Movable device, image projection device, head-up display, object recognition device, measuring device, robot, movable body, and vehicle

Abstract

To prevent deviation of a movable part according to acceleration acting on a movable device.SOLUTION: The present movable device comprises a movable part, and a driving part that can rotate the movable part around a rotation axis. The driving part has a plurality of beam parts, first connection parts that connects the adjacent beam parts to each other, and second connection parts that connect the beam parts and the movable part to each other. A distance between the rotation axis and a portion of the second connection part most separated from the rotation axis in an orthogonal direction orthogonal to the rotation axis is longer than a distance between the rotation axis and a portion of the movable part most separated from the rotation axis in the orthogonal direction.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a movable device, an image projection device, a head-up display, an object recognition device, a measuring device, a robot, a moving body, and a vehicle.

Background Art

[0002] In recent years, with the development of micromachining technology applying semiconductor manufacturing technology, the development of MEMS (Micro Electro Mechanical Systems) devices manufactured by microfabricating silicon or glass has been progressing.

[0003] As an MEMS device, for example, a configuration is disclosed that includes a support portion that supports a mirror portion, a piezoelectric actuator in which one end is connected to the mirror portion and the other end is connected to the support portion, and that swings the mirror portion around a predetermined axis with respect to the support portion by piezoelectric driving, and a piezoelectric element for detection that detects vibrations transmitted to the support portion (see, for example, Patent Document 1). This piezoelectric actuator is configured by connecting a plurality of piezoelectric cantilevers in a folded shape, and the piezoelectric element for detection is disposed on the support portion.

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the configuration of the optical deflector exemplified above, when an acceleration acts on a movable device such as an optical deflector, there is a concern that the movable part such as the mirror part may be displaced according to the acting acceleration, and thus light cannot be deflected in a desired direction.

[0005] The present invention has been made in view of the above points, and an object thereof is to suppress displacement of a movable part according to an acceleration acting on the movable device.

Means for Solving the Problems

[0006] A movable device according to one aspect of the present invention includes a movable part and a driving part that can rotate the movable part around a rotation axis. The driving part has a plurality of beam parts, a first connection part that connects adjacent beam parts, and a second connection part that connects the beam parts and the movable part. Among the second connection parts, the distance between the portion farthest from the rotation axis in the orthogonal direction orthogonal to the rotation axis and the rotation axis is longer than the distance between the portion farthest from the rotation axis in the orthogonal direction and the rotation axis among the movable parts.

[0007] A movable device according to one aspect of the present invention includes a movable part and a driving part that can rotate the movable part around a rotation axis. The driving part has a plurality of beam parts, a first connection part that connects adjacent beam parts, and a second connection part that connects the beam parts and the movable part. Among the second connection parts, the distance between the portion farthest from the rotation axis in the orthogonal direction orthogonal to the rotation axis and the rotation axis is longer than the distance between the portion farthest from the rotation axis in the orthogonal direction and the rotation axis among the first connection parts.

Advantages of the Invention

[0008] According to the present invention, it is possible to suppress the displacement of the movable part according to the acceleration acting on the movable device.

Brief Description of the Drawings

[0009]

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Embodiments for Carrying Out the Invention

[0010] Hereinafter, embodiments for carrying out the invention will be described in detail with reference to the drawings. In each drawing, the same reference numerals are assigned to the same components, and duplicate descriptions will be omitted as appropriate.

[0011] In the following description of the embodiments, rotation, oscillation, and movement are considered synonymous. Also, among the directions indicated by the arrows, the stacking direction of each layer in an actuator or the like is the Z direction, and the directions orthogonal to each other within a plane perpendicular to the Z direction are the X direction and the Y direction. In addition, a plan view means looking at the object from the Z direction. However, these do not limit the orientation during the use of the movable device, and the orientation of the movable device is arbitrary.

[0012] <First Embodiment> FIG. 1 is a plan view illustrating an optical deflector which is a movable device according to the first embodiment. FIG. 2 is a cross-sectional view taken along the cutting line A-A of FIG. 1.

[0013] As shown in FIG. 1, the optical deflector 100 includes a movable part 103, actuators 104a and 104b, and a support 120. The optical deflector 100 is an example of a movable device that deflects light incident on the movable part 103 by rotating the movable part 103 around the rotation axis E.

[0014] The movable part 103 includes a mirror part 101 having a substantially rectangular shape in plan view, a mirror reflecting surface 102 formed on the +Z side surface of the base of the mirror part 101, and the like. The mirror part 101 is composed of, for example, a silicon layer. The mirror part 101 may be composed of an oxidizing material, an inorganic material, an organic material, or may be composed of a plurality of materials or a plurality of layers of the same material.

[0015] The mirror reflecting surface 102 is composed of, for example, a metal thin film containing aluminum, gold, silver, or the like, or a multilayer film thereof. Also, a rib structure for reinforcing the mirror part may be formed on the -Z side surface of the base of the mirror part 101. The rib structure is composed of, for example, a silicon support layer and a silicon oxide layer, and suppresses the deformation strain of the mirror part 101 and the mirror reflecting surface 102 caused by movement.

[0016] The movable part 103 is supported in a rotatable state by actuators 104a and 104b. In the present embodiment, the mirror part 101 and the movable part 103 are formed in a substantially rectangular shape in plan view, but the present invention is not limited to this, and they may be formed in a circular shape, an elliptical shape, a polygonal shape, or any other shape.

[0017] Each of the actuators 104a and 104b is an example of a driving part that can rotate the movable part 103 around the rotation axis E. One end of each of the actuators 104a and 104b is connected to the movable part 103, and the other end is connected to the support 120.

[0018] The actuator 104a includes a plurality of beam parts 105a, 105b, 105c, and 105d, first connection parts 108a, 108b, and 108c, and a second connection part 107a.

