the elastic portion, has been described as an example. surface), or may be provided on both one surface and the other surface of the elastic portion.

Further, as long as the movable portion 101 can be driven around the first swing axis Ey and around the second swing axis Ex, the shape of each constituent portion is not limited to the shape shown in the present embodiment. For example, the first torsion beam 111a and the second torsion beam 111b, and the first drive beam 110a and the second drive beam 110b may have curvatures.

Further, on the +Z side surface of the upper electrode 303 of the first drive beam 110a and the second drive beam 110b, on the +Z side surface of the first support section 120, and on the +Z side of the upper electrode 203 of the pair of drive sections 130a and 130b. An insulating layer made of a silicon oxide film may be formed on at least one of the surface of the second support portion 140 and the surface on the +Z side of the second support portion 140 .

Electrode wiring is provided on the insulating layer, and only connection spots where the upper electrode 203, the upper electrode 303, the lower electrode 201 and the lower electrode 301 are connected to the electrode wiring are partially covered with the insulating layer as openings. Do not remove or form an insulating layer. With this configuration, the degree of freedom in designing the first drive beam 110a and the second drive beam 110b, the pair of drive portions 130a and 130b, and the electrode wiring can be increased, and short circuits due to contact between the electrodes can be suppressed. The silicon oxide film also functions as an antireflection material.

<Control by control device 11>
Control by the control device 11 that drives the first drive beam 110a and the second drive beam 110b of the movable device 13 will be briefly described.

When a positive or negative voltage is applied in the polarization direction, the piezoelectric portion 302 of the first drive beam 110a and the second drive beam 110b undergoes deformation (e.g., expansion and contraction) proportional to the potential of the applied voltage, which is the so-called reverse piezoelectric effect. demonstrate. The first drive beam 110a and the second drive beam 110b swing the movable portion 101 using the reverse piezoelectric effect.

The angle formed by the XY plane and the reflecting surface 14 when the reflecting surface 14 of the movable portion 101 is tilted in the +Z direction or the −Z direction with respect to the XY plane is called a deflection angle. The +Z direction is assumed to be a positive deflection angle, and the −Z direction is assumed to be a negative deflection angle.

When drive voltages are applied in parallel to the piezoelectric portions 302 via the upper electrode 303 and the lower electrode 301, the respective piezoelectric portions 302 are deformed. Due to the deformation of the piezoelectric section 302, the first piezoelectric driving section 112a and the second piezoelectric driving section 112b bend and deform. As a result, the driving force around the first swing axis Ey acts on the movable portion 101 through the twisting of the first torsion beam 111a and the second torsion beam 111b, and the movable portion 101 swings around the first swing axis Ey. move. The driving voltage applied to the first driving beam 110 a and the second driving beam 110 b is controlled by the driving control section 331 .

The driving control unit 331 applies driving voltages having a predetermined sinusoidal waveform to the first piezoelectric driving unit 112a and the second piezoelectric driving unit 112b in parallel, thereby driving the movable unit 101 around the first oscillation axis Ey. It can be oscillated by the cycle of the voltage.

For example, when the frequency of the drive voltage is set to about 20 kHz, which is approximately the same as the resonance frequency of the first torsion beam 111a and the second torsion beam 111b, the torsion of the first torsion beam 111a and the second torsion beam 111b Using the occurrence of mechanical resonance, the movable part 101 can be resonantly oscillated at about 20 kHz.

[First embodiment]
<Detailed configuration example around the first to fourth strain resistors 160>
FIG. 4 is a plan view illustrating the detailed configuration around the first to fourth strain resistors 160. As shown in FIG. As shown in FIG. 4, the first strain resistor 160a is arranged on the free end side (-X direction side) of the first drive beam 110a with respect to the first swing axis Ey. The third strain resistor 160c is arranged closer to the free end side (-X direction side) of the second drive beam 110b than the first swing axis Ey. The second strain resistor 160b is arranged closer to the fixed end side (+X direction side) of the first drive beam 110a than the first swing axis Ey. The fourth strain resistor 160d is arranged closer to the fixed end side (+X direction side) of the second drive beam 110b than the first swing axis Ey. The first to fourth strain resistors 160 form a Wheatstone bridge circuit.

The distance Da is the distance between the first strain resistor 160a and the first swing axis Ey. The distance Db is the distance between the second strain resistor 160b and the first swing axis Ey. A distance Dc is the distance between the third strain resistor 160c and the first swing axis Ey. A distance Dd is the distance between the fourth strain resistor 160d and the first swing axis Ey.

In this embodiment, the distances Da, Db, Dc, and Dd are set so that the rates of change in the resistance values of the first to fourth strain resistors 160 due to the torsion of the first torsion beam 111a and the second torsion beam 111b are substantially equal. is adjusted to As a result of this adjustment, the distance Da is longer than the distance Db, and the distance Dc is longer than the distance Dd.

<Action of First to Fourth Strain Resistors 160>
When a drive voltage is applied to drive the first drive beam 110a and the second drive beam 110b, the first drive beam 110a is twisted by the first torsion beam 111a, and the second drive beam 110b is twisted by the second torsion beam 111b. stress is applied by the torsion of .

In the first drive beam 110a and the second drive beam 110b, in the X direction, a compressive stress is applied to the free end side and a tensile stress is applied to the fixed end side. Also, the stress value on the free end side is smaller than the stress value on the fixed end side, and the stress value increases toward the rounded fillet side. On the other hand, in the Y direction, tensile stress is applied to the free end side and compressive stress is applied to the fixed end side, and the stress value on the free end side is smaller than the stress value on the fixed end side. This stress changes the resistance values of the first strain resistor 160a, the second strain resistor 160b, the third strain resistor 160c, and the fourth strain resistor 160d.

When the distance Da and the distance Dc are substantially equal, the stresses applied to the first drive beam 110a and the second drive beam 110b are equal at each position of the first strain resistor 160a and the third strain resistor 160c. Similarly, when the distance Db and the distance Dd are substantially equal, the stresses applied to the first drive beam 110a and the second drive beam 110b are equal at each position of the second strain resistor 160b and the fourth strain resistor 160d.

FIG. 5 is a diagram illustrating a bridge circuit having first through fourth strain resistors 160. As shown in FIG. When a constant current i is applied to the Wheatstone bridge circuit, the resistance value R1 of the first strain resistor 160a and the third strain resistor 160c is represented by R ₀ +ΔR ₁ , and the resistance value R1 of the second strain resistor 160b and the fourth strain resistor A resistance value R2 of 160d is represented by R ₀ +ΔR ₂ . Here, R ₀ represents the resistance value of each of the first to fourth strain resistors 160 when no stress is applied.

A voltage signal ΔV output from the Wheatstone bridge circuit is represented by the following equation (1) according to Kirchhoff's law.
ΔV=V1−V2={(R ₀ +ΔR ₁ ) ² −(R ₀ +ΔR ₂ ) ² }/(4×R ₀ +2×ΔR ₂ +2×ΔR ₁ )×i=(ΔR ₁ /R ₀ −ΔR ₂ /R ₀ )×R ₀ ×i/2 (1)

The rate of change ΔR/R ₀ of the strain resistance when a predetermined stress is applied is expressed by the following equation (2), considering up to the second-order term.
ΔR/R ₀ ≈π′11×σ _x +π′12×σ _y +π′66×σ _xy +π′111×σ _x ² +2×π′112×σ _x ×σ _y +π′122×σ _y ² +π′166×σ _xy ² (2)
Here, π'11, π'12, π'66, π'111, π'112, π'122, and π'166 each represent a strain resistance coefficient.

