Movable devices, optical deflection devices, image projection devices, mobile bodies and head-mounted displays

Abstract

To shorten adjustment processing time of an elastic vibration.SOLUTION: A movable device of the invention comprises: a reflection part; a pair of movable parts which applies each inclination to the reflection part; and a control part for inputting a drive signal for applying inclination to the pair of movable parts. The control part comprises: a drive signal generation part for generating a drive signal in which, a standing ratio of the drive signals to be input to the pair of movable parts, and a phase difference between the drive signal are variable numbers; a high frequency component extraction part for extracting a high frequency component from a signal corresponding to a vibration angle of the movable part, the vibration angle being detected by driving by the drive signal generated by the drive signal generation part; a memory part for associating values of the variable numbers of the drive signals with the high frequency component and storing them; and a drive signal selecting part for selecting a combination of the values of the variable numbers for updating the drive signal, on the basis of the high frequency component stored in the memory part.SELECTED DRAWING: Figure 17

Description

Technical Field

[0001] The present invention relates to a movable device, an optical deflection device, an image projection device, a moving body, and a head-mounted display.

Background Art

[0002] Conventionally, a movable device is provided with a reflecting portion for scanning light on a movable portion elastically supported by a fixed frame, and by repeatedly performing a tilting operation for changing the tilt angle of the reflecting portion by the movable portion, scanning in the horizontal and vertical directions is performed.

[0003] The actual tilt swing angle taken by the movable portion varies up and down with time with respect to the ideal tilt swing angle. This time variation is due to a high frequency superimposed on the tilting operation of the movable portion, and this high frequency is canceled out by the following method.

[0004] For example, by changing the symmetry ratio between the rise and fall of the drive signal for each high frequency superimposed on the tilting operation of the movable portion by two drive signals and adjusting the phase difference between the two drive signals, the high frequency is canceled out by changing the setting.

[0005] Also, Patent Document [1] discloses a configuration in which tilt swing angle information indicating the tilt swing angle of the movable portion is detected, and the amplitude and phase difference of the drive signal are corrected so that the amount of change of the detected tilt swing angle with respect to the target tilt swing angle becomes small.

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, when canceling the high frequency by changing the setting for the drive signal, there is a problem that elastic vibration occurs separately in the movable portion at the time of setting change or the like, and adjustment processing time is required until the elastic vibration subsides.

[0007] The present invention has been made in view of the above-mentioned problems, and aims to provide a movable device, an optical deflection device, an image projection device, a mobile body, and a head-mounted display that can shorten the adjustment processing time for elastic vibration. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems and achieve the objective, the movable device according to the present invention comprises a reflective part, a pair of movable parts that give the reflective part their respective inclinations, and each movable part In contrast, The system includes a control unit which inputs a drive signal that provides the aforementioned tilt, and the control unit is Can be written moving parts Enter to exert As a drive signal, The drive signal In the waveform of the period of the drive voltage waveform The start period ratio rate and Input to each of the aforementioned movable parts Let the phase difference between the drive signals be a variable. ru A drive signal generation unit that generates a motion signal, and the drive that is detected by the drive signal generated by the drive signal generation unit. Reflector A high-frequency component extraction unit that extracts high-frequency components from the signal corresponding to the deflection angle, and the variable of the drive signal Set to Value and Extracted from the aforementioned high-frequency component extraction unit A memory unit that stores the aforementioned high-frequency components in association with each other, Based on the combinations of values ​​set for each variable, multiple combinations are set for each variable by changing the values ​​of each variable to other combinations, and from these multiple combinations, the combination of variable values ​​that minimizes the high-frequency amplitude of the high-frequency component is selected. It includes a drive signal selection unit. [Effects of the Invention]

[0009] The present invention has the effect of shortening the adjustment processing time for elastic vibrations. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 is a plan view of a movable device in which the first drive unit is of the cantilever type. [Figure 2] Figure 2 is a cross-sectional view of the movable device in Figure 1 along the second axis. [Figure 3] Figure 3 is a plan view of a movable device in which the first drive unit is of the double-supported type. [Figure 4]FIG. 4 is a schematic diagram schematically showing the driving of the second driving part of the movable device. [Figure 5] FIG. 5 is a diagram showing an example of the waveform of the driving voltage applied to the piezoelectric driving part group A of the movable device. [Figure 6] FIG. 6 is a diagram showing an example of the time change of the swing angle around the second axis of the reflecting surface when the movable speed around the second axis of the reflecting surface is constant (uniform). [Figure 7] FIG. 7 is a diagram showing an example of a projected image when the movable speed around the second axis of the reflecting surface is constant (uniform). [Figure 8] FIG. 8 is a diagram showing an example of the time change of the swing angle around the second axis of the reflecting surface when the movable speed around the second axis of the reflecting surface is not constant (uniform). [Figure 9] FIG. 9 is a diagram showing an example of a projected image when the movable speed is not uniform. [Figure 10] FIG. 10 is a diagram showing an example of the behavior of the swing angle of the reflecting surface when both driving voltages A and B are driven with a simple sawtooth wave. [Figure 11] FIG. 11 is a diagram showing an example of the behavior of the swing angle of the reflecting surface when driven by driving voltages A and B alone. [Figure 12] FIG. 12 is a diagram showing an example of the behavior of the swing angle of the reflecting surface when driven alone by changing the symmetry of driving voltage B. [Figure 13] FIG. 13 is a diagram showing an example of the phase relationship between driving voltage A and driving voltage B for controlling the movable speed of the reflecting surface to be constant. [Figure 14] FIG. 14 is a plan view showing an example of the configuration of the detection part of the movable device. [Figure 15] FIG. 15 is a diagram showing an example of the relationship between the phase difference, symmetry, and linearity value. [Figure 16] FIG. 16 is a diagram showing an example of the relationship with the linearity value between line segment AB with respect to FIG. 15. [Figure 17] FIG. 第十七 is a block diagram showing an example of the schematic configuration of the control system of the movable device. [Figure 18] It should be noted that there is an error in the tag in the original text, which should be FIG. 17 is a block diagram showing an example of the schematic configuration of the control system of the movable device. instead of 図17は、可動装置の制御システムの概略構成の一例を示すブロック図である。 with Chinese characters. The above translation has been corrected accordingly.FIG. 18 is a diagram showing an example of a process for searching for an optimal setting of a combination of a phase difference and symmetry. [Figure 19] FIG. 19 is a flowchart showing an example of a process in which a control device changes settings of the symmetry of a drive signal and the phase difference between drive signals. [Figure 20] FIG. 20 is a block diagram showing an example of a schematic configuration of a control system for a movable device according to the second embodiment. [Figure 21] FIG. 21 is a diagram showing an example of a process for searching for an optimal setting of a combination of a phase difference and symmetry. [Figure 22] FIG. 22 is a diagram showing an example of a search process for an optimal setting in the case of a diamond shape. [Figure 23] FIG. 23 is a flowchart showing an example of a process in which a control device changes settings of the symmetry of a drive signal and the phase difference between drive signals. [Figure 24] FIG. 24 is a diagram showing an example of an overall flow from when the movable device is powered on to when it is powered off. [Figure 25] FIG. 25 is a schematic diagram showing a configuration example of an optical deflection device. [Figure 26] FIG. 26 is a hardware configuration diagram of an example of the optical deflection device 10. [Figure 27] FIG. 27 is a functional block diagram of an example of a control device for an optical deflection device. [Figure 28] FIG. 28 is a flowchart of an example of a process of an optical deflection device. [Figure 29] FIG. 29 is a schematic diagram of a vehicle equipped with a head-up display device which is an example of an image projection device. [Figure 30] FIG. 30 is a schematic diagram of an example of a head-up display device. [Figure 31] FIG. 31 is a perspective view illustrating the appearance of an HMD. [Figure 32] FIG. 32 is a diagram partially illustrating the configuration of an HMD.