[0019] The plurality of beam parts 105a, 105b, 105c, and 105d form a meander structure by being connected such that adjacent beam parts are folded back by the first connection parts 108a, 108b, and 108c.

[0020] A second piezoelectric member 110a is provided on the beam part 105a, a first piezoelectric member 110b is provided on the beam part 105b, a second piezoelectric member 110c is provided on the beam part 105c, and a first piezoelectric member 110d is provided on the beam part 105d.

[0021] The actuator 104a is connected to the movable part 103 in a direction intersecting the rotation axis E via the second connection part 107a. The second connection part 107a connects the beam part 105a and the movable part 103. The position where the second connection part 107a connects to the movable part 103 is on the actuator 104a side of the center of the movable part 103 in the direction along the rotation axis E.

[0022] The actuator 104b has a plurality of beam portions 106a, 106b, 106c, and 106d, first connection portions 109a, 109b, and 109c, and a second connection portion 107b.

[0023] The plurality of beam portions 106a, 106b, 106c, and 106d form a folded structure (meander structure) by being connected such that adjacent beam portions are folded back by the first connection portions 109a, 109b, and 109c.

[0024] A first piezoelectric member 111a is provided on the beam portion 106a, a second piezoelectric member 111b is provided on the beam portion 106b, a first piezoelectric member 111c is provided on the beam portion 106c, and a second piezoelectric member 111d is provided on the beam portion 106d.

[0025] The actuator 104b is connected to the movable portion 103 in a direction intersecting the rotation axis E via the second connection portion 107b. The second connection portion 107b connects the beam portion 106a and the movable portion 103. The position where the second connection portion 107b connects to the movable portion 103 is on the actuator 104b side rather than at the center of the movable portion 103 in the direction along the rotation axis E.

[0026] The first piezoelectric members 110b, 110d, 111a, and 111c are deformed when a first driving voltage is applied, and the second piezoelectric members 110a, 110c, 111b, and 111d are deformed when a second driving voltage having a phase opposite to that of the first driving voltage is applied. When each of the first and second piezoelectric members is deformed, a warp occurs in each beam portion.

[0027] Due to the warp of each beam portion, adjacent beam portions bend in different directions, and as the bending is accumulated, the movable portions 103 connected to the actuators 104a and 104b respectively rotate back and forth around the rotation axis E.

[0028] By applying the first driving voltage and the second driving voltage at a driving frequency that matches the resonance mode around the rotation axis E of the movable part 103, the movable part 103 resonates and vibrates, and a large rotation angle can be obtained with a low driving voltage.

[0029] For the waveform of the driving voltage, a sine wave, a sawtooth wave, a triangular wave, or the like can be used. It is not limited to the resonance mode, and the movable part 103 may be rotated in a non-resonance mode. For the driving method of the optical deflector 100, any driving method such as an electrostatic type, a piezoelectric type, or an electromagnetic type may be applied.

[0030] Among these, in terms of being able to effectively arrange the driving part and suppressing the increase in the size of the entire optical deflector, piezoelectric driving is preferable. For example, in electrostatic driving, comb electrodes are arranged on the outer periphery of the driving part, so the size of the entire optical deflector tends to increase. In electromagnetic driving, it is difficult to arrange the wiring layout for each of the plurality of driving parts and the magnets such that a magnetic field is applied to each of them, and the size of the entire optical deflector tends to increase.

[0031] When the driving method is piezoelectric, the cross-sectional structure of the actuator 104a is, for example, as shown in FIG. 2. As shown in FIG. 2, the actuator 104a is composed of a plurality of layers in the thickness direction (Z direction). Specifically, in the actuator 104a, a base portion serving as an elastic portion is formed by a silicon layer 130. The thickness of the silicon layer 130 is, for example, about 20 [μm] to 60 [μm]. The base portion formed by the silicon layer 130 has rigidity and may be formed of an inorganic material, an organic material, a metal glass, or the like as long as it is a material applicable to semiconductor process processing. Also, a multilayer structure in which a plurality of materials are laminated may be used.

[0032] In the actuator 104a, a lower electrode 131, a piezoelectric layer 132, and an upper electrode 133 are sequentially laminated on the +Z side surface of the silicon layer 130. The lower electrode 131, the piezoelectric layer 132, and the upper electrode 133 constitute a piezoelectric driving part.

[0033] The lower electrode 131 and the upper electrode 133 are formed of, for example, gold (Au), platinum (Pt), or the like. The piezoelectric layer 132 is formed of, for example, PZT (lead zirconate titanate), which is a piezoelectric material, but other piezoelectric materials may be used, and the type does not matter.

[0034] Further, the piezoelectric drive unit may have a structure in which a plurality of piezoelectric layers are stacked and include intermediate electrodes. The piezoelectric drive unit is electrically connected to an external control device and is driven by applying a drive voltage. The +Z side of the piezoelectric drive unit is covered with an insulating film (not shown) formed of silicon oxide or the like, and an electrical wiring may be formed on the surface of the insulating film on the +Z side.

[0035] In FIG. 2, the cross-sectional structure of the actuator 104a is illustrated, but the same applies to the actuator 104b.

[0036] Some kind of sensor may be formed in each of the actuators 104a and 104b. The sensor is not particularly limited, and examples include a displacement detection sensor (piezoelectric type, strain gauge type, etc.) that outputs a signal according to deformation, a temperature sensor, and the like.