Let σa _x , σa _y , and σa _xy be the stresses applied to the first strain resistor 160a and the third strain resistor 160c, respectively, and σb _x , σb _y , and σb _xy be the stresses applied to the second strain resistor 160b and the fourth strain resistor 160d, respectively. and

Substituting the formula (2) into the formula (1) and transforming it gives the following formula (3).
ΔV=1/2 {π′11×(σa _x −σb _x )+π′12×(σa _y −σb _y )+π′16×(σa _xy −σb _xy )+π′111×(σa _x ² −σb _x ² ) + 2 x π'112 x (σa _x x σa _y - σb _x x σb _y ) + π' 122 x (σa _y ² - σb _y ² ) + π' 166 x (σa _xy ² - _{σb xy} ² )} x R ₀ ×i (3)

In the case of a cantilever beam, if the first to fourth strain resistors 160 are arranged symmetrically around the first swing axis Ey corresponding to the torsion central axis of the first torsion beam 111a and the second torsion beam 111b, , the effect of the quadratic term cannot be ignored due to the different stresses at each position. As a result, the relationship between the swing angle of the movable portion 101 and the swing angle information output by the detector 330 is no longer linear. However, when the stress is small, the second-order term becomes negligible, so that the relationship between the swing angle of the movable portion 101 and the swing angle information output by the detection portion 330 becomes substantially linear.

Since the order of the strain resistance coefficient is the following value, it cannot be ignored when the stress exceeds several tens of MPa (10 ⁸ ). That is, the first-order term is 10 ⁻¹⁰ ×10 ⁸ =10 ⁻² order, and the second-order term is 10 ⁻¹⁹ ×10 ¹⁶ =10 ⁻³ order.

In this embodiment, the first strain resistor 160a and the third strain resistor 160c are arranged on the free end side with respect to the first swing axis Ey, and the first strain resistor 160a and the third strain resistor 160c are arranged on the first swing axis Ey. It is arranged on the fixed end side with respect to Ey. Also, the distances Da and Dc are set longer than the distances Db and Dd, and the distances Da, Db, Dc and Dd are adjusted so that the rate of change in resistance caused by stress is about the same. As a result, the relationship between the swing angle of the movable portion 101 and the voltage signal ΔV output from the Wheatstone bridge circuit becomes substantially linear, and the relationship between the swing angle of the movable portion 101 and the voltage signal ΔV can be expressed by a simple linear expression can be expressed by

<Effects of first to fourth strain resistors 160>
Next, effects of the first to fourth strain resistors 160 will be described.

Conventionally, as a movable device using a MEMS device, a pair of torsion beams supported on both sides and supporting a movable part so as to be able to swing, and a pair of torsion beams arranged at symmetrical positions about the swing axis of the movable part and strain resistors, and is capable of detecting the swing angle of a movable part using a Wheatstone bridge circuit composed of a pair of strain resistors and a pair of external fixed elements.

However, in the structure in which the drive beam is cantilevered, the magnitude of the stress applied to the drive beam according to the torsion of the torsion beam is not symmetrical with respect to the swing axis of the movable portion. Therefore, if the strain resistors are arranged symmetrically with the swing axis of the movable part as the center of symmetry, the relationship between the swing angle of the movable part and the voltage signal from the Wheatstone bridge circuit will not be linear, and the swing angle will be detected. In some cases, the accuracy of

In the movable device 13 according to this embodiment, the first strain resistor 160a is arranged closer to the free end of the first drive beam 110a than the first swing axis Ey, and the third strain resistor 160c is arranged on the first swing axis Ey. The second strain resistor 160b is placed closer to the free end of the second drive beam 110b than Ey, the second strain resistor 160b is placed closer to the fixed end of the first drive beam 110a than the first swing axis Ey, and the fourth strain resistor 160d is , is disposed closer to the fixed end of the second drive beam 110b than the first swing axis Ey. Further, the distance Da between the first strain resistor 160a and the first swing axis Ey is longer than the distance Db between the second strain resistor 160b and the first swing axis Ey, and the third strain resistor 160c and A distance Dc between the first swing axis Ey is longer than a distance Dd between the fourth strain resistor 160d and the first swing axis Ey.

With the above configuration, the rate of change of each resistance value of the first to fourth strain resistors 160 becomes substantially equal, so that the relationship between the swing angle of the movable part 101 and the voltage signal ΔV output from the Wheatstone bridge circuit is substantially linear. Therefore, the relationship between the swing angle of the movable portion 101 and the voltage signal ΔV can be expressed by a linear expression. As a result, in the present embodiment, the swing angle of the movable portion 101 can be detected with high accuracy, which facilitates control of the swing angle of the movable portion 101 and enables highly accurate control. As a result, in this embodiment, it is possible to provide the movable device 13 with excellent accuracy in detecting the swing angle of the movable portion 101 .

Further, in the present embodiment, a pair of driving portions 130a and 130b for swinging the movable portion 101 around the second swinging axis Ex intersecting the first swinging axis Ey are provided, and the first to fourth strain resistors 160 are provided. The longitudinal direction of each of the (first to fourth strain resistors) is the direction along the first swing axis Ey. With this configuration, the movable device 13 can swing the movable portion 101 around the first swing axis Ey and the second swing axis Ex, and the light incident on the reflecting surface 14 of the movable portion 101 can be It can scan in two axial directions.

Further, in the present embodiment, the second support portion 140 that supports the pair of drive portions 130a and 130b is provided, and each of the pair of drive portions 130a and 130b includes a plurality of beam portions 135 and a plurality of beam portions 135. and a connecting portion 136 for folding connection. One end of each of the pair of drive portions 130 a and 130 b is connected to the first support portion 120 , and the other end of each of the pair of drive portions 130 a and 130 b is connected to the second support portion 140 . With this configuration, the movable device 13 can swing the movable portion 101 around the second swing axis Ex with a large swing angle.

However, the pair of drive portions 130a and 130b and the second support portion 140 are not essential components of the movable device 13 according to the embodiment. Even if the movable device 13 does not have the pair of drive portions 130 a and 130 b and the second support portion 140 , it is possible to obtain the effect of being excellent in the accuracy of detecting the swing angle of the movable portion 101 .

Further, in the present embodiment, the first to fourth strain resistors 160 are piezo elements made of semiconductor. It is conceivable to use PZT (lead zirconate titanate) as the material for the first to fourth strain resistors 160, but the stress accompanying the twisting of the first torsion beam 111a and the second torsion beam 111b is large. Therefore, if a strain resistor made of PZT (lead zirconate titanate) is used, the stress may cause the strain resistor to separate from the silicon substrate. In this embodiment, the first to fourth strain resistors 160 made of a semiconductor material are used, and the first to fourth strain resistors 160 are formed as diffusion layers, so such peeling does not occur.

In this embodiment, the distance Da and the distance Dc are substantially equal, and the distance Db and the distance Dd are substantially equal, but the configuration is not limited to this. In the first to fourth strain resistors 160, if the resistance change rate according to the stress applied to the first drive beam 110a and the second drive beam 110b is approximately equal, the distance Da and the distance Dc may not necessarily be equal, and the distance Db and the distance Dd are not necessarily equal.

In addition, in the present embodiment, the second strain resistor 160b is arranged closer to the fixed end of the first drive beam 110a than the first swing axis Ey, and the fourth strain resistor 160d is placed second than the first swing axis Ey. Although the configuration arranged on the fixed end side of the drive beam 110b is illustrated, it is not limited to this. If the distance Da is longer than the distance Db and the distance Dc is longer than the distance Dd, the second strain resistor 160b is arranged closer to the free end of the first drive beam 110a than the first swing axis Ey, and the fourth strain resistor 160d may be arranged closer to the free end of the second drive beam 110b than the first swing axis Ey.

<Modification>
Various modifications are possible for the movable device according to the embodiment. Each modification will be described below. In addition, the same code|symbol is attached|subjected to the structure part same as the movable apparatus 13 which concerns on embodiment mentioned above, and the overlapping description is abbreviate|omitted suitably.