Embodiments for Carrying Out the Invention

[0011] Embodiments of the movable device, optical deflection device, image projection device, mobile body, and head-mounted display will be described in detail below with reference to the attached drawings.

[0012] (First Embodiment) In the following, the first drive unit and the second drive unit correspond to the "movable parts".

[0013] (Configuration of the movable device) Figures 1 and 2 show an example of the configuration of a movable device according to the first embodiment. Figure 1 is a plan view of a movable device in which the first drive unit is of the cantilever type. Figure 2 is a cross-sectional view of the movable device of Figure 1 along the second axis. Figure 3 is a plan view of a movable device in which the first drive unit is of the double-support type. First, the configuration of the movable device will be described with reference to Figures 1 and 2.

[0014] The movable device 13 includes a reflector 101, first drive units 110a and 110b, a first support unit 120, second drive units 130a and 130b, a second support unit 140, and an electrode connection unit 150, and is driven by a control device via the electrode connection unit 150. As an example, the movable device 13 is a MEMS (Micro Electromechanical System).

[0015] The reflecting section 101 reflects incident light. The first drive units 110a and 110b are connected to the reflecting section 101 and drive the reflecting section 101 around a first axis parallel to the Y-axis. The first support unit 120 supports the reflecting section 101 and the first drive units.

[0016] The second drive units 130a and 130b are connected to the first support unit 120 and drive the reflector unit 101 and the first support unit 120 around a second axis parallel to the X-axis. In the example in Figure 1, the second drive unit 130a and the second drive unit 130b each have a meander structure composed of a plurality of second piezoelectric drive units 131a to 131f and 132a to 132f that are connected in a folded manner.

[0017] The second support portion 140 supports the second drive portion. The electrode connection portion 150 is electrically connected to the first drive portion and the second drive portion.

[0018] The movable device 13 is formed by, for example, shaping a single SOI (Silicon On Insulator) substrate by etching or the like, and then forming a reflective surface 14, first piezoelectric drive units 112a, 112b, second piezoelectric drive units 131a to 131f, second piezoelectric drive units 132a to 132f, electrode connection units 150, etc., on the formed substrate, thereby integrally forming each component. Note that the formation of each of the above components may be performed after the SOI substrate is formed, or during the SOI substrate is formed.

[0019] The SOI substrate is a substrate in which a silicon oxide layer 162 is provided on a first silicon layer made of single-crystal silicon (Si), and a second silicon layer made of single-crystal silicon is provided on the silicon oxide layer. Hereafter, the first silicon layer will be referred to as the silicon support layer 161, and the second silicon layer as the silicon active layer 163.

[0020] Because the silicon active layer 163 has a smaller thickness in the Z-axis direction compared to the X-axis or Y-axis direction, the component composed of the silicon active layer 163 functions as an elastic part with elasticity.

[0021] Furthermore, the SOI substrate does not necessarily have to be planar; it may have curvature or other properties. Also, the material used to form the movable device 13 is not limited to an SOI substrate, as long as it can be integrally molded by etching or the like and can be partially elasticized.

[0022] The reflective portion 101 is composed of, for example, a circular reflective portion base 102 and a reflective surface 14 formed on the +Z side surface of the reflective portion base 102. The reflective portion base 102 is composed of, for example, a silicon active layer 163. The reflective surface 14 is composed of, for example, a thin metal film containing aluminum, gold, silver, etc. In addition, the reflective portion 101 may have ribs for reinforcing the reflective portion formed on the -Z side surface of the reflective portion base 102. The ribs are composed of, for example, a silicon support layer 161 and a silicon oxide layer 162, and can suppress distortion of the reflective surface 14 caused by movement.

[0023] The first drive units 110a and 110b consist of two torsion bars 111a and 111b, one end of which is connected to the reflector base 102 and which extend in the first axial direction to movably support the reflector 101, and first piezoelectric drive units 112a and 112b, one end of which is connected to the torsion bar and the other end of which is connected to the inner circumference of the first support unit 120.

[0024] The torsion bars 111a and 111b are made of a silicon active layer 163. The first piezoelectric drive units 112a and 112b are made by forming a lower electrode 171, a piezoelectric part 172, and an upper electrode 173 in that order on the +Z side surface of the silicon active layer 163, which is the elastic part. The upper electrode 173 and the lower electrode 171 are made of, for example, gold (Au) or platinum (Pt). The piezoelectric part 172 is made of, for example, PZT (lead zirconate titanate), which is a piezoelectric material.

[0025] The first support portion 120 is a rectangular support formed to surround the reflective portion 101, and is composed of, for example, a silicon support layer 161, a silicon oxide layer 162, and a silicon active layer 163.

[0026] The second drive units 130a and 130b are each composed of second piezoelectric drive units 131a-131f and 132a-132f, respectively. One end of each second drive unit 130a and 130b is connected to the outer circumference of the first support unit 120, and the other end is connected to the inner circumference of the second support unit 140. At this time, the connection points between the second drive unit 130a and the first support unit 120, the connection points between the second drive unit 130b and the first support unit 120, the connection points between the second drive unit 130a and the second support unit 140, and the connection points between the second drive unit 130b and the second support unit 140 are point-symmetric with respect to the center of the reflective surface 14.

[0027] The second drive units 130a and 130b are constructed by forming a lower electrode 171, a piezoelectric part 172, and an upper electrode 173 in that order on the +Z side surface of the silicon active layer 163, which is an elastic part. The upper electrode 173 and the lower electrode 171 are made of, for example, gold (Au) or platinum (Pt). The piezoelectric part 172 is made of, for example, PZT (lead zirconate titanate), which is a piezoelectric material.

[0028] The second support portion 140 is a rectangular support formed to surround the reflective portion 101, the first drive portions 110a and 110b, the first support portion 120, and the second drive portions 130a and 130b, for example, a silicon support layer 161, a silicon oxide layer 162, and a silicon active layer 163.

[0029] The electrode connection portion 150 is formed, for example, on the +Z side surface of the second support portion 140, and is electrically connected to the upper electrodes 173 and lower electrodes 171 of the first piezoelectric drive units 112a, 112b, the second piezoelectric drive units 131a-131f, 132a-132f, and the control device 11 via electrode wiring made of aluminum (Al). The upper electrodes 173 or lower electrodes 171 may be directly connected to the electrode connection portion 150, or they may be indirectly connected by connecting the electrodes to each other.

[0030] In this embodiment, the piezoelectric element 172 was described as being formed on the +Z side, which is one surface of the elastic silicon active layer 163. However, it may also be provided on the other surface of the elastic part, such as the -Z side, or on both the one and the other surface of the elastic part.

[0031] Furthermore, the shape of each component is not limited to that of the embodiment, as long as the reflector 101 can be driven around the first axis or the second axis. For example, the torsion bars 111a, 111b and the first piezoelectric drive units 112a, 112b may have a curved shape.

[0032] Furthermore, an insulating layer made of a silicon oxide film may be formed on at least one of the following surfaces: the +Z side surface of the upper electrode 173 of the first drive units 110a and 110b, the +Z side surface of the first support unit 120, the +Z side surface of the upper electrode 173 of the second drive units 130a and 130b, and the +Z side surface of the second support unit. In this case, electrode wiring is provided on the insulating layer, and the insulating layer is partially removed or not formed as an opening only at the connection spots where the upper electrode 173 or lower electrode 171 is connected to the electrode wiring. This increases the design flexibility of the first drive units 110a and 110b, the second drive units 130a and 130b, and the electrode wiring, and also suppresses short circuits caused by contact between electrodes. In addition, the silicon oxide film also functions as an anti-reflective material.

