Movable devices, distance measuring devices, measuring devices, robots, electronic devices, molding devices, image projection devices, head-up displays, laser headlamps, head-mounted displays, object recognition devices, vehicles and moving objects

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

[Technical Field]

[0001] The present invention relates to a movable device, a distance measuring device, a measuring device, a robot, an electronic device, a molding device, an image projection device, a head-up display, a laser headlamp, a head-mounted display, an object recognition device, a vehicle, and a moving object. [Background technology]

[0002] Conventionally, movable devices using MEMS (Micro Electro Mechanical Systems) devices manufactured by microfabrication of silicon or glass have been known. Movable devices are used for a variety of purposes, such as in-vehicle laser radar devices, head-up displays, and head-mounted displays.

[0003] As a movable device, a device has been disclosed which has a pair of torsion beams supported at both ends and which support the movable part so that it can oscillate, and a pair of strain resistors arranged in positions symmetrical about the oscillation axis of the movable part, and which can detect the oscillation angle of the movable part using a Wheatstone bridge circuit consisting of the pair of strain resistors and a pair of external fixed elements (see, for example, Patent Document 1). Summary of the Invention [Problem to be solved by the invention]

[0004] A movable device capable of detecting the swing angle of a movable part is required to have excellent accuracy in detecting the swing angle of the movable part.

[0005] An object of the present invention is to provide a movable device that has excellent accuracy in detecting the swing angle of a movable part. [Means for solving the problem]

[0006] A movable device according to one aspect of the present invention includes a movable section that swings around at least a first swing axis, a first torsion beam having one end connected to the movable section, a second torsion beam that is provided on the opposite side of the first torsion beam across the movable section and has one end connected to the movable section, a first drive beam that connects to the other end of the first torsion beam, a second drive beam that connects to the other end of the second torsion beam, a first support section that cantilever-supports 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 first drive beam, a third strain resistor arranged on the second drive beam, a fourth strain resistor arranged on the second drive beam, and resistors that cantilever each of the first to fourth strain beams. and a detection unit that outputs information about the oscillation angle of the movable part around the first oscillation axis based on the resistance values ​​of the strain resistors, wherein the first strain resistor is arranged closer to the free end of the first drive beam than the first oscillation axis, the third strain resistor is arranged closer to the free end of the second drive beam than the first oscillation axis, the second strain resistor is arranged on either the fixed end side or the free end side of the first drive beam than the first oscillation axis, and the fourth strain resistor is arranged on either the fixed end side or the free end side of the second drive beam than the first oscillation axis, and the distance between the first strain resistor and the first oscillation axis is longer than the distance between the second strain resistor and the first oscillation axis. The resistance change rate of each strain resistor caused by stress is approximately the same. The distance between the third strain resistor and the first oscillation axis is longer than the distance between the fourth strain resistor and the first oscillation axis. The resistance change rate of each strain resistor caused by stress is made to be approximately the same. . [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a movable device that has excellent accuracy in detecting the swing angle of the movable part. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a plan view illustrating a movable device according to an embodiment. [Figure 2] 2 is an end view of the movable device of FIG. 1 along the second oscillation axis. [Figure 3] 3 is an end view of the movable device taken along the line III-III in FIG. 1. [Figure 4] 3 is a plan view of a detailed configuration example of the periphery of first to fourth strain-sensitive resistors according to the first embodiment. FIG. [Figure 5] FIG. 2 is a diagram illustrating a bridge circuit having first to fourth strain resistors. [Figure 6] FIG. 10 is a plan view of a detailed configuration example of the periphery of first to fourth strain-sensitive resistors according to a first modified example. [Figure 7] FIG. 7 is a cross-sectional view taken along the line VII-VII in FIG. 6. [Figure 8] FIG. 10 is a diagram illustrating an example of a bridge circuit including first to fourth strain resistors according to a first modified example. [Figure 9] FIG. 10 is a plan view of a detailed configuration example of the periphery of first to fourth strain-sensitive resistors according to a second modified example. [Figure 10] FIG. 10 is a cross-sectional view taken along the line XX in FIG. 9. [Figure 11] FIG. 10 is a diagram illustrating an example of a bridge circuit including first to fourth strain resistors according to a second modified example. [Figure 12] FIG. 11 is a plan view of a detailed configuration example of the periphery of first to fourth strain-sensitive resistors according to a third modified example. [Figure 13] FIG. 13 is a cross-sectional view taken along the line XIII-XIII in FIG. [Figure 14] FIG. 10 is a diagram illustrating an example of a bridge circuit including first to fourth strain resistors according to a third modified example. [Figure 15] FIG. 11 is a plan view of a detailed configuration example around first to fourth strain-sensitive resistors according to a fourth modified example. [Figure 16] FIG. 16 is a cross-sectional view taken along the line XVI-XVI in FIG. [Figure 17] FIG. 10 is a diagram illustrating an example of a bridge circuit including first to fourth strain resistors according to a fourth modified example. [Figure 18] FIG. 13 is a plan view of a detailed configuration example of the periphery of first to fourth strain-sensitive resistors according to a fifth modified example. [Figure 19] FIG. 19 is a cross-sectional view taken along the line XIX-XIX in FIG. 18. [Figure 20] FIG. 10 is a diagram illustrating an example of a bridge circuit including first to fourth strain resistors according to a fifth modified example. [Figure 21] FIG. 13 is a plan view of a detailed configuration example of the periphery of first to fourth strain-sensitive resistors according to a sixth modified example. [Figure 22] FIG. 22 is a cross-sectional view taken along the line XXII-XXII in FIG. 21. [Figure 23] FIG. 13 is a diagram illustrating an example of a bridge circuit including first to fourth strain resistors according to a sixth modified example. [Figure 24] FIG. 13 is a plan view of a detailed configuration example of the periphery of first to fourth strain-sensitive resistors according to a seventh modified example. [Figure 25] FIG. 25 is a cross-sectional view taken along the line XXV-XXV in FIG. 24. [Figure 26] FIG. 13 is a diagram illustrating an example of a bridge circuit including first to fourth strain resistors according to a seventh modified example. [Figure 27] FIG. 13 is a plan view of a detailed configuration example of the periphery of first to fourth strain resistors according to an eighth modified example. [Figure 28] FIG. 28 is a cross-sectional view taken along the line XXVIII-XXVIII in FIG. 27. [Figure 29] FIG. 13 is a diagram illustrating an example of a bridge circuit including first to fourth strain resistors according to an eighth modified example. [Figure 30] FIG. 1 is a schematic diagram of an example optical scanning system. [Figure 31] FIG. 1 is a diagram illustrating a hardware configuration of an example of an optical scanning system. [Figure 32] FIG. 2 is a functional block diagram of an example of a control device. [Figure 33] 10 is a flowchart of an example of processing related to the optical scanning system. [Figure 34] FIG. 1 is a schematic diagram of an example of an automobile equipped with a laser radar device. [Figure 35] FIG. 10 is a schematic diagram of another example of a vehicle equipped with a laser radar device. [Figure 36] FIG. 1 is a schematic diagram of an example of a laser radar device. [Figure 37] FIG. 1 is a block diagram of a three-dimensional measuring apparatus. [Figure 38] FIG. 10 is a diagram illustrating an example of a state in which a measurement pattern is projected onto an object. [Figure 39] FIG. 1 is a diagram showing a robot arm having multiple joints of a robot. [Figure 40] FIG. 1 is a schematic diagram of an example of an image forming apparatus equipped with an optical writing device. [Figure 41] FIG. 1 is a schematic diagram of an example of an optical writing device. [Figure 42] FIG. 1 is a schematic diagram of an example of an automobile equipped with a head-up display device. [Figure 43] FIG. 1 is a schematic diagram of an example of a head-up display device. [Figure 44] 1 is a schematic diagram of an example of a laser headlamp. [Figure 45] FIG. 1 is a perspective view of an example of the appearance of a head-mounted display. [Figure 46] FIG. 1 is a diagram illustrating a partial configuration of a head-mounted display. [Figure 47] 1 is a schematic diagram of an example of a packaged movable device. DETAILED DESCRIPTION OF THE INVENTION

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following describes the preferred embodiments of the present invention with reference to the accompanying drawings. In the drawings, the same components are designated by the same reference numerals, and redundant explanations will be omitted where appropriate.

[0010] In the following description of the embodiments, rotation, swinging, and movement are synonymous. Among the directions indicated by arrows, the stacking direction of each layer in the piezoelectric drive unit, etc., is the Z direction, and the directions perpendicular to the Z direction in a plane perpendicular to the Z direction are the X and Y directions. Planar view refers to viewing an object from the Z direction.

[0011] Additionally, the direction in which the arrow points in the X direction will be referred to as the +X direction, and the direction opposite to the +X direction will be referred to as the -X direction, the direction in which the arrow points in the Y direction will be referred to as the +Y direction, and the direction opposite to the +Y direction will be referred to as the -Y direction, and the direction in which the arrow points in the Z direction will be referred to as the +Z direction, and the direction opposite to the +Z direction will be referred to 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.

[0012] [Embodiment] <Configuration example of the movable device 13> The configuration of a movable device 13 according to a first embodiment will be described with reference to Figures 1 to 3. Figure 1 is a plan view illustrating the movable device 13. Figure 2 is an end view of the movable device 13 taken along the second axis in Figure 1. Figure 3 is an end view of the movable device 13 taken along the III-III cutting line in Figure 1.