(First modification)
FIG. 6 is a plan view illustrating the detailed configuration around the first to fourth strain resistors 160A according to the first modification. FIG. 7 is a cross-sectional view along the VII-VII section line of FIG. FIG. 8 is a diagram illustrating a bridge circuit including first to fourth strain resistors 160A.

In this modification, the longitudinal directions of the first torsion beam 111a and the second torsion beam 111b in silicon (Si) on the crystal plane (001) are substantially parallel to the first swing axis Ey. When the crystal axis direction of the first torsion beam 111a and the second torsion beam 111b is <110>, the first to fourth strain resistors 160A, which are P-type piezoresistors, are arranged so that their longitudinal direction is the direction of the first torsion beam. 111a and the second torsion beam 111b are arranged so as to be oriented substantially in the same direction as the respective longitudinal directions. That is, the longitudinal direction of each of the first torsion beam 111a and the second torsion beam 111b is parallel to the <110> direction. It may be a P-type resistor to silicon in an N-type substrate.

The first to fourth strain resistors 160A include a first strain resistor 160Aa, a second strain resistor 160Ab, a third strain resistor 160Ac and a fourth strain resistor 160Ad. A first strain resistor 160Aa and a third strain resistor 160Ab are arranged on the first drive beam 110a, and a second strain resistor 160Ac and a fourth strain resistor 160Ad are arranged on the second drive beam 110b.

In this modification, an N-well may be formed in P-type silicon and a P-type resistor may be formed in the N-well. In this case, the P-type substrate potential is equal to or lower than the minimum potential applied to the first to fourth strain resistors 160A, and the N-WELL potential is equal to the maximum voltage applied to the first to fourth strain resistors 160A and the parasitic potential. A potential equal to or higher than the forward voltage Vf of the PN diode.

When the longitudinal directions of the first to fourth strain resistors 160A are arranged substantially parallel to the longitudinal directions of the first torsion beam 111a and the second torsion beam 111b, the strain resistance coefficients of the first to fourth strain resistors 160A are You can set the maximum. However, even if the angle deviates to some extent, the first to fourth strain resistors 160A can be used because the sensitivity of the strain resistance coefficients of the first to fourth strain resistors 160A can be secured to some extent as long as it is up to about ±30 degrees. be.

A contact portion connecting the metal wiring with the first to fourth strain resistors 160A and the silicon substrate is a diffusion layer having an impurity concentration higher than that of the first to fourth strain resistors 160A and the silicon substrate. This configuration can improve the contactability with the metal wiring. Although the P+ diffusion is included in the P- diffusion in FIGS. 6 to 8, the P+ diffusion edge and the P- diffusion edge may be flat without a step. This point also applies to FIGS. 12 to 14 and FIGS. 18 to 20 shown below.

6 and 7, connection terminals Pd5 and Pd7 are connection terminals that take the NW potential. In general, connection terminals Pd5 and Pd7 are at maximum potential. Connection terminals Pd6 and Pd8 are connection terminals that take a P-type substrate potential. In general, the connection terminals Pd5 and Pd7 are at the minimum potential, most of which are at the GND potential. All of the connection terminals Pd1 to Pd8 are made of a metal material.

In FIG. 8, a circuit 81 indicates a Wheatstone bridge circuit when applying a constant voltage, and a circuit 82 indicates a Wheatstone bridge circuit when applying a constant current.

The effects of the first to fourth strain resistors 160A are the same as those of the first to fourth strain resistors 160A.

(Second modification)
FIG. 9 is a plan view illustrating the detailed configuration around the first to fourth strain resistors 160B according to the second modification. 10 is a cross-sectional view taken along line XX of FIG. 9. FIG. FIG. 11 is a diagram illustrating a bridge circuit including first to fourth strain resistors 160B.

In this modification, when the crystal axis direction of the first torsion beam 111a and the second torsion beam 111b in silicon on the crystal plane (001) plane is <110>, the first to second N-type piezoresistors The four strain resistors 160B are arranged such that their longitudinal directions form approximately 45 degrees with the respective longitudinal directions of the first torsion beam 111a and the second torsion beam 111b. It may be an N-type resistor to the silicon of the P-type substrate. In this case, the potential of the P-type substrate becomes equal to or lower than the minimum potential applied to the first to fourth strain resistors 160B.

The first to fourth strain resistors 160B include a first strain resistor 160Ba, a second strain resistor 160Bb, a third strain resistor 160Bc and a fourth strain resistor 160Bd. A first strain resistor 160Ba and a third strain resistor 160Bb are arranged on the first drive beam 110a, and a second strain resistor 160Bc and a fourth strain resistor 160Bd are arranged on the second drive beam 110b.

If the first to fourth strain resistors 160B are arranged such that their longitudinal directions form an angle of approximately 45 degrees with the respective longitudinal directions of the first torsion beam 111a and the second torsion beam 111b, the strain of the first to fourth strain resistors 160B is The largest resistance coefficient can be set. However, even if the angle deviates to some extent, the first to fourth strain resistors 160B can be used because the sensitivity of the strain resistance coefficients of the first to fourth strain resistors 160B can be secured to some extent as long as it is up to about ±15 degrees. be.

9 and 10, Pd6 and Pd8 are connection terminals that take the P-type substrate potential. Generally, connection terminals Pd4, Pd6 and Pd8 are at GND potential.

In FIG. 11, a circuit 83 indicates a Wheatstone bridge circuit when applying a constant voltage, and a circuit 84 indicates a Wheatstone bridge circuit when applying a constant current.

The effects of the first to fourth strain resistors 160B are the same as those of the first to fourth strain resistors 160B.

(Third modification)
FIG. 12 is a plan view illustrating the detailed configuration around the first to fourth strain resistors 160C according to the third modification. 13 is a cross-sectional view taken along line XIII--XIII of FIG. 12. FIG. FIG. 14 is a diagram illustrating a bridge circuit including first to fourth strain resistors 160C.

In this modification, when the crystal axis direction of the first torsion beam 111a and the second torsion beam 111b in silicon on the crystal plane (001) plane is <100>, the first to second N-type piezoresistors The four strain resistors 160C are arranged such that their longitudinal directions are substantially the same as the longitudinal directions of the first torsion beam 111a and the second torsion beam 111b. That is, the longitudinal direction of each of the first torsion beam 111a and the second torsion beam 111b is parallel to the <100> direction. It may be an N-type resistor to the silicon of the P-type substrate. In this case, the potential of the P-type substrate becomes equal to or lower than the minimum potential applied to the first to fourth strain resistors 160C.

The first to fourth strain resistors 160C include a first strain resistor 160Ca, a second strain resistor 160Cb, a third strain resistor 160Cc and a fourth strain resistor 160Cd. A first strain resistor 160Ca and a third strain resistor 160Cb are arranged in the first drive beam 110a, and a second strain resistor 160Cc and a fourth strain resistor 160Cd are arranged in the second drive beam 110b.

When the first to fourth strain resistors 160C are arranged such that their longitudinal directions are substantially parallel to the longitudinal directions of the first torsion beam 111a and the second torsion beam 111b, the strain resistances of the first to fourth strain resistors 160C The largest coefficient can be set. However, even if the angle deviates to some extent, the first to fourth strain resistors 160C can be used because the sensitivity of the strain resistance coefficients of the first to fourth strain resistors 160C can be secured to some extent as long as it is up to about ±15 degrees. be.

In FIGS. 12 and 13, Pd6 and Pd8 are connection terminals that take the P-type substrate potential. Generally, connection terminals Pd4, Pd6 and Pd8 are at GND potential.

In FIG. 14, a circuit 85 indicates a Wheatstone bridge circuit when applying a constant voltage, and a circuit 86 indicates a Wheatstone bridge circuit when applying a constant current.

The effects of the first to fourth strain resistors 160C are the same as those of the first to fourth strain resistors 160C.