[0033] [Control of movable devices] The piezoelectric elements 172 of the first drive units 110a, 110b and the second drive units 130a, 130b undergo deformation proportional to the potential of the applied voltage when a positive or negative voltage is applied in the polarization direction, such as expansion and contraction, exhibiting a so-called inverse piezoelectric effect. The first drive units 110a, 110b and the second drive units 130a, 130b utilize the above-mentioned inverse piezoelectric effect to move the reflector 101.

[0034] At this time, the angle formed between the XY plane and the reflective surface 14 of the reflecting part 101 when the reflective surface 14 is tilted in the +Z direction or the -Z direction with respect to the XY plane is called the deflection angle. In this case, the +Z direction is defined as the positive deflection angle, and the -Z direction is defined as the negative deflection angle.

[0035] First, the driving of the first drive units 110a and 110b by the control device 11 will be explained. The control device 11 controls the first drive units 110a and 110b by applying a drive voltage. In the first drive units 110a and 110b, when a drive voltage is applied in parallel to the piezoelectric parts 172 of the first piezoelectric drive units 112a and 112b via the upper electrode 173 and the lower electrode 171, each piezoelectric part 172 deforms. Due to the action of this deformation of the piezoelectric parts 172, the first piezoelectric drive units 112a and 112b bend. As a result, a driving force around the first axis acts on the reflector 101 via the twisting of the two torsion bars 111a and 111b, and the reflector 101 moves around the first axis.

[0036] Therefore, the control device 11 can move the reflector 101 around the first axis at a period of the predetermined sinusoidal drive voltage by applying a predetermined sinusoidal drive voltage in parallel to the first piezoelectric drive units 112a and 112b of the first drive units 110a and 110b.

[0037] For example, if the frequency of the sinusoidal voltage is set to approximately 20 kHz, which is about the same as the resonant frequency of the torsion bars 111a and 111b, the reflector 101 can be made to resonate and vibrate at approximately 20 kHz by utilizing the mechanical resonance caused by the twisting of the torsion bars 111a and 111b.

[0038] The movable device 13 in Figure 1 is a cantilever type movable device in which first piezoelectric drive units 112a and 112b extend from torsion bars 111a and 111b toward the +X direction. However, the device is not limited to this configuration as long as the reflector 101 is moved by a piezoelectric unit to which voltage is applied. For example, as shown in Figure 3, a double-supported movable device with first piezoelectric drive units 212a and 212b extending toward the +X direction from torsion bars 211a and 211b and first piezoelectric drive units 212c and 212d extending toward the -X direction may be used. Alternatively, other configurations may be used in which the reflector 101 is moved in only one axis direction.

[0039] (Driving principle) Next, the driving principle of the second drive units 130a and 130b by the control device 11 will be explained using Figures 4 to 13. Here, among the multiple second piezoelectric drive units 131a to 131f of the second drive unit 130a in Figure 1, the even-numbered second piezoelectric drive units, i.e., the second piezoelectric drive units 131b, 131d, and 131f, counting from the second piezoelectric drive unit (131a) closest to the reflector 101, are designated as piezoelectric drive unit group A. Furthermore, among the multiple second piezoelectric drive units 132a to 132f of the second drive unit 130b, the odd-numbered second piezoelectric drive units, i.e., the second piezoelectric drive units 132a, 132c, and 132e, counting from the second piezoelectric drive unit (132a) closest to the reflector 101, are similarly designated as piezoelectric drive unit group A. Furthermore, among the multiple second piezoelectric drive units 131a to 131f of the second drive unit 130a, the odd-numbered second piezoelectric drive units, starting from the second piezoelectric drive unit (131a) closest to the reflector 101, namely second piezoelectric drive units 131a, 131c, and 131e, are designated as piezoelectric drive unit group B. Similarly, among the multiple second piezoelectric drive units 132a to 132f of the second drive unit 130b, the even-numbered second piezoelectric drive units, starting from the second piezoelectric drive unit (132a) closest to the reflector 101, namely 132b, 132d, and 132f, are also designated as piezoelectric drive unit group B.

[0040] The control device 11 applies a drive voltage to drive the second drive units 130a and 130b. As an example, the second drive unit 130b will be explained. In the second drive unit 130b, piezoelectric drive unit group A and piezoelectric drive unit group B correspond to a "pair of movable parts". These piezoelectric drive unit group A and piezoelectric drive unit group B operate to tilt the reflector 101. The same applies to the second drive unit 130a, although the explanation is omitted here.

[0041] Figure 4 is a schematic diagram illustrating the drive of the second drive unit 130b of the movable device 13. The dotted lines represent the reflective surface 14 of the reflector 101, etc. As shown in Figure 4(i), when no drive voltage is applied to the piezoelectric drive unit group A and piezoelectric drive unit group B of the second drive unit 130b, the deflection angle by the second drive unit 130b is zero.

[0042] When drive voltages are applied in parallel to the piezoelectric drive unit group A, as shown in Figure 4(ii), the piezoelectric drive unit group A bends and deforms in the same direction, and the reflector 101 moves around the second axis in the -Z direction.

[0043] When drive voltages are applied in parallel to the piezoelectric drive unit group B, as shown in Figure 4(iv), the piezoelectric drive unit group B bends and deforms in the same direction, and the reflector 101 moves around the second axis in the +Z direction.

[0044] As shown in Figures 4(ii) and 4(iv), the second drive unit 130a or 130b simultaneously bends and deforms multiple piezoelectric parts 172 of piezoelectric drive unit group A or multiple piezoelectric parts 172 of piezoelectric drive unit group B, thereby accumulating the amount of movement due to the bending deformation and increasing the swing angle of the reflecting part 101 (reflecting surface 14) around the second axis. For example, as shown in Figure 1, the second drive units 130a and 130b are connected to the first support unit 120 in a point-symmetric manner with respect to the center point of the first support unit 120. Therefore, when a drive voltage is applied to the piezoelectric drive unit group A, a driving force is generated in the second drive unit 130a that moves the connection between the first support unit 120 and the second drive unit 130a in the +Z direction, and a driving force is generated in the second drive unit 130b that moves the connection between the first support unit 120 and the second drive unit 130b in the -Z direction. The amount of movement is accumulated, and the swing angle of the reflecting unit 101 (reflecting surface 14) around the second axis can be increased.

[0045] Furthermore, as shown in Figure 4(iii), when the amount of movement of the reflector 101 by the piezoelectric drive group A due to voltage application is balanced with the amount of movement of the reflector 101 by the piezoelectric drive group B due to voltage application, the deflection angle becomes zero.

[0046] By applying a drive voltage to the second piezoelectric drive units 131a-131f and 132a-132f in a continuous repeating manner as shown in Figures 4(ii) to 4(iv), the reflector unit 101 can be driven around the second axis.

[0047] (Drive voltages A, B) Next, the drive voltage applied to piezoelectric drive unit group A (hereinafter referred to as drive voltage A) and the drive voltage applied to piezoelectric drive unit group B (hereinafter referred to as drive voltage B) will be explained using Figure 5.

[0048] Figure 5(a) shows an example of the waveform of drive voltage A applied to piezoelectric drive unit group A of the movable device 13. Figure 5(b) shows an example of the waveform of drive voltage B applied to piezoelectric drive unit group B of the movable device 13. Figure 5(c) is a superimposed diagram of the waveforms of drive voltage A and drive voltage B.

[0049] As shown in Figure 5(a), the drive voltage A applied to the piezoelectric drive unit group A is, for example, a drive voltage with a sawtooth waveform, and its frequency is, for example, 60 Hz. Furthermore, the waveform of the drive voltage A is set to a predetermined ratio such that, for example, TrA:TfA = 9:1, where TrA is the time width of the rise period as the voltage value increases from the minimum value to the next maximum value, and TfA is the time width of the fall period as the voltage value decreases from the maximum value to the next minimum value. In this case, the ratio of TrA to one period is called the symmetry of the drive voltage A.