[0013] 1, movable device 13 includes movable section 101, first torsion beam 111a, second torsion beam 111b, first actuation beam 110a, second actuation beam 110b, first support section 120, first strain resistor 160a, and second strain resistor 160b. Movable device 13 also includes third strain resistor 160c, fourth strain resistor 160d, a pair of actuation sections 130a and 130b, second support section 140, electrode connection section 150, and control device 11.

[0014] The movable device 13 is an optical deflection device that can scan light incident on the movable part 101 in both the X and Y directions by swinging the movable part 101 around a first swing axis Ey and a second swing axis Ex. 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 that is substantially perpendicular to the Y axis.

[0015] Movable part 101 has reflecting surface 14 that reflects incident light. One end of first torsion beam 111a is connected to movable part 101. Second torsion beam 111b is provided on the opposite side of first torsion beam 111a across movable part 101, and one end of second torsion beam 111b is connected to movable part 101.

[0016] The first drive beam 110a is connected to the other end of the first torsion beam 111a, and the second drive beam 110b is connected to the other end of the second torsion beam 111b. The first support section 120 cantilevers each of the first drive beam 110a and the second drive beam 110b. The first support section 120 is a rectangular frame-shaped support body formed to surround the movable section 101. The end of each of the cantilevered first drive beam 110a and second drive beam 110b on the -X direction side is a free end, and the end on the +X direction side is a fixed end.

[0017] The first actuation beam 110a has a first piezoelectric actuation part 112a and is actuated in response to a drive voltage applied to the first piezoelectric actuation part 112a. The second actuation beam 110b has a second piezoelectric actuation part 112b and is actuated in response to a drive voltage applied to the second piezoelectric actuation part 112b.

[0018] When the first actuation beam 110a and the second actuation beam 110b are actuated, the first torsion beam 111a and the second torsion beam 111b twist with the first oscillation axis Ey as the torsion center axis, and the movable part 101 swings around the first oscillation axis Ey.

[0019] The first strain resistor 160a and the second strain resistor 160b are respectively disposed on the first actuation beam 110a, and the third strain resistor 160c and the fourth strain resistor 160d are respectively disposed on the second actuation beam 110b.

[0020] The first strain resistor 160a and the second strain resistor 160b are resistors whose resistance values ​​change in response to stress applied to the first actuation beam 110a due to torsion of the first torsion beam 111a. The third strain resistor 160c and the fourth strain resistor 160d are resistors whose resistance values ​​change in response to stress applied to the second actuation beam 110b due to torsion of the second torsion beam 111b. The longitudinal direction of each of the first strain resistor 160a, the second strain resistor 160b, the third strain resistor 160c, and the fourth strain resistor 160d is along the first oscillation axis Ey.

[0021] In the following description, the first strain resistor 160a, the second strain resistor 160b, the third strain resistor 160c, and the fourth strain resistor 160d will be collectively referred to as the first to fourth strain resistors 160 unless they are to be particularly distinguished from one another.

[0022] The first to fourth strain resistors 160 are, for example, piezoelectric elements that convert a force applied to a piezoelectric body into a voltage, or convert a voltage into a force, utilizing the piezoelectric effect. In this embodiment, the first to fourth strain resistors 160 are made of a semiconductor material.

[0023] Each of the pair of drive units 130a and 130b has a plurality of beams 135 and a connecting portion 136 that folds back and connects the plurality of beams 135. The second support unit 140 supports the pair of drive units 130a and 130b. One end of each of the pair of drive units 130a and 130b is connected to the first support unit 120, and the other end of each of the pair of drive units 130a and 130b is connected to the second support unit 140.

[0024] The connection point between driver 130a and first support 120 and the connection point between driver 130b and first support 120 are point symmetrical with respect to the center of reflecting surface 14. The connection point between driver 130a and second support 140 and the connection point between driver 130b and second support 140 are point symmetrical with respect to the center of reflecting surface 14.

[0025] The driving unit 130a has third piezoelectric driving units 131a to 131f and is driven in response to driving voltages applied to the third piezoelectric driving units 131a to 131f. The driving unit 130b has fourth piezoelectric driving units 132a to 132f and is driven in response to driving voltages applied to the fourth piezoelectric driving units 132a to 132f.

[0026] When the pair of drive units 130a and 130b are driven, the movable unit 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 unit 120 swing together around the second swing axis Ex.

[0027] The second support portion 140 is a rectangular frame-shaped support formed to surround the movable portion 101, the first torsion beam 111a, the second torsion beam 111b, the first actuation beam 110a, the second actuation beam 110b, the first support portion 120, and the pair of actuation portions 130a and 130b.

[0028] The electrode connection portion 150 is formed on the +Z side surface of the second support portion 140 and is electrically connected to the first piezoelectric driving portion 112a, the second piezoelectric driving portion 112b, the third piezoelectric driving portions 131a to 131f and the fourth piezoelectric driving portions 132a to 132f via electrode wiring such as aluminum (Al).

[0029] The control device 11 has a detection unit 330 and a drive control unit 331. The control device 11 applies a drive voltage via the electrode connection unit 150 to each of the first piezoelectric drive unit 112a, the second piezoelectric drive unit 112b, the third piezoelectric drive units 131a to 131f, and the fourth piezoelectric drive units 132a to 132f.

[0030] The detection unit 330 outputs oscillation angle information of the movable part 101 around the first oscillation axis Ey 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 is configured with an operational amplifier and the like. The oscillation angle information is information indicating the oscillation angle of the movable part 101 around the first oscillation axis Ey, or information related to the oscillation angle of the movable part 101 around the first oscillation axis Ey.

[0031] The drive control unit 331 controls the driving of the first actuation beam 110a, the second actuation beam 110b, and the pair of actuation units 130a and 130b. The drive control unit 331 also controls the drive voltage based on the oscillation angle information output from the detection unit 330, thereby controlling the oscillation angle of the movable unit 101 around the first oscillation axis Ey.

[0032] The movable device 13 is formed, for example, by etching a single SOI (Silicon On Insulator) substrate. On the formed substrate, the reflecting surface 14, the first piezoelectric driving unit 112a, the second piezoelectric driving unit 112b, the third piezoelectric driving units 131a to 131f, the fourth piezoelectric driving units 132a to 132f, the electrode connection unit 150, etc. are integrally formed. Note that these components may be formed after the SOI substrate is formed, or may be formed during the formation of the SOI substrate.

[0033] 2, the SOI substrate on which the movable device 13 is formed includes a silicon support layer 161 made of single crystal silicon (Si), a silicon oxide layer 162 formed on the silicon support layer 161 (on the +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 referred to as a BOX (Buried Oxide) layer.

[0034] Since the silicon active layer 163 has a smaller thickness in the Z direction than in the X or Y direction, a member formed only from the silicon active layer 163 functions as an elastic part having elasticity.

[0035] The SOI substrate does not necessarily have to be flat, and may have curvature, etc. Furthermore, the material used to form the movable device 13 is not limited to an SOI substrate, as long as it can be integrally formed by etching or the like and can be made partially elastic.

[0036] The movable section 101 includes, for example, a circular movable section base 102 and a reflecting surface 14 formed on the +Z side surface of the movable section base 102. The movable section base 102 includes, for example, a silicon active layer 163. The reflecting surface 14 includes, for example, a metal thin film containing aluminum, gold, silver, or the like.

[0037] The third piezoelectric driving units 131a to 131f and the fourth piezoelectric driving units 132a to 132f are configured by laminating a lower electrode 201, a piezoelectric unit 202, and an upper electrode 203 in this order on the +Z side surface of the silicon active layer 163, which is the elastic unit. The upper electrode 203 and the lower electrode 201 contain, for example, gold (Au) or platinum (Pt). The piezoelectric unit 202 contains, for example, PZT (lead zirconate titanate), which is a piezoelectric material.

[0038] A driving voltage is applied to the lower electrode 201, and the upper electrode 203 is grounded (GND). The upper electrode 203 or the lower electrode 201 may each be directly connected to the electrode connection portion 150, or may be indirectly connected by connecting the electrodes together, etc. Alternatively, the lower electrode 201 may be grounded (GND), and a driving voltage may be applied to the upper electrode 203.

[0039] A rib 103 for reinforcing the movable part is formed on the -Z side surface of the movable part base 102. The rib 103 includes, for example, a silicon support layer 161 and a silicon oxide layer 162, and suppresses distortion of the reflecting surface 14 caused by movement. However, the rib 103 is not an essential component.

[0040] 3, second torsion beam 111b includes silicon active layer 163. Second piezoelectric driver 112b is configured by laminating lower electrode 301, piezoelectric section 302, and upper electrode 303 in this order on the +Z side surface of silicon active layer 163, which is the elastic section. Upper electrode 303 and lower electrode 301 contain, for example, gold (Au) or platinum (Pt). Piezoelectric section 302 contains, for example, PZT (lead zirconate titanate), which is a piezoelectric material.

[0041] A driving 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 each be directly connected to the electrode connection part 150, or may be indirectly connected by connecting the electrodes together, etc. Alternatively, the lower electrode 301 may be grounded (GND), and a driving voltage may be applied to the upper electrode 303.

[0042] In this embodiment, an example has been described in which the piezoelectric portion 202 is formed only on one surface (the +Z side surface) of the silicon active layer 163, which is the elastic portion, but it may also be provided on another surface (for example, the -Z side surface) of the elastic portion, or on both one surface and the other surface of the elastic portion.