(Fourth modification)
FIG. 15 is a plan view illustrating the detailed configuration around the first to fourth strain resistors 160D according to the fourth modification. 16 is a cross-sectional view along the XVI--XVI section line of FIG. 15. FIG. FIG. 17 is a diagram illustrating a bridge circuit including first to fourth strain resistors 160D.

In this modification, when the crystal axis direction of the first torsion beam 111a and the second torsion beam 111b in silicon on the crystal plane (001) plane is <100>, the first to second P-type piezoresistors The four strain resistors 160D are arranged such that their longitudinal directions form approximately 45 degrees with the respective longitudinal directions of the first torsion beam 111a and the second torsion beam 111b. It can also be a P-type resistor for N-type substrate silicon. In this case, the potential of the N-type substrate becomes equal to or higher than the maximum potential applied to the first to fourth strain resistors 160D.

An N-well may be formed in P-type silicon and a P-type resistor formed within the N-well. In this case, the potential of the P-type substrate is equal to or lower than the minimum potential applied to the first to fourth strain resistors 160D, and the N-WELL potential is the maximum voltage applied to the first to fourth strain resistors 160D. and the forward voltage Vf of the parasitic PN diode.

The first to fourth strain resistors 160D include a first strain resistor 160Da, a second strain resistor 160Db, a third strain resistor 160Dc and a fourth strain resistor 160Dd. A first strain resistor 160Da and a third strain resistor 160Db are arranged on the first drive beam 110a, and a second strain resistor 160Dc and a fourth strain resistor 160Dd are arranged on the second drive beam 110b.

When the first to fourth strain resistors 160D are arranged such that their longitudinal directions are approximately 45 degrees with the respective longitudinal directions of the first torsion beam 111a and the second torsion beam 111b, the strain of the first to fourth strain resistors 160D is The largest resistance coefficient can be set. However, even if the angle deviates to some extent, the first to fourth strain resistors 160D can be used because the sensitivity of the strain resistance coefficients of the first to fourth strain resistors 160D can be secured to some extent as long as it is up to about ±30 degrees. be.

15 and 16, Pd5 and Pd7 are connection terminals that take the NW potential. In general, connection terminals Pd5 and Pd7 are at the maximum potential. Pd6 and Pd8 are connection terminals for taking the potential of the P-type substrate. In general, the connection terminals Pd4, Pd6 and Pd8 are at the minimum potential, and most of them are at the GND potential.

In FIG. 17, a circuit 87 indicates a Wheatstone bridge circuit when applying a constant voltage, and a circuit 88 indicates a Wheatstone bridge circuit when applying a constant current.

The effects of the first to fourth strain resistors 160D are the same as those of the first to fourth strain resistors 160D.

(Fifth to eighth modifications)
FIG. 18 is a plan view illustrating the detailed configuration around the first to fourth strain resistors 160E according to the fifth modification. 19 is a cross-sectional view along the XIX-XIX section line of FIG. 18. FIG. FIG. 20 is a diagram of an example of a bridge circuit including first to fourth strain resistors E. FIG.

FIG. 21 is a plan view illustrating the detailed configuration around the first to fourth strain resistors 160F according to the sixth modification. 22 is a cross-sectional view taken along line XXII--XXII of FIG. 21. FIG. 23 is a diagram illustrating a bridge circuit including first to fourth strain resistors F. FIG.

FIG. 24 is a plan view illustrating the detailed configuration around the first to fourth strain resistors 160G according to the seventh modification. 25 is a cross-sectional view along the XXV--XXV cutting line of FIG. 24. FIG. 26 is a diagram illustrating a bridge circuit including first to fourth strain resistors G. FIG.

FIG. 27 is a plan view illustrating the detailed configuration around the first to fourth strain resistors 160H according to the eighth modification. 28 is a cross-sectional view taken along line XXVIII--XXVIII of FIG. 27. FIG. 29 is a diagram illustrating a bridge circuit including first to fourth strain resistors H. FIG.

While the first to fourth modifications use a P-type substrate, the fifth to eighth modifications use an N-type substrate. The effects of the first to fourth strain resistors 160E, 160F, 160G and 160H in the fifth to eighth modifications are the same as those of the first to fourth strain resistors 160. FIG.

[Other preferred embodiments]
Movable device 13 concerning an embodiment mentioned above is applicable to various systems and devices. Below, the application example to various systems and apparatuses of the movable apparatus 13 is demonstrated.

<Optical scanning system>
First, an optical scanning system to which the movable device of this embodiment is applied will be described in detail with reference to FIGS. 30 to 33. FIG. A schematic diagram of an example of an optical scanning system is shown in FIG. As shown in FIG. 30, the optical scanning system 10 is a system that optically scans a surface 15 to be scanned by deflecting light emitted from a light source device 12 by a reflecting surface 14 of a movable device 13 under the control of a control device 11 . be.

The optical scanning system 10 includes a control device 11 , a light source device 12 and a movable device 13 having a reflecting surface 14 .

The control device 11 is an electronic circuit unit including, for example, a CPU (Central Processing Unit) and an FPGA (Field-Programmable Gate Array). The movable device 13 is, for example, a MEMS device that has a reflective surface 14 and the reflective surface 14 is movable.

The light source device 12 is, for example, a laser device that emits laser light. Note that the scanned surface 15 is, for example, a screen.

The control device 11 generates control commands for the light source device 12 and the movable device 13 based on the acquired optical scanning information, and outputs drive signals to the light source device 12 and the movable device 13 based on the control commands. The light source device 12 irradiates the light source based on the input drive signal. The movable device 13 rotationally vibrates the reflecting surface 14 in at least one of the directions of one axis and the directions of two axes based on the input drive signal.

As a result, for example, the reflecting surface 14 of the movable device 13 is reciprocatingly rotated and vibrated in two axial directions within a predetermined range by the control of the control device 11 based on image information, which is an example of optical scanning information. An arbitrary image can be projected onto the surface 15 to be scanned by optically scanning the irradiated light from the light source device 12 incident on the surface 14 by deflecting it around a certain axis. In addition, the detail of the movable apparatus of this embodiment and the detail of control by a control apparatus are mentioned later.

Next, an example hardware configuration of the optical scanning system 10 will be described with reference to FIG. FIG. 31 is a hardware configuration diagram of an example of the optical scanning system 10. As shown in FIG. As shown in FIG. 31, the optical scanning system 10 includes a control device 11, a light source device 12 and a movable device 13, which are electrically connected to each other. Among these, the control device 11 includes a CPU 20 , a RAM 21 (Random Access Memory), a ROM 22 (Read Only Memory), an FPGA 23 , an external I/F 24 , a light source device driver 25 and a movable device driver 26 .

The CPU 20 is an arithmetic device that reads programs and data from a storage device such as a ROM 22 onto a RAM 21 and executes processing to achieve overall control and functions of the control device 11 .

The RAM 21 is a volatile storage device that temporarily holds programs and data.

The ROM 22 is a nonvolatile storage device that can retain programs and data even when the power is turned off, and stores processing programs and data that the CPU 20 executes to control each function of the optical scanning system 10 . there is

The FPGA 23 is a circuit that outputs control signals suitable for the light source device driver 25 and the movable device driver 26 according to the processing of the CPU 20 .

The external I/F 24 is, for example, an interface with an external device, network, or the like. External devices include, for example, host devices such as PCs (Personal Computers), and storage devices such as USB memories, SD cards, CDs, DVDs, HDDs, and SSDs. The network is, for example, a CAN (Controller Area Network) of an automobile, a LAN (Local Area Network), the Internet, or the like. The external I/F 24 may be configured to enable connection or communication with an external device, and the external I/F 24 may be prepared for each external device.

The light source device driver 25 is an electric circuit that outputs a drive signal such as a drive voltage to the light source device 12 according to the input control signal.

The mobile device driver 26 is an electric circuit that outputs a drive signal such as a drive voltage to the mobile device 13 according to the input control signal.