[0037] <Distance between each end of the movable part, the first connection part, and the second connection part and the rotation axis> In FIG. 1, the distance L1 represents the distance between the rotation axis E and the portion 140a of the second connection part 107a that is farthest from the rotation axis E in the orthogonal direction F orthogonal to the rotation axis E. The distance L2 represents the distance between the rotation axis E and the portion 141 of the movable part 103 that is farthest from the rotation axis E in the orthogonal direction F. The distance L3 represents the distance between the rotation axis E and the portion 142 of the first connection part 108b that is farthest from the rotation axis E in the orthogonal direction F. As shown in FIG. 1, in this embodiment, the distance L1 is longer than the distance L2. Since the distance L2 and the distance L3 are equal, the distance L3 is shown in parentheses in FIG. 1.

[0038] When an acceleration acts in a direction perpendicular to the rotation axis, the movable part may rotate greatly around the rotation axis, causing the initial angle of the movable part to shift. The initial angle refers to the inclination angle of the movable part when the movable part is not rotating. In addition, examples of the above acceleration include the gravitational acceleration acting on the optical deflector, and the acceleration acting on the optical deflector in response to the acceleration of a moving body when the optical deflector is mounted on a moving body such as an automobile or a robot arm.

[0039] FIG. 3 is a diagram showing an example of the deviation of the initial angle of the movable part that occurs when an acceleration acts, and is a view of the movable part 103 in the optical deflector 100 of FIG. 1 as viewed from the -Y side. In FIG. 3, illustration of components other than the movable part 103 in the optical deflector 100 is omitted.

[0040] In FIG. 3, the initial angle of the movable part 103 is inclined by an angle θ with respect to the angle reference A0. The angle reference A0 corresponds to, for example, the mirror reflecting surface 102 of the movable part 103 when the initial angle of the movable part 103 is in an ideal state. When an acceleration in the +X direction acts on the optical deflector 100, the movable part 103 is in a state where the initial angle is deviated by an angle θ with respect to the angle reference A0.

[0041] When the movable part 103 rotates in a state where the initial angle is deviated by the angle θ, the deflection direction of the light incident on the mirror reflecting surface 102 of the movable part 103 and deflected by the optical deflector 100 deviates from the desired direction corresponding to the angle θ.

[0042] There is a relationship represented by the following equation between the angle θ and the distance L1. Therefore, the larger the distance L1, the more the angle θ is suppressed. θ ∝ 1 / L1 2

[0043] <Operating effects of the optical deflector 100> As described above, the optical deflector 100 (movable device) according to the present embodiment includes a movable part 103 and an actuator 104a (driving part) that can rotate the movable part 103 around a rotation axis E. The actuator 104a has a plurality of beam parts 105a, 105b, 105c, and 105d, first connection parts 108a, 108b, and 108c that connect adjacent beam parts, and a second connection part 107a.

[0044] Among the second connection part 107a, the distance L1 between the portion 140a that is farthest from the rotation axis E in the orthogonal direction F orthogonal to the rotation axis E and the rotation axis E is longer than the distance L2 between the portion 141 that is farthest from the rotation axis E in the orthogonal direction F among the movable part 103 and the rotation axis E. With this configuration, the angle θ, which is the deviation of the initial angle with respect to the angle reference A0, can be suppressed.

[0045] On the other hand, if the area of the movable part 103 increases by increasing the distance L1, there is a concern of causing a decrease in the resonance frequency and a decrease in the driving sensitivity. Note that the driving sensitivity refers to the rotation angle per unit driving voltage.

[0046] In the present embodiment, by making the distance L1 longer than the distance L2, it is possible to prevent the area of the movable part 103 from increasing, and while avoiding a decrease in the resonance frequency and a decrease in the driving sensitivity associated with increasing the distance L1, the angle θ can be suppressed.

[0047] Also, in the present embodiment, the actuator 104a is connected to the movable part 103 in a direction intersecting the rotation axis E via the second connection part 107a. Thereby, when making the distance L1 longer than the distance L2, it becomes easier to arrange the second connection part 107a.

[0048] Also, in the present embodiment, the position where the second connection part 107a is connected to the movable part 103 is on the actuator 104a side rather than the center of the movable part 103 in the direction along the rotation axis E. Thereby, when making the distance L1 longer than the distance L2, it becomes easier to arrange the second connection part 107a.

[0049] In the present embodiment, a configuration in which the distance L2 and the distance L3 are equal has been exemplified. However, if the distance L1 is longer than the distance L2, the length of the distance L3 may be arbitrary. However, making the distance L2 and the distance L3 equal is more preferable because the configurations of the actuators 104a and 104b and the movable part 103 can be simplified.

[0050] Also, in the present embodiment, a configuration has been exemplified in which the end face of the movable part 103 including the end of the movable part 103 in the orthogonal direction F is substantially parallel to the rotation axis E. However, the present invention is not limited to this. Even if the end face of the movable part 103 intersects the rotation axis E, by making the distance L1 longer than the distance L2, the same operational effects as described above can be obtained.

[0051] Also, although the operational effect of the actuator 104a has been described, the same applies to the actuator 104b. That is, in the actuator 104b, among the second connection parts 107b, the distance L1 between the portion 140b that is farthest from the rotation axis E in the orthogonal direction F and the rotation axis E is longer than the distance L2 between the portion 141 that is farthest from the rotation axis E in the orthogonal direction F of the movable part 103 and the rotation axis E. Also with this configuration, the same operational effects as described above can be obtained. In other words, by making the distance L1 in at least one of the second connection parts 107a or 107b longer than the distance L2, the above-described operational effects can be obtained.

[0052] Also, a case has been exemplified in which the distance between the portion 140a in the orthogonal direction F and the rotation axis E is equal to the distance between the portion 140b in the orthogonal direction F and the rotation axis E. However, the present invention is not limited to this, and the two may be different. When the two are different, the distance between the one of the portion 140a and the portion 140b that is farther from the rotation axis E and the rotation axis E corresponds to the distance L1. By this distance L1 satisfying the above conditions, the same operational effects as described above can be obtained.