[0043] Furthermore, as long as the movable part 101 can be driven around the first oscillation axis Ey and the second oscillation axis Ex, the shapes of the components are not limited to those shown in this embodiment. For example, the first torsion beam 111a and the second torsion beam 111b, and the first actuation beam 110a and the second actuation beam 110b may have a curvature.

[0044] Furthermore, an insulating layer made of a silicon oxide film may be formed on at least one of the +Z side surfaces of the upper electrodes 303 of the first actuation beam 110a and the second actuation beam 110b, the +Z side surface of the first support member 120, the +Z side surfaces of the upper electrodes 203 of the pair of actuation members 130a and 130b, and the +Z side surface of the second support member 140.

[0045] Electrode wiring is provided on the insulating layer, and only at connection spots where the upper electrode 203, upper electrode 303, lower electrode 201, and lower electrode 301 are connected to the electrode wiring, the insulating layer is partially removed or no insulating layer is formed as openings. This configuration increases the design freedom of the first actuation beam 110a, second actuation beam 110b, pair of actuation units 130a and 130b, and electrode wiring, and further suppresses short circuits due to contact between electrodes. The silicon oxide film also functions as an anti-reflection material.

[0046] <Control by the control device 11> The control by the control device 11 for driving the first drive beam 110a and the second drive beam 110b of the movable device 13 will be briefly described.

[0047] 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, thereby exhibiting the so-called inverse piezoelectric effect. The first drive beam 110a and the second drive beam 110b oscillate the movable portion 101 by utilizing the inverse piezoelectric effect.

[0048] The angle formed by the XY plane and the reflecting surface 14 when the reflecting surface 14 of the movable part 101 is tilted in the +Z direction or the -Z direction with respect to the XY plane is called the deflection angle. The +Z direction is a positive deflection angle, and the -Z direction is a negative deflection angle.

[0049] When a driving voltage is applied in parallel to the piezoelectric portions 302 via the upper electrode 303 and the lower electrode 301, each piezoelectric portion 302 is deformed. This deformation of the piezoelectric portions 302 causes the first piezoelectric driving portion 112a and the second piezoelectric driving portion 112b to bend and deform. As a result, a driving force about the first oscillation axis Ey acts on the movable portion 101 via the torsion of the first torsion beam 111a and the second torsion beam 111b, causing the movable portion 101 to oscillate about the first oscillation axis Ey. The driving voltages applied to the first actuation beam 110a and the second actuation beam 110b are controlled by a drive control portion 331.

[0050] By applying a drive voltage of a predetermined sinusoidal waveform in parallel to the first piezoelectric drive unit 112a and the second piezoelectric drive unit 112b by the drive control unit 331, the movable unit 101 can be oscillated around the first oscillation axis Ey in accordance with the period of the drive voltage.

[0051] For example, when the frequency of the drive voltage is set to approximately 20 kHz, which is similar to the resonant frequency of first torsion beam 111a and second torsion beam 111b, the movable part 101 can be made to resonate and oscillate at approximately 20 kHz by utilizing the mechanical resonance caused by the torsion of first torsion beam 111a and second torsion beam 111b.

[0052] [First embodiment] <Detailed configuration example of the first to fourth strain resistors 160 and their surroundings> 4 is a plan view illustrating a detailed configuration around the first to fourth strain resistors 160. As shown in FIG. 4, the first strain resistor 160a is arranged closer to the free end (-X direction side) of the first actuation beam 110a than the first oscillation axis Ey. The third strain resistor 160c is arranged closer to the free end (-X direction side) of the second actuation beam 110b than the first oscillation axis Ey. The second strain resistor 160b is arranged closer to the fixed end (+X direction side) of the first actuation beam 110a than the first oscillation axis Ey. The fourth strain resistor 160d is arranged closer to the fixed end (+X direction side) of the second actuation beam 110b than the first oscillation axis Ey. The first to fourth strain resistors 160 form a Wheatstone bridge circuit.

[0053] The distance Da is the distance between the first strain resistor 160a and the first oscillation axis Ey. The distance Db is the distance between the second strain resistor 160b and the first oscillation axis Ey. The distance Dc is the distance between the third strain resistor 160c and the first oscillation axis Ey. The distance Dd is the distance between the fourth strain resistor 160d and the first oscillation axis Ey.

[0054] In this embodiment, distances Da, Db, Dc, and Dd are adjusted so that the rate of change in the resistance value of each of first to fourth strain resistors 160 due to the torsion of first torsion beam 111a and second torsion beam 111b is approximately equal. As a result of this adjustment, distance Da is longer than distance Db, and distance Dc is longer than distance Dd.

[0055] <Functions of the 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, stress is applied to the first drive beam 110a due to the torsion of the first torsion beam 111a, and stress is applied to the second drive beam 110b due to the torsion of the second torsion beam 111b.

[0056] In the X direction, the first actuation beam 110a and the second actuation beam 110b are subjected to compressive stress on the free end side and tensile stress on the fixed end side. The stress value on the free end side is smaller than that on the fixed end side, and the stress value increases toward the rounded fillet side. Meanwhile, in the Y direction, tensile stress is applied to the free end side and compressive stress on the fixed end side, and the stress value on the free end side is smaller than that 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.

[0057] When the distance Da and the distance Dc are approximately equal, the stresses applied to the first actuation beam 110a and the second actuation beam 110b are equal at the positions of the first strain resistor 160a and the third strain resistor 160c. Similarly, when the distance Db and the distance Dd are approximately equal, the stresses applied to the first actuation beam 110a and the second actuation beam 110b are equal at the positions of the second strain resistor 160b and the fourth strain resistor 160d.

[0058] 5 is a diagram illustrating a bridge circuit having first to fourth strain resistors 160. When a constant current i is applied to the Wheatstone bridge circuit, the resistance value R1 of first strain resistor 160a and third strain resistor 160c is expressed as R0+ΔR1, and the resistance value R2 of second strain resistor 160b and fourth strain resistor 160d is expressed as R0+ΔR2. Here, R0 represents the resistance value of each of the first to fourth strain resistors 160 when no stress is applied.

[0059] The voltage signal ΔV output from the Wheatstone bridge circuit is expressed by the following equation (1) according to Kirchhoff's law: ΔV=V1-V2={(R0+ΔR1) 2 -(R0+ΔR2) 2} / (4×R0+2×ΔR2+2×ΔR1)×i=(ΔR1 / R0-ΔR2 / R0)×R0×i / 2 ···(1)

[0060] The rate of change in strain resistance ΔR / R0 when a predetermined stress is applied is expressed by the following equation (2), taking into account quadratic terms. ΔR / R0≒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 represent the strain resistance coefficients, respectively.

[0061] The stresses applied to the first strain resistor 160a and the third strain resistor 160c are respectively represented as σa x , σa y , σa xy The stress applied to the second strain resistor 160b and the fourth strain resistor 160d is σb x , σb y , σb xy Let's say.

[0062] Substituting equation (2) into equation (1) and rearranging it, we obtain the following equation (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×π'112×(σa x ×σa y -σb x ×σb y )+π'122×(σa y 2 -σb y 2 )+π'166×(σaxy 2 -σb xy 2 )}×R0×i (3)

[0063] In the case of a cantilever beam, if the first to fourth strain resistors 160 are arranged symmetrically around the first oscillation axis Ey, which corresponds to the torsion central axis of the first torsion beam 111a and the second torsion beam 111b, the stress varies at each position, and the influence of the quadratic term cannot be ignored. As a result, the relationship between the oscillation angle of the movable part 101 and the oscillation angle information output by the detection unit 330 is no longer linear. However, if the stress is small, the quadratic term becomes negligible, and the relationship between the oscillation angle of the movable part 101 and the oscillation angle information output by the detection unit 330 becomes approximately linear.

[0064] The order of the strain resistance coefficient is the following value, so when the stress is several tens of MPa (10 8 ) or more, it cannot be ignored. In other words, the first-order term is 10 -10 x10 8 =10 -2 order, and the quadratic term is 10 -19 x10 16 =10 -3 It is an order of magnitude different, but it is still at a level that cannot be ignored.

[0065] 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 oscillation axis Ey, and the first strain resistor 160a and the third strain resistor 160c are arranged on the fixed end side with respect to the first oscillation axis Ey. Furthermore, the distances Da and Dc are made longer than the distances Db and Dd, and the distances Da, Db, Dc, and Dd are adjusted so that the rates of resistance change caused by stress are approximately the same. As a result, the relationship between the oscillation angle of the movable part 101 and the voltage signal ΔV output from the Wheatstone bridge circuit becomes approximately linear, and the relationship between the oscillation angle of the movable part 101 and the voltage signal ΔV can be expressed by a simple linear equation.

[0066] <Effects of the first to fourth strain resistors 160> Next, the effects of the first to fourth strain-sensitive resistors 160 will be described.

[0067] A conventional movable device using a MEMS device has been disclosed that has a pair of torsion beams that are supported at both ends and support a movable part so that it can oscillate, and a pair of strain resistors that are positioned symmetrically around the oscillation axis of the movable part, and that can detect the oscillation angle of the movable part using a Wheatstone bridge circuit composed of the pair of strain resistors and a pair of external fixed elements.

[0068] However, in a structure in which the drive beam is cantilevered, the magnitude of the stress applied to the drive beam in response to the torsion of the torsion beam is not symmetrical with respect to the oscillation axis of the movable part. Therefore, if the strain resistors are arranged symmetrically with the oscillation axis of the movable part as the center of symmetry, the relationship between the oscillation angle of the movable part and the voltage signal from the Wheatstone bridge circuit will not be linear, which may result in a decrease in the accuracy of detecting the oscillation angle.