In the control device 11 , the CPU 20 acquires optical scanning information from an external device or network via the external I/F 24 . It should be noted that any configuration may be used as long as the CPU 20 can acquire the optical scanning information. A storage device may be provided and the optical scanning information may be stored in the storage device.

Here, the optical scanning information is information indicating how to optically scan the surface 15 to be scanned. For example, when an image is displayed by optical scanning, the optical scanning information is image data. Further, for example, when optical writing is performed by optical scanning, the optical scanning information is writing data indicating the writing order and writing location. In addition, for example, when object recognition is performed by optical scanning, the optical scanning information is irradiation data indicating the timing and irradiation range of irradiation with light for object recognition.

The control device 11 can implement the functional configuration described below by means of commands from the CPU 20 and the hardware configuration shown in FIG.

Next, the functional configuration of the controller 11 of the optical scanning system 10 will be described with reference to FIG. FIG. 32 is a functional block diagram of an example of the controller 11 of the optical scanning system.

As shown in FIG. 32, the control device 11 has a control section 30 and a drive signal output section 31 as functions.

The control unit 30 is implemented by, for example, the CPU 20 and the FPGA 23 , acquires optical scanning information from an external device, converts the optical scanning information into control signals, and outputs the control signals to the drive signal output unit 31 . For example, the control unit 30 acquires image data as optical scanning information from an external device or the like, generates a control signal from the image data through predetermined processing, and outputs the control signal to the drive signal output unit 31 . The drive signal output unit 31 is realized by the light source device driver 25, the movable device driver 26, etc., and outputs a drive signal to the light source device 12 or the movable device 13 based on the input control signal.

The drive signal is a signal for controlling driving of the light source device 12 or the movable device 13 . For example, in the light source device 12, it is a driving voltage for controlling the irradiation timing and irradiation intensity of the light source. Further, for example, in the movable device 13 , it is a drive voltage for controlling the timing and movable range for moving the reflecting surface 14 of the movable device 13 .

Next, a process of optically scanning the surface 15 to be scanned by the optical scanning system 10 will be described with reference to FIG. FIG. 33 is a flowchart of an example of processing related to the optical scanning system.

In step S11, the control unit 30 acquires optical scanning information from an external device or the like. In step S<b>12 , the control section 30 generates a control signal from the acquired optical scanning information and outputs the control signal to the drive signal output section 31 . In step S13, the drive signal output unit 31 outputs a drive signal to the light source device 12 and the movable device 13 based on the input control signal. In step S14, the light source device 12 performs light irradiation based on the input drive signal. Further, the movable device 13 rotates and vibrates the reflecting surface 14 based on the input drive signal. By driving the light source device 12 and the movable device 13, light is deflected in an arbitrary direction and optically scanned.

In the optical scanning system 10, one control device 11 has a device and functions for controlling the light source device 12 and the movable device 13. The control device for the light source device and the control device for the movable device, It may be provided separately.

In the optical scanning system 10, one control device 11 is provided with the functions of the control section 30 of the light source device 12 and the movable device 13 and the function of the drive signal output section 31, but these functions exist as separate entities. Alternatively, for example, a configuration in which a drive signal output device having a drive signal output section 31 is provided separately from the control device 11 having the control section 30 may be employed. In the optical scanning system 10, the movable device 13 having the reflecting surface 14 and the control device 11 may constitute an optical deflection system that deflects the light.

In this manner, by applying the movable device 13 of the embodiment to an optical scanning system, it is possible to accurately control the oscillation of the movable portion 101 and provide an optical scanning system capable of performing optical scanning with high accuracy.

<Distance measuring device>
Next, a distance measuring device to which the movable device of the present embodiment is applied will be described in detail with reference to FIGS. 34 to 36. FIG. A distance measuring device is a device for measuring a distance to an object in a target direction, and is, for example, a laser radar device.

34 and 35 are schematic diagrams of an automobile in which a laser radar device is mounted in a lamp section unit in which a headlamp of the automobile is mounted. Also, FIG. 36 is a schematic diagram of an example of a laser radar device.

As shown in FIGS. 34 and 35, a laser radar device 700 is mounted, for example, on an automobile 701, optically scans a target direction, and receives reflected light from a target object 702 existing in the target direction. The distance to the target object 702 is measured. An automobile 701 is an example of a vehicle and an example of a moving object.

As shown in FIG. 36, the laser light emitted from the light source device 12 passes through an incident optical system composed of a collimator lens 703, which is an optical system that converts divergent light into substantially parallel light, and a plane mirror 704, and is reflected. A movable device 13 having a surface 14 is scanned in one or two axes. Then, the light is projected onto an object 702 in front of the device through a projection lens 705 or the like, which is a projection optical system. The light source device 12 and the movable device 13 are driven and controlled by the control device 11 . Reflected light reflected by the target object 702 is photodetected by a photodetector 709 . That is, the reflected light is received by an imaging device 707 via a condensing lens 706 or the like, which is an incident light detecting and receiving optical system, and the imaging device 707 outputs a detection signal to a signal processing device 708 . The signal processing device 708 performs predetermined processing such as binarization and noise processing on the input detection signal, and outputs the result to the distance measurement circuit 710 .

The distance measuring circuit 710 detects the target object based on the time difference between the timing at which the light source device 12 emits laser light and the timing at which the photodetector 709 receives the laser light, or the phase difference for each pixel of the image sensor 707 that receives the light. The presence or absence of the object 702 is recognized, and distance information to the target object 702 is calculated.

Since the movable device 13 having the reflecting surface 14 is less likely to be damaged than a polygonal mirror and is small, it is possible to provide a compact radar device with high durability. Such a laser radar device is attached to, for example, a vehicle, an aircraft, a ship, a robot, or the like, and can optically scan a predetermined range to measure the presence or absence of an obstacle and the distance to the obstacle.

Although the laser radar device 700 has been described as an example of the distance measuring device, the distance measuring device performs optical scanning by controlling the movable device 13 having the reflecting surface 14 with the control device 11, and the photodetector Any device that measures the distance to the target object 702 by receiving reflected light from a light source is acceptable, and is not limited to the above-described embodiments.

For example, biometric authentication that recognizes an object by calculating object information such as shape from distance information obtained by optically scanning the hand or face, recording and referring to it, or recognizing an intruder by optically scanning the target range. The present invention can also be applied to a security sensor, a component of a three-dimensional scanner that calculates and recognizes object information such as shape from distance information obtained by optical scanning, and outputs it as three-dimensional data. Therefore, the laser radar device 700 can also be said to be an example of an object recognition device.

In this way, by applying the movable device 13 of the embodiment to a distance measuring device, it is possible to accurately control the oscillation of the movable portion 101 and provide a distance measuring device capable of performing optical scanning with high accuracy. The measuring range of the distance measuring device can be kept constant at the desired dimensions.

<Measuring device>
Next, a measuring device to which the movable device 13 according to the embodiment is applied will be described in detail with reference to FIGS. 37 and 38. FIG. Here, a three-dimensional measuring device that performs three-dimensional measurement of an object using a pattern projection method is taken as an example of the measuring device. FIG. 37 is a block diagram showing an example of the configuration of a three-dimensional measuring device; FIG. 38 is a diagram showing a state in which a measurement pattern is projected onto an object by the three-dimensional measurement device.

As shown in FIG. 37 , the three-dimensional measuring device 1 has a measurement information acquisition unit 20 and a control unit 300 .

The measurement information acquisition unit 20 has a projection device 2 and a camera device 21 . The projection device 2 shown in FIG. 37 has a VCSEL array (vertical cavity surface emitting laser array: Vertical Cavity Surface Emitting LASER) 3 , an optical system 4 , and a movable device 13 . By using the VCSEL array 3 as the light source, it is possible to narrow the light emission interval and form a plurality of condensing points.