[0050] As shown in Figure 5(b), the drive voltage B applied to the piezoelectric drive unit group B is, for example, a drive voltage with a sawtooth waveform, and its frequency is, for example, 60 Hz. Furthermore, the waveform of the drive voltage B is set to a ratio such that, for example, TfB:TrB = 9:1, where TrB is the time width of the rise period as the voltage value increases from the minimum value to the next maximum value, and TfB is the time width of the fall period as the voltage value decreases from the maximum value to the next minimum value. In this case, the ratio of TfB to one period is called the symmetry of the drive voltage B. Also, as shown in Figure 5(c), for example, the period TA of the waveform of drive voltage A and the period TB of the waveform of drive voltage B are set to be the same.

[0051] The sawtooth waveforms of the above-mentioned drive voltages A and B are generated by superimposing sine waves.

[0052] Furthermore, in this example, sawtooth waveform drive voltages A and B are used, but the waveform is not limited to this. It is also possible to change the waveform according to the device characteristics of the movable device 13, such as using a sawtooth waveform with rounded peaks, or a sawtooth waveform with curved straight regions.

[0053] (Relationship between the time evolution of the deflection angle and the high-frequency components) Next, referring to Figures 6 to 9, we will explain the time change of the movement speed of the reflective surface 14 of the movable device 13 around the second axis, that is, the swing angle of the reflective surface 14 around the second axis.

[0054] Figure 6 shows the time change of the deflection angle around the second axis of the reflective surface 14 when the movement speed around the second axis of the reflective surface 14 is constant (uniform). Figure 7 shows the projected image when the movement speed around the second axis of the reflective surface 14 is constant (uniform), indicating that the movement speed is constant for both the first and second axes of the reflective surface 14 and that the scanning operation is appropriate. In this embodiment, the area inside the movement range of the reflective surface 14 is used as the effective image area.

[0055] Figure 8 shows the time change of the deflection angle around the second axis of the reflective surface 14 when the movement speed of the reflective surface 14 around the second axis is not constant (uniform). When the movement speed is not uniform in this way, as shown in Figure 9, differences in brightness occur in areas of density in the projected image, resulting in uneven brightness. Therefore, if there is a fluctuation in the movement speed of the reflective part 101 around the second axis, linear light scanning is hindered, and for example, uneven brightness and distortion occur in the image formed on the scanned surface, leading to a deterioration of image quality.

[0056] The time change of the deflection angle of the reflective surface 14 around the second axis, that is, the movable speed of the reflective surface 14 around the second axis, is preferably linear, as shown in Figure 6. In other words, it is desirable that there is no fluctuation in the movable speed of the reflective part 101 around the second axis. This linearity is called linearity, and the lower the linearity value, the better the linearity and the less brightness unevenness there is. There is a correlation between linearity and brightness unevenness. However, in reality, as shown in Figure 8, fluctuations occur in the movable speed of the deflection angle during the movement of the reflective part 101 around the second axis by the second drive units 130a and 130b.

[0057] This fluctuation is thought to be partly caused by the superposition of high-frequency components on the deflection angle due to elastic vibrations occurring in the elastic parts that support the second support section 140 and the drive sections 130a and 130b.

[0058] In this embodiment, the high-frequency components superimposed by the elastic vibration of the elastic part are suppressed, and the drive voltage is controlled so that the moving speed becomes uniform. Referring to Figures 10 to 13, the reason why the uniformity of the moving speed of the reflecting part 101 is improved by controlling the drive voltage will be explained in detail.

[0059] Figure 10 shows the behavior of the deflection angle of the reflecting surface when both drive voltages A and B are driven by simple sawtooth waves. As shown in Figure 10, the drive voltage is affected by superimposed high-frequency components, causing the movement speed to fluctuate and the movement speed of the reflecting surface to become non-uniform.

[0060] Figure 11 shows the behavior of the deflection angle of the reflecting surface when driven by drive voltages A and B individually. Note that when both drive voltages A and B are driven, the deflection angle of the reflecting surface behaves approximately the same as (deflection angle A) - (deflection angle B) when driven individually.

[0061] Next, we will explain the behavior of the deflection angle of the reflecting surface when the symmetry of the drive voltage B is changed and the surface is driven independently.

[0062] Figure 12 shows the behavior of the deflection angle of the reflecting surface when the symmetry of drive voltage B is changed and the device is driven independently. As shown in Figure 12, the gentler the voltage slope in the falling edge (scanning section) of drive voltage B, the smaller the high-frequency amplitude becomes. Therefore, without changing drive voltage A, the symmetry of drive voltage B is changed so that the high-frequency amplitude generated by drive voltage A matches the high-frequency amplitude generated by drive voltage B.

[0063] Figure 13 shows the phase relationship between drive voltage A and drive voltage B, which controls the moving speed of the reflective surface to a constant level. As shown in Figure 13, the phase difference between drive voltage A and drive voltage B is adjusted so that the high frequencies generated by drive voltage A and drive voltage B are exactly in opposite phase.

[0064] (Example of a movable device for suppressing high-frequency components) Figure 14 is a plan view showing an example of the configuration of the detection unit of the movable device. The movable device 13 shown in Figure 14 has a detection unit 140a which is arranged parallel to the second drive unit 130a with a small gap between them and without contact, and a detection unit 140b which is arranged parallel to the second drive unit 130b with a small gap between them and without contact. Specifically, the detection units 140a and 140b are arranged inside the meander structure as shown in Figure 14, and the number of units is arranged according to the number of meander stages. Each detection unit 141a to 141f and 142a to 142f is narrower in width and approximately the same length as each second piezoelectric drive unit 131a to 131f and second piezoelectric drive units 132a to 132f, and is rectangular in shape.

[0065] The layer configuration of the detection units 140a and 140b is the same as that of the drive units 130a and 130b. This allows the detection units 140a and 140b to detect information about the movable position of the deflection angle of the reflective surface 14 with respect to the second axis.

[0066] By using the movable position information of the deflection angle of the reflective surface 14 from the detection units 140a and 140b, it is possible to replace it with the actual movable movement of the deflection angle of the reflective surface 14, and it is also possible to control the waveform of the drive voltage to correct the uneven movable speed from the detected position information.

[0067] Figures 15 and 16 show the relationship between the phase difference, symmetry (the symmetry of one drive signal when the symmetry of the other drive signal is fixed), and linearity value between a pair of drive signals. Figure 16 shows the relationship between the linearity value between line segments A and B in relation to Figure 15. As shown in Figure 15, when the first axis direction (hereinafter referred to as the X-axis direction for convenience) in the two-dimensional coordinate system is defined as the phase difference and the second axis direction (hereinafter referred to as the Y-axis direction for convenience) is defined as the symmetry, the linearity tends to decrease monotonically toward the combination of phase difference and symmetry that results in the smallest linearity value, as shown in Figure 16.

[0068] (Control system for movable devices) Figure 17 is a block diagram showing an example of a schematic configuration of the control system for the movable device 13. As shown in Figure 17, the movable device 13 is driven under the control of the control device 11. The control device 11 includes a drive signal generation unit A211-1, a drive signal generation unit B211-2, a drive unit A210-1, a drive unit B210-2, a high-frequency component extraction unit 212, a memory unit 213, a setting change count counter unit 214-1, a setting calculation unit 214-2, and a high-frequency component comparison unit 214-3.