[0069] In the movable device 13 according to this embodiment, the first strain resistor 160a is arranged closer to the free end of the first actuation beam 110a than the first oscillation axis Ey, the third strain resistor 160c is arranged closer to the free end of the second actuation beam 110b than the first oscillation axis Ey, the second strain resistor 160b is arranged closer to the fixed end of the first actuation beam 110a than the first oscillation axis Ey, and the fourth strain resistor 160d is arranged closer to the fixed end of the second actuation beam 110b than the first oscillation axis Ey. Furthermore, the distance Da between the first strain resistor 160a and the first oscillation axis Ey is longer than the distance Db between the second strain resistor 160b and the first oscillation axis Ey, and the distance Dc between the third strain resistor 160c and the first oscillation axis Ey is longer than the distance Dd between the fourth strain resistor 160d and the first oscillation axis Ey.

[0070] With the above configuration, the rate of change of the resistance values ​​of the first to fourth strain resistors 160 becomes approximately equal, and therefore the relationship between the oscillation angle of the movable part 101 and the voltage signal ΔV output from the Wheatstone bridge circuit becomes approximately linear, making it possible to express the relationship between the oscillation angle of the movable part 101 and the voltage signal ΔV by a linear equation. As a result, in this embodiment, the oscillation angle of the movable part 101 can be detected with high accuracy, making it easy to control the oscillation angle of the movable part 101 and enabling high-precision control. As a result, in this embodiment, it is possible to provide a movable device 13 that has excellent accuracy in detecting the oscillation angle of the movable part 101.

[0071] Furthermore, in this embodiment, a pair of drivers 130a and 130b are provided that swing the movable part 101 around a second oscillation axis Ex that intersects with the first oscillation axis Ey, and the longitudinal directions of the first to fourth strain resistors 160 (first to fourth strain resistors) are along the first oscillation axis Ey. With this configuration, the movable device 13 can swing the movable part 101 around two axes, the first oscillation axis Ey and the second oscillation axis Ex, and can scan the light incident on the reflecting surface 14 of the movable part 101 in two axial directions.

[0072] Furthermore, in this embodiment, the movable device 13 has a second support portion 140 that supports the pair of drive portions 130a and 130b, and each of the pair of drive portions 130a and 130b has a plurality of beam portions 135 and a connection portion 136 that folds back and connects the plurality of beam portions 135. One end of each of the pair of drive portions 130a and 130b is connected to the first support portion 120, and the other end of each of the pair of drive portions 130a and 130b 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 at a large swing angle.

[0073] However, the pair of drive units 130a and 130b and the second support unit 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 units 130a and 130b and the second support unit 140, the movable device 13 can achieve the effect of excellent accuracy in detecting the swing angle of the movable unit 101.

[0074] In this embodiment, the first to fourth strain resistors 160 are piezoelectric elements made of semiconductor material. While it is conceivable to use PZT (lead zirconate titanate) as the material for the first torsion beams 111a and the second torsion beams 111b, the stress associated with the torsion of the first torsion beams 111a and the second torsion beams 111b is large. For this reason, if strain resistors made of PZT (lead zirconate titanate) are used, the stress may cause the strain resistors to peel off from the silicon substrate. In this embodiment, the first to fourth strain resistors 160 are made of semiconductor material, and the first to fourth strain resistors 160 are formed as diffusion layers, so such peeling does not occur.

[0075] In this embodiment, the configuration in which the distance Da is approximately equal to the distance Dc and the distance Db is approximately equal to the distance Dd has been exemplified, but the present invention is not limited to this. In the first to fourth strain-sensitive resistors 160, as long as the resistance change rates in response to the stress applied to the first actuation beam 110a and the second actuation beam 110b are approximately equal, the distance Da is not necessarily equal to the distance Dc, and the distance Db is not necessarily equal to the distance Dd.

[0076] In addition, in the present embodiment, the configuration in which the second strain resistor 160b is arranged closer to the fixed end of the first actuation beam 110a than the first oscillation axis Ey and the fourth strain resistor 160d is arranged closer to the fixed end of the second actuation beam 110b than the first oscillation axis Ey has been exemplified, but the present invention 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 may be arranged closer to the free end of the first actuation beam 110a than the first oscillation axis Ey and the fourth strain resistor 160d may be arranged closer to the free end of the second actuation beam 110b than the first oscillation axis Ey.

[0077] <Modification> The movable device according to the embodiment can be modified in various ways. Each of the modified examples will be described below. Note that the same components as those of the movable device 13 according to the embodiment described above will be assigned the same reference numerals, and redundant explanations will be omitted as appropriate.

[0078] (First Modification) Fig. 6 is a plan view illustrating a detailed configuration around first to fourth strain resistors 160A according to the first modification. Fig. 7 is a cross-sectional view taken along line VII-VII in Fig. 6. Fig. 8 is a diagram illustrating a bridge circuit including first to fourth strain resistors 160A.

[0079] In this modification, the longitudinal directions of first torsion beam 111a and second torsion beam 111b in silicon (Si) with a crystal plane (001) are substantially parallel to first oscillation axis Ey. <110> In this case, first to fourth strain resistors 160A, which are P-type piezoresistors, are arranged so that their longitudinal directions are oriented in approximately the same direction as the longitudinal directions of first torsion beam 111a and second torsion beam 111b. In other words, the longitudinal directions of first torsion beam 111a and second torsion beam 111b are <110> It may be a P-type resistor in relation to an N-type silicon substrate.

[0080] 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. The first strain resistor 160Aa and the third strain resistor 160Ab are disposed on the first actuation beam 110a, and the second strain resistor 160Ac and the fourth strain resistor 160Ad are disposed on the second actuation beam 110b.

[0081] 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 set to be equal to or lower than the minimum potential applied to the first to fourth strain resistors 160A, and the N-well potential is set to be equal to or higher than the difference between the maximum voltage applied to the first to fourth strain resistors 160A and the forward voltage Vf of the parasitic PN diode.

[0082] The strain resistance coefficients of first to fourth strain resistors 160A can be set to the largest when the longitudinal direction of first torsion beam 111a and second torsion beam 111b are arranged so that they are approximately parallel to the longitudinal direction of first torsion beam 111a and second torsion beam 111b. However, even if the angle is slightly off, up to about ±30 degrees, the sensitivity of the strain resistance coefficients of first to fourth strain resistors 160A can be ensured to a certain extent, so first to fourth strain resistors 160A can be used.

[0083] The contact portions connecting the metal wiring to the first to fourth strain resistors 160A or the silicon substrate are diffusion layers with higher impurity concentrations than the first to fourth strain resistors 160A or the silicon substrate. This configuration improves the contact with the metal wiring. Note that 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 any step. This also applies to FIGS. 12 to 14 and 18 to 20 shown below.

[0084] 6 and 7, connection terminals Pd5 and Pd7 are connection terminals that take on an NW potential. Generally, connection terminals Pd5 and Pd7 are at the maximum potential. Connection terminals Pd6 and Pd8 are connection terminals that take on a P-type substrate potential. Generally, connection terminals Pd5 and Pd7 are at the minimum potential, and most of them are at the GND potential. All of connection terminals Pd1 to Pd8 are made of metal material.

[0085] In FIG. 8, a circuit 81 shows a Wheatstone bridge circuit when a constant voltage is applied, and a circuit 82 shows a Wheatstone bridge circuit when a constant current is applied.

[0086] The first to fourth strain resistors 160A have the same functions and effects as the first to fourth strain resistors 160.

[0087] (Second Modification) Fig. 9 is a plan view illustrating a detailed configuration around first to fourth strain resistors 160B according to the second modification. Fig. 10 is a cross-sectional view taken along line XX in Fig. 9. Fig. 11 is a diagram illustrating a bridge circuit including first to fourth strain resistors 160B.

[0088] In this modification, the crystal axes of the first torsion beams 111a and the second torsion beams 111b in silicon with a crystal plane (001) are <110> In this case, first to fourth strain resistors 160B, which are N-type piezoresistors, are arranged so that their longitudinal directions form approximately 45 degrees with the longitudinal directions of first torsion beam 111a and second torsion beam 111b. They may also be N-type resistors with respect to the silicon of the P-type substrate. In this case, the potential of the P-type substrate will be equal to or lower than the minimum potential applied to first to fourth strain resistors 160B.

[0089] 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. The first strain resistor 160Ba and the third strain resistor 160Bb are arranged on the first actuation beam 110a, and the second strain resistor 160Bc and the fourth strain resistor 160Bd are arranged on the second actuation beam 110b.

[0090] The strain resistance coefficients of first to fourth strain resistors 160B can be set to the largest when first to fourth strain resistors 160B are arranged so that their longitudinal directions form approximately 45 degrees with the longitudinal directions of first torsion beam 111a and second torsion beam 111b. However, even if the angle is slightly off by up to about ±15 degrees, the sensitivity of the strain resistance coefficients of first to fourth strain resistors 160B can be ensured to a certain extent, so first to fourth strain resistors 160B can still be used.

[0091] 9 and 10, Pd6 and Pd8 are connection terminals that take on the P-type substrate potential. In general, the connection terminals Pd4, Pd6 and Pd8 are at the GND potential.

[0092] In FIG. 11, a circuit 83 shows a Wheatstone bridge circuit when a constant voltage is applied, and a circuit 84 shows a Wheatstone bridge circuit when a constant current is applied.