Under the control of the control section 310 of the control unit 300, the measurement information acquisition unit 20 causes the movable device 13 to deflect the light from the plurality of light emitting elements included in the VCSEL array 3, and projects the light onto the object in the measurement area. The control unit 310 controls the luminance and lighting timing of each light emitting element of the VCSEL array 3 to project the projection light 6 having a predetermined measurement pattern over the entire measurement area including the object 7 as shown in FIG. do.

As the measurement pattern, a predetermined projection pattern such as a black and white gray code pattern is projected by controlling the lighting and extinguishing (on/off) of the light emitting elements of the VCSEL array 3 . In FIG. 37, the optical system 4 for making the light of the VCSEL array 3 linear is provided independently of the light source section, but it may be included in the light source section.

The camera device 21 captures an image of the above measurement area at a fixed position and angle such that the projection center 41 of the projection light 6 projected onto the object by the projection device 2 is substantially at the center of the imaging area 40 .

The camera device 21 has a lens 210 and an imaging device 211 as a light receiving optical system. As the imaging device 211, for example, a CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor) image sensor or the like can be used. Light incident on the camera device 21 forms an image on the imaging device 211 via the lens 210 and is photoelectrically converted. An image signal generated by photoelectric conversion in the imaging element 211 is supplied to the arithmetic processing section 320 of the control unit 300 .

A narrow-band filter that transmits the emission wavelength of the VCSEL array 3 may be used for the lens 210 . As a result, it is possible to suppress the influence of ambient light (interference light such as a fluorescent lamp) at the time of measurement, and to enable accurate measurement. A narrow band filter may be provided in front of the lens 210 . Also in this case, the same effect can be obtained.

The control unit 300 controls the projection of the pattern light for measurement by the projection device 2 and the imaging control by the camera device 21, and performs calculations such as three-dimensional measurement of the measurement target based on the information on the image captured by the camera device 21. process. Note that the control unit 310 may perform control for switching the pattern light for measurement projected by the projection device 2 to another pattern light. Further, the control unit 310 may control the output of calibration information that the arithmetic processing unit 320 uses to calculate the three-dimensional coordinates.

The arithmetic processing section 320 of the control unit 300 calculates (measures) three-dimensional coordinates corresponding to the three-dimensional shape of the object 7 or information about the three-dimensional coordinates based on the supplied information about the image. The arithmetic processing section 320 may output three-dimensional shape information indicating the calculated three-dimensional shape to an external device such as a personal computer device under the control of the control section 310 .

Note that FIG. 37 shows an example in which one set of measurement information acquisition units 20 is provided for the control unit 300 , but multiple sets of measurement information acquisition units 20 may be provided for the control unit 300 . Moreover, although FIG. 37 shows an example in which the measurement information acquisition unit 20 and the control unit 300 are provided independently, part or all of the control unit 300 may be included in the measurement information acquisition unit 20 .

Thus, by applying the movable device according to the embodiment to a measuring device, it is possible to accurately control the oscillation of the movable portion 101 and provide a measuring device capable of measuring with high accuracy.

<Robot>
Next, a robot to which the mobile device 13 according to the embodiment is applied will be described in detail with reference to FIG. 39 . FIG. 39 is a diagram showing a robot arm having multiple joints of the robot 70. As shown in FIG.

In FIG. 39, a robot arm 72, which is an articulated arm, has a hand portion 71 for picking an object 7, and the three-dimensional measuring device 1 is provided in the immediate vicinity of the hand portion 71. As shown in FIG. The robot arm 72 has a plurality of bendable joints, and changes the position and posture of the hand section 71 according to control.

The three-dimensional measurement apparatus 1 is provided so that the projection direction of light matches the direction in which the hand unit 71 faces, and measures the picking target of the hand unit 71 as the measurement target object 7 .

The robot 70 can measure the picking object 7 from a short distance by using the three-dimensional measuring device 1 provided on the robot arm 72 . Therefore, it is possible to improve the measurement accuracy as compared with the case where the picking object 7 is measured from a distance using a camera device or the like. For example, in the field of FA in various assembly lines in factories, a robot 70 having a robot arm 72 is used for inspecting and recognizing parts. By providing the robot 70 with the three-dimensional measuring device 1, it is possible to accurately inspect and recognize parts.

Also, if there is an invalid area in the captured image for distance measurement, the robot arm 72 is fed back to the robot arm 72, based on the image signal and the three-dimensional shape, the position and orientation information indicating the position and orientation at which complementary data can be obtained. As a result, the control of the robot arm 72 can be easily performed, and more highly accurate component inspection, recognition, or the like can be performed based on the data complemented measurement results.

Also, the relationship between the positions and orientations of the measuring device and the object to be measured may be changed relative to each other. For this reason, although the three-dimensional measuring device 1 is provided on the robot arm 72, the measurement target may be provided on the robot arm 72 and its position and orientation may be changed.

When the three-dimensional measuring device 1 is mounted on the robot arm 72 and three-dimensionally measures an object to be measured, a distance of 200 mm from the three-dimensional measuring device 1 is suitable. Therefore, the divergence angle of the output light beam of the pattern light (line light) needs to be 21 degrees or more, which is achieved in the present embodiment.

By applying the movable device according to the embodiment to a robot in this way, it is possible to accurately control the swinging motion of the movable part 101, and to provide a robot that can be controlled with high accuracy.

<Optical writing device>
Next, an optical writing device to which the movable device of this embodiment is applied will be described in detail with reference to FIGS. 40 and 41. FIG.

FIG. 40 shows an example of an image forming apparatus in which the optical writing device 600 is incorporated. The optical writing device 600 is an example of an electronic device, and is an example of a modeling device from the viewpoint of modeling on a recording medium. Also, FIG. 41 is a schematic diagram of an example of an optical writing device.

As shown in FIG. 40, the optical writing device 600 is used as a constituent member of an image forming apparatus typified by a laser printer 650 having a printer function using laser light. In the image forming apparatus, the optical writing device 600 performs optical writing on the photosensitive drum by optically scanning the photosensitive drum, which is the surface to be scanned 15, with one or more laser beams.

As shown in FIG. 41, in an optical writing device 600, laser light from a light source device 12 such as a laser element passes through an imaging optical system 601 such as a collimator lens, and then passes through a movable device 13 having a reflecting surface 14. Axially or biaxially deflected. Then, the laser beam deflected by the movable device 13 passes through the scanning optical system 602 consisting of the first lens 602a, the second lens 602b, and the reflecting movable portion 602c, and passes through the surface to be scanned 15 (for example, the photosensitive drum or the photosensitive paper). ) to perform optical writing. The scanning optical system 602 forms a spot-like light beam on the surface 15 to be scanned. Also, the movable device 13 having the light source device 12 and the reflecting surface 14 is driven based on the control of the control device 11 .

Thus, the optical writing device 600 can be used as a component of an image forming apparatus having a printer function using laser light. In addition, by making the scanning optical system different so that optical scanning can be performed not only in one axial direction but also in two axial directions, a laser label device or the like that prints by deflecting a laser beam onto a thermal medium, performing optical scanning, and heating the media. can be used as a component of the image forming apparatus.

The movable device 13 having the reflecting surface 14 applied to the optical writing device consumes less power for driving than a rotating polygonal mirror using a polygon mirror or the like, so it contributes to power saving of the optical writing device. Advantageous. In addition, since wind noise when the movable device 13 vibrates is smaller than that of the rotating polygon mirror, it is advantageous for improving the quietness of the optical writing device. The optical writing device requires an overwhelmingly smaller installation space than the rotary polygon mirror, and the amount of heat generated by the movable device 13 is also very small. be.

As described above, by applying the movable device 13 of the embodiment to an optical writing device, it is possible to accurately control the oscillation of the movable portion 101 and provide an optical writing device capable of optical scanning with high accuracy.

[Image projection device]
Next, an image projection device to which the movable device of this embodiment is applied will be described in detail with reference to FIGS. 42 and 43. FIG.