[0069] Here, the "signal generation unit" corresponds to the drive signal generation unit A211-1 and the drive signal generation unit B211-2, the "high-frequency component extraction unit" corresponds to the high-frequency component extraction unit 212, the "memory unit" corresponds to the memory unit 213, and the "drive signal selection unit" corresponds to the setting change count counter unit 214-1, the setting calculation unit 214-2, and the high-frequency component comparison unit 214-3.

[0070] The drive signal generation unit A211-1 outputs drive information to the drive unit A210-1, and the drive unit A210-1 outputs a drive signal to the piezoelectric drive unit group A of the movable device 13 based on the drive information.

[0071] Furthermore, the drive signal generation unit B211-2 outputs drive information to the drive unit B210-2, and the drive unit B210-2 outputs a drive signal to the piezoelectric drive unit group B of the movable device 13 based on the drive information.

[0072] The movable device 13 is driven according to the input drive signal. At that time, detection information, which is information on the movement of the reflective surface 14, is output from the movable device 13 and input to the high-frequency component extraction unit 212. The high-frequency component extraction unit 212 extracts the amplitude of the high-frequency component and outputs it to the memory unit 213. At this time, the setting calculation unit 214-2 stores the counter number from the setting change count counter unit 214-1 in the memory unit 213 as data linked to the values ​​of the two variables, "symmetry" and "phase difference," which are the current setting parameters.

[0073] The setting change count counter unit 214-1 counts the number of setting changes, and when it reaches a predetermined number, it outputs a signal to the high-frequency component comparison unit 214-3 indicating that the predetermined number has been reached.

[0074] When a signal indicating that the specified number of cycles has been reached is received, the high-frequency component comparison unit 214-3 reads the amplitude data of the high-frequency components for the specified number of cycles from the memory unit 213 and calculates the setting parameters (phase difference, symmetry) that minimize the amplitude of the high-frequency components.

[0075] The setting calculation unit 214-2 changes the setting parameters (phase difference, symmetry) according to a predetermined order. When a signal indicating that a predetermined number of setting changes has been reached is input from the setting change count counter unit 214-1, the setting parameters are updated using the setting parameters (phase difference, symmetry) that minimize the amplitude of the high-frequency component calculated by the high-frequency component comparison unit 214-3. At this time, the data in the memory unit 213 and the count of the setting change count counter unit 214-1 are reset. The settings are then changed again according to the predetermined order and the updated setting parameters (phase difference, symmetry).

[0076] The setting parameters (phase difference and symmetry) calculated by the setting calculation unit 214-2 are input to the drive signal generation unit B211-2. Based on the input symmetry and phase difference, the drive signal generation unit B211-2 updates the drive information and outputs it to the drive unit B210-2 to control the drive waveform.

[0077] In this example, the drive information was updated for drive unit B, but it is also possible to update the drive information for drive unit A, or to update the drive information for both drive units A and B.

[0078] Figure 18 shows an example of a process for searching for the optimal setting of the combination of phase difference and symmetry (the symmetry of one drive signal when the symmetry of the other drive signal is fixed) between a pair of drive signals. First, as shown in Figure 18, the positions of the phase difference and symmetry combinations of p2 to p9 are determined so that they are equally spaced left and right, and also equally spaced up and down, with the position of p1 as the reference (center) and surrounding the coordinate of p1 (hereinafter referred to as position).

[0079] Next, the phase difference and symmetry settings are changed sequentially from p1 to p9, and the linearity value at each point is measured. The point where the linearity is smallest among the measured p1 to p9 is p(minimum), which in this example is p(4). With the position of p(minimum) as the center, new combinations of p2' to p9' are determined so that the intervals are half the original equal spacing on the left and half the original spacing on the top and bottom.

[0080] Next, similarly, the phase difference and symmetry settings are sequentially changed from p1' to p9', and the linearity value at each point is measured. Using p(minimum)', the point with the smallest linearity among the measured p'1 to p'9 points, new combinations of phase difference and symmetry are determined so that the intervals are half the size of the points to the left and half the size of the points to the top and bottom. By repeating this process, the optimal settings can be derived. In this example, nine points from p1 to p9 are used, but any number of points can be used, not just nine.

[0081] Figure 19 is a flowchart showing an example of the process by which the control device 11 changes the settings for the symmetry of the drive signals and the phase difference between the drive signals. In the following, MEMS corresponds to a movable device.

[0082] First, the control device 11 performs initial settings (S1). For example, if there are 9 points p1 to p9, the control device 11 sets the number of steps to 9 (p1 to p9), sets the number of searches to 2, sets the high-frequency amplitude threshold to a linearity value that is not recognized as brightness unevenness in the projected image, and sets the phase difference and symmetry which will be the starting settings.

[0083] Next, the control device 11 prepares (updates) the phase difference and symmetry settings for pX (p1~p9) in step (S2).

[0084] Next, the control device 11 resets the step counter and then resets the data stored in the memory unit 213 (S3). In one example, the step counter advances from 1, 2, 3... and returns to 1 when it reaches 9.

[0085] Next, the control device 11 selects the MEMS drive settings (phase difference, symmetry) based on the current step number (p1-9) (S4).

[0086] Next, the control device 11 drives the MEMS according to the settings in S4 (S5).

[0087] Next, the control device 11 acquires a high-frequency amplitude superimposed on the detection signal that traces the mirror deflection angle from the MEMS mirror (S6).

[0088] Next, the control device 11 stores the high-frequency amplitude acquired in S6 and the number of steps in the memory unit 213 (S7).

[0089] Next, the control device 11 determines whether the number of step updates has reached the number of steps (S8).

[0090] Next, since the step update count has not reached the step number, the control device 11 increments the step update count by +1 and proceeds to S4 (S9).

[0091] Next, the control device 11, having reached the step update count, optimizes the MEMS drive settings (phase difference, symmetry) to minimize the high-frequency amplitude stored in memory (S10).

[0092] Next, the control device 11 determines whether the minimum high-frequency amplitude obtained in S10 is smaller than the high-frequency amplitude set in S1 (S11). If it is smaller than the set high-frequency amplitude threshold, the control device 11 determines that it will not be recognized as brightness unevenness, and terminates the process with the optimal setting as the final setting.

[0093] Next, the control device 11 compares the number of searches with the number of searches set in S1 (S12) because the high-frequency amplitude is greater than the threshold. If the set number of searches has been reached, the control device 11 terminates the process with the optimal setting as the final setting.

[0094] Next, the control device 11 increments the search count by +1 because the search count has not yet reached the set number of searches, and then proceeds to S2 (S13).

[0095] As described above, the movable device 13 according to the first embodiment suppresses the high-frequency components of elastic vibrations occurring in the elastic parts that support the second support part 140 and the drive parts 130a and 130b, and controls the drive voltage so that the movable speed becomes uniform. This makes it possible to shorten the adjustment processing time for elastic vibrations that occur when settings are changed.

[0096] (Second Embodiment) Figure 20 is a block diagram showing the schematic configuration of the control system for a movable device according to the second embodiment. The control device 11 shown in Figure 20 includes a drive signal generation unit A211-1, a drive signal generation unit B211-2, a drive unit A210-1, a drive unit B210-2, a high-frequency component extraction unit 212, a memory unit 213, a setting change count counter unit 214-1, a setting calculation unit 214-2, an internal division point calculation unit 251, and an optimal setting calculation unit 252. Similar to the embodiment of the first embodiment, drive information is input from each drive signal generation unit (drive signal generation unit A211-1, drive signal generation unit B211-2) to each drive unit (drive unit A210-1, drive unit B210-2), and a drive signal is output from each drive unit (drive unit A210-1, drive unit B210-2) to the movable device 13 based on the drive information. The movable device 13 is driven according to the input drive signal. The movable device 13 outputs detection information, which is information about the movement of the reflective surface, and inputs it to the high-frequency component extraction unit 212. The high-frequency component extraction unit 212 extracts the amplitude of the high-frequency component and outputs it to the memory unit 213.