[0093] The first to fourth strain resistors 160B have the same functions and effects as the first to fourth strain resistors 160.

[0094] (Third Modification) Fig. 12 is a plan view illustrating a detailed configuration around first to fourth strain resistors 160C according to the third modification. Fig. 13 is a cross-sectional view taken along line XIII-XIII in Fig. 12. Fig. 14 is a diagram illustrating a bridge circuit including first to fourth strain resistors 160C.

[0095] In this modification, the crystal axes of the first torsion beams 111a and the second torsion beams 111b in silicon with a crystal plane (001) are <100> In this case, first to fourth strain resistors 160C, which are N-type piezoresistors, are arranged so that their longitudinal directions are oriented in approximately the same direction as the longitudinal directions of first torsion beam 111a and second torsion beam 111b. In other words, the longitudinal directions of first torsion beam 111a and second torsion beam 111b are <100> It may be an N-type resistor with respect 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.

[0096] 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. The first strain resistor 160Ca and the third strain resistor 160Cb are arranged on the first actuation beam 110a, and the second strain resistor 160Cc and the fourth strain resistor 160Cd are arranged on the second actuation beam 110b.

[0097] The strain resistance coefficients of first to fourth strain resistors 160C can be set to the largest when first torsion beam 111a and second torsion beam 111b are arranged so that their longitudinal directions are approximately parallel to the longitudinal directions of first torsion beam 111a and second torsion beam 111b, respectively. However, even if the angle is slightly off, up to about ±15 degrees, the sensitivity of the strain resistance coefficients of first to fourth strain resistors 160C can be ensured to a certain extent, so first to fourth strain resistors 160C can be used.

[0098] 12 and 13, Pd6 and Pd8 are connection terminals that take on the P-type substrate potential. In general, the connection terminals Pd4, Pd6 and Pd8 are at the GND potential.

[0099] In FIG. 14, a circuit 85 shows a Wheatstone bridge circuit when a constant voltage is applied, and a circuit 86 shows a Wheatstone bridge circuit when a constant current is applied.

[0100] The first to fourth strain resistors 160C have the same functions and effects as the first to fourth strain resistors 160.

[0101] (Fourth Modification) Fig. 15 is a plan view illustrating a detailed configuration around first to fourth strain resistors 160D according to the fourth modification. Fig. 16 is a cross-sectional view taken along line XVI-XVI in Fig. 15. Fig. 17 is a diagram illustrating a bridge circuit including first to fourth strain resistors 160D.

[0102] In this modification, the crystal axes of the first torsion beams 111a and the second torsion beams 111b in silicon with a crystal plane (001) are <100> In this case, first to fourth strain resistors 160D, which are P-type piezoresistors, are arranged so that their longitudinal directions form approximately 45 degrees with the longitudinal directions of first torsion beam 111a and second torsion beam 111b. They may also be P-type resistors with respect to the silicon of the N-type substrate. In this case, the potential of the N-type substrate becomes equal to or greater than the maximum potential applied to first to fourth strain resistors 160D.

[0103] An N-well may be formed in the P-type silicon and a P-type resistor may be formed in the N-well. In this case, the potential of the P-type substrate becomes equal to or less than the minimum potential applied to the first to fourth strain resistors 160D, and the N-well potential becomes equal to or greater than the difference between the maximum voltage applied to the first to fourth strain resistors 160D and the forward voltage Vf of the parasitic PN diode.

[0104] 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. The first strain resistor 160Da and the third strain resistor 160Db are arranged on the first actuation beam 110a, and the second strain resistor 160Dc and the fourth strain resistor 160Dd are arranged on the second actuation beam 110b.

[0105] The strain resistance coefficients of first to fourth strain resistors 160D can be set to the largest when first to fourth strain resistors 160D are arranged so that their respective longitudinal directions form approximately 45 degrees with the longitudinal directions of first torsion beam 111a and second torsion beam 111b. However, even if the angle is slightly off, up to about ±30 degrees, the sensitivity of the strain resistance coefficients of first to fourth strain resistors 160D can be ensured to a certain extent, so first to fourth strain resistors 160D can be used.

[0106] 15 and 16, Pd5 and Pd7 are connection terminals that assume the NW potential. Generally, connection terminals Pd5 and Pd7 assume the maximum potential. Pd6 and Pd8 are connection terminals that assume the potential of the P-type substrate. Generally, connection terminals Pd4, Pd6, and Pd8 assume the minimum potential, and are often at the GND potential.

[0107] In FIG. 17, a circuit 87 shows a Wheatstone bridge circuit when a constant voltage is applied, and a circuit 88 shows a Wheatstone bridge circuit when a constant current is applied.

[0108] The first to fourth strain resistors 160D have the same functions and effects as the first to fourth strain resistors 160.

[0109] (Fifth to eighth modified examples) Fig. 18 is a plan view illustrating a detailed configuration around first to fourth strain resistors 160E according to a fifth modified example. Fig. 19 is a cross-sectional view taken along line XIX-XIX in Fig. 18. Fig. 20 is a diagram of an example bridge circuit including first to fourth strain resistors E.

[0110] Fig. 21 is a plan view illustrating a detailed configuration around first to fourth strain resistors 160F according to a sixth modified example. Fig. 22 is a cross-sectional view taken along line XXII-XXII in Fig. 21. Fig. 23 is a diagram illustrating a bridge circuit including first to fourth strain resistors F.

[0111] Fig. 24 is a plan view illustrating a detailed configuration around first to fourth strain resistors 160G according to a seventh modification. Fig. 25 is a cross-sectional view taken along line XXV-XXV in Fig. 24. Fig. 26 is a diagram illustrating a bridge circuit including first to fourth strain resistors G.

[0112] Fig. 27 is a plan view illustrating a detailed configuration around first to fourth strain resistors 160H according to an eighth modification. Fig. 28 is a cross-sectional view taken along line XXVIII-XXVIII in Fig. 27. Fig. 29 is a diagram illustrating a bridge circuit including first to fourth strain resistors H.

[0113] While the first to fourth modified examples use a P-type substrate, the fifth to eighth modified examples use an N-type substrate. The effects of the first to fourth strain-sensitive resistors 160E, 160F, 160G, and 160H in the fifth to eighth modified examples are similar to those of the first to fourth strain-sensitive resistors 160.

[0114] [Other Preferred Embodiments] The movable device 13 according to the above-described embodiment can be applied to various systems and devices. In the following, examples of application of the movable device 13 to various systems and devices will be described.

[0115] <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 Fig. 30 to Fig. 33. Fig. 30 shows a schematic diagram of an example of an optical scanning system. As shown in Fig. 30, the optical scanning system 10 is a system that optically scans a scanned surface 15 by deflecting light irradiated from a light source device 12 using a reflecting surface 14 of a movable device 13 under the control of a control device 11.

[0116] The optical scanning system 10 comprises a control device 11, a light source device 12, and a movable device 13 having a reflecting surface 14.

[0117] The control device 11 is, for example, an electronic circuit unit including a CPU (Central Processing Unit) and an FPGA (Field-Programmable Gate Array), etc. The movable device 13 is, for example, an MEMS device having a reflective surface 14 that is movable.

[0118] The light source device 12 is, for example, a laser device that emits a laser beam. The scanned surface 15 is, for example, a screen.

[0119] Control device 11 generates control commands for light source device 12 and movable device 13 based on the acquired optical scanning information, and outputs drive signals to light source device 12 and movable device 13 based on the control commands. Light source device 12 emits light based on the input drive signal. Movable device 13 rotationally vibrates reflective surface 14 in at least one axial direction or two axial directions based on the input drive signal.

[0120] As a result, for example, by controlling the control device 11 based on image information, which is an example of optical scanning information, the reflecting surface 14 of the movable device 13 is rotated and vibrated back and forth in two axial directions within a predetermined range, and as a result, the irradiated light from the light source device 12 incident on the reflecting surface 14 is deflected around a certain axis to perform optical scanning, thereby making it possible to project any image onto the scanned surface 15. Details of the movable device of this embodiment and details of the control by the control device will be described later.

[0121] Next, a hardware configuration of an example of the optical scanning system 10 will be described with reference to Fig. 31. Fig. 31 is a hardware configuration diagram of an example of the optical scanning system 10. 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. Of 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.

[0122] The CPU 20 is a computing device that reads out programs and data from a storage device such as the ROM 22 onto the RAM 21, executes processing, and realizes the overall control and functions of the control device 11.

[0123] The RAM 21 is a volatile storage device that temporarily stores programs and data.

[0124] The ROM 22 is a non-volatile 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.

[0125] The FPGA 23 is a circuit that outputs control signals suitable for the light source device driver 25 and the movable device driver 26 in accordance with the processing of the CPU 20 .

[0126] The external I / F 24 is, for example, an interface with an external device or a network. Examples of external devices include higher-level devices such as a PC (Personal Computer), and storage devices such as a USB memory, an SD card, a CD, a DVD, a HDD, and an SSD. Examples of networks include a CAN (Controller Area Network) or a LAN (Local Area Network) in an automobile, the Internet, etc. The external I / F 24 may have any configuration as long as it enables connection or communication with an external device, and an external I / F 24 may be provided for each external device.

[0127] 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 in accordance with an input control signal.

[0128] The movable device driver 26 is an electric circuit that outputs a drive signal such as a drive voltage to the movable device 13 in accordance with the input control signal.