FIG. 42 is a schematic diagram of an embodiment of an automobile 400 equipped with a head-up display device 500, which is an example of an image projection device. Also, FIG. 43 is a schematic diagram of an example of the head-up display device 500 . Automobile 400 is an example of a mobile object.

An image projection device is a device that projects an image by optical scanning, such as a head-up display device.

As shown in FIG. 42, the head-up display device 500 is installed near the windshield (windshield 401 etc.) of the automobile 400, for example. The projection light L emitted from the head-up display device 500 is reflected by the windshield 401 and travels toward the observer (driver 402) who is the user. Accordingly, the driver 402 can visually recognize the image or the like projected by the head-up display device 500 as a virtual image. A combiner may be installed on the inner wall surface of the windshield so that the user can visually recognize the virtual image by projected light reflected by the combiner.

As shown in FIG. 43, head-up display device 500 emits laser light from red, green, and blue laser light sources 501R, 501G, and 501B. The emitted laser light passes through an incident optical system composed of collimator lenses 502, 503, and 504 provided for each laser light source, two dichroic mirrors 505 and 506, and a light amount adjustment section 507, It is deflected by a movable device 13 having a reflective surface 14 . The deflected laser light passes through a projection optical system composed of a free-form surface mirror 509, an intermediate screen 510, and a projection mirror 511, and is projected onto the screen. In the head-up display device 500, the laser light sources 501R, 501G and 501B, the collimator lenses 502, 503 and 504, and the dichroic mirrors 505 and 506 are unitized as a light source unit 530 by an optical housing.

The head-up display device 500 projects the intermediate image displayed on the intermediate screen 510 onto the windshield 401 of the automobile 400 so that the driver 402 can visually recognize the intermediate image as a virtual image.

Color laser beams emitted from laser light sources 501R, 501G, and 501B are collimated by collimator lenses 502, 503, and 504, respectively, and combined by two dichroic mirrors 505 and 506, respectively. Each of the dichroic mirrors 505 and 506 is an example of a combiner. The combined laser light is two-dimensionally scanned by the movable device 13 having the reflecting surface 14 after the light amount is adjusted by the light amount adjusting unit 507 . The projection light L that has been two-dimensionally scanned by the movable device 13 is reflected by the free-form surface mirror 509 and corrected for distortion, and then converged on the intermediate screen 510 to display an intermediate image. The intermediate screen 510 is composed of a microlens array in which microlenses are two-dimensionally arranged, and magnifies the projection light L incident on the intermediate screen 510 in microlens units.

The movable device 13 reciprocates the reflecting surface 14 in two axial directions, and two-dimensionally scans the projection light L incident on the reflecting surface 14 . The drive control of this movable device 13 is performed in synchronization with the light emission timings of the laser light sources 501R, 501G, and 501B.

The head-up display device 500 has been described above as an example of the image projection device, but the image projection device may be any device that projects an image by performing optical scanning with the movable device 13 having the reflecting surface 14. . For example, a projector that is placed on a desk or the like and projects an image onto a display screen, is mounted on a mounting member that is worn on the head of an observer, etc., and projects onto a reflective transmission screen that the mounting member has, or uses the eyeball as a screen. The same can be applied to a head-mounted display device or the like that projects an image.

In addition, the image projection device is used not only for vehicles and mounting members, but also for mobile objects such as aircraft, ships, and mobile robots, or working robots that operate objects to be driven such as manipulators without moving from the spot. It may be mounted on a non-moving object.

In this way, by applying the movable device 13 of the embodiment to an image projection device, it is possible to accurately control the rocking movement of the movable portion 101 and provide an image projection device capable of high-precision optical scanning. In addition, the projection range of the image projection device can be kept constant at a desired dimension.

[Laser headlamp]
Next, a laser headlamp 50 in which the movable device of this embodiment is applied to a headlight of an automobile will be described with reference to FIG. 44 . FIG. 44 is a schematic diagram illustrating an example of the configuration of the laser headlamp 50. As shown in FIG.

The laser headlamp 50 has a control device 11 , a light source device 12 b , a movable device 13 having a reflecting surface 14 , a mirror 51 and a transparent plate 52 .

The light source device 12b is a light source that emits blue laser light. Light emitted from the light source device 12 b enters the movable device 13 and is reflected by the reflecting surface 14 . The movable device 13 moves the reflecting surface in the XY directions based on a signal from the control device 11, and two-dimensionally scans the blue laser light from the light source device 12b in the XY directions.

The scanning light from the movable device 13 is reflected by the mirror 51 and enters the transparent plate 52 . The transparent plate 52 is coated with a yellow phosphor on its front or back surface. As the blue laser light from the mirror 51 passes through the yellow phosphor coating on the transparent plate 52, it changes to white within the legal headlight color range. As a result, the front of the automobile is illuminated with white light from the transparent plate 52 .

The scanning light from the movable device 13 undergoes predetermined scattering when passing through the phosphor of the transparent plate 52 . This alleviates the glare in the illuminated object in front of the vehicle.

When applying the movable device 13 to a headlight of a car, the colors of the light source device 12b and the phosphor are not limited to blue and yellow, respectively. For example, the light source device 12b may be near-ultraviolet rays, and the transparent plate 52 may be coated with a uniform mixture of the three primary colors of light, namely blue, green, and red phosphors. Even in this case, the light passing through the transparent plate 52 can be converted into white light, and the front of the automobile can be illuminated with white light.

Thus, by applying the movable device 13 of the embodiment to a laser headlamp, the oscillation of the movable portion 101 can be accurately controlled, and a laser headlamp capable of optical scanning with high accuracy can be provided.

[Head-mounted display]
Next, a head mounted display 60 to which the movable device of the present embodiment is applied will be described with reference to FIGS. 45 and 46. FIG. Here, the head-mounted display 60 is a head-mounted display that can be worn on a person's head, and can have a shape similar to eyeglasses, for example. The head-mounted display will hereinafter be abbreviated as HMD.

FIG. 45 is a perspective view illustrating the appearance of the HMD 60. FIG. In FIG. 45, the HMD 60 is composed of a front 60a and a temple 60b, which are provided approximately symmetrically in pairs on the left and right sides. The front 60a can be composed of, for example, a light guide plate 61, and the optical system, control device, and the like can be incorporated in the temple 60b.

FIG. 46 is a diagram partially illustrating the configuration of the HMD 60. As shown in FIG. Although FIG. 46 illustrates the configuration for the left eye, the HMD 60 has the same configuration for the right eye.

The HMD 60 has a control device 11 , a light source unit 530 , a light quantity adjusting section 507 , a movable device 13 having a reflecting surface 14 , a light guide plate 61 and a half mirror 62 .

The light source unit 530 unitizes the laser light sources 501R, 501G and 501B, the collimator lenses 502, 503 and 504, and the dichroic mirrors 505 and 506 with an optical housing as described above. In the light source unit 530, the three-color laser beams from the laser light sources 501R, 501G, and 501B are synthesized by the dichroic mirrors 505 and 506. Combined parallel light is emitted from the light source unit 530 .

The light from the light source unit 530 is incident on the movable device 13 after the light amount is adjusted by the light amount adjusting section 507 . The movable device 13 moves the reflecting surface 14 in the XY directions based on a signal from the control device 11 and two-dimensionally scans the light from the light source unit 530 . The driving control of the movable device 13 is performed in synchronization with the light emission timing of the laser light sources 501R, 501G, and 501B, and a color image is formed by scanning light.

Scanning light from the movable device 13 enters the light guide plate 61 . The light guide plate 61 guides the scanning light to the half mirror 62 while reflecting it on the inner wall surface. The light guide plate 61 is made of resin or the like that is transparent to the wavelength of the scanning light.