[0097] Here, the "drive signal selection unit" corresponds to the setting change count counter unit 214-1, the setting calculation unit 214-2, the internal division point calculation unit 251, and the optimal setting calculation unit 252.

[0098] In the second embodiment, when storing the amplitude of the high-frequency component in the memory unit 213, the setting calculation unit 214-2 also stores the counter count from the setting change count counter unit 214-1 in the memory unit 213 as data linked to the current setting parameters (symmetry, phase difference).

[0099] The setting change count counter unit 214-1 counts the number of setting changes, and when it reaches a predetermined number, it outputs a signal to the internal division point calculation unit 251 indicating that the predetermined number has been reached.

[0100] When a signal indicating that a specified number of cycles has been reached is received, the internal division point calculation unit 251 reads the amplitude data of the high-frequency components for the specified number of cycles from the memory unit 502 and calculates the internal division point from the linearity value at the set parameter position and the linearity value at the adjacent set parameter position.

[0101] The calculated internal division points are input to the optimal setting calculation unit 252, and the intersection points of the internal division points connected by lines are used as the optimal setting parameters. Using these optimal setting parameters, the setting calculation unit 214-2 updates the setting parameters. At this time, the data in the memory unit 213 and the count of the setting change count counter unit 214-1 are reset. The updated setting parameters (phase difference and symmetry) are output to the drive signal generation unit B211-2. Based on the input symmetry and phase difference, the drive signal generation unit B211-2 updates the drive information and outputs it to the drive unit B210-2 to control the drive waveform.

[0102] In this example, the drive information was updated for drive unit B, but it is also possible to update the drive information for drive unit A, or to update the drive information for both drive units A and B.

[0103] Figure 21 shows an example of a process for searching for the optimal setting of the combination of phase difference and symmetry (the symmetry of one drive signal when the symmetry of the other drive signal is fixed) between a pair of drive signals. First, the positions of the phase difference and symmetry combinations for rectangles p1 to p4 are determined as shown in Figure 21. Next, the settings for the phase difference and symmetry are changed sequentially from p1 to p4, and the linearity values ​​(l1 to l4) at each point are measured.

[0104] Next, we determine the internal division points from adjacent positions (p1 and p2, p2 and p3, p3 and p4, p4 and p1) based on the measured linearity values ​​of p1 to p4.

[0105] If the linearity value at p(n) is l(n), then the internal division point between p1 and p2 is n12 = p1 + l1 / (l1 + l2). Each internal division point, found in this way, can be expressed as follows.

[0106] n23 = p2 + l2 / (l2 + l3)

[0107] n34 = p4 + l4 / (l4 + l3)

[0108] n41 = p1 + l1 / (l1 + l4)

[0109] Here, we connect the opposite internal division points with lines, and determine the optimal position at the point where these lines intersect. This allows us to estimate the optimal position by measuring linearity at four points. Therefore, this method shortens the search time compared to the method of sequentially comparing linearity to find the optimal position. Furthermore, by updating the four points again with the optimal position as the center and repeating the process, we can derive an optimal setting with higher accuracy.

[0110] Note that four points is just one example; any number of points is acceptable, not just four.

[0111] Furthermore, while a rectangular shape was used as an example here, the design is not limited to this. For example, a shape like that shown in Figure 22 would also be acceptable.

[0112] Figure 22 shows an example of the search process for the optimal setting in the case of a rhombus shape. The same process can be performed even when the phase difference and symmetry are changed simultaneously, as in this rhombus shape.

[0113] Figure 23 is a flowchart showing an example of the process by which the control device 11 changes the settings for the symmetry of the drive signal and the phase difference between the drive signals. First, the control device 11 performs initial settings (S21). As an example, the control device 11 sets the number of steps to 4 (p1 to p4), sets the number of searches to 1, sets the high-frequency amplitude threshold to a linearity value that is not recognized as brightness unevenness in the projected image, and then sets the phase difference and symmetry as the starting settings.

[0114] Next, the control device 11 prepares (updates) the phase difference and symmetry settings for pX (p1~p4) in step (S22).

[0115] Next, the control device 11 resets the step counter (S23). In one example, the step counter advances from 1 to 4, and when it reaches 4, it resets to 1.

[0116] Next, the control device 11 selects the MEMS drive settings (phase difference, symmetry) based on the current step number (p1-4) (S24).

[0117] Next, the control device 11 drives the MEMS according to the settings in S24 (S25).

[0118] Next, the control device 11 acquires a high-frequency amplitude superimposed on the detection signal that traces the mirror deflection angle from the MEMS mirror (S26).

[0119] Next, the control device 11 stores the high-frequency amplitude acquired in S26 in memory, linked to the number of steps (S27).

[0120] Next, the control device 11 determines whether the number of step updates has reached the number of steps (S28).

[0121] Next, since the step update count has not reached the step number, the control device 11 increments the step update count by +1 and proceeds to S24 (S29).

[0122] Next, when the number of step updates reaches the specified number of steps, the control device 11 calculates an internal division point from the ratio of high-frequency amplitude values ​​in adjacent steps, connects the calculated internal division point with the opposite internal division point using a line (internal division line), and sets the intersection of the internal division lines as the optimal setting for the MEMS drive settings (phase difference, symmetry) (S30).

[0123] Next, the control device 11 drives the MEMS using the MEMS drive settings obtained in S30 (S31).

[0124] Next, the control device 11 acquires a high-frequency amplitude superimposed on the detection signal that traces the mirror deflection angle from the MEMS mirror (S32).

[0125] Next, the control device 11 determines whether the high-frequency amplitude in the optimal setting obtained in S32 is smaller than the high-frequency amplitude set in S1 (S33). If this determination shows that it is smaller than the set high-frequency amplitude threshold, it will not be recognized as brightness unevenness, and the optimal setting will be set as the final setting, and the process will end.

[0126] Next, the control device 11 compares the number of searches with the number of searches set in S1 because the high-frequency amplitude is greater than the threshold (S34). If the set number of searches has been reached, the optimal setting is set as the final setting and the process is terminated.

[0127] Next, since the number of searches has not reached the set number of searches, the control device 11 increments the number of searches by +1 and proceeds to S22 (S35).

[0128] Figure 24 shows an example of the overall flow from power-on to power-off of the movable device. First, the control device 11 performs initial settings after power-on (S41). In the initial settings, the control device 11 sets the MEMS drive frequency and a predetermined laser light intensity.

[0129] Next, the control device 11 performs linearity adjustment (S42).

[0130] Next, the control device 11 starts lighting the laser using a MEMS drive setting that does not recognize brightness unevenness (S43).

[0131] Next, the control device 11 first turns off the laser in order to terminate the projection process (S44).

[0132] Next, the control device 11 stops the MEMS drive, stops the MEMS mirror, and turns off the power (S45).

[0133] (Third embodiment) [Light deflection device] The optical deflection device according to the third embodiment will be described in detail with reference to Figures 25 to 28. In the optical deflection device according to the third embodiment, the control system of the movable device 13 according to the first or second embodiment is applied.

[0134] Figure 25 is a schematic diagram showing the configuration of an example of an optical deflection device. As shown in Figure 25, the optical deflection device 10 includes a control device 11, a light source device 12, and a movable device 13 having a reflective surface 14. The optical deflection device 10 optically scans the surface to be scanned 15 by deflecting the light emitted from the light source device 12 with the reflective surface 14 according to the control of the control device 11.

[0135] The control device 11 is an electronic circuit unit equipped with, for example, a CPU (Central Processing Unit) and an FPGA (Field-Programmable Gate Array). The movable device 13 is, for example, a MEMS device having a reflective surface 14 and having a movable reflective surface 14. The light source device 12 is, for example, a laser device that emits a laser. The scanned surface 15 is, for example, a screen.