[0129] In the control device 11, the CPU 20 acquires optical scanning information from an external device or a network via the external I / F 24. Note that any configuration may be used as long as the CPU 20 can acquire the optical scanning information, and the optical scanning information may be stored in the ROM 22 or FPGA 23 in the control device 11, or a new storage device such as an SSD may be provided in the control device 11 and the optical scanning information may be stored in the storage device.

[0130] Here, the optical scanning information is information indicating how to optically scan the scanned surface 15. For example, when an image is displayed by optical scanning, the optical scanning information is image data. Also, for example, when optical writing is performed by optical scanning, the optical scanning information is writing data indicating the writing order and writing locations. Additionally, for example, when object recognition is performed by optical scanning, the optical scanning information is irradiation data indicating the timing and irradiation range of irradiating light for object recognition.

[0131] The control device 11 can realize the following functional configuration by instructions from the CPU 20 and the hardware configuration shown in FIG.

[0132] Next, the functional configuration of the control device 11 of the optical scanning system 10 will be described with reference to Fig. 32. Fig. 32 is a functional block diagram of an example of the control device 11 of the optical scanning system.

[0133] As shown in FIG. 32, the control device 11 has a control section 30 and a drive signal output section 31 as functions.

[0134] The control unit 30 is realized by, for example, the CPU 20, the FPGA 23, etc., and acquires optical scanning information from an external device, converts the optical scanning information into a control signal, and outputs it to the drive signal output unit 31. For example, the control unit 30 acquires image data from an external device, etc. as optical scanning information, generates a control signal from the image data by performing predetermined processing, and outputs it 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.

[0135] The drive signal is a signal for controlling the drive of the light source device 12 or the movable device 13. For example, in the light source device 12, the drive signal is a drive voltage that controls the timing and intensity of irradiation of the light source. Also, in the movable device 13, the drive signal is a drive voltage that controls the timing and range of movement of the reflective surface 14 of the movable device 13.

[0136] Next, the process of optically scanning the surface 15 to be scanned by the optical scanning system 10 will be described with reference to Fig. 33. Fig. 33 is a flowchart showing an example of the process related to the optical scanning system.

[0137] In step S11, the control unit 30 acquires optical scanning information from an external device or the like. In step S12, the control unit 30 generates a control signal from the acquired optical scanning information and outputs the control signal to the drive signal output unit 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 emits light based on the input drive signal. Furthermore, the movable device 13 rotationally 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 any direction and optical scanning is performed.

[0138] In the optical scanning system 10, one control device 11 has the devices and functions to control the light source device 12 and the movable device 13, but the control device for the light source device and the control device for the movable device may be provided separately.

[0139] In the optical scanning system 10, the functions of the control unit 30 for the light source device 12 and the movable device 13 and the drive signal output unit 31 are provided in one control device 11, but these functions may exist separately, for example, a drive signal output device having the drive signal output unit 31 may be provided separately from the control device 11 having the control unit 30. Note that, in the optical scanning system 10, the movable device 13 having the reflective surface 14 and the control device 11 may form an optical deflection system that performs optical deflection.

[0140] In this way, by applying the movable device 13 of the embodiment to an optical scanning system, it is possible to provide an optical scanning system that can precisely control the oscillation of the movable part 101 and perform optical scanning with high precision.

[0141] <Distance measuring device> Next, a distance measurement device to which the movable device of the present embodiment is applied will be described in detail with reference to Figures 34 to 36. The distance measurement device is a device that measures the distance to an object in a target direction, and is, for example, a laser radar device.

[0142] Figures 34 and 35 are schematic diagrams of an automobile in which a laser radar device is mounted in a lamp unit that mounts the automobile's headlights, and Figure 36 is a schematic diagram of an example of a laser radar device.

[0143] 34 and 35, a laser radar device 700 is mounted on, for example, an automobile 701, and measures the distance to an object 702 by optically scanning the object in the target direction and receiving reflected light from the object 702 present in the target direction. The automobile 701 is an example of a vehicle, and an example of a moving body.

[0144] As shown in FIG. 36 , laser light emitted from light source device 12 passes through an incident optical system composed of a collimator lens 703, which converts divergent light into approximately parallel light, and a plane mirror 704, and is scanned in one or two axes by movable device 13 having a reflective surface 14. The light then passes through a projection lens 705 and other components of a projection optical system and is irradiated onto an object 702 in front of the device. The drive of light source device 12 and movable device 13 is controlled by control device 11. The reflected light reflected by object 702 is detected by a photodetector 709. That is, the reflected light passes through a condenser lens 706 and other components of an incident light detection and light receiving optical system and is received by an image sensor 707, which outputs a detection signal to a signal processing device 708. The signal processing device 708 performs predetermined processing, such as binarization and noise reduction, on the input detection signal and outputs the result to a distance measurement circuit 710.

[0145] The distance measurement circuit 710 recognizes the presence or absence of the target object 702 based on the time difference between when the light source device 12 emits laser light and when the laser light is received by the photodetector 709, or the phase difference between each pixel of the image sensor 707 that receives the light, and further calculates distance information from the target object 702.

[0146] The movable device 13 with the reflective surface 14 is less likely to break than a polygonal mirror and is small, making it possible to provide a highly durable and compact radar device. Such a laser radar device can be attached to, for example, a vehicle, an aircraft, a ship, a robot, etc., and can optically scan a predetermined area to determine the presence or absence of obstacles and the distance to the obstacles.

[0147] The above distance measuring device has been described as an example of a laser radar device 700, but the distance measuring device may be any device that performs optical scanning by controlling a movable device 13 having a reflective surface 14 with a control device 11, and measures the distance to the target object 702 by receiving reflected light with a photodetector, and is not limited to the above-mentioned embodiment.

[0148] For example, the laser radar device 700 can be similarly applied to biometric authentication that calculates object information such as shape from distance information obtained by optically scanning a hand or face and recognizes the target by referring to a record, a security sensor that recognizes an intruder by optically scanning a target range, and components 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.

[0149] In this way, by applying the movable device 13 of the embodiment to a distance measurement device, it is possible to provide a distance measurement device that can precisely control the oscillation of the movable part 101 and perform optical scanning with high precision. The measurement range of the distance measurement device can be maintained constant at a desired size.

[0150] <Measuring equipment> Next, a measurement 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. Here, a three-dimensional measurement device that performs three-dimensional measurement of an object using a pattern projection method is taken as an example of the measurement device. Fig. 37 is a block diagram showing an example of the configuration of the three-dimensional measurement 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.

[0151] As shown in FIG. 37, the three-dimensional measuring apparatus 1 includes a measurement information acquisition unit 20 and a control unit 300.

[0152] 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) 3, an optical system 4, and a movable device 13. By using the VCSEL array 3 as a light source, the light emission interval can be made finer and multiple light-focusing points can be formed.

[0153] The measurement information acquisition unit 20, under the control of the control unit 310 of the control unit 300, deflects light from multiple light-emitting elements included in the VCSEL array 3 using the movable device 13 and projects it onto an object in the measurement area. The control unit 310 controls the brightness and lighting timing of each light-emitting element of the VCSEL array 3, thereby projecting projection light 6 of a predetermined measurement pattern onto the entire measurement area including the object 7, as shown in FIG.

[0154] 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 shaping the light of the VCSEL array 3 into a line is provided independently of the light source unit, but it may also be included in the light source unit.

[0155] The camera device 21 captures an image of the measurement area at a fixed position and angle so that the projection center 41 of the projection light 6 projected onto the object by the projection device 2 is approximately at the center of the imaging area 40 .

[0156] The camera device 21 has a lens 210, which is a light receiving optical system, and an image sensor 211. The image sensor 211 may be, for example, a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) image sensor. Light incident on the camera device 21 is imaged on the image sensor 211 via the lens 210 and photoelectrically converted. An image signal generated by photoelectric conversion in the image sensor 211 is supplied to an arithmetic processing unit 320 of the control unit 300.

[0157] The lens 210 may be provided with a narrow-band filter that transmits the emission wavelength of the VCSEL array 3. This reduces the influence of ambient light (disturbing light from fluorescent lights, etc.) during measurement, enabling highly accurate measurement. A narrow-band filter may also be provided in front of the lens 210. In this case, the same effect can be obtained.

[0158] The control unit 300 controls the projection of the measurement pattern light by the projection device 2 and the imaging by the camera device 21, and performs arithmetic processing such as three-dimensional measurement of the measurement target based on information about the image captured by the camera device 21. The control unit 310 may also control switching of the measurement pattern light projected by the projection device 2 to another pattern light. The control unit 310 may also control the output of calibration information used by the arithmetic processing unit 320 to calculate three-dimensional coordinates.

[0159] Based on the information related to the supplied image, the arithmetic processing unit 320 of the control unit 300 calculates (measures) three-dimensional coordinates corresponding to the three-dimensional shape of the object 7 or information related to the three-dimensional coordinates. The arithmetic processing unit 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 unit 310.

[0160] 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. Also, while FIG. 37 shows an example in which the measurement information acquisition unit 20 and the control unit 300 are provided independently, some or all of the control unit 300 may be included in the measurement information acquisition unit 20.

[0161] In this way, by applying the movable device according to the embodiment to a measurement device, it is possible to provide a measurement device that can control the oscillation of the movable part 101 with high precision and is capable of performing measurements with high precision.

[0162] <Robot> Next, a robot to which the movable 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 of a robot 70 having multiple joints.

[0163] 39, a robot arm 72, which is an articulated arm, has a hand unit 71 for picking up an object 7, and a three-dimensional measuring device 1 is provided in close proximity to the hand unit 71. The robot arm 72 has a plurality of joints that can be bent, and changes the position and posture of the hand unit 71 according to control.