[0053] <Modification Example> Next, a modification example of the first embodiment will be described. Note that the same reference numerals are given to the same components as those in the above-described embodiment, and redundant explanations are appropriately omitted.

[0054] FIG. 4 is a plan view illustrating the optical deflector 100a according to the first modification. As shown in FIG. 4, in this modification, the distance L1 is longer than the distance L3. Even with this configuration, the angle θ, which is the deviation of the initial angle with respect to the angle reference A0, can be suppressed. Further, by preventing an increase in the area of the movable part 103, it is possible to avoid a decrease in the resonance frequency and a decrease in the driving sensitivity associated with increasing the distance L1.

[0055] Note that if the distance L1 is longer than the distance L3, the length of the distance L2 may be arbitrary. However, if the distances L1, L2, and L3 satisfy the following relationship (1), the spring constants of the actuators 104a and 104b can be made smaller, which is advantageous in terms of improving the driving sensitivity and increasing the rotation angle. L1>L3>L2 ··· (1)

[0056] Next, FIG. 5 is a plan view illustrating the optical deflector 100b according to the second modification. As shown in FIG. 5, in this modification, the following relationship (2) exists among the distance L1, the distance L2, and the distance L3. L1>L2>L3 ··· (2)

[0057] With this configuration, the spring constants of the actuators 104a and 104b can be increased, which is advantageous in terms of improving the fracture resistance when an impact is applied to the optical deflector 100b.

[0058] Next, FIG. 6 is a plan view illustrating the optical deflector 100c according to the third modification. Further, FIG. 7 is a plan view illustrating the optical deflector 100d according to the fourth modification.

[0059] As shown in FIG. 6, in the optical deflector 100c, the position where the second connection portion 107ac is connected to the movable portion 103 is the center of the movable portion 103 in the direction along the rotation axis E. Further, as shown in FIG. 7, in the optical deflector 100d, the position where the second connection portion 107ad is connected to the movable portion 103 is on the side opposite to the actuator 104a from the center of the movable portion 103 in the direction along the rotation axis E.

[0060] As shown in the third and fourth modified examples, the position where the second connecting portion 107a is connected to the movable portion 103 is arbitrary in the direction along the rotation axis E, and the same operational effects as those of the first embodiment can be obtained at any position. Further, by combining the third or fourth modified example with the first modified example, the same operational effects as those of the first modified example can be obtained, and by combining with the second modified example, the same operational effects as those of the second modified example can be obtained.

[0061] Next, FIG. 8 is a plan view illustrating an optical deflector 100e according to a fifth modified example. As shown in FIG. 7, the optical deflector 100e has second connecting portions 107ea and 107eb.

[0062] The second connecting portion 107ea has a shape in which the width along the orthogonal direction F is longer toward the +Y side and has a substantially triangular shape in plan view. The second connecting portion 107eb has a shape in which the width along the orthogonal direction F is longer toward the -Y side and has a substantially triangular shape in plan view.

[0063] The coupling shape 150 between the movable portion 103 and the second connecting portions 107ea and 107eb is a parallelogram shape in plan view. With this configuration, the length of the portion where each of the second connecting portions 107ea and 107eb is connected to the movable portion 103 can be increased, and each of the second connecting portions 107ea and 107eb and the movable portion 103 can be stably connected.

[0064] Note that the shapes of the second connecting portions 107ea and 107eb are not limited to substantially triangular shapes and can be arbitrarily selected. Therefore, by adjusting the shapes of the second connecting portions 107ea and 107eb, it is possible to adjust the interval between a plurality of natural vibration modes of the optical deflector 100e and the like.

[0065] The optical deflectors according to the embodiments described above can be used in an optical scanning system, an optical deflection system, an image projection device, an optical writing device, an object recognition device, a laser head lamp, and a head-mounted display. Each will be sequentially described below.

[0066] [Optical Scanning System] First, an optical scanning system to which the movable device according to the embodiment is applied will be described in detail with reference to FIGS. 9 to 12.

[0067] FIG. 9 shows a schematic diagram of an example of the optical scanning system. As shown in FIG. 9, the optical scanning system 10 is a system that deflects the light irradiated from the light source device 12 according to the control of the control device 11 by the reflecting surface 14 of the movable device 13 and optically scans the surface to be scanned 15.

[0068] The optical scanning system 10 is composed of a control device 11, a light source device 12, and a movable device 13 having a reflecting surface 14.

[0069] The control device 11 is an electronic circuit unit including, for example, a CPU (Central Processing Unit) and an FPGA (Field-Programmable Gate Array). The movable device 13 is, for example, a MEMS (Micro Electromechanical Systems) device having a reflecting surface 14 and capable of moving the reflecting surface 14. The light source device 12 is, for example, a laser device that irradiates a laser. The surface to be scanned 15 is, for example, a screen.

[0070] The control device 11 generates control commands for the light source device 12 and the movable device 13 based on the acquired optical scanning information, and outputs drive signals to the light source device 12 and the movable device 13 based on the control commands.

[0071] The light source device 12 irradiates light based on the input drive signal. The movable device 13 moves the reflecting surface 14 in at least one of the one-axis direction or the two-axis direction based on the input drive signal.

[0072] Accordingly, for example, by the control of the control device 11 based on image information which is an example of the optical scanning information, the reflecting surface 14 of the movable device 13 is reciprocally movable in two axial directions within a predetermined range, and the irradiation light from the light source device 12 incident on the reflecting surface 14 is deflected around a certain axis for optical scanning, whereby an arbitrary image can be projected onto the surface to be scanned 15. Details of the movable device and details of the control by the control device according to the embodiment will be described later.