[0136] 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.

[0137] The light source device 12 irradiates based on the input drive signal. The movable device 13 moves the reflective surface 14 in at least one of one axis direction or two axis directions based on the input drive signal.

[0138] As a result, for example, by controlling the control device 11 based on image information, which is an example of optical scanning information, the reflective surface 14 of the movable device 13 is moved back and forth in two axial directions within a predetermined range, and the light emitted from the light source device 12 incident on the reflective surface 14 is deflected around a certain axis and optically scanned, thereby projecting an arbitrary image onto the scanned surface 15.

[0139] Next, the hardware configuration of an example of an optical deflection device 10 will be explained using Figure 26. Figure 26 is a hardware configuration diagram of an example of an optical deflection device 10. As shown in Figure 26, the optical deflection device 10 comprises a control device 11, a light source device 12, and a movable device 13, each of which is electrically connected. Of these, the control device 11 includes a CPU 301, RAM 302 (Random Access Memory), ROM 303 (Read Only Memory), FPGA 304, external I / F 305, light source device driver 306, and movable device driver 307.

[0140] The CPU 301 is a central processing unit that reads programs and data from storage devices such as the ROM 303 onto the RAM 302, executes processing, and realizes the overall control and functions of the control device 11.

[0141] RAM302 is a volatile memory device that temporarily holds programs and data.

[0142] ROM303 is a non-volatile memory device that can retain programs and data even when the power is turned off, and stores processing programs and data that the CPU301 executes to control each function of the optical deflection device 10.

[0143] FPGA304 is a circuit that outputs control signals suitable for the light source driver 306 and the movable device driver 307 according to the processing of CPU301.

[0144] The external I / F305 is an interface to external devices, networks, etc. External devices include, for example, higher-level devices such as PCs (Personal Computers), and storage devices such as USB memory, SD cards, CDs, DVDs, HDDs, and SSDs. Networks include, for example, a vehicle's CAN (Controller Area Network), LAN (Local Area Network), and the internet. The external I / F305 only needs to be configured to enable connection or communication with external devices, and an external I / F305 may be provided for each external device.

[0145] The light source device driver sends a drive signal such as a drive voltage to the light source device 12 according to the input control signal. This is an electrical circuit that outputs a signal.

[0146] The movable device driver 307 is an electrical circuit that outputs a drive signal, such as a drive voltage, to the movable device 13 according to the input control signal.

[0147] In the control device 11, the CPU 301 acquires optical scanning information from an external device or network via the external I / F 305. The CPU 301 can acquire optical scanning information as long as it is configured to do so. This could involve storing the optical scanning information in the ROM 303 or FPGA 304 within the control device 11, or by adding a new storage device such as an SSD within the control device 11 and storing the optical scanning information in that device.

[0148] Here, optical scanning information refers to information indicating how to perform optical scanning on the surface to be scanned 15. For example, when displaying an image by optical scanning, the optical scanning information is image data.

[0149] Next, the functional configuration of the control device 11 of the optical deflection device 10 will be explained using Figure 27. Figure 27 is a functional block diagram of an example of a control device for an optical deflection device. These functions are realized by program execution by the CPU 301, hardware, or both.

[0150] As shown in Figure 27, the control device 11 has a control unit 351 and a drive signal output unit 352 as functional units.

[0151] The control unit 351 is implemented by, for example, a CPU 301, an FPGA 304, 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 352. For example, the control unit 351 acquires image data as optical scanning information from an external device, generates a control signal from the image data through predetermined processing, and outputs it to the drive signal output unit 352. The control unit 351 also has the configuration of the first embodiment or the second embodiment. For example, it has a drive signal generation unit A211-1, a drive signal generation unit B211-2, a high-frequency component extraction unit 212, a memory unit 213, a setting change count counter unit 214-1, a setting calculation unit 214-2, and a high-frequency component comparison unit 214-3 as shown in the first embodiment.

[0152] The drive signal output unit 352 is implemented by a light source device driver 306, a movable device driver 307, etc., and outputs a drive signal to the light source device 12 or the movable device 13 based on the input control signal. The movable device driver 307 corresponds to drive units A210-1 and B210-2.

[0153] 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, it is a drive voltage that controls the irradiation timing and irradiation intensity of the light source. Also, for example, in the movable device 13, it is a drive voltage that controls the timing and range of movement of the reflective surface 14 of the movable device 13.

[0154] Next, the process by which the optical deflection device 10 optically scans the surface to be scanned 15 will be explained using Figure 28. Figure 28 is a flowchart of an example of the process of the optical deflection device.

[0155] First, the control unit 351 acquires optical scanning information from an external device, etc. (S51).

[0156] Next, the control unit 351 generates a control signal from the acquired optical scanning information and outputs the control signal to the drive signal output unit 352 (S52).

[0157] Next, the drive signal output unit 352 outputs a drive signal to the light source device 12 and the movable device 13 based on the input control signal (S53).

[0158] Next, the light source device 12 emits light based on the input drive signal, and the movable device 13 moves the reflective surface 14 based on the input drive signal (S54). By driving the light source device 12 and the movable device 13 in this way, the light is deflected in any direction and scanned.

[0159] In the above-described light deflection device 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.

[0160] Furthermore, in the above-described optical deflection device 10, the functions of the control unit 351 and drive signal output unit 352 for the light source device 12 and the movable device 13 are provided in a single control device 11. However, these functions may exist as separate units. For example, a drive signal output device having the drive signal output unit 352 may be provided separately from the control device 11 having the control unit 351. In addition, an optical deflection system may be configured using the movable device 13 having a reflective surface 14 and the control device 11 to perform optical deflection.

[0161] (Fourth embodiment) [Image projection device] Next, the image projection device will be described in detail with reference to Figures 29 and 30. The image projection device is a device that projects images by optical scanning, and is, for example, a head-up display device. In the image projection device according to the fourth embodiment, the control system of the movable device 13 according to the first or second embodiment is applied.

[0162] Figure 29 is a schematic diagram of a vehicle 400 equipped with a head-up display device 500, which is an example of an image projection device. Figure 30 is a schematic diagram of an example of the head-up display device 500.

[0163] As shown in Figure 29, the head-up display device 500 is installed, for example, near the windshield (windshield 401, etc.) of the vehicle 400. Projected light L emitted from the head-up display device 500 is reflected by the windshield 401 and directed towards the driver 402, who is the observer. As a result, the driver 402 can see the image projected by the head-up display device 500 as a virtual image. Alternatively, a combiner may be installed on the inner wall surface of the windshield, and the driver 402 may see a virtual image by projected light reflected by the combiner.

[0164] As shown in Figure 30, the head-up display device 500 emits laser light from red, green, and blue laser light sources 501R, 501G, and 501B. The emitted laser light passes through an incident optical system consisting of collimator lenses 502, 503, and 504 provided for each laser light source, two dichroic mirrors 505 and 506, and a light intensity adjustment unit 507, and is then deflected by a movable device 13 having a reflective surface 14. The deflected laser light then passes through a projection optical system consisting of a free-form mirror 509, an intermediate screen 510, and a projection mirror 511, and is projected onto a screen. In the head-up display device 500, the laser light sources 501R, 501G, and 501B, collimator lenses 502, 503, and 504, and dichroic mirrors 505 and 506 are unitized as a light source unit 530 by an optical housing.

[0165] The head-up display device 500 projects the intermediate image displayed on the intermediate screen 510 onto the windshield 401 of the vehicle 400, thereby allowing the driver 402 to perceive the intermediate image as a virtual image.