[0164] The three-dimensional measuring device 1 is installed so that the projection direction of light coincides with the direction in which the hand unit 71 faces, and measures the object to be picked up by the hand unit 71 as the object 7 to be measured.

[0165] The robot 70 can measure the object 7 to be picked from a short distance using the three-dimensional measuring device 1 provided on the robot arm 72. This allows for improved measurement accuracy compared to measuring the object 7 to be picked from a long distance using a camera device or the like. For example, in the field of factory automation (FA) in various assembly lines in factories, the robot 70 equipped with the robot arm 72 is used for the inspection and recognition of parts. By providing the three-dimensional measuring device 1 on the robot 70, the inspection and recognition of parts can be performed with high accuracy.

[0166] Furthermore, if an invalid area exists in the captured image for distance measurement, position and orientation information indicating the position and orientation at which complementary data can be acquired based on the image signal and three-dimensional shape is fed back to the robot arm 72. This makes it possible to easily control the robot arm 72, and more accurate component inspection or recognition can be performed based on the measurement results with complementary data.

[0167] Furthermore, it is only necessary to change the relative position and orientation of the measuring instrument and the measurement target. For this reason, although the three-dimensional measuring device 1 is provided on the robot arm 72, the measurement target may also be provided on the robot arm 72, and its position and orientation may be changed.

[0168] When the three-dimensional measuring device 1 is mounted on a robot arm 72 and an object to be measured is measured in three dimensions, a distance of 200 mm from the three-dimensional measuring device 1 is preferable. Therefore, the divergence angle of the emitted light beam of the pattern light (line light) needs to be 21 degrees or more, which is achieved in this embodiment.

[0169] By applying the movable device according to the embodiment to a robot in this manner, the swinging of the movable part 101 can be controlled with high precision, and a robot that can be controlled with high precision can be provided.

[0170] <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.

[0171] Fig. 40 shows an example of an image forming apparatus incorporating an optical writing device 600. The optical writing device 600 is an example of an electronic device and also an example of a modeling device from the viewpoint of modeling a recording medium. Fig. 41 is a schematic diagram of an example of the optical writing device.

[0172] 40, the optical writing device 600 is used as a component of an image forming apparatus such as a laser printer 650 having a laser light printer function. In the image forming apparatus, the optical writing device 600 optically writes on the photosensitive drum, which is the scanned surface 15, by optically scanning the photosensitive drum with one or more laser beams.

[0173] 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 is then deflected in one or two axial directions by a movable device 13 having a reflective surface 14. The laser light deflected by the movable device 13 then passes through a scanning optical system 602 consisting of a first lens 602a, a second lens 602b, and a reflective movable part 602c, and is irradiated onto a scanned surface 15 (e.g., a photosensitive drum or photosensitive paper) to perform optical writing. The scanning optical system 602 forms an image of the light beam in a spot shape on the scanned surface 15. The light source device 12 and the movable device 13 having the reflective surface 14 are driven under the control of a control device 11.

[0174] In this way, the optical writing device 600 can be used as a component of an image forming device having a laser printer function. Also, by changing the scanning optical system to enable optical scanning not only in one axis direction but also in two axes directions, the optical writing device 600 can be used as a component of an image forming device such as a laser label device that prints by deflecting and optically scanning a laser beam onto a thermal medium and heating it.

[0175] The movable device 13 having the reflective surface 14 used in the optical writing device described above consumes less power to drive than a rotating polygon mirror or the like, which is advantageous for reducing the power consumption of the optical writing device. In addition, the wind noise generated when the movable device 13 vibrates is smaller than that of a rotating polygon mirror, which is advantageous for improving the quietness of the optical writing device. The optical writing device requires significantly less installation space than a rotating polygon mirror, and the movable device 13 generates only a small amount of heat, making it easy to reduce the size, which is advantageous for reducing the size of the image forming device.

[0176] In this way, by applying the movable device 13 of the embodiment to an optical writing device, the oscillation of the movable part 101 can be controlled with high precision, and an optical writing device capable of optical scanning with high precision can be provided.

[0177] [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.

[0178] 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. Fig. 43 is a schematic diagram of an example of the head-up display device 500. The automobile 400 is an example of a moving body.

[0179] The image projection device is a device that projects an image by optical scanning, and is, for example, a head-up display device.

[0180] 42, the head-up display device 500 is installed near the windshield (windshield 401 or the like) of an automobile 400, for example. Projected light L emitted from the head-up display device 500 is reflected by the windshield 401 and directed toward an observer (driver 402) who is a user. This allows the driver 402 to view an image projected by the head-up display device 500 as a virtual image. Note that a combiner may be installed on the inner wall surface of the windshield, and the user may view a virtual image by the projected light reflected by the combiner.

[0181] 43 , in a head-up display device 500, laser beams are emitted from red, green, and blue laser light sources 501R, 501G, and 501B. The emitted laser beams pass through an incident optical system including collimator lenses 502, 503, and 504 provided for each laser light source, two dichroic mirrors 505 and 506, and a light amount adjuster 507, and are then deflected by a movable device 13 having a reflecting surface 14. The deflected laser beams then pass through a projection optical system including a free-form surface mirror 509, an intermediate screen 510, and a projection mirror 511, and are projected onto a 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 by an optical housing as a light source unit 530.

[0182] The head-up display device 500 projects an intermediate image displayed on an intermediate screen 510 onto a windshield 401 of an automobile 400, thereby allowing a driver 402 to visually recognize the intermediate image as a virtual image.

[0183] The color laser beams emitted from the laser light sources 501R, 501G, and 501B are converted into approximately parallel beams by collimator lenses 502, 503, and 504, respectively, and then combined by two dichroic mirrors 505 and 506. The dichroic mirrors 505 and 506 are each an example of a combining unit. The combined laser beam has its intensity adjusted by a light intensity adjusting unit 507, and then is two-dimensionally scanned by a movable device 13 having a reflecting surface 14. The projection light L two-dimensionally scanned by the movable device 13 is reflected by a free-form surface mirror 509, where distortion is corrected, and then focused on an intermediate screen 510 to display an intermediate image. The intermediate screen 510 is composed of a microlens array in which microlenses are arranged two-dimensionally, and the projection light L incident on the intermediate screen 510 is magnified by each microlens.

[0184] The movable device 13 reciprocates the reflective surface 14 in two axial directions, thereby two-dimensionally scanning the projection light L incident on the reflective surface 14. The drive control of this movable device 13 is performed in synchronization with the light emission timing of the laser light sources 501R, 501G, and 501B.

[0185] The above has described the head-up display device 500 as an example of an 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 reflective surface 14. For example, the present invention can be similarly applied to a projector that is placed on a desk or the like and projects an image onto a display screen, or a head-mounted display device that is mounted on a mounting member that is worn on the observer's head or the like and projects an image onto a reflective / transmissive screen that the mounting member has, or projects an image using the observer's eyeball as a screen.

[0186] Furthermore, the image projection device may be mounted not only on a vehicle or a mounting member, but also on a moving body such as an aircraft, a ship, or a mobile robot, or on a non-moving body such as a work robot that operates a driving object such as a manipulator without moving from its location.

[0187] In this way, by applying the movable device 13 of the embodiment to an image projection device, it is possible to provide an image projection device that can precisely control the swing of the movable part 101 and perform optical scanning with high precision. In addition, it is possible to maintain the projection range of the image projection device at a constant desired size.

[0188] [Laser headlamp] Next, a laser headlamp 50 in which the movable device of this embodiment is applied to an automobile headlight 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.

[0189] The laser headlamp 50 includes a control device 11, a light source device 12b, a movable device 13 having a reflective surface 14, a mirror 51, and a transparent plate 52.

[0190] Light source device 12b is a light source that emits blue laser light. The light emitted from light source device 12b is incident on movable device 13 and reflected by reflective surface 14. Movable device 13 moves the reflective surface in the X and Y directions based on a signal from control device 11, and performs two-dimensional scanning of the blue laser light from light source device 12b in the X and Y directions.

[0191] The scanning light from the movable device 13 is reflected by a mirror 51 and enters a transparent plate 52. The front or back surface of the transparent plate 52 is coated with a yellow phosphor. When the blue laser light from the mirror 51 passes through the yellow phosphor coating on the transparent plate 52, it changes to white, which is within the legal range for headlight colors. As a result, the front of the vehicle is illuminated with white light from the transparent plate 52.

[0192] The scanning light from the movable device 13 is scattered in a predetermined manner when passing through the phosphor of the transparent plate 52. This reduces glare on the illuminated object in front of the automobile.

[0193] When the movable device 13 is applied to an automobile headlight, 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, and the transparent plate 52 may be covered with a uniform mixture of phosphors of the three primary colors of light: blue, green, and red. Even in this case, the light passing through the transparent plate 52 can be converted to white, and the front of the automobile can be illuminated with white light.

[0194] In this way, by applying the movable device 13 of the embodiment to a laser headlamp, the swing of the movable part 101 can be controlled with high precision, and a laser headlamp capable of optical scanning with high precision can be provided.

[0195] [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 Figures 45 and 46. Here, the head-mounted display 60 is a head-mounted display that can be worn on a human head, and can have a shape similar to glasses, for example. The head-mounted display will be abbreviated as HMD hereinafter.