[0073] Next, the hardware configuration of an example of the optical scanning system 10 will be described with reference to FIG. 10. FIG. 10 is a hardware configuration diagram of an example of the optical scanning system 10. As shown in FIG. 10, the optical scanning system 10 includes a control device 11, a light source device 12, and a movable device 13, each of which is electrically connected. Among these, the control device 11 includes a CPU 20, a RAM 21 (Random Access Memory), a ROM 22 (Read Only Memory), an FPGA 23, an external I / F 24, a light source device driver 25, and a movable device driver 26.

[0074] The CPU 20 is an arithmetic device that reads 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.

[0075] The RAM 21 is a volatile storage device that temporarily holds programs and data.

[0076] The ROM 22 is a non-volatile storage device that can hold programs and data even when the power is turned off, and stores processing programs and data for the CPU 20 to control each function of the optical scanning system 10.

[0077] The FPGA 23 is a circuit that outputs control signals suitable for the light source device driver 25 and the movable device driver 26 according to the processing of the CPU 20.

[0078] The external I / F 24 is an interface with, for example, an external device or a network. The external devices include, for example, a host device such as a PC (Personal Computer), and storage devices such as a USB memory, an SD card, a CD, a DVD, an HDD, and an SSD. The network is, for example, the CAN (Controller Area Network) of an automobile, a LAN (Local Area Network), the Internet, or the like. The external I / F 24 may be configured to enable connection or communication with an external device, and an external I / F 24 may be prepared for each external device.

[0079] The light source device driver 25 is an electric circuit that outputs a drive signal such as a drive voltage to the light source device 12 according to the input control signal.

[0080] The movable device driver 26 is an electric circuit that outputs a drive signal such as a drive voltage to the movable device 13 according to the input control signal.

[0081] 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. For example, the optical scanning information may be stored in the ROM 22 or the FPGA 23 in the control device 11, or a new storage device such as an SSD may be provided in the control device 11 to store the optical scanning information therein.

[0082] Here, the optical scanning information is information indicating how to perform optical scanning on the surface to be scanned 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 the writing location. Additionally, for example, when object recognition is performed by optical scanning, the optical scanning information is irradiation data indicating the timing and the irradiation range for irradiating light for object recognition.

[0083] The control device 11 can realize the functional configuration described below based on the instructions of the CPU 20 and the hardware configuration shown in FIG. 10.

[0084] Next, the functional configuration of the control device 11 of the optical scanning system 10 will be described with reference to FIG. 11. FIG. 11 is a functional block diagram of an example of the control device of the optical scanning system.

[0085] As shown in FIG. 11, the control device 11 has, as functions, a control unit 30 and a drive signal output unit 31.

[0086] The control unit 30 is realized by, for example, a CPU 20, an FPGA 23, etc. It 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 as optical scanning information from an external device or the like, generates a control signal from the image data by a predetermined process, and outputs it to the drive signal output unit 31. The drive signal output unit 31 is realized by a light source device driver 25, a 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.

[0087] The drive signal is a signal for controlling the driving of the light source device 12 or the movable device 13. For example, in the light source device 12, it is a drive voltage for controlling the irradiation timing and irradiation intensity of the light source. Also, for example, in the movable device 13, it is a drive voltage for controlling the timing and movable range for moving the reflecting surface 14 of the movable device 13.

[0088] Next, the process of the optical scanning system 10 optically scanning the surface to be scanned 15 will be described with reference to FIG. 12. FIG. 12 is a flowchart of an example of the process related to the optical scanning system.

[0089] In step S11, the control unit 30 acquires optical scanning information from an external device or the like.

[0090] 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.

[0091] 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.

[0092] In step 14, the light source device 12 performs light irradiation based on the input drive signal. Also, the movable device 13 moves the reflecting surface 14 based on the input drive signal. By driving the light source device 12 and the movable device 13, light is deflected in an arbitrary direction and light scanning is performed.

[0093] Note that in the above light scanning system 10, although one control device 11 has the devices and functions for controlling the light source device 12 and the movable device 13, they may be provided separately as a control device for the light source device and a control device for the movable device.

[0094] Also, in the above light scanning system 10, although the functions of the control unit 30 and the drive signal output unit 31 for the light source device 12 and the movable device 13 are provided in one control device 11, these functions may exist separately. For example, a configuration may be adopted in which a drive signal output device having a drive signal output unit 31 is provided separately from the control device 11 having the control unit 30. Note that among the above light scanning system 10, a light deflection system that performs light deflection may be configured by the movable device 13 having the reflecting surface 14 and the control device 11.

[0095] By using the movable device according to this embodiment in the light scanning system in this way, it is possible to suppress the displacement of the movable part according to the acceleration acting on the movable device and appropriately scan light.

[0096] [Image projection device] Next, an image projection device to which the movable device according to the embodiment is applied will be described in detail with reference to FIGS. 13 and 14. The image projection device is a device that projects an image by light scanning, for example, a head-up display device.

[0097] FIG. 13 is a schematic diagram of an automobile 400 equipped with a head-up display device 500 which is an example of an image projection device. FIG. 14 is a schematic diagram of an example of the head-up display device 500.

[0098] As shown in FIG. 13, the head-up display device 500 is installed, for example, near the windshield (such as the front glass 401) of the automobile 400. The projection light L emitted from the head-up display device 500 is reflected by the front glass 401 and travels toward the observer (driver 402) who is the user. Thereby, the driver 402 can visually recognize an image or the like 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 visually recognize a virtual image by the projection light reflected by the combiner.

[0099] As shown in FIG. 14, laser light is emitted from red, green, and blue laser light sources 501R, 501G, and 501B of the head-up display device 500. The emitted laser light passes through an incident optical system composed of collimating lenses 502, 503, and 504 provided for the respective laser light sources, two dichroic mirrors 505 and 506, and a light quantity adjustment unit 507, and then is deflected by a movable device 13 having a reflecting surface 14. Then, the deflected laser light passes through a projection optical system composed of a free-form surface mirror 509, an intermediate screen 510, and a projection mirror 511, and is projected onto the screen. In the head-up display device 500, the laser light sources 501R, 501G, and 501B, the collimating lenses 502, 503, and 504, and the dichroic mirrors 505 and 506 are unitized as a light source unit 530 by an optical housing.