[0166] The laser light of each color emitted from the laser light sources 501R, 501G, and 501B is made into approximately parallel light by collimator lenses 502, 503, and 504, respectively, and then combined by two dichroic mirrors 505 and 506. The combined laser light is then adjusted in intensity by an intensity adjustment unit 507 and then scanned in two dimensions by a movable device 13 having a reflective surface 14. The projected light L scanned in two dimensions by the movable device 13 is reflected by a free-form mirror 509 to correct distortion, and then focused onto an intermediate screen 510 to display an intermediate image. The intermediate screen 510 is composed of a microlens array in which microlenses are arranged in two dimensions, and magnifies the projected light L incident on the intermediate screen 510 in units of microlenses.

[0167] The movable device 13 moves the reflective surface 14 back and forth in two axial directions, and scans the projected light L incident on the reflective surface 14 in two dimensions. The drive control of this movable device 13 is synchronized with the light emission timing of the laser light sources 501R, 501G, and 501B.

[0168] The above describes a head-up display device 500 as an example of an image projection device. However, the image projection device can be any device that projects an image by performing a light scan using a movable device 13 having a reflective surface 14. For example, it can be similarly applied to projectors that are placed on a desk or the like and project an image onto a display screen, or to head-mounted display devices that are mounted on a wearable member attached to the observer's head and project an image onto a reflective-transmitting screen on the wearable member, or onto the eyeballs as a screen.

[0169] Furthermore, the image projection device may be mounted not only on vehicles and mounting components, but also on mobile objects such as aircraft, ships, and mobile robots, or on non-mobile objects such as work robots that operate driven objects such as manipulators without moving from their location.

[0170] (Fifth embodiment) [Head-mounted display] Next, a head-mounted display, another example of an image projection device, will be described using Figures 31 to 32. Here, a head-mounted display is a head-mounted display that can be worn on a human head, and can take the form of, for example, eyeglasses. Hereafter, a head-mounted display will be abbreviated as HMD. In the head-mounted display according to the fifth embodiment, the control system of the movable device 13 according to the first or second embodiment is applied.

[0171] Figure 31 is a perspective view illustrating the external appearance of the HMD60. In Figure 31, the HMD60 consists of a front 60a and temples 60b, each provided in a substantially symmetrical arrangement on the left and right sides. The front 60a can be made of, for example, a light guide plate 61, and the optical system, control device, etc., can be built into the temples 60b.

[0172] Figure 32 is a diagram illustrating a partial configuration of the HMD60. Although Figure 32 illustrates the configuration for the left eye, the HMD60 has a similar configuration for the right eye.

[0173] The HMD60 comprises a control device 11, a light source unit 530, a light intensity adjustment unit 507, a movable device 13 having a reflective surface 14, a light guide plate 61, and a half mirror 62.

[0174] The light source unit 530 is a unit comprising the aforementioned laser light sources 501R, 501G, and 501B, collimator lenses 502, 503, and 504, and dichroic mirrors 505 and 506, all enclosed in an optical housing. In the light source unit 530, the three colors of laser light from the laser light sources 501R, 501G, and 501B are combined by the dichroic mirrors 505 and 506. The combined parallel light is emitted from the light source unit 530.

[0175] Light from the light source unit 530 is adjusted in intensity by the light intensity adjustment unit 507 before being incident on the movable device 13. Based on a signal from the control device 11, the movable device 13 moves the reflective surface 14 in the XY direction and scans the light from the light source unit 530 in two dimensions. The drive control of this movable device 13 is synchronized with the light emission timing of the laser light sources 501R, 501G, and 501B, and a color image is formed by the scanning light.

[0176] The scanning light from the movable device 13 enters the light guide plate 61. The light guide plate 61 guides the scanning light to the half mirror 62 while reflecting it off its inner wall surface. The light guide plate 61 is made of a resin or the like that is transparent to the wavelength of the scanning light.

[0177] The half-mirror 62 reflects light from the light guide plate 61 to the back side of the HMD 60 and emits it towards the eyes of the wearer 63. The half-mirror 62 has, for example, a free-form surface shape. The image formed by the scanning light is projected onto the wearer's retina by reflection from the half-mirror 62. Alternatively, it is projected onto the wearer's retina 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 light scanned in the XY direction.

[0178] Because a half-mirror 62 is used, the wearer 63 observes a superimposed image of light from the outside and an image from the scanning light. Alternatively, a mirror can be provided instead of the half-mirror 62 to eliminate light from the outside and allow observation of only the image from the scanning light.

[0179] Finally, the embodiments described above are presented as examples and are not intended to limit the scope of the present invention. Each of these novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications are possible without departing from the spirit of the invention. Furthermore, each embodiment and its variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents. [Explanation of symbols]

[0180] 11 Control device 13 Movable device 210-1 Drive Unit A 210-2 Drive Unit B 211-1 Drive signal generation unit A 211-2 Drive signal generation unit B 212 High frequency component extraction section 213 Memory section 214-1 Setting Change Counter Section 214-2 Setting Calculation Unit 214-3 High-frequency component comparison section 101 Reflector 110a, 110b First drive unit 120 1st support part 130a, 130b Second drive unit 140 Second support part 140a, 140b, 141a~141f, 142a~142f detection unit 150 Electrode connection section A Piezoelectric drive unit group B. Piezoelectric drive unit group [Prior art documents] [Patent Documents]

[0181] [Patent Document 1] Patent No. 6332736

Claims

1. Reflective part, A pair of movable parts that give the respective inclinations to the reflective part, A control unit that inputs a drive signal to each of the aforementioned movable parts to give the tilt, It has, The control unit, A drive signal generation unit generates a drive signal to be input to the movable part, with the ratio of the rise time of the waveform in the period of the drive voltage waveform and the phase difference between the drive signals input to each of the movable parts as variables. A high-frequency component extraction unit extracts high-frequency components from a signal corresponding to the deflection angle of the reflector detected by the drive signal generated by the drive signal generation unit, A memory unit that stores the values ​​set for each of the variables of the drive signal and the high-frequency components extracted from the high-frequency component extraction unit in association with each other. A drive signal selection unit sets multiple combinations for each variable by changing the value of each variable to another combination based on the combination of values ​​set for each variable, and selects from the multiple combinations the combination of values ​​for the variable that minimizes the high-frequency amplitude of the high-frequency component. A movable device having

2. Reflective part, A pair of movable parts that give the respective inclinations to the reflective part, A control unit that inputs a drive signal to each of the aforementioned movable parts to give the tilt, It has, The control unit, A drive signal generation unit generates a drive signal to be input to the movable part, with the ratio of the rise time of the waveform in the period of the drive voltage waveform and the phase difference between the drive signals input to each of the movable parts as variables. A high-frequency component extraction unit extracts high-frequency components from a signal corresponding to the deflection angle of the reflector detected by the drive signal generated by the drive signal generation unit, A memory unit that stores the values ​​set for each of the variables of the drive signal and the high-frequency components extracted from the high-frequency component extraction unit in association with each other. A drive signal selection unit sets multiple combinations for each variable by changing the value of each variable to a different combination based on the combination of values ​​set for each variable, and selects the intersection point where the lines of division points of adjacent coordinates intersect as the value of the variable combination. A movable device having

3. A movable device according to claim 1 or 2, A light source device that irradiates the reflective portion with light, A light deflection device having the following features.

4. A movable device according to claim 1 or 2, A light source device that irradiates the reflective portion with light, A screen onto which an image is projected by scanning light with the aforementioned movable device, An image projection device having the following features.

5. A movable device according to claim 1 or 2, A light source device that irradiates the reflective portion with light, A mobile body having

6. A movable device according to claim 1 or 2, A light source device that irradiates the reflective portion with light, The image-forming unit, which forms an image on the wearer's retina by scanning light with the aforementioned movable device, A head-mounted display having [a specific feature / feature].

Images