[0196] Fig. 45 is a perspective view illustrating an example of the appearance of the HMD 60. In Fig. 45, the HMD 60 is composed of a front 60a and temples 60b, which are provided in a pair on the left and right sides and are substantially symmetrical. The front 60a can be composed of, for example, a light guide plate 61, and the optical system, control device, etc. can be built into the temples 60b.

[0197] Fig. 46 is a diagram illustrating a portion of the configuration of the HMD 60. Note that Fig. 46 illustrates the configuration for the left eye, but the HMD 60 has a similar configuration for the right eye.

[0198] The HMD 60 includes a control device 11 , a light source unit 530 , a light amount adjusting section 507 , a movable device 13 having a reflecting surface 14 , a light guide plate 61 , and a half mirror 62 .

[0199] As described above, the light source unit 530 is a unit formed by combining the laser light sources 501R, 501G, and 501B, the collimator lenses 502, 503, and 504, and the dichroic mirrors 505 and 506 using an optical housing. In the light source unit 530, the three color laser beams from the laser light sources 501R, 501G, and 501B are combined by the dichroic mirrors 505 and 506. The light source unit 530 emits the combined parallel light.

[0200] The light from the light source unit 530 is adjusted in amount by the light amount adjusting section 507 and then enters the movable device 13. The movable device 13 moves the reflecting surface 14 in the X and Y directions based on a signal from the control device 11, and performs two-dimensional scanning with the light from the light source unit 530. The drive control of this 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 the scanning light.

[0201] The scanning light from the movable device 13 is incident on the light guide plate 61. The light guide plate 61 reflects the scanning light on its inner wall surface and guides it to the half mirror 62. The light guide plate 61 is made of a material such as a resin that is transparent to the wavelength of the scanning light.

[0202] The half mirror 62 reflects the light from the light guide plate 61 towards the back side of the HMD 60 and emits it in the direction of the eyes of a wearer 63 of the HMD 60. The half mirror 62 has, for example, a free-form surface shape. An image formed by the scanning light is formed on the retina of the wearer 63 by reflection from the half mirror 62. Alternatively, an image is formed on the retina of the wearer 63 by reflection from the half mirror 62 and the lens effect of the crystalline lens in the eyeball. Furthermore, spatial distortion of the image is corrected by reflection from the half mirror 62. The wearer 63 can observe the image formed by the light scanned in the X and Y directions.

[0203] Since 62 is a half mirror, an image based on light from the outside world and an image based on the scanning light are superimposed and observed by the wearer 63. By providing a mirror instead of half mirror 62, it is possible to eliminate light from the outside world and to configure so that only the image based on the scanning light can be observed.

[0204] In this way, by applying the movable device 13 of the embodiment to a head-mounted display, the swing of the movable part 101 can be controlled with high precision, and a head-mounted display capable of optical scanning with high precision can be provided.

[0205] [Packaging] Next, the packaging of the movable device of this embodiment will be described with reference to FIG.

[0206] FIG. 47 is a schematic diagram of an example of a packaged movable device.

[0207] 47, the movable device 13 is attached to an attachment member 802 arranged inside a packaging member 801, and is packaged by covering a portion of the packaging member with a transparent member 803 and sealing it. Furthermore, an inert gas such as nitrogen is sealed inside the package. This prevents the movable device 13 from deteriorating due to oxidation and improves its durability against environmental changes such as temperature.

[0208] 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 and variations are possible within the scope of the gist of the present invention as described in the claims.

[0209] In the above-described embodiment, a configuration in which a reflective surface is provided on the movable part is exemplified, but this is not limited to this, and the movable part may be provided with other optical elements such as a diffraction grating, a photodiode, a heater (e.g., a heater using SiN), a light source (e.g., a surface-emitting laser), etc., or may be provided with both a reflective surface and other optical elements. [Explanation of symbols]

[0210] 1. Three-dimensional measuring device (example of measuring device) 10 Optical scanning system 11 Control device 12, 12b Light source device 13 Mobile Devices 14 Reflective surface 15 Scanned surface 25 Light source driver 26 Mobile Device Driver 30 Control Unit 31 Drive signal output section 50 Laser headlamp 51 Mirror 52 Transparent plate 60 Head-mounted display 60a Front 60b Temple 61 Light guide plate 62 Half Mirror 63 Wearer 70 Robot 101 Moving parts 102 Movable part base 110a First driving beam 110b Second driving beam 111a 1st torsion beam 111b 2nd torsion beam 112a first piezoelectric driving unit 112b second piezoelectric driving unit 120 1st support part 130a, 130b Pair of drive units 131a to 131f Third piezoelectric driving unit 132a to 132f Fourth piezoelectric driving unit 140 Second support part 150 Electrode connection part 160, 160A, 160B, 160C, 160D, 160E, 160F, 160G, 160H 1st to 4th strain resistors 160a, 160Aa, 160Ba, 160Ca, 160Da, 160Ea, 160Fa, 160Ga, 160Ha First strain resistor 160b, 160Ab, 160Bb, 160Cb, 160Db, 160Eb, 160Fb, 160Gb, 160Hb Secondary strain resistance 160c, 160Ac, 160Bc, 160Cc, 160Dc, 160Ec, 160Fc, 160Gc, 160Hc Third strain resistance 160d, 160Ad, 160Bd, 160Cd, 160Dd, 160Ed, 160Fd, 160Gd, 160Hd 4th strain resistance 201, 301 Lower electrode 202, 302 Piezoelectric part 203, 303 upper electrode 330 Detector 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 measurement device, an example of an object recognition device) 701 Automobile (an example of a vehicle, an example of a moving object) Da, Db, Dc, Dd distance Ex. 2nd oscillation axis Ey 1st oscillation axis Pd1~Pd8 connection terminals V1, V2 voltage i constant current [Prior art documents] [Patent documents]

[0211] [Patent Document 1] Patent No. 5441533

Claims

1. a movable part that swings around at least a first swing axis; a first torsion beam having one end connected to the movable portion; a second torsion beam provided on the opposite side of the first torsion beam with the movable portion interposed therebetween, the second torsion beam having one end connected to the movable portion; a first actuation beam connected to the other end of the first torsion beam; a second actuation beam connected to the other end of the second torsion beam; a first support portion that cantilevers each of the first actuation beam and the second actuation beam; a first strain resistor disposed on the first actuation beam; a second strain resistor disposed on the first actuation beam; a third strain resistor disposed on the second actuation beam; a fourth strain resistor disposed on the second actuation beam; a detection unit that outputs information about the oscillation angle of the movable unit around the first oscillation axis based on the resistance values ​​of the first to fourth strain resistors, the first strain resistor is disposed closer to the free end of the first drive beam than the first oscillation shaft; the third strain resistor is disposed closer to the free end of the second drive beam than the first oscillation shaft, the second strain resistor is disposed closer to either the fixed end side or the free end side of the first actuation beam than the first oscillation shaft, the fourth strain resistor is disposed closer to either the fixed end side or the free end side of the second actuation beam than the first oscillation shaft, a distance between the first strain resistor and the first oscillation axis is longer than a distance between the second strain resistor and the first oscillation axis, so that the resistance change rates of the strain resistors caused by stress are approximately the same; A movable device, wherein the distance between the third strain resistor and the first oscillation axis is longer than the distance between the fourth strain resistor and the first oscillation axis, so that the resistance change rates of each strain resistor caused by stress are approximately the same.

2. each of the first to fourth strain resistors is an N-type piezoresistor; The movable device of claim 1 , wherein each of the first actuation beam and the second actuation beam includes a P-type silicon substrate.

3. each of the first to fourth strain resistors is a P-type piezoresistor; The movable device of claim 1 , wherein each of the first actuation beam and the second actuation beam includes an N-type silicon substrate.

4. a pair of drive units that swing the movable unit around a second swing axis that intersects with the first swing axis; The movable device according to claim 1 , wherein the longitudinal direction of each of the first to fourth strain resistors is a direction along the first oscillation axis.

5. a second support portion that supports the pair of drive portions; each of the pair of drive units has a plurality of beams and a connection unit that folds back and connects the plurality of beams; 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 drive parts is connected to the second support part.

6. The movable device according to claim 1 , wherein the longitudinal direction of each of the first and second torsion beams is parallel to a <100> direction.

7. The movable device according to claim 4 or 5, wherein the longitudinal direction of each of the first and second torsion beams is parallel to a <110> direction.

8. A movable device according to any one of claims 1 to 7; a light source; A distance measuring device that measures the distance to an object by deflecting light emitted from the light source, irradiating the light onto the object, and detecting the light reflected by the object.

9. A measuring device comprising the movable device according to any one of claims 1 to 7.

10. A robot comprising the measurement device according to claim 9.

11. An electronic device comprising the movable device according to any one of claims 1 to 7.

12. A molding apparatus comprising the movable device according to any one of claims 1 to 7.

13. A movable device according to any one of claims 1 to 7; a light source; an image projection device that deflects and projects the light emitted from the light source;

14. A plurality of the light sources are provided, the plurality of light sources emit light of different wavelengths; further comprising a combining unit that combines the plurality of light beams emitted from the plurality of light sources, The image projection device according to claim 13 , wherein the light combined in the combining unit is deflected and projected.

15. A head-up display comprising a movable device according to any one of claims 1 to 7.

16. A laser headlamp comprising a movable device according to any one of claims 1 to 7.

17. A head-mounted display comprising the movable device according to any one of claims 1 to 7.

18. 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, irradiating the object with the light, and detecting the light reflected from the object.

19. A vehicle comprising 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.

20. 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