[0100] The head-up display device 500 projects the intermediate image displayed on the intermediate screen 510 onto the front glass 401 of the automobile 400, so that the driver 402 can visually recognize the intermediate image as a virtual image.

[0101] The laser light of each color emitted from the laser light sources 501R, 501G, and 501B is made into substantially parallel light by the collimating lenses 502, 503, and 504, respectively, and is combined by two dichroic mirrors 505 and 506 serving as a combining unit. The combined laser light is adjusted in light quantity by the light quantity adjusting unit 507, and then two-dimensionally scanned by the movable device 13 having the reflecting surface 14. The projected light L two-dimensionally scanned by the movable device 13 is reflected by the free-form surface mirror 509 to correct distortion, and then condensed on the intermediate screen 510 to display an intermediate image. The intermediate screen 510 is composed of a microlens array in which microlenses are two-dimensionally arranged, and enlarges the projected light L incident on the intermediate screen 510 in units of microlenses.

[0102] The movable device 13 reciprocates the reflecting surface 14 in two axial directions and two-dimensionally scans the projected light L incident on the reflecting surface 14. The drive control of this movable device 13 is performed in synchronization with the light emission timings of the laser light sources 501R, 501G, and 501B.

[0103] As described above, the head-up display device 500 has been described as an example of the image projection device. However, the image projection device may be any device that projects an image by performing optical scanning with the movable device 13 having the reflecting surface 14. For example, a projector placed on a desk or the like and projecting an image on a display screen, or a head-mounted display device mounted on a mounting member worn on an observer's head or the like and projecting an image on a reflective transmission screen of the mounting member or projecting an image using the eyeball as a screen can also be similarly applied.

[0104] In addition, the image projection device may be mounted not only on a vehicle or a mounting member, but also on a moving body including, for example, an aircraft, a ship, a mobile robot, etc. in addition to the vehicle, or a non-moving body such as a work robot that operates a drive target such as a manipulator without moving from the spot. The automobile 400 is an example of a moving body and an example of a vehicle.

[0105] By using the movable device according to this embodiment in an image projection device, it is possible to suppress the displacement of the movable part according to the acceleration acting on the movable device and project a high-quality image.

[0106] [Object recognition device] Next, an object recognition device to which the movable device according to the embodiment is applied will be described in detail with reference to FIGS. 15 and 16. The object recognition device is a device that recognizes an object in a target direction, and is, for example, a LiDAR device.

[0107] FIG. 15 is a schematic diagram of an automobile equipped with a LiDAR (Laser Imaging Detection and Ranging) device, which is an example of an object recognition device. FIG. 16 is a schematic diagram of an example of the LiDAR device.

[0108] As shown in FIG. 15, the LiDAR device 700 is mounted on, for example, an automobile 701, optically scans the target direction, and receives reflected light from a target object 702 existing in the target direction, thereby recognizing the target object 702.

[0109] As shown in FIG. 16, the laser light emitted from the light source device 12 passes through an incident optical system composed of a collimating lens 703, which is an optical system that makes divergent light into substantially parallel light, and a plane mirror 704, and is scanned in one-axis or two-axis directions by a movable device 13 having a reflecting surface 14. Then, it is irradiated onto the target object 702 in front of the device through a projection optical system such as a projection lens 705. The light source device 12 and the movable device 13 are driven and controlled by a control device 11. The reflected light reflected by the target object 702 is detected by a photodetector 709. That is, the reflected light is received by an imaging element 707 through a condensing lens 706 and the like, which is an incident light detection and receiving optical system, and the imaging element 707 outputs a detection signal to a signal processing circuit 708. The signal processing circuit 708 performs predetermined processing such as binarization and noise processing on the input detection signal, and outputs the result to a distance measurement circuit 710.

[0110] The distance measurement circuit 710 recognizes the presence or absence of the object 702 based on the time difference between the timing when the light source device 12 emits laser light and the timing when the photodetector 709 receives the laser light, or the phase difference for each pixel of the image sensor 707 that has received the light, and further calculates the distance information to the object 702.

[0111] The movable device 13 having the reflecting surface 14 is less likely to be damaged compared to a polygonal mirror and is small in size, so a small and highly durable radar device can be provided. Such a lidar device can be attached to, for example, a vehicle, an aircraft, a ship, a robot, etc., and can optically scan a predetermined range to recognize the presence or absence of obstacles and the distance to the obstacles.

[0112] In the above object recognition device, although the lidar device 700 has been described as an example, the object recognition device may be any device that performs optical scanning by controlling the movable device 13 having the reflecting surface 14 with the control device 11 and recognizes the object 702 by receiving the reflected light with a photodetector, and is not limited to the above-described embodiment.

[0113] For example, biometric authentication that calculates object information such as shape from the distance information obtained by optically scanning a hand or a face, records and refers to it to recognize the object, a security sensor that recognizes an intruder by optically scanning a target range, and a component of a 3D scanner that calculates and recognizes object information such as shape from the distance information obtained by optical scanning and outputs it as 3D data can be similarly applied.

[0114] By using the movable device according to the embodiment in an object recognition device in this way, it is possible to suppress the displacement of the movable part according to the acceleration acting on the movable device and provide an object recognition device with high recognition accuracy.

[0115] [Packaging] Next, the packaging of the movable device according to the embodiment will be described with reference to FIG. 17. FIG. 17 is a schematic diagram of an example of the packaged movable device.