The half mirror 62 reflects the light from the light guide plate 61 toward the back side of the HMD 60 and emits the light toward the eyes of the wearer 63 of the HMD 60 . The half mirror 62 has, for example, a free curved surface shape. An image of the scanning light is reflected by the half mirror 62 and formed on the retina of the wearer 63 . Alternatively, an image is formed on the retina of the wearer 63 by the reflection on the half mirror 62 and the lens effect of the crystalline lens in the eyeball. Further, the spatial distortion of the image is corrected by the reflection on the half mirror 62 . The wearer 63 can observe an image formed by light scanned in the XY directions.

Since 62 is a half mirror, the wearer 63 observes an image of light from the outside and an image of scanning light superimposed. By providing a mirror in place of the half mirror 62, the light from the outside may be eliminated and only the image by the scanning light may be observed.

Thus, by applying the movable device 13 of the embodiment to a head-mounted display, it is possible to accurately control the rocking movement of the movable portion 101 and provide a head-mounted display capable of optical scanning with high accuracy.

[Packaging]
Next, the packaging of the movable device of this embodiment will be described with reference to FIG. 47 .

Figure 47 is a schematic diagram of an example of a packaged mobile device.

As shown in FIG. 47, the movable device 13 is attached to an attachment member 802 arranged inside a package member 801, and is packaged by covering a part of the package member with a transparent member 803 and sealing it. be. Furthermore, the inside of the package is sealed with an inert gas such as nitrogen. As a result, deterioration due to oxidation of the movable device 13 is suppressed, and durability against environmental changes such as temperature is improved.

Although examples of embodiments of the present invention have been described above, the present invention is not limited to such specific embodiments, and various modifications can be made within the scope of the invention described in the claims. Transformation and change are possible.

In the above-described embodiment, the configuration in which the movable portion is provided with the reflecting surface was exemplified, but the configuration is not limited to this, and the movable portion includes a diffraction grating, a photodiode, a heater (for example, a heater using SiN), Other optical elements, such as a light source (eg, a surface-emitting laser), or both reflective surfaces and other optical elements, can also be provided.

1 Three-dimensional measuring device (an example of measuring device)
10 Optical scanning system 11 Control device 12, 12b Light source device 13 Movable device 14 Reflecting surface 15 Surface to be scanned 25 Light source device driver 26 Movable device driver 30 Control unit 31 Drive signal output unit 50 Laser headlamp 51 Mirror 52 Transparent plate 60 Head mount Display 60a Front 60b Temple 61 Light guide plate 62 Half mirror 63 Wearer 70 Robot 101 Movable part 102 Movable part base 110a First drive beam 110b Second drive beam 111a First torsion beam 111b Second torsion beam 112a First piezoelectric drive part 112b second piezoelectric driving portion 120 first supporting portions 130a, 130b pair of driving portions 131a to 131f third piezoelectric driving portions 132a to 132f fourth piezoelectric driving portion 140 second supporting portion 150 electrode connecting portions 160, 160A, 160B, 160C; 160D, 160E, 160F, 160G, 160H First to fourth strain resistors 160a, 160Aa, 160Ba, 160Ca, 160Da, 160Ea, 160Fa, 160Ga, 160Ha First strain resistors 160b, 160Ab, 160Bb, 160Cb, 160Db, 160Eb , 160 Fb , 160Gb, 160Hb Second strain resistors 160c, 160Ac, 160Bc, 160Cc, 160Dc, 160Ec, 160Fc, 160Gc, 160Hc 0Hd 4th strain resistor 201, 301 Lower electrodes 202, 302 Piezoelectric units 203, 303 Upper electrode 330 Detection unit 331 Drive control unit 500 Head-up display device (an example of an image projection device)
600 Optical writing device (an example of an electronic device, an example of a molding device)
700 laser radar device (an example of a distance measuring device, an example of an object recognition device)
701 automobile (an example of a vehicle, an example of a moving body)
Da, Db, Dc, Dd Distance Ex Second oscillation axis Ey First oscillation axis Pd1 to Pd8 Connection terminals V1, V2 Voltage i Constant current

Japanese Patent No. 5441533

Claims (20)

a movable part that swings around at least a first swing axis;
a first torsion beam having one end connected to the movable part;
a second torsion beam provided on the opposite side of the first torsion beam across the movable portion and having one end connected to the movable portion;
a first drive beam connected to the other end side of the first torsion beam;
a second drive beam connected to the other end side of the second torsion beam;
a first support that cantilevers each of the first drive beam and the second drive beam;
a first strain resistor disposed on the first drive beam;
a second strain resistor disposed on the first drive beam;
a third strain resistor disposed on the second drive beam;
a fourth strain resistor disposed on the second drive beam;
a detection unit that outputs rocking angle information of the movable part about the first rocking axis based on the resistance values of the first to fourth strain resistors;
The first strain resistance is arranged closer to the free end of the first drive beam than the first swing axis,
The third strain resistance is arranged closer to the free end of the second drive beam than the first swing axis,
The second strain resistance is arranged on either the fixed end side or the free end side of the first drive beam with respect to the first swing axis,
The fourth strain resistance is arranged on either the fixed end side or the free end side of the second drive beam relative to the first swing axis,
the distance between the first strain resistor and the first swing axis is longer than the distance between the second strain resistor and the first swing axis;
The movable device, wherein the distance between the third strain resistor and the first swing axis is longer than the distance between the fourth strain resistor and the first swing axis. Each of the first to fourth strain resistors is an N-type piezoresistor,
2. The movable device of claim 1, wherein each of the first drive beam and the second drive beam comprises a P-type silicon substrate. Each of the first to fourth strain resistors is a P-type piezoresistor,
2. The movable device of claim 1, wherein each of the first drive beam and the second drive beam comprises an N-type silicon substrate. a pair of drive units for rocking the movable unit around a second rocking axis that intersects with the first rocking axis;
The movable device according to any one of claims 1 to 3, wherein each longitudinal direction of said first to said fourth strain resistors is a direction along said first swing axis. Having a second support portion that supports the pair of driving portions,
each of the pair of drive units has a plurality of beams and a connecting portion that connects the plurality of beams by folding back;
one end of each of the pair of drive portions is connected to the first support portion;
The movable device according to claim 4, wherein the other end of each of the pair of driving parts is connected to the second supporting part. The movable device according to any one of claims 1 to 5, wherein the longitudinal direction of each of the first and second torsion beams is parallel to the <100> direction. 6. A movable device according to claim 4 or 5, wherein the longitudinal direction of each of said first and said second torsion beams is parallel to the <110> direction. A movable device according to any one of claims 1 to 7;
a light source;
A distance measuring device that measures a distance to an object by deflecting light emitted from the light source, irradiating the light onto an object, and detecting reflected light reflected from the object. A measuring device comprising the movable device according to any one of claims 1 to 7. A robot comprising the measuring device according to claim 9 . An electronic device comprising the movable device according to any one of claims 1 to 7. A modeling apparatus, comprising the movable device according to any one of claims 1 to 7. A movable device according to any one of claims 1 to 7;
a light source;
An image projection device that deflects and projects light emitted from the light source. A plurality of the light sources are provided,
wherein the plurality of light sources emit light of different wavelengths;
further comprising a synthesizing unit that synthesizes the plurality of lights emitted from the plurality of light sources;
14. The image projection apparatus according to claim 13, wherein the combined light in said combining unit is deflected and projected. A head-up display comprising the movable device according to any one of claims 1 to 7. A laser headlamp comprising a mobile device according to any one of claims 1 to 7. A head mounted display comprising the movable device according to any one of claims 1 to 7. A movable device according to any one of claims 1 to 7;
a light source;
An object recognition device that recognizes an object by deflecting light emitted from the light source, illuminating the object with the light, and detecting reflected light reflected from the object. A vehicle comprising at least one of a distance measuring device according to claim 8, a head-up display according to claim 15 and a laser headlamp according to claim 16. A moving object having at least one of the distance measuring device according to claim 8, the head-up display according to claim 15, and the laser headlamp according to claim 16.

Images