[0116] As shown in FIG. 17, the movable device 13 is attached to an attachment member 802 disposed inside the package member 801, and a part of the package member 801 is covered with a transmissive member 803 and sealed to be packaged. Further, an inert gas such as nitrogen is sealed inside the package. Thereby, deterioration due to oxidation of the movable device 13 is suppressed, and furthermore, the durability against environmental changes such as temperature is improved.

[0117] [Measuring device] Next, a measuring device to which the movable device 13 according to the embodiment is applied will be described in detail with reference to FIGS. 18 and 19. Here, a three-dimensional measuring device that performs three-dimensional measurement of an object using the pattern projection method is taken as an example of the measuring device. FIG. 18 is a block diagram showing an example of the configuration of the three-dimensional measuring device. FIG. 19 is a diagram showing a state in which a measurement pattern is projected onto an object by the three-dimensional measuring device.

[0118] As shown in FIG. 18, the three-dimensional measuring device 1 includes a measurement information acquisition unit 20 and a control unit 300.

[0119] The measurement information acquisition unit 20 includes a projection device 2 and a camera device 21. The projection device 2 shown in FIG. 1 includes a VCSEL array (Vertical Cavity Surface Emitting LASER) 3, an optical system 4, and a movable device 13. By using the VCSEL array 3 as a light source, the emission interval can be made fine and a plurality of focal points can be formed.

[0120] The measurement information acquisition unit 20 deflects the light of a plurality of light-emitting elements included in the VCSEL array 3 by the movable device 13 and projects it onto the object in the measurement area according to the control of the control unit 301 of the control unit 300. The control unit 301 controls the luminance and lighting timing of each light-emitting element of the VCSEL array 3 to project the projection light 6 of a predetermined measurement pattern onto the entire measurement area including the object 7 as shown in FIG. 19.

[0121] As a 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. 18, an optical system 4 for making the light of the VCSEL array 3 linear is provided independently of the light source unit, but it may be included in the light source unit.

[0122] The camera device 21 images the above-described measurement region at a position and an angle fixed so that the projection center 41 of the projection light 6 projected by the projection device 2 onto the object is substantially at the center of the imaging region 40.

[0123] The camera device 21 includes a lens 210, which is a light-receiving optical system, and an imaging element 211. As the imaging element 211, for example, an image sensor such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) can be used. The light incident on the camera device 21 forms an image on the imaging element 211 via the lens 210 and is photoelectrically converted. The image signal generated by photoelectric conversion by the imaging element 211 is supplied to the arithmetic processing unit 302 of the control unit 300.

[0124] A narrow-band filter that transmits the emission wavelength of the VCSEL array 3 may be used for the lens 210. Thereby, the influence of ambient light (light that causes interference such as fluorescent lamps) during measurement can be suppressed, and accurate measurement can be enabled. Note that a narrow-band filter may be provided in the front stage of the lens 210. Also in this case, the same effect can be obtained.

[0125] The control unit 300 performs projection control of the measurement pattern light and imaging control by the camera device 21 by the projection device 2, and performs arithmetic processing such as three-dimensional measurement of the measurement object based on information regarding the image captured by the camera device 21. Note that the control unit 301 may perform control to switch the measurement pattern light projected by the projection device 2 to another pattern light. Also, the control unit 301 may perform output control of calibration information used by the arithmetic processing unit 302 for calculating three-dimensional coordinates.

[0126] Based on the information regarding the supplied image, the arithmetic processing unit 302 of the control unit 300 calculates (measures) the three-dimensional coordinates corresponding to the three-dimensional shape of the object 7, or information regarding the three-dimensional coordinates. The arithmetic processing unit 302 may output the three-dimensional shape information indicating the calculated three-dimensional shape to an external device such as a personal computer device according to the control of the control unit 301.

[0127] Note that FIG. 18 shows an example in which one set of measurement information acquisition units 20 is provided for the control unit 300, but a plurality of sets of measurement information acquisition units 20 may be provided for the control unit 300. Also, FIG. 18 shows an example in which the measurement information acquisition unit 20 and the control unit 300 are provided independently, but a part or all of the control unit 300 may be included in the measurement information acquisition unit 20.

[0128] By using the movable device according to the embodiment as a measuring device in this way, it is possible to suppress the displacement of the movable part according to the acceleration acting on the movable device and provide a measuring device with high measurement accuracy.

[0129] [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. 20. FIG. 20 is a diagram showing a robot arm having multiple joints of the robot 70.

[0130] In FIG. 20, the robot arm 72, which is a multi-joint arm, includes a hand part 71 for picking up the object 7, and a three-dimensional measuring device 1 is provided in the immediate vicinity of the hand part 71. The robot arm 72 includes a plurality of joints that can be bent respectively, and changes the position and posture of the hand part 71 according to the control.

[0131] The three-dimensional measuring device 1 is provided so that the projection direction of light coincides with the direction in which the hand part 71 faces, and measures the picking target of the hand part 71 as the object 7 to be measured.

[0132] The robot 70 can measure the object 7 to be picked up at a short distance by the three-dimensional measuring device 1 provided on the robot arm 72. Therefore, compared with the case of measuring the object 7 to be picked up from a distance by a camera device or the like, the measurement accuracy can be improved. For example, in the FA field in various assembly lines in a factory, etc., the robot 70 equipped with the robot arm 72 is used for inspecting and recognizing parts. By providing the three-dimensional measuring device 1 on the robot 70, the inspection and recognition of parts can be performed accurately.

[0133] Also, when there is an invalid area in the imaging 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 the three-dimensional shape is fed back to the robot arm 72. Thereby, the control of the robot arm 72 can be easily performed, and more accurate part inspection or recognition can be performed based on the measurement result with data complementation.

[0134] Also, the relationship between the position and orientation of the measuring instrument and the measurement object may be changed relatively. For this reason, although the three-dimensional measuring device 1 is provided on the robot arm 72, the measurement object may be provided on the robot arm 72 and the position and orientation may be changed.

[0135] When the three-dimensional measuring device 1 is mounted on the robot arm 72 to perform three-dimensional measurement of the object to be measured, 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, and this is achieved in this embodiment.

[0136] By using the movable device according to the embodiment in a robot in this way, it is possible to suppress the displacement of the movable part according to the acceleration acting on the movable device and provide a robot capable of controlling the position and orientation with high accuracy.

[0137] As described above, the preferred embodiments etc. have been described in detail, but it is not limited to the above-described embodiments etc., and various modifications and substitutions can be added to the above-described embodiments etc. without departing from the scope described in the claims.

[0138] For example, in each of the above embodiments, the movable part has a mirror part. However, the movable part may have a diffraction grating, a photodiode, a heater (e.g., a heater using SiN), a light source (e.g., a surface-emitting laser), etc. instead of the mirror part.

Explanation of Reference Numerals

[0139] 1 Three-dimensional measuring device 2 Projection device 3 VCSEL array 4 Optical system 6 Projection light 7 Object 70 Robot 71 Hand part 72 Robot arm 10 Optical scanning system 11 Control device 12, 12b Light source device 13 Movable device 14 Reflecting surface 15 Scanned surface 25 Light source device driver 26 Movable device driver 30 Control unit 31 Drive signal output unit 100 Optical deflector (an example of a movable device) 101 Mirror part 102 Mirror reflecting surface 103 Movable part 104a, 104b Actuator (an example of a drive part) 105a, 105b, 105c, 105d Beam part 106a, 106b, 106c, 106d Beam part 107a, 107b Second connection part 108a, 108b, 108c First connection part 109a, 109b, 109c First connection part 110b, 110d, 111a, 111c First piezoelectric member 110a, 110c, 111b, 111d Second piezoelectric member 130 Silicon layer 131 Lower electrode 132 Piezoelectric layer 133 Upper electrode 140a, 140b Among the second connection parts, the part farthest from the rotation axis in the orthogonal direction 141 Among the movable parts, the part farthest from the rotation axis in the orthogonal direction 142 Among the first connection parts, the part farthest from the rotation axis in the orthogonal direction 150 Coupling shape 400 Automobile (an example of a moving body, an example of a vehicle) E Rotation axis F Orthogonal direction L1, L2, L3 Distances θ Angle

Prior art documents

Patent documents

[0140]

Patent Document 1

Claims

1. A movable part; A drive unit capable of rotating the movable unit around a rotation axis, The drive unit is A plurality of beams; a first connection portion that connects adjacent beam portions; a second connection portion that connects the beam portion and the movable portion, A movable device characterized in that a distance between the rotation axis and a portion of the second connection portion that is farthest from the rotation axis in a direction perpendicular to the rotation axis is longer than a distance between the rotation axis and a portion of the first connection portion that is farthest from the rotation axis in the perpendicular direction.

2. The movable device according to claim 1 , wherein the driving portion is connected to the movable portion in a direction intersecting the rotation axis via the second connection portion.

3. The movable device according to claim 1 or 2, characterized in that the distance between the rotation axis and a portion of the second connection portion that is farthest from the rotation axis in the orthogonal direction is L1, the distance between the rotation axis and a portion of the movable portion that is farthest from the rotation axis in the orthogonal direction is L2, and the distance between the rotation axis and a portion of the first connection portion that is farthest from the rotation axis in the orthogonal direction is L3, satisfies the condition of the following equation (1). L1>L3>L2... (1)

4. The movable device according to claim 1 or 2, characterized in that the distance between the rotation axis and a portion of the second connection portion farthest from the rotation axis in the orthogonal direction is L1, the distance between the rotation axis and a portion of the movable portion farthest from the rotation axis in the orthogonal direction is L2, and the distance between the rotation axis and a portion of the first connection portion farthest from the rotation axis in the orthogonal direction is L3, satisfies the condition of the following equation (2). L1>L2>L3... (2)

5. 5. The movable device according to claim 1, wherein the second connection portion is connected to the movable portion at a position closer to the driving portion than a center of the movable portion in a direction along the rotation axis.

6. 5. The movable device according to claim 1, wherein the second connection portion is connected to the movable portion at a center of the movable portion in a direction along the rotation axis.

7. 5. The movable device according to claim 1, wherein the position at which the second connection portion is connected to the movable portion is on the opposite side to the drive portion from the center of the movable portion in the direction along the rotation axis.

8. 5. The movable device according to claim 1, wherein a combined shape of the movable portion and the second connection portion is a parallelogram in a plan view.

9. A movable device according to any one of claims 1 to 8; A light source that emits light; Equipped with An image projection device which projects light emitted from the light source by deflecting the light.

10. The light source is provided in plurality, The plurality of light sources emit light of different wavelengths, A combining unit that combines the plurality of light beams emitted from the plurality of light sources, 10. The image projection device according to claim 9, wherein the light combined in the combining section is deflected and projected.

11. A head-up display comprising a movable device according to any one of claims 1 to 8.

12. A movable device according to any one of claims 1 to 8; A light source that emits light, An object recognition device comprising: a light source that is deflected, the light is irradiated onto an object, and the reflected light reflected by the object is detected, thereby recognizing the object.

13. A movable device according to any one of claims 1 to 8; A light source that emits light; Equipped with A measuring apparatus comprising: a light source that is deflected; an object is irradiated with the light; and a shape of the object is measured based on the light reflected by the object.

14. A robot comprising the measuring device according to claim 13.

15. A moving object comprising at least one of the head-up display according to claim 11 and the object recognition device according to claim 12.

16. A vehicle comprising at least one of the head-up display according to claim 11 or the object recognition device according to claim 12